68 results on '"D. Richardt"'
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2. New Device for the Treatment of Ischemic Mitral Regurgitation: Proof-of-Concept in an in Vitro Model
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S. Stock, M. Scharfschwerdt, R. Warnecke, D. Richardt, S. Tsvelodub, and H. Sievers
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Pulmonary and Respiratory Medicine ,Surgery ,Cardiology and Cardiovascular Medicine - Published
- 2018
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- View/download PDF
3. Vermeidung von Koronarobstruktionen durch die Verwendung kleinerer Transkatheterklappen
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D. Richardt, Hans H. Sievers, M. Scharfschwerdt, T. Hanke, E. I. Charitos, S. Stock, and Roza Meyer-Saraei
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Pulmonary and Respiratory Medicine ,Gynecology ,medicine.medical_specialty ,business.industry ,Medicine ,Surgery ,Cardiology and Cardiovascular Medicine ,business - Abstract
Die Aortenklappenimplantation mithilfe der kathetergestutzten „Valve-in-valve“-Technik (TAViVI) ist eine Therapieoption fur Patienten mit degenerierten chirurgischen Bioprothesen („surgical aortic valve bioprostheses“, SAVB) und hohem Operationsrisiko. Die hamodynamischen Ergebnisse sind exzellent, allerdings gibt es Bedenken hinsichtlich Koronarobstruktionen, v. a. bei SAVB mit ausen liegendem Perikard, wie beispielsweise der Trifecta (Fa. St. Jude Medical Inc., St. Paul, USA). In vitro wurden Koronarfluss sowie Hydrodynamik vor und nach TAViVI, mit einer kleineren Transkatheterklappe („transcatheter heart valve“ [THV]; Sapien XT; Fa. Edwards Lifesciences LLC, Irvine, USA) als empfohlen, in SAVB mit ausen liegendem Perikard (Trifecta) bestimmt. Die Konstruktion von Aortenwurzelmodellen orientierte sich an bekannten Risikofaktoren. Zur Validierung der Modelle wurde TAViVI nach aktuellen Empfehlungen durchgefuhrt (26-mm-Sapien XT in 25-mm-Trifecta). Im Anschluss erfolgte die Implantation einer kleineren Sapien XT (23 mm). Hydrodynamik und Koronarfluss (links-/rechtskoronarer Fluss [lCF/rCF]) wurden vor und nach TAViVI sowie bei unterschiedlicher Koronarostienhohe (COH, 8 und 10 mm) in einem Pulsduplikator bestimmt. Die Validierung des Modells zeigte eine Koronarobstruktion (p < 0,001). Bei Verwendung einer kleineren THV trat keine signifikante Koronarobstruktion auf (lCF: COH 8 mm, 0,90–0,87 ml/Schlag; COH 10 mm, 0,89–0,82 ml/Schlag; rCF: COH 8 mm, 0,64–0,60 ml/Schlag; COH 10 mm, 0,62–0,58 ml/Schlag). Der mittlere Druckgradient stieg nach TAViVI signifikant an (4–5 mm Hg, p < 0,001). In diesem In-vitro-Modell konnte eine Koronarobstruktion nach TAViVI, die in eine moderne SAVB erfolgte, durch die Verwendung einer kleineren THV vermieden werden.
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- 2017
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4. Chirurgische Therapie linksventrikulärer Aneurysmata
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D. Richardt and H.-H. Sievers
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Pulmonary and Respiratory Medicine ,Gynecology ,medicine.medical_specialty ,business.industry ,medicine ,Surgery ,Cardiology and Cardiovascular Medicine ,Linksventrikulare funktion ,business - Abstract
Durch die Entwicklung postinfarzieller Aneurysmata kann es zu Kinetikstorungen, Bildung linksventrikularer Thromben, malignen Herzrhythmusstorungen und Herzinsuffizienz kommen. Die chirurgische Resektion des Ventrikelaneurysmas stellt bislang die einzig effektive und kausale Therapie dieses Krankheitsbilds dar. Ziele der Ventrikelrekonstruktion sind, den „Remodeling“-Prozess zu stoppen, die geometrischen Ventrikelverhaltnisse wiederherzustellen und damit die Pumpfunktion zu verbessern. Es existieren mehrere Rekonstruktionsverfahren; die am haufigsten verwendete Technik ist die modifizierte Ventrikelrekonstruktion nach Dor. Vorteile dieser Technik bestehen darin, dass alle Anteile des Aneurysmas erfasst werden und eine neue Ventrikelspitze rekonstruiert werden kann. Andere Techniken sind die nach Cooley und die lineare Resektion mit oder ohne Patch-Plastik. Bei klarer Indikationsstellung belegen mehrere Studien eindrucksvoll, dass Patienten mit postinfarziellen Aneurysmata von der operativen Sanierung profitieren.
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- 2013
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5. Saturday, 17 July 2010
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I. Dimova, R. Hlushchuk, A. Makanya, V. Djonov, M. Theurl, W. Schgoer, K. Albrecht, A. Beer, J. R. Patsch, P. Schratzberger, S. Mahata, R. Kirchmair, M. Didie, P. Christalla, T. Rau, T. Eschenhagen, U. Schumacher, Q. Lin, M. Zenke, W. Zimmmermann, M. Hoch, P. Fischer, B. Stapel, E. Missol-Kolka, S. Erschow, M. Scherr, H. Drexler, D. Hilfiker-Kleiner, I. Diebold, A. Petry, P. Kennel, T. Djordjevic, J. Hess, A. Goerlach, J. Castellano, R. Aledo, J. Sendra, P. Costales, L. Badimon, V. Llorente-Cortes, E. Dworatzek, S. Mahmoodzadeh, V. Regitz-Zagrosek, A. Posa, C. Varga, A. Berko, M. Veszelka, P. Szablics, B. Vari, I. Pavo, F. Laszlo, M. Brandenburger, J. Wenzel, R. Bogdan, D. Richardt, M. Reppel, J. Hescheler, H. Terlau, A. Dendorfer, J. Heijman, Y. Rudy, R. Westra, P. Volders, R. Rasmusson, V. Bondarenko, M. D. Ertas Gokhan, M. D. Ural Ertan, P. H. D. Karaoz Erdal, P. H. D. Aksoy Ayca, M. D. Kilic Teoman, M. D. Kozdag Guliz, M. D. Vural Ahmet, M. D. Ural Dilek, C. Poulet, T. Christ, E. Wettwer, U. Ravens, C. Van Der Pouw Kraan, S. Schirmer, J. Fledderus, P. Moerland, T. Leyen, J. Piek, N. Van Royen, A. Horrevoets, F. Fleissner, V. Jazbutyte, J. Fiedler, P. Galuppo, M. Mayr, G. Ertl, J. Bauersachs, T. Thum, S. Protze, A. Bussek, F. Li, R. Hoo, K. Lam, A. Xu, P. Subramanian, E. Karshovska, R. Megens, S. Akhtar, K. Heyll, Y. Jansen, C. Weber, A. Schober, M. Zafeiriou, C. Noack, A. Renger, R. Dietz, L. Zelarayan, M. Bergmann, I. Meln, A. Malashicheva, S. Anisimov, N. Kalinina, V. Sysoeva, A. Zaritskey, A. Barbuti, A. Scavone, N. Mazzocchi, A. Crespi, D. Capilupo, D. Difrancesco, L. Qian, W. Shim, Y. Gu, S. Mohammed, P. Wong, M. Zafiriou, H. Schaeffer, P. Kovacs, J. Simon, A. Varro, P. Athias, J. Wolf, O. Bouchot, D. Vandroux, A. Mathe, A. De Carvalho, G. Laurent, P. Rainer, M. Huber, F. Edelmann, T. Stojakovic, A. Trantina-Yates, M. Trauner, B. Pieske, D. Von Lewinski, A. De Jong, A. Maass, S. Oberdorf-Maass, I. Van Gelder, Y. Lin, J. Li, F. Wang, Y. He, X. Li, H. Xu, X. Yang, R. Coppini, C. Ferrantini, C. Ferrara, A. Rossi, A. Mugelli, C. Poggesi, E. Cerbai, N. Rozmaritsa, N. Voigt, D. Dobrev, M.-C. Kienitz, G. Zoidl, K. Bender, L. Pott, Z. Kohajda, A. Kristof, L. Virag, N. Jost, A. Trafford, B. Prnjavorac, E. Mujaric, J. Jukic, K. Abduzaimovic, K. Brack, V. Patel, J. Coote, G. Ng, R. Wilders, A. Van Ginneken, A. Verkerk, P. Xaplanteris, C. Vlachopoulos, K. Baou, C. Vassiliadou, I. Dima, N. Ioakeimidis, C. Stefanadis, W. Ruifrok, C. Qian, H. Sillje, H. Van Goor, D. Van Veldhuisen, W. Van Gilst, R. De Boer, K. Schmidt, F. Kaiser, J. Erdmann, C. De Wit, O. Barnett, Y. Kyyak, F. Cesana, L. Boffi, T. Mauri, M. Alloni, M. Betelli, S. Nava, C. Giannattasio, G. Mancia, R. Vilskersts, J. Kuka, B. Svalbe, E. Liepinsh, M. Dambrova, A. Zakrzewicz, J. Maroski, B. Vorderwuelbecke, K. Fiedorowicz, L. Da Silva-Azevedo, A. Pries, B. Gryglewska, M. Necki, M. Zelawski, T. Grodzicki, E. Scoditti, M. Massaro, M. Carluccio, A. Distante, C. Storelli, R. De Caterina, O. Kocgirli, S. Valcaccia, V. Dao, T. Suvorava, S. Kumpf, M. Floeren, M. Oppermann, G. Kojda, C. Leo, J. Ziogas, J. Favaloro, O. Woodman, W. Goettsch, A. Marton, C. Goettsch, H. Morawietz, E. Khalifa, Z. Ashour, V. Rupprecht, F. Scalera, J. Martens-Lobenhoffer, S. Bode-Boeger, W. Li, Y. Kwan, G. Leung, F. Patella, A. Mercatanti, L. Pitto, G. Rainaldi, I. Tsimafeyeu, Y. Tishova, N. Wynn, S. Kalinchenko, M. Clemente Lorenzo, M. Grande, F. Barriocanal, M. Aparicio, A. Martin, J. Hernandez, J. Lopez Novoa, C. Martin Luengo, A. Kurlianskaya, T. Denisevich, N. Barth, A. Loot, I. Fleming, Y. Wang, A. Gabrielsen, R. Ripa, E. Jorgensen, J. Kastrup, G. Arderiu, E. Pena, K. Kobus, J. Czyszek, A. Kozlowska-Wiechowska, P. Milkiewicz, M. Milkiewicz, R. Madonna, E. Montebello, Y. Geng, J. Chin-Dusting, D. Michell, M. Skilton, J. Dixon, A. Dart, X. Moore, M. Ehrbar, P. Reichmuth, N. Heinimann, B. Hewing, V. Stangl, K. Stangl, M. Laule, G. Baumann, A. Ludwig, R. Widmer-Teske, A. Mueller, P. Stieger, H. Tillmanns, R. Braun-Dullaeus, D. Sedding, K. Troidl, L. Eller, I. Benli, H. Apfelbeck, W. Schierling, C. Troidl, W. Schaper, T. Schmitz-Rixen, R. Hinkel, T. Trenkwalder, A. Pfosser, F. Globisch, G. Stachel, C. Lebherz, I. Bock-Marquette, C. Kupatt, C. Seyler, E. Duthil-Straub, E. Zitron, E. Scholz, D. Thomas, J. Gierten, C. Karle, R. Fink, T. Padro, R. Lugano, M. Garcia-Arguinzonis, M. Schuchardt, J. Pruefer, M. Toelle, N. Pruefer, V. Jankowski, J. Jankowski, W. Zidek, M. Van Der Giet, P. Fransen, C. Van Hove, C. Michiels, J. Van Langen, H. Bult, R. Quarck, M. Wynants, E. Alfaro-Moreno, M. Rosario Sepulveda, F. Wuytack, D. Van Raemdonck, B. Meyns, M. Delcroix, F. Christofi, S. Wijetunge, P. Sever, A. Hughes, J. Ohanian, S. Forman, V. Ohanian, C. Gibbons, S. Vernia, A. Das, V. Shah, M. Casado, W. Bielenberg, J. Daniel, J.-M. Daniel, K. Hersemeyer, T. Schmidt-Woell, D. Kaetzel, H. Tillmans, S. Kanse, E. Tuncay, H. Kandilci, E. Zeydanli, N. Sozmen, D. Akman, S. Yildirim, B. Turan, N. Nagy, K. Acsai, A. Farkas, J. Papp, A. Toth, C. Viero, S. Mason, A. Williams, S. Marston, D. Stuckey, E. Dyer, W. Song, M. El Kadri, G. Hart, M. Hussain, A. Faltinova, J. Gaburjakova, L. Urbanikova, M. Hajduk, B. Tomaskova, M. Antalik, A. Zahradnikova, P. Steinwascher, K. Jaquet, A. Muegge, G. Wang, M. Zhang, C. Tesi, H. Ter Keurs, S. Kettlewell, G. Smith, A. Workman, I. Lenaerts, P. Holemans, S. Sokolow, S. Schurmans, A. Herchuelz, K. Sipido, G. Antoons, X. Wehrens, N. Li, J. R. Respress, A. De Almeida, R. Van Oort, H. Lohmann, M. Saes, A. Messer, O. Copeland, M. Leung, F. Matthes, J. Steinbrecher, G. Salinas-Riester, L. Opitz, G. Hasenfuss, S. Lehnart, G. Caracciolo, M. Eleid, S. Carerj, K. Chandrasekaran, B. Khandheria, P. Sengupta, I. Riaz, L. Tyng, Y. Dou, A. Seymour, C. Dyer, S. Griffin, S. Haswell, J. Greenman, S. Yasushige, P. Amorim, T. Nguyen, M. Schwarzer, F. Mohr, T. Doenst, S. Popin Sanja, D. Lalosevic, I. Capo, T. Momcilov Popin, A. Astvatsatryan, M. Senan, G. Shafieian, N. Goncalves, I. Falcao-Pires, T. Henriques-Coelho, D. Moreira-Goncalves, A. Leite-Moreira, L. Bronze Carvalho, J. Azevedo, M. Andrade, I. Arroja, M. Relvas, G. Morais, M. Seabra, A. Aleixo, J. Winter, M. Zabunova, I. Mintale, D. Lurina, I. Narbute, I. Zakke, A. Erglis, Z. Marcinkevics, S. Kusnere, A. Abolins, J. Aivars, U. Rubins, Y. Nassar, D. Monsef, G. Hamed, S. Abdelshafy, L. Chen, Y. Wu, J. Wang, C. Cheng, M. Sternak, T. Khomich, A. Jakubowski, M. Szafarz, W. Szczepanski, L. Mateuszuk, J. Szymura-Oleksiak, S. Chlopicki, J. Sulicka, M. Strach, I. Kierzkowska, A. Surdacki, T. Mikolajczyk, W. Balwierz, T. Guzik, V. Dmitriev, E. Oschepkova, O. Polovitkina, V. Titov, A. Rogoza, R. Shakur, S. Metcalfe, J. Bradley, S. Demyanets, C. Kaun, S. Kastl, S. Pfaffenberger, I. Huk, G. Maurer, K. Huber, J. Wojta, O. Eriksson, M. Aberg, A. Siegbahn, G. Niccoli, G. Sgueglia, M. Conte, S. Giubilato, N. Cosentino, G. Ferrante, F. Crea, D. Ilisei, M. Leon, F. Mitu, E. Kyriakakis, M. Philippova, M. Cavallari, V. Bochkov, B. Biedermann, G. De Libero, P. Erne, T. Resink, C. Bakogiannis, C. Antoniades, D. Tousoulis, M. Demosthenous, C. Psarros, N. Sfyras, K. Channon, S. Del Turco, T. Navarra, G. Basta, V. Carnicelli, S. Frascarelli, R. Zucchi, A. Kostareva, G. Sjoberg, A. Gudkova, E. Semernin, E. Shlyakhto, T. Sejersen, N. Cucu, M. Anton, D. Stambuli, A. Botezatu, C. Arsene, E. Lupeanu, G. Anton, J. Patsch, E. Huber, C. Lande, A. Cecchettini, L. Tedeschi, M. Trivella, L. Citti, B. Chen, Y. Ma, Y. Yang, X. Ma, F. Liu, M. Hasanzad, L. Rejali, M. Fathi, A. Minassian, R. Mohammad Hassani, A. Najafi, M. Sarzaeem, S. Sezavar, A. Akhmedov, R. Klingenberg, K. Yonekawa, C. Lohmann, S. Gay, W. Maier, M. Neithard, T. Luescher, X. Xie, Z. Fu, A. Kevorkov, L. Verduci, F. Cremisi, A. Wonnerth, K. Katsaros, G. Zorn, T. Weiss, R. De Rosa, G. Galasso, F. Piscione, G. Santulli, G. Iaccarino, R. Piccolo, R. Luciano, M. Chiariello, M. Szymanski, R. Schoemaker, H. Hillege, S. Rizzo, C. Basso, G. Thiene, M. Valente, S. Rickelt, W. Franke, G. Bartoloni, S. Bianca, E. Giurato, C. Barone, G. Ettore, I. Bianca, P. Eftekhari, G. Wallukat, A. Bekel, F. Heinrich, M. Fu, M. Briedert, J. Briand, J. Roegel, K. Pilichou, S. Korkmaz, T. Radovits, S. Pali, K. Hirschberg, S. Zoellner, S. Loganathan, M. Karck, G. Szabo, A. Pucci, J. Pantaleo, S. Martino, G. Pelosi, M. Matteucci, C. Kusmic, N. Vesentini, F. Piccolomini, F. Viglione, A. L'abbate, J. Slavikova, M. Chottova Dvorakova, W. Kummer, A. Campanile, L. Spinelli, M. Ciccarelli, S. De Gennaro, E. Assante Di Panzillo, B. Trimarco, R. Akbarzadeh Najar, S. Ghaderian, A. Tabatabaei Panah, H. Vakili, A. Rezaei Farimani, G. Rezaie, A. Beigi Harchegani, N. Hamdani, C. Gavina, J. Van Der Velden, H. Niessen, G. Stienen, W. Paulus, C. Moura, I. Lamego, C. Eloy, J. Areias, T. Bonda, M. Dziemidowicz, T. Hirnle, I. Dmitruk, K. Kaminski, W. Musial, M. Winnicka, A. Villar, D. Merino, M. Ares, F. Pilar, E. Valdizan, M. Hurle, J. Nistal, V. Vera, P. Karuppasamy, S. Chaubey, T. Dew, R. Sherwood, J. Desai, L. John, M. Marber, G. Kunst, E. Cipolletta, A. Attanasio, C. Del Giudice, P. Campiglia, M. Illario, A. Berezin, E. Koretskaya, E. Bishop, I. Fearon, J. Heger, B. Warga, Y. Abdallah, B. Meyering, K. Schlueter, H. Piper, G. Euler, A. Lavorgna, S. Cecchetti, T. Rio, G. Coluzzi, C. Carrozza, E. Conti, F. Andreotti, A. Glavatskiy, O. Uz, E. Kardesoglu, O. Yiginer, S. Bas, O. Ipcioglu, N. Ozmen, M. Aparci, B. Cingozbay, F. Ivanes, M. Hillaert, S. Susen, F. Mouquet, P. Doevendans, B. Jude, G. Montalescot, E. Van Belle, C. Castellani, A. Angelini, O. De Boer, C. Van Der Loos, G. Gerosa, A. Van Der Wal, I. Dumitriu, P. Baruah, J. Kaski, O. Maytham, J. D Smith, M. Rose, A. Cappelletti, A. Pessina, M. Mazzavillani, G. Calori, A. Margonato, S. Cassese, C. D'anna, A. Leo, A. Silenzi, M. Baca', L. Biasucci, D. Baller, U. Gleichmann, J. Holzinger, T. Bitter, D. Horstkotte, A. Antonopoulos, A. Miliou, C. Triantafyllou, W. Masson, D. Siniawski, P. Sorroche, L. Casanas, W. Scordo, J. Krauss, A. Cagide, T. Huang, A. Wiedon, S. Lee, K. Walker, K. O'dea, P. Perez Berbel, V. Arrarte Esteban, M. Garcia Valentin, M. Sola Villalpando, C. Lopez Vaquero, L. Caballero, M. Quintanilla Tello, F. Sogorb Garri, G. Duerr, N. Elhafi, T. Bostani, L. Swieny, E. Kolobara, A. Welz, W. Roell, O. Dewald, N. Kaludercic, E. Takimoto, T. Nagayama, K. Chen, J. Shih, D. Kass, F. Di Lisa, N. Paolocci, L. Vinet, M. Pezet, F. Briec, M. Previlon, P. Rouet-Benzineb, A. Hivonnait, F. Charpentier, J. Mercadier, M. Cobo, M. Llano, C. Montalvo, V. Exposito, L. Meems, B. Westenbrink, L. Biesmans, V. Bito, R. Driessen, C. Huysmans, I. Mourouzis, C. Pantos, G. Galanopoulos, M. Gavra, P. Perimenis, D. Spanou, D. Cokkinos, T. Panasenko, S. Partsch, C. Harjung, A. Bogdanova, D. Mihov, P. Mocharla, S. Yakushev, J. Vogel, M. Gassmann, R. Tavakoli, D. Johansen, E. Sanden, C. Xi, R. Sundset, K. Ytrehus, M. Bliksoen, A. Rutkovskiy, L. Mariero, I. Vaage, K. Stenslokken, O. Pisarenko, V. Shulzhenko, I. Studneva, L. Serebryakova, O. Tskitishvili, Y. Pelogeykina, A. Timoshin, A. Vanin, L. Ziberna, M. Lunder, G. Drevensek, S. Passamonti, L. Gorza, B. Ravara, C. Scapin, M. Vitadello, F. Zigrino, J. Gwathmey, F. Del Monte, G. Vilahur, O. Juan-Babot, B. Onate, L. Casani, S. Lemoine, G. Calmettes, B. Jaspard-Vinassa, C. Duplaa, T. Couffinhal, P. Diolez, P. Dos Santos, A. Fusco, D. Sorriento, P. Cervero, A. Feliciello, E. Barnucz, K. Kozichova, M. Hlavackova, J. Neckar, F. Kolar, O. Novakova, F. Novak, C. Barsanti, N. Abraham, D. Muntean, S. Mirica, O. Duicu, A. Raducan, M. Hancu, O. Fira-Mladinescu, V. Ordodi, J. Voelkl, B. Haubner, G. Neely, C. Moriell, S. Seidl, O. Pachinger, J. Penninger, and B. Metzler
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Physiology ,Physiology (medical) ,Cardiology and Cardiovascular Medicine - Published
- 2010
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6. No Effect of Miglitol on the Oral Bioavailability of Single-Dose Phenytoin in Healthy Males
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C. Rosmarin, D. Richardt, Robert Schall, and I. Havlik
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Phenytoin ,Pharmacotherapy ,business.industry ,Miglitol ,Pharmacology toxicology ,Medicine ,Pharmacology (medical) ,General Medicine ,Pharmacology ,business ,Bioavailability ,medicine.drug - Published
- 1997
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7. Neurohumoral activation in acute aortic dissection typ A
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HH Sievers, D Richardt, and HG Richardt
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Pulmonary and Respiratory Medicine ,Aortic dissection ,medicine.medical_specialty ,business.industry ,Internal medicine ,Cardiology ,Medicine ,Surgery ,Cardiology and Cardiovascular Medicine ,business ,medicine.disease - Published
- 2010
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8. An evaluative study of the short-term effects of once-daily, sustained-release theophylline on sleep in nocturnal asthmatics
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D, Richardt and H S, Driver
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Adult ,Male ,Analysis of Variance ,Cross-Over Studies ,Middle Aged ,Asthma ,Bronchodilator Agents ,Circadian Rhythm ,Placebos ,Double-Blind Method ,Theophylline ,Delayed-Action Preparations ,Humans ,Female ,Sleep ,Lung - Abstract
To examine the effects of once-daily, sustained-release theophylline on sleep patterns in nocturnal asthmatics.Double-blind, randomised, cross-over, placebocontrolled trial over 22 days. Seven-day period to establish therapeutic levels of theophylline (11.8 +/- 3 mg/l); 8-day cross-over period of 4 days' placebo or theophylline; 7-day baseline period. Electrophysiological sleep patterns, overnight bronchoconstriction and arterial O2 saturation monitored on nights 7, 11 and 15.Sleep Laboratory, Medical School, University of the Witwatersrand.Twelve volunteers who met the criteria for asthma, had previously used theophylline, were clinically stable and had a history of nocturnal awakenings caused by asthma were enrolled.Sleep-onset latency (SOL), within-sleep wakefulness (WSW), rapid eye movement sleep (REM), slow-wave sleep (SWS), peak expiratory flow rate (PEFR) and arterial oxygen saturation.SOL increased on theophylline--12 minutes (range 7-9 minutes) compared with placebo--6 minutes (range 3-11 minutes); WSW increased from 33 minutes (range 17-66 minutes) on placebo to 72 minutes (range 35-150 minutes) on theophylline. REM sleep was unaltered. SWS decreased in 10-12 patients, but this difference was not significant. Early morning PEFR was significantly better on theophylline in all study limbs.Our findings show that while once-daily, sustained-release theophylline improves bronchodilation in nocturnal asthmatics, it increases nocturnal wakefulness and decreases sleep efficiency during short-term treatment. This may, however, not be a long-term effect.
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- 1996
9. Curdian sulfate in human malaria
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C. Rosmarin, G. Mabera, P. Mabera, A. van Zyl, H. Mbewe, S. Zuba, Philip E. Thuma, G. Simwann, D. Alexander, P. Mbachendu, V. Gendech, Godfrey Biemba, N. Arangies, Robert Schall, D. Richardt, D. Korhov, Y. Kaneko, and I. Havlik
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chemistry.chemical_compound ,Infectious Diseases ,chemistry ,business.industry ,medicine ,Parasitology ,Sulfate ,medicine.disease ,business ,Malaria ,Microbiology - Published
- 1998
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10. An open-label study of duloxetine hydrochloride, a mixed serotonin and noradrenaline re-uptake inhibitor, in patients with DSM-III-R major depressive disorder
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A.D. du Plessis, D. Richardt, Michael Berk, and M. Birkett
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business.industry ,Dsm iii r ,Duloxetine Hydrochloride ,Pharmacology ,medicine.disease ,behavioral disciplines and activities ,Psychiatry and Mental health ,chemistry.chemical_compound ,chemistry ,Open label study ,Rating scale ,Anesthesia ,Endogenous depression ,medicine ,Duloxetine ,Major depressive disorder ,Pharmacology (medical) ,In patient ,Serotonin ,Psychology ,Serotonin Uptake Inhibitors ,Reuptake inhibitor ,business ,Depression (differential diagnoses) ,Biological Psychiatry - Abstract
Duloxetine hydrochloride, a mixed reuptake inhibitor of serotonin and noradrenaline, was studied in a 6 week open-label uncontrolled multicentre design at a dose of 20 mg daily both in in- and outpatients meeting DSM-III-R criteria for unipolar major depressive disorder. Seventy-nine patients took part in the study. The mean score on the 17-item Hamilton Depression Rating Scale at baseline was 24.9 (SD 4.4), decreasing to 8.5 (SD 7.8) after 6 weeks using a last observation carried forward analysis. Clinical response, defined as a 50% reduction in 17-item Hamilton Depression Rating Scale scores, occurred in 78.2% of patients, whereas remission, defined as a 17-item Hamilton Depression Rating Scale score of < or = 6, occurred in 60.3% of patients. Duloxetine hydrochloride was safe and well tolerated in this patient population.
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- 1997
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11. Nonresonant coherent motion of triplet excitons in molecular pairs
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D. Richardt, U. Schmid, and Peter Reineker
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Physics ,Condensed matter physics ,Exciton ,General Physics and Astronomy ,Observable ,Magnetostatics ,Molecular physics ,law.invention ,Magnetic field ,symbols.namesake ,law ,symbols ,Zeeman energy ,Physical and Theoretical Chemistry ,Hamiltonian (quantum mechanics) ,Electron paramagnetic resonance ,Excitation - Abstract
ESR properties of coherent triplet excitons moving between the differently oriented molecules of a nonresonant AB pair in a crystal of the anthracene type are investigated. The model Hamiltonian contains the different electronic excitation energies of the molecular pair, the electronic transfer integral, the Zeeman energy of the triplet spin in an external magnetic field, and the fine structure interactions at the two differently oriented molecules of the pair. As a function of the strength and orientation of the external magnetic field energy eigenvalues, ESR transition energies and transition probabilities for microwave fields orthogonal and parallel to the static magnetic field are calculated analytically in the high field case. The relations of the theoretical results to experimentally observable quantities are discussed.
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- 1982
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12. ESR of triplet naphthalene pairs, evidence for non-resonance
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Peter Reineker, Helmut Port, Markus Schwoerer, H. Sixl, D. Richardt, and H. Hinkel
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Chemistry ,Phonon ,General Physics and Astronomy ,symbols.namesake ,chemistry.chemical_compound ,symbols ,Molecule ,Physical and Theoretical Chemistry ,Atomic physics ,Hamiltonian (quantum mechanics) ,Single crystal ,Hyperfine structure ,Excitation ,Coherence (physics) ,Naphthalene - Abstract
ESR measurements on triplet naphthalene guest pairs in a host single crystal of perdeuterated naphthalene have been performed between 0.7 K and 4.2 K. Hyperfine splitting is partially resolved even at lowest temperatures, if the field H O is oriented along the principal pair axes. At arbitrary orientations however the width of the observed ESR line (M-line) decreases monotonically with increasing temperature, whereas its absolute value depends on crystal quality. The saturation of the ESR transitions at low temperatures produces a dip in the M-line. In order to explain the inhomogeneously broadened lines at lowest temperatures a model is developed in terms of the eigenstates of the hamiltonian of the pair including non-resonance between pair molecules of different excitation energies. We are able to correlate quantitatively the low temperature ESR line width with the width of the inhomogeneously broadened optical line which yields the distribution of guest energies within the crystal. The ESR line narrowing effect at higher temperatures is attributed to random phonon processes disturbing the coherence in the energy transfer.
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- 1978
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13. Quantitative triplet photophysics by picosecond photometry
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A. Von Jena, D. Richardt, and H.E. Lessing
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Inorganic Chemistry ,Photometry (optics) ,Interferometry ,Chemistry ,Picosecond ,Organic Chemistry ,Singlet state ,Photochemistry ,Molecular physics ,Spectroscopy ,Analytical Chemistry - Abstract
The absolute triplet yields of organic compounds are usually probed photochemically by an indirect method, since flash techniques present difficulties in estimating the concentration of triplets generated. Repetitive picosecond photometry provides a novel approach to resolve this problem, since singlet and triplet populations are probed simultaneously. A further refinement is feasible when the role of laser-induced gratings generated in the picosecond interferometer at zero time delay is understood. For the first time, the transient-transmission plot indicates whether there is appreciable internal conversion apart from the deactivation path via the triplet. An investigation of the heavy-atom effect in Uranine and its derivatives is also presented.
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- 1982
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14. ChemInform Abstract: QUANTITATIVE TRIPLET PHOTOPHYSICS BY PICOSECOND PHOTOMETRY
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H.E. Lessing, D. Richardt, and A. Von Jena
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Photometry (optics) ,Interferometry ,Chemistry ,Picosecond ,General Medicine ,Singlet state ,Molecular physics - Abstract
The absolute triplet yields of organic compounds are usually probed photochemically by an indirect method, since flash techniques present difficulties in estimating the concentration of triplets generated. Repetitive picosecond photometry provides a novel approach to resolve this problem, since singlet and triplet populations are probed simultaneously. A further refinement is feasible when the role of laser-induced gratings generated in the picosecond interferometer at zero time delay is understood. For the first time, the transient-transmission plot indicates whether there is appreciable internal conversion apart from the deactivation path via the triplet. An investigation of the heavy-atom effect in Uranine and its derivatives is also presented.
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- 1983
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15. [Career as a Female Physician in Specialist Training].
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Bühren A, Katsari E, and Richardt D
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- Humans, Female, Germany, Specialization, Mentors, Career Mobility, Physicians, Women, Career Choice
- Abstract
Following medical studies and licensing, the choice of a specialty represents a critical starting point for female physicians' careers in Germany. With female doctors comprising 49,2% of the total physician workforce by the end of 2023, their influence in the medical field is undeniable. This demographic shift necessitates effective career planning, as women increasingly dominate medical specialties, including 62,8% in general practice and 51,9% in internal medicine compared to surgery (26,8%).The training phase is sensitive, coinciding with personal decisions regarding partnerships, family planning, and potential relocations. A structured approach to training is essential to navigate the complexities of specialty selection while managing personal aspirations and responsibilities. Regulatory frameworks from regional medical boards outline requirements and provide opportunities for part-time training to accommodate family needs. Networking and mentorship play pivotal roles in facilitating career advancement and addressing the unique challenges faced by female physicians.Building professional networks is crucial for career development. Mentorship offers invaluable guidance, while social media facilitates broader connections within the medical community. Effective communication is a key competency, fostering trust with patients and enhancing interdisciplinary collaboration.As female physicians continue to rise in numbers and influence within Germany's medical landscape, targeted strategies for career development, including networking and effective communication, are vital. The evolving training landscape underscores the importance of supportive structures that empower women in medicine to navigate their professional journeys successfully., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)
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- 2025
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16. Valve-sparing aortic root replacement for valves with paracommissural fenestrations: which valve will fail?
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Kari FA, Czerny M, Borger M, Misfeld M, Rylski B, Zimmer E, Siepe M, Hagl C, Detter C, Petersen J, Richardt D, Ensminger S, Werner P, Andreas M, Peterss S, Pichlmaier M, and Mueller CS
- Abstract
Objectives: To define morphologic risk constellations during valve-sparing aortic root replacement (VSARR) for aortic valves with paracommissural fenestrations., Patients and Methods: Patients from the multicentre prospective intention-to-treat VSARR- registry German Aortic Root Repair Registry (GEARR) were screened for paracommissural cusp fenestrations. We studied a combined end-point of residual aortic regurgitation (rAR) on post-CPB TEE, mid-term progress of rAR (TTE) and aortic valve replacement for AR., Results: Of a total of 762 registry patients (operated 2016-2024), 145 were identified with ≥1 paracommissural cusp fenestration. Eighteen patients (12%) were not treated as planned but underwent composite valved graft (CVG) implantation. Mean follow-up time was 3 years. Upon post-CPB TEE rAR grade 1 or 2 were present in 44 (33%) and 3 (2%) patients. 50% of patients with fenestrations in more than one cusp showed early progression of rAR. At three years, freedom from the combined end-point was 78% (99% CI 74-79%) for the complete study cohort. Patients with a maximum free margin length difference of < 5mm, reflecting balanced root anatomy with respect to sinus and cusp sizes, had a significantly better outcome than those with ≥5mm: at three years, freedom from the combined end-point was 86% (99% CI 80-91%) vs 41% (99% CI 38-46%, p = 0.011). Outcome was worst for patients with cusp prolapse and a free margin length difference of > 5mm (30% vs 70%, p = 0.018)., Conclusions: Fenestrations in more than one cusp, inhomogeneities of cusp free margin lengths, and additional prolapse are associated with inferior outcome after VSARR for valves with paracommissural fenestrations., (© The Author(s) 2025. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)
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- 2025
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17. German Aortic Root Repair Registry-Insights From the First 400 Consecutive Patients.
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Kari FA, Misfeld M, Borger M, Rylski B, Zimmer E, Siepe M, Hagl C, Detter C, Petersen J, Tsvelodub S, Richardt D, Werner P, Andreas M, Pichlmaier M, and Mueller CS
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- Aortic Diseases epidemiology, Follow-Up Studies, Germany epidemiology, Humans, Incidence, Middle Aged, Prospective Studies, Aorta, Thoracic surgery, Aortic Diseases surgery, Forecasting, Registries, Vascular Surgical Procedures statistics & numerical data
- Abstract
Background: The objective was to provide initial data from our prospective valve-sparing aortic root replacement (V-SARR) registry and reasons for conversion to prosthetic aortic valve replacement., Methods: Six centers established an intention-to-treat-design V-SARR-registry (the German Aortic Root Repair Registry; first patient in October 2016); the main inclusion criterion was being scheduled for V-SARR as plan A. Clinical information, operative details, intraoperative valve/root measurements, and clinical and transthoracic echocardiography follow-up-data are documented., Results: Of a total of 449 patients, we report data for 401 (81% male; mean age 51 ± 14 years). Overall, 350 patients underwent V-SARR as scheduled, group A (David variants I 55%, III 2%, IV 13%, V 24%, V-Stanford 2%, and Yacoub remodeling 2%); and 51 were converted to aortic valve replacement (group B). Median follow-up was 11 months (range, 0 to 2.6 years), cumulative follow-up was 279 patient-years. In group B, there were fewer connective tissue disorders (6% vs 16%), fewer patients had left ventricular ejection fraction greater than 50% (60% vs 90%), more had bicuspid aortic valves (45% vs 28%), and fewer patients had preoperative none/trace aortic regurgitation (2% vs 20%). Fewer patients in group B had rare types of bicuspid aortic valve (fused N/L, R/N, 10% vs 30%) and more had unbalanced roots (56% vs 40%). Immediate postoperative aortic regurgitation was none/trace in 79% and mild in 20%. At 30 days, the mean transvalvular pressure gradient was 7 ± 5 mm Hg. None of the patients died in hospital; two strokes occurred. One patient needed early aortic valve replacement as redo surgery., Conclusions: The main factors causing surgeons to convert a planned V-SARR to aortic valve replacement include asymmetry of aortic valve/root, severity of aortic regurgitation, safety reasons (left ventricular ejection fraction), and bicuspid aortic valves (but not rare types). The German Aortic Root Repair Registry will help us identify the impact on long-term outcomes of preoperative and postoperative valvular anatomy and various V-SARR types., (Copyright © 2022 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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18. Time-resolved 3-dimensional magnetic resonance phase contrast imaging (4D Flow MRI) reveals altered blood flow patterns in the ascending aorta of patients with valve-sparing aortic root replacement.
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Oechtering TH, Sieren MM, Hunold P, Hennemuth A, Huellebrand M, Scharfschwerdt M, Richardt D, Sievers HH, Barkhausen J, and Frydrychowicz A
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- Adult, Aged, Aorta diagnostic imaging, Aorta physiopathology, Aortic Aneurysm diagnostic imaging, Aortic Aneurysm physiopathology, Aortic Valve diagnostic imaging, Aortic Valve physiopathology, Blood Flow Velocity, Blood Vessel Prosthesis Implantation adverse effects, Case-Control Studies, Female, Humans, Male, Middle Aged, Models, Cardiovascular, Patient-Specific Modeling, Pilot Projects, Predictive Value of Tests, Prosthesis Design, Prosthesis Failure, Regional Blood Flow, Time Factors, Treatment Outcome, Aorta surgery, Aortic Aneurysm surgery, Blood Vessel Prosthesis, Blood Vessel Prosthesis Implantation instrumentation, Hemodynamics, Imaging, Three-Dimensional, Magnetic Resonance Angiography, Perfusion Imaging methods
- Abstract
Objective: The aim of this study was to compare aortic flow patterns in patients after David valve-sparing aortic root replacement with physiologically shaped sinus prostheses or conventional tube grafts in healthy volunteers., Methods: Twelve patients with sinus prostheses (55 ± 15 years), 6 patients with tube grafts (58 ± 12 years), 12 age-matched, healthy volunteers (55 ± 6 years), and 6 young, healthy volunteers (25 ± 3 years) were examined with time-resolved 3-dimensional magnetic resonance phase contrast imaging (4D Flow MRI). Primary and secondary helical, as well as vortical flow patterns, were evaluated. Aortic arch anatomy as a flow influencing factor was determined., Results: Compared with volunteers, both sinus prostheses and tube grafts developed more than 4 times as many secondary flow patterns in the ascending aorta (sinus prostheses n = 1.6 ± 0.8; tube grafts n = 1.3 ± 0.6; age-matched, healthy volunteers n = 0.3 ± 0.5; young, healthy volunteers n = 0; P ≤ .012) associated with a kinking of the prosthesis itself or at its distal anastomosis. As opposed to round aortic arches in volunteers (n = 16/18), cubic or gothic-shaped arches predominated in patients (n = 16/18, P < .001). In all but 3 volunteers, 2 counter-rotating helices were confirmed in the ascending aorta and were defined as a primary flow pattern. This primary flow pattern did not develop in patients who underwent valve-sparing aortic root replacement., Conclusions: In patients after valve-sparing aortic root replacement, there was an increased number of secondary flow patterns in the ascending aorta. This seems to be related to surgically altered aortic geometry with kinking. Because flow alterations are known to affect wall shear stress, there seems to be an increased risk for vessel wall remodeling. Compared with previous 4D Flow MRI studies, primary flow patterns in the ascending aorta in healthy subjects were confirmed to be more complex. This underlines the importance of thorough examination of 4D Flow MRI data., (Copyright © 2019 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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19. New Device for the Treatment of Functional Ischemic Mitral Regurgitation: Proof of Concept in an In Vitro Model.
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Stock S, Scharfschwerdt M, Warnecke RJ, Richardt D, Tsvelodub S, and Sievers HH
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- Animals, Hemodynamics, Humans, In Vitro Techniques, Materials Testing, Mitral Valve physiopathology, Mitral Valve Insufficiency etiology, Mitral Valve Insufficiency physiopathology, Proof of Concept Study, Prosthesis Design, Recovery of Function, Sus scrofa, Heart Valve Prosthesis, Heart Valve Prosthesis Implantation instrumentation, Mitral Valve surgery, Mitral Valve Annuloplasty instrumentation, Mitral Valve Insufficiency surgery, Myocardial Ischemia complications
- Abstract
Background: Optimal surgical treatment of functional ischemic mitral regurgitation (FIMR) is still controversy. Due to the underlying pathophysiology, stand-alone ring annuloplasty is assumed with a high recurrence rate of mitral regurgitation, thus additional subvalvular repair techniques might improve the results. This in vitro study introduces a new device for subvalvular mitral valve repair., Methods: We developed a new device for subvalvular mitral valve repair, consisting of two frames for papillary muscle (PM) attachment, which are connected with two holding bars serving for fixation of the device on an annuloplasty ring. In the first experimental run, porcine mitral valves including the chordae tendineae and PMs were fixated on a holding device, consisting of a holding ring simulating mitral annulus dilation and height-adjustable frames for PM attachment simulating leaflet tethering. In vitro regurgitant volume was determined in a pulse duplicator. Afterward, the frames for PM attachment were replaced by our newly developed device and the measurements were repeated., Results: In the model simulating FIMR, the regurgitant volume was 44.3 ± 12.38 mL/stroke. After subvalvular reconstruction with our new device, the regurgitant volume was significantly reduced to 33.1 ± 11.68 mL/stroke ( p = 0.009)., Conclusion: In this specific in vitro model, our new device for subvalvular mitral valve reconstruction led to a significant reduction of the regurgitant volume, thus representing a promising technique to potentially improve the results of mitral reconstruction in ischemic functional mitral valve regurgitation. Additional studies are required to further investigate and improve our device., Competing Interests: None., (Georg Thieme Verlag KG Stuttgart · New York.)
- Published
- 2019
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20. Survival and reoperation after valve-sparing root replacement and root repair in acute type A dissection.
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Sievers HH, Richardt D, Diwoky M, Auer C, Bucsky B, Nasseri B, and Klotz S
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- Acute Disease, Adult, Aged, Aged, 80 and over, Aortic Dissection diagnostic imaging, Aortic Dissection mortality, Aortic Dissection physiopathology, Aorta diagnostic imaging, Aorta physiopathology, Aortic Aneurysm diagnostic imaging, Aortic Aneurysm mortality, Aortic Aneurysm physiopathology, Aortic Valve diagnostic imaging, Aortic Valve physiopathology, Female, Hospital Mortality, Humans, Male, Middle Aged, Postoperative Complications mortality, Reoperation, Replantation, Retrospective Studies, Risk Assessment, Risk Factors, Time Factors, Treatment Outcome, Young Adult, Aortic Dissection surgery, Aorta surgery, Aortic Aneurysm surgery, Aortic Valve surgery, Blood Vessel Prosthesis Implantation adverse effects, Blood Vessel Prosthesis Implantation mortality, Cardiac Surgical Procedures adverse effects, Cardiac Surgical Procedures mortality, Postoperative Complications surgery
- Abstract
Objective: Optimal treatment of the dissected root in type A dissection is still controversial. Valve-sparing techniques offer the advantage of better valve performance compared with mechanical valves or bioprostheses. The role of the different valve-preserving methods-root repair and replacement-needs further evaluation., Methods: Follow-up data (median follow-up, 11.4 years; 95% confidence interval [CI], 10.1-12.7; range, 0-22.1 years) of 179 patients with acute type A dissection and root involvement, who underwent a valve-sparing root replacement using reimplantation (n = 44) or remodeling (n = 39) or a valve-sparing root repair (n = 96) between 1993 and 2017 were analyzed with respect to survival and reoperation., Results: Median age of patients with reimplantation was 56.9 (range, 20.2-78), with remodeling 62.6 (range, 31-79.1), and with valve-sparing root repair 64.5 (range, 31-89.6) years. Thirty-day mortality for these groups was 15.9%, 15.4%, and 12.5% (P = .829), late mortality at 15 years was 43.2% (95% CI, 28.1-66.5), 36.7% (95% CI, 19.7-68.1), and 36.5% (95% CI, 23.0-57.9; P = .504). Risk factors for overall mortality were age, connective tissue disease, total arch replacement, surgical time, cross-clamp time, circulatory arrest, and the reimplantation technique. Cumulative incidence of reoperation at 15 years was 13.4% (95% CI, 2.1-24.7), 20% (95% CI, 6.3-33.6), and 13.3% (95% CI, 4.8-21.7; P = .565), respectively., Conclusions: With the different conditions in each group in this study on patients with acute type A dissection the valve-preserving root repair technique has similar long-term rates of survival and reoperation compared with root replacement techniques, underlining its usefulness as a less complex and even faster surgical technique if individually indicated., (Copyright © 2018 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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21. Significance of an additional unenhanced scan in computed tomography angiography of patients with suspected acute aortic syndrome.
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Panagiotopoulos N, Drüschler F, Simon M, Vogt FM, Wolfrum S, Desch S, Richardt D, Barkhausen J, and Hunold P
- Abstract
Aim: To assess potential benefits of an additional unenhanced acquisition in computed tomography angiography (CTA) in patients with suspected acute aortic syndrome (AAS)., Methods: A total of 103 aortic CTA (non-electrocardiography-gated, 128 slices) performed due to suspected AAS were retrospectively evaluated for acute aortic dissection (AAD), intramural hematoma (IMH), or penetrating aortic ulcer (PAU). Spiral CTA protocol consisted of an unenhanced acquisition and an arterial phase. If AAS was detected, a venous phase (delay, 90 s) was added. Images were evaluated for the presence and extent of AAD, IMH, PAU, and related complications. The diagnostic benefit of the unenhanced acquisition was evaluated concerning detection of IMH., Results: Fifty-six (30% women; mean age, 67 years; median, 68 years) of the screened individuals had AAD or IMH. A triphasic CT scan was conducted in 76.8% ( n = 43). 56% of the detected AAD were classified as Stanford type A, 44% as Stanford type B. 53.8% of the detected IMH were classified as Stanford type A, 46.2% as Stanford type B. There was no significant difference in the involvement of the ascending aorta between AAD and IMH ( P = 1.0) or in the average age between AAD and IMH ( P = 0.548), between Stanford type A and Stanford type B in general ( P = 0.650) and between Stanford type A and Stanford type B within the entities of AAD and IMH (AAD: P = 0.785; IMH: P = 0.146). Only the unenhanced acquisitions showed a significant density difference between the adjacent lumen and the IMH ( P = 0.035). Subadventitial hematoma involving the pulmonary trunk was present in 5 patients (16%) with Stanford A AAD. The difference between the median radiation exposure of a triphasic (2737 mGy*cm) compared to a biphasic CT scan (2135 mGy*cm) was not significant ( P = 0.135)., Conclusion: IMH is a common and difficult to detect entity of AAS. An additional unenhanced acquisition within an aortic CTA protocol facilitates the detection of IMH., Competing Interests: Conflict-of-interest statement: None of the authors states a conflict of interest concerning firms and products reported in this study.
- Published
- 2018
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22. Valve performance classification in 630 subcoronary Ross patients over 22 years.
- Author
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Sievers HH, Stierle U, Petersen M, Klotz S, Richardt D, Diwoky M, and Charitos EI
- Subjects
- Adult, Aortic Valve diagnostic imaging, Aortic Valve physiopathology, Blood Vessel Prosthesis Implantation adverse effects, Blood Vessel Prosthesis Implantation mortality, Female, Hemodynamics, Hospital Mortality, Humans, Male, Middle Aged, Postoperative Complications mortality, Postoperative Complications surgery, Progression-Free Survival, Prospective Studies, Prosthesis Design, Recovery of Function, Reoperation, Risk Factors, Time Factors, Young Adult, Aortic Valve surgery, Bioprosthesis, Blood Vessel Prosthesis, Blood Vessel Prosthesis Implantation instrumentation
- Abstract
Objective: To define the function of the "Ross valves" and its clinical meaning in a practical valve performance classification as part of the outcome analysis., Methods: From 1994 to 2017, 630 consecutive patients underwent the subcoronary Ross procedure at our institution. The valve performance classification combines hemodynamics, symptoms, and management criteria. Median follow-up was 12.5 years (maximum 22.3 years, 7404 patient-years, 99.4% completeness)., Results: The mean age of the patients was 44.7 ± 11.9 years. Hospital deaths was 0.3% (n = 2). Twenty years after the operation survival was 73.1% (95% confidence interval [CI], 65.4%-81.6%) and statistically not different from the age- and gender-matched general population; freedom from reoperation was 85.9% (95% CI, 80.2%-92.0%; 0.6% per patient-year), 89.8% (95% CI, 84.3%-95.7%) for autograft, and 91.0% (95% CI, 86.3%-96.0%) for homograft. Preoperative annulus diameter, aortic regurgitation, annulus reinforcement, sinotubular junction reinforcement, and bicuspid aortic valve type were no significant risk factors for reoperation. At 20 years the probability of a patient being in valve performance class I to IV was 5%, 74%, 19%, and 1%, respectively. Time to reoperation was not different in bicuspid and tricuspid aortic valves; preoperative aortic stenosis tended to have better outcome of autograft function., Conclusions: These up to 22 years data show that the subcoronary Ross procedure continues to provide an excellent tissue aortic valve replacement. The suggested valve performance classification emerged as a practical concept for outcome analysis with the probability of 79% being in the favorable class I or II at 20 years., (Copyright © 2018 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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23. A matter of thrombosis: different thrombus-like formations in balloon-expandable transcatheter aortic valve prostheses.
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Richardt D, Haban-Rackebrandt SL, Stock S, Scharfschwerdt M, and Sievers HH
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- Bioprosthesis adverse effects, Hemodynamics, Humans, Prosthesis Design, Prosthesis Failure, Thrombosis physiopathology, Aortic Valve surgery, Heart Valve Prosthesis adverse effects, Thrombosis etiology, Transcatheter Aortic Valve Replacement adverse effects
- Abstract
Objectives: Transcatheter aortic valve implantation is a treatment strategy for degenerated aortic valve prostheses, but there is some concern regarding valve thrombosis. The optimal anticoagulation strategy for implantation of a transcatheter aortic valve prosthesis remains unclear., Methods: Aortic root models with the Sapien-XT and S3 prostheses (sizes 23 and 26) fixed in a Perimount Magna Ease bioprosthesis (sizes 23 and 25) were constructed. The haemodynamics of the left ventricle were imitated in a proved in vitro model. Milk was used for coagulation after 90s. Different areas of the leaflets (W: wall coagulation, C: commissure coagulation left/right and S: sinus coagulation) were examined and the number of thrombus-like formations was counted., Results: A total of 54% of the thrombus-like formations were found in the sinus, 28% at the wall area, 13% at the right commissure and 10% at the left commissure. Significant differences were detected at the wall area. S3 prostheses had significantly more thrombus-like formations than the XT prostheses. Additionally, in the S3 prostheses, the thrombus-like formation resembled a film whereas in the XT prostheses, the thrombus-like formation was like the crumbs of a cake. We noted exactly the same pattern in explanted prostheses from patients., Conclusions: The Sapien prostheses tend to form thromboses due to their flow properties. More than half of the thrombus-like formations were seen in the sinus. The S3 prostheses had significantly more thrombus-like formations than the XT prostheses in the wall area. There are different patterns of thrombus-like formations in XT and S3 prostheses used for transcatheter aortic valve implantation both in vivo and in vitro.
- Published
- 2018
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24. Survival and reoperation pattern after 20 years of experience with aortic valve-sparing root replacement in patients with tricuspid and bicuspid valves.
- Author
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Klotz S, Stock S, Sievers HH, Diwoky M, Petersen M, Stierle U, and Richardt D
- Subjects
- Adult, Aged, Aortic Aneurysm diagnostic imaging, Aortic Aneurysm etiology, Aortic Aneurysm mortality, Aortic Valve diagnostic imaging, Aortic Valve surgery, Bicuspid Aortic Valve Disease, Blood Vessel Prosthesis Implantation adverse effects, Blood Vessel Prosthesis Implantation mortality, Cardiac Surgical Procedures adverse effects, Cardiac Surgical Procedures mortality, Female, Heart Valve Diseases complications, Heart Valve Diseases diagnostic imaging, Heart Valve Diseases mortality, Humans, Male, Middle Aged, Postoperative Complications mortality, Postoperative Complications surgery, Reoperation, Retrospective Studies, Risk Factors, Time Factors, Treatment Outcome, Aortic Aneurysm surgery, Aortic Valve abnormalities, Blood Vessel Prosthesis Implantation methods, Cardiac Surgical Procedures methods, Heart Valve Diseases surgery, Replantation adverse effects, Replantation mortality
- Abstract
Objective: Remodeling or reimplantation are established operative techniques of aortic valve-sparing root replacement. Long-term follow-up is necessary comparing tricuspid and bicuspid aortic valves., Methods: A total of 315 patients (tricuspid, n = 225, bicuspid, n = 89, quadricuspid, n = 1; remodeling, n = 101, reimplantation, n = 214) were evaluated. Mean follow-up was 10.1 ± 5.6 and 6.4 ± 4.2 years for the remodeling and reimplantation group, respectively. Longest follow-up was 21.9 years with 99.2% completeness. Mean age of the patients was 55.9 ± 14.3 for the remodeling group and 48.9 ± 14.5 years for the reimplantation group., Results: There was no significant difference in survival between the remodeling and reimplantation group (P = .11). Survival was comparable with the normal population in the reimplantation group (P = .33). Risk factors for late death were age, diabetes, and a greater New York Heart Association classification. Cumulative incidence of reoperation at 10 years was 5.8% for the reimplantation and 11.7% for the remodeling group (P = .65). Overall, there was no difference in the cumulative incidence of reoperation between tricuspid and bicuspid aortic valve patients (P = .13); however, a landmark analysis showed that in the second decade, the cumulative incidence of reoperation was greater in bicuspid aortic valve patients (P < .001). A total of 10 of 11 reoperated bicuspid aortic valves were degenerated., Conclusions: The remodeling and reimplantation aortic valve-sparing root replacement techniques provided excellent long-term survival. Although the number of patients was relatively small, we provide some hints that in the second decade after the operation, especially in bicuspid aortic valve patients, the risk of reoperation may be increased, needing further evaluation., (Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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25. Mitral valve replacement with the novel TRIBIO and an established stented bioprosthesis in a sheep model.
- Author
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Stock S, Sievers HH, Richardt D, and Scharfschwerdt M
- Subjects
- Animals, Aortic Valve, Echocardiography, Female, Hemodynamics, Models, Animal, Prosthesis Design, Sheep, Bioprosthesis, Heart Valve Prosthesis, Heart Valve Prosthesis Implantation instrumentation, Mitral Valve surgery, Stents
- Abstract
Objectives: Heart valve replacement with a bioprosthesis is one of the most frequently performed procedures in cardiac surgery and represents a highly effective therapy to relieve diseased heart valves. Nevertheless, as postoperatively elevated transvalvular gradients and prosthesis-patient mismatch are reported as shortcomings of the procedure or of the currently used devices, there is a need for novel bioprostheses with improved haemodynamics. This study presents preclinical haemodynamic results after mitral valve replacement with the novel TRIBIO bioprosthesis (TRIBIO) compared with an established bioprosthesis in a sheep model., Methods: Six female sheep had their mitral valves replaced with the TRIBIO and 3 with the Carpentier-Edwards Perimount, both sized 19 mm. The TRIBIO consists of a flexible valve-bearing crown, a force-decoupled interface and an intra-annular base ring. Mean and peak transvalvular gradients as well as an effective orifice area were monitored in both groups using transthoracic echocardiography over the course of the 90-day study., Results: In both groups, haemodynamic performance diminished over time. The TRIBIO demonstrated overall superior haemodynamics, i.e. lower transvalvular gradients and a larger effective orifice area, although the results were not statistically significant. On Day 90, the mean values for the mean and peak transvalvular gradients and the effective orifice area were 6 mmHg, 10.2 mmHg and 1.2 cm2 for the TRIBIO and 10 mmHg, 15.8 mmHg and 0.8 cm2 for the Carpentier-Edwards Perimount, respectively., Conclusions: This study demonstrates a trend towards improved preclinical haemodynamic performance following mitral valve replacement with the TRIBIO compared to that with an established bioprosthesis in a sheep model., (© The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)
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- 2018
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26. Ex vivo hydrodynamics after central and paracommissural edge-to-edge technique: A further step toward transcatheter tricuspid repair?
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Stock S, Bohm H, Scharfschwerdt M, Richardt D, Meyer-Saraei R, Tsvelodub S, and Sievers HH
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- Animals, Hydrodynamics, Recovery of Function, Sus scrofa, Tricuspid Valve physiopathology, Tricuspid Valve Insufficiency physiopathology, Tricuspid Valve Prolapse physiopathology, Cardiac Catheterization methods, Cardiac Surgical Procedures methods, Hemodynamics, Suture Techniques, Tricuspid Valve surgery, Tricuspid Valve Insufficiency surgery, Tricuspid Valve Prolapse surgery
- Abstract
Objectives: Transcatheter approaches in heart valve disease became tremendously important and are currently established in the aortic position, but transcatheter tricuspid repair is still in its beginning and remains challenging. Replicating the surgical edge-to-edge technique, for example, with the MitraClip System (Abbott Vascular, Santa Clara, Calif), represents a promising option and has been reported successfully in small numbers of cases. However, up to now, few data considering the edge-to-edge technique as a transcatheter approach are available. This study aims to determine the ex vivo hydrodynamics after the central and paracommissural edge-to-edge technique in different pathologies., Methods: Because of basal or apical dislocation of papillary muscles, leaflet prolapse or tethering was simulated in porcine tricuspid valves mounted on a flexible holding device. Central and paracommissural edge-to-edge techniques were evaluated successively in these pathologies. Regurgitant volume and mean transvalvular gradient were determined in a pulse duplicator., Results: In this ex vivo model, the isolated edge-to-edge technique reduced tricuspid regurgitation. In the prolapse model, regurgitant volume decreased significantly after central edge-to-edge technique (from 49.4 ± 13.6 mL/stroke to 39.3 ± 14.1 mL/stroke). In the tethering model, both the central and the paracommissural edge-to-edge techniques led to a significant decrease (from 48.7 ± 13.9 to 43.6 ± 15.6 and to 41.1 ± 13.8 mL/stroke). In all cases, the reduction of regurgitant volume was achieved at the cost of significantly increased mean transvalvular gradient., Conclusions: This study provides a reduction of tricuspid regurgitation after the edge-to-edge technique in the specific experimental setup. Whether this reduction is sufficient to treat tricuspid regurgitation successfully in clinical practice remains to be established. Transcatheter approaches need to be evaluated further, probably with regard to concomitant annuloplasty for higher reduction of tricuspid regurgitation., (Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
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- 2018
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27. Rest and exercise haemodynamics in patients with one of two stented bioprostheses and in healthy controls with small aortic annuli.
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Stock S, Lohmann I, Hanke T, Stierle U, Richardt D, Tsvelodub S, and Sievers HH
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- Adult, Aged, Aortic Valve Stenosis pathology, Aortic Valve Stenosis surgery, Case-Control Studies, Echocardiography, Female, Heart Valve Prosthesis Implantation, Humans, Male, Middle Aged, Prosthesis Design, Rest physiology, Aortic Valve Stenosis physiopathology, Bioprosthesis, Exercise physiology, Heart Valve Prosthesis, Hemodynamics physiology, Stents
- Abstract
Objectives: Because bioprosthetic aortic valve replacement remains one of the most frequent cardiac surgical procedures, it is necessary to study patient haemodynamics in more detail. Until now, a few studies assessed haemodynamics during exercise, but none with special regard to small aortic annuli. We compared patients who had the differently designed bioprostheses, Trifecta and Perimount Magna Ease (PME), size ≤ 23 mm, and a healthy control group during rest and exercise., Methods: We determined the mean transvalvular gradient, the effective orifice area (EOA) and the EOA index during rest and exercise using transthoracic echocardiography in 35 patients with the Trifecta (mean age 71.4 years, follow-up 1 year, labelled valve size 21.7 mm), in 16 patients with the PME (mean age 66.2 years, follow-up 2.6 years, labelled valve size 21.6 mm) and in 25 healthy persons. The parameters derived were summarized in a simplified Valve Academic Research Consortium-2 classification to determine prosthetic valve dysfunction., Results: When we compared the Trifecta and the PME, a significant superiority of the Trifecta was seen at rest in mean transvalvular gradient (7.96 vs 12.19 mmHg) and EOA (1.57 vs 1.48 cm2), during exercise in all parameters (mean transvalvular gradient 11.06 vs 19.2 mmHg, EOA 1.77 vs 1.26 cm2, EOA index 0.96 vs 0.67 cm2/m2). The Trifecta showed a physiological increase in the EOA index during exercise. Exercise led to a shift to better simplified Valve Academic Research Consortium-2 categories in the Trifecta and to worse in the PME group., Conclusions: This study reveals the haemodynamic superiority of the Trifecta to the PME. Especially in small aortic annuli, this difference might have some relevance for clinical and research issues., (© The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)
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- 2018
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28. Longer-term results, z scores, and decision nomograms for treatment of the ascending aorta in 1693 bicuspid aortic valve operations.
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Sievers HH, Stock S, Stierle U, Klotz S, Charitos EI, Diwoky M, and Richardt D
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- Adolescent, Adult, Aged, Aged, 80 and over, Aorta diagnostic imaging, Aortic Aneurysm diagnostic imaging, Aortic Aneurysm etiology, Aortic Aneurysm mortality, Aortic Valve diagnostic imaging, Aortic Valve surgery, Bicuspid Aortic Valve Disease, Clinical Decision-Making, Female, Heart Valve Diseases complications, Heart Valve Diseases diagnostic imaging, Heart Valve Diseases mortality, Hospital Mortality, Humans, Male, Middle Aged, Patient Selection, Postoperative Complications mortality, Postoperative Complications surgery, Predictive Value of Tests, Reoperation, Retrospective Studies, Risk Assessment, Risk Factors, Time Factors, Treatment Outcome, Young Adult, Aorta surgery, Aortic Aneurysm surgery, Aortic Valve abnormalities, Blood Vessel Prosthesis Implantation adverse effects, Blood Vessel Prosthesis Implantation mortality, Decision Support Techniques, Heart Valve Diseases surgery, Nomograms
- Abstract
Objective: This study aims to fine-tune the decision making for ascending aorta treatment in bicuspid aortic valve surgery., Methods: A total of 1693 patients with a primary indication for aortic valve surgery were investigated retrospectively with respect to a multifactorial decision-making policy including the z score and the clinical outcome in relation to different techniques for ascending aorta treatment (no intervention n = 1116; intervention n = 577 either by ascending aorta replacement n = 404 or aortoplasty n = 173). Follow-up was 99.5% complete (mean 7.0 ± 4.4 years, range 0-17.7 years, 11,895 patient-years)., Results: Hospital mortality was 1.2% for the no-intervention group and 0.9% for the intervention group and was not different between groups (P = .629). Survival compared with the adjusted normal population was lower for both groups (no intervention: P < .001) but not by such a great margin for the intervention group (P = .27). Determinants for death were not related to the ascending aorta treatment. Aortoplasty led to significantly more reoperations (P = .002). The z score thresholds for intervention on the ascending aorta were greater for younger patients, intervention was more liberal in young age, depicted in nomograms., Conclusions: In our study, ascending aorta intervention could be performed with low hospital mortality and obviously did not add to the overall mortality compared with no intervention. Ascending aorta replacement was the most definite intervention. The multifactorial decision for ascending aorta intervention including the z score of the ascending aorta was more liberal in younger patients compared to the simple aortic size guidelines and provided excellent results. However, generalizability needs further data., (Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
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- 2018
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29. First ex vivo and preliminary sheep model results of the new TRIBIO aortic valve bioprosthesis in small aortic annuli.
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Stock S, Sievers HH, Richardt D, and Scharfschwerdt M
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- Aged, Animals, Aortic Valve diagnostic imaging, Aortic Valve Stenosis diagnosis, Disease Models, Animal, Heart Rate, Humans, Postoperative Period, Prosthesis Design, Sheep, Swine, Aortic Valve surgery, Aortic Valve Stenosis surgery, Bioprosthesis, Heart Valve Prosthesis
- Abstract
Objectives: Small aortic annuli are challenging in aortic valve replacement. Prosthesis-patient mismatch, accompanied by high transvalvular gradients and small orifice area, is an often faced problem impairing postoperative outcome. The new TRIBIO bioprosthesis aims to enable enhanced haemodynamics, being increasingly important with decreasing annular size. This study compares ex vivo hydrodynamics of TRIBIO with 2 established bioprostheses in small annuli at different stroke volumes, simulating 'rest' and 'exercise', and evaluates haemodynamics of TRIBIO in a sheep model., Methods: Ex vivo: Porcine aortic roots were hardened with glutaraldehyde, approaching the stiffness of decalcified roots. Each bioprosthesis (TRIBIO, Trifecta™, Perimount® Magna Ease), size 19 mm, was implanted in each aortic root and inserted into a pulse duplicator, determining hydrodynamics and geometric orifice area at different stroke volumes (74, 90, 104 ml). Sheep model: Postoperative transvalvular gradients were assessed after implantation of 19 mm TRIBIO in aortic position., Results: Ex vivo: Mean transvalvular gradients were lowest in TRIBIO (7.3, 8.7, 10.2 mmHg at 74, 90, 104 ml) with significant difference to Perimount® Magna Ease. Geometric orifice area in TRIBIO was 2.7 cm2 and significantly larger compared to Perimount® Magna Ease and Trifecta™. Opening of TRIBIO was uniform and apparently complete, whereas leaflet's outward movement was restricted particularly in Perimount® Magna Ease. Sheep model: TRIBIO presented with low transvalvular gradients (δpmean 4.1 ± 2 mmHg, δpmax 7.8 ± 4.6 mmHg), unimpaired leaflet motion and no central or paravalvular leakage., Conclusions: Ex vivo, the TRIBIO achieved superior hydrodynamics compared to latest generation bioprostheses. These excellent data are supported by very low transvalvular gradients in a preliminary sheep model., (© The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)
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- 2017
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30. Long-Term (up to 21 Years) Follow Up after Biological and Mechanical Aortic Valve Replacement in Younger Patients.
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Tsvelodub S, Pieper B, Stock S, Sievers HH, and Richardt D
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- Adult, Female, Follow-Up Studies, Germany epidemiology, Heart Valve Diseases epidemiology, Humans, Male, Middle Aged, Postoperative Period, Reoperation methods, Reoperation statistics & numerical data, Aortic Valve diagnostic imaging, Aortic Valve pathology, Aortic Valve physiopathology, Aortic Valve surgery, Bioprosthesis adverse effects, Bioprosthesis statistics & numerical data, Heart Valve Diseases surgery, Heart Valve Prosthesis adverse effects, Heart Valve Prosthesis statistics & numerical data, Heart Valve Prosthesis Implantation adverse effects, Heart Valve Prosthesis Implantation instrumentation, Heart Valve Prosthesis Implantation methods, Long Term Adverse Effects diagnosis, Long Term Adverse Effects epidemiology, Long Term Adverse Effects etiology, Postoperative Complications diagnosis, Postoperative Complications epidemiology, Postoperative Complications etiology, Postoperative Complications surgery
- Abstract
Background: Despite the limited durability of biological aortic valves, increasing numbers of younger patients are choosing to receive them, due mainly to the lack of a need for permanent anticoagulation. Few data exist, however, regarding the outcomes of valve replacement in patients aged <55 years, and additional data are required in this patient population., Methods: Between 1993 and 2014, at the authors' institution, a total of 448 patients (237 males, 101 females; mean age 45.8 ± 8.0 years) underwent aortic valve replacement (AVR) with either a mechanical prosthesis (M1 group, n = 318) or a biological prosthesis (B1 group, n = 130). The mean follow up was 8.5 ± 5.8 years (range: 4 days to 20.8 years) in the M1 group, and 4.9 ± 4.6 years (range: 2 days to 21 years) in the B1 group. The entire collective (EC) (n = 448 patients) was compared and analyzed with a selective collective (SC) (n = 109 patients) after exclusion of patients with concomitant procedures or comorbidities (M2 group, n = 74; B2 group, n = 35)., Results: Early mortality was greater after biological AVR in the EC (6.1% versus 1.9%), but in the SC no early deaths were observed after both primary and redo procedures. The reoperation rate was greater after biological AVR in both collectives. The late mortality, survival and endocarditis rates were comparable in both collectives. Bleeding occurred more often in the EC after mechanical AVR., Conclusions: Biological AVR in patients aged <55 years provides satisfactory outcomes, whereas reoperations were performed less commonly in patients with mechanical valve substitutes. In selective patients, AVR can be performed with zero mortality.
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- 2017
31. Does Undersizing of Transcatheter Aortic Valve Bioprostheses during Valve-in-Valve Implantation Avoid Coronary Obstruction? An In Vitro Study.
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Stock S, Scharfschwerdt M, Meyer-Saraei R, Richardt D, Charitos EI, Sievers HH, and Hanke T
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- Aortic Valve physiopathology, Balloon Valvuloplasty, Coronary Circulation, Coronary Stenosis etiology, Coronary Stenosis physiopathology, Heart Valve Prosthesis Implantation adverse effects, Hemodynamics, Humans, Hydrodynamics, Materials Testing, Models, Anatomic, Models, Cardiovascular, Prosthesis Design, Risk Factors, Transcatheter Aortic Valve Replacement adverse effects, Aortic Valve surgery, Bioprosthesis, Coronary Stenosis prevention & control, Heart Valve Prosthesis, Heart Valve Prosthesis Implantation instrumentation, Prosthesis Failure, Transcatheter Aortic Valve Replacement instrumentation
- Abstract
Background The transcatheter aortic valve-in-valve implantation (TAViVI) is an evolving treatment strategy for degenerated surgical aortic valve bioprostheses (SAVBs) in patients with high operative risk. Although hemodynamics is excellent, there is some concern regarding coronary obstruction, especially in SAVB with externally mounted leaflet tissue, such as the Trifecta (St. Jude Medical Inc., St. Paul, Minnesota, United States). We investigated coronary flow and hydrodynamics before and after TAViVI in a SAVB with externally mounted leaflet tissue (St. Jude Medical, Trifecta) with an undersized transcatheter aortic valve bioprosthesis (Edwards Sapien XT; Edwards Lifesciences LLC, Irvine, California, United States) in an in vitro study. Materials and Methods An aortic root model was constructed incorporating geometric dimensions known as risk factors for coronary obstruction. Investigating the validity of this model, we primarily performed recommended TAViVI with the Sapien XT (size 26 mm) in a Trifecta (size 25 mm) in a mock circulation. Thereafter, hydrodynamic performance and coronary flow (left/right coronary diastolic flow [lCF/rCF]) after TAViVI with an undersized Sapien XT (size 23 mm) in a Trifecta (size 25 mm) were investigated at two different coronary ostia heights (COHs, 8 and 10 mm). Results Validation of the model led to significant coronary obstruction ( p < 0.001). Undersized TAViVI showed no significant reduction with respect to coronary flow (lCF: COH 8 mm, 0.90-0.87 mL/stroke; COH 10 mm, 0.89-0.82 mL/stroke and rCF: COH 8 mm, 0.64-0.60 mL/stroke; COH 10 mm, 0.62-0.58 mL/stroke). Mean transvalvular gradients (4-5 mm Hg, p < 0.001) increased significantly after TAViVI. Conclusions In our in vitro model, undersized TAViVI with the balloon-expandable Sapien XT into a modern generation SAVB (Trifecta) successfully avoided coronary flow obstruction., (Georg Thieme Verlag KG Stuttgart · New York.)
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- 2017
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32. In vitro coronary flow after transcatheter aortic valve-in-valve implantation: A comparison of 2 valves.
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Stock S, Scharfschwerdt M, Meyer-Saraei R, Richardt D, Charitos EI, Sievers HH, and Hanke T
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- Aortic Valve physiopathology, Aortic Valve Stenosis physiopathology, Calcinosis physiopathology, Humans, Prosthesis Design, Aortic Valve pathology, Aortic Valve surgery, Aortic Valve Stenosis surgery, Bioprosthesis, Calcinosis surgery, Coronary Circulation physiology, Coronary Vessels physiopathology, Heart Valve Prosthesis, Regional Blood Flow physiology, Transcatheter Aortic Valve Replacement methods
- Abstract
Background: Transcatheter aortic valve-in-valve implantation (TAVI-ViV) is an evolving treatment strategy for degenerated surgical aortic valve bioprostheses (SAVBs). However, there is some concern regarding coronary obstruction, especially after TAVI-ViV in calcified SAVBs with externally mounted leaflets. We investigated in vitro coronary flow and hydrodynamics after TAVI-ViV using 2 modern SAVBs with externally and internally mounted leaflets., Methods: Aortic root models including known risk factors for coronary obstruction served for the implantation of SAVBs with either externally mounted leaflets (St Jude Trifecta, size 25) or internally mounted leaflets (Edwards Perimount Magna Ease, size 25). Left and right coronary flow, as well as hydrodynamic parameters, were measured before and after TAVI-ViV with an Edwards Sapien XT transcatheter heart valve, size 23. After the first experimental run, the SAVB leaflets were artificially "calcified," and the measurements were repeated., Results: In both models, noncalcified and calcified, there was no significant reduction in coronary flow with either the Trifecta or the Perimount Magna Ease SAVB. After TAVI-ViV, in the noncalcified model, the mean pressure gradient was increased (Trifecta, P = .0001; Perimount Magna Ease, P = .006) and the geometric orifice area was decreased (P < .001 for both), whereas in the calcified model, the mean pressure gradient was decreased (P < .001 for both) and the geometric orifice area was increased (P < .001 for both)., Conclusions: In our specific model, in noncalcified as well as calcified conditions, TAVI-ViV is feasible with either SAVB (Trifecta or Perimount Magna Ease) without an increased risk of coronary obstruction. Nevertheless, before clinical application of these results, thorough preoperative assessment, considering the different limitations of this model, is mandatory., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
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- 2017
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33. Time-resolved 3-dimensional magnetic resonance phase contrast imaging (4D Flow MRI) analysis of hemodynamics in valve-sparing aortic root repair with an anatomically shaped sinus prosthesis.
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Oechtering TH, Hons CF, Sieren M, Hunold P, Hennemuth A, Huellebrand M, Drexl J, Scharfschwerdt M, Richardt D, Sievers HH, Barkhausen J, and Frydrychowicz A
- Subjects
- Adult, Aged, Aorta diagnostic imaging, Aorta physiopathology, Aortic Valve diagnostic imaging, Aortic Valve physiopathology, Blood Flow Velocity, Blood Vessel Prosthesis Implantation adverse effects, Case-Control Studies, Female, Humans, Image Interpretation, Computer-Assisted, Male, Middle Aged, Models, Cardiovascular, Patient-Specific Modeling, Predictive Value of Tests, Regional Blood Flow, Time Factors, Treatment Outcome, Young Adult, Aorta surgery, Blood Vessel Prosthesis, Blood Vessel Prosthesis Implantation instrumentation, Hemodynamics, Magnetic Resonance Imaging, Perfusion Imaging methods, Prosthesis Design
- Abstract
Objective: The anatomically shaped sinus prosthesis (Uni-Graft W SINUS; Braun, Melsungen, Germany) used in valve-sparing aortic root replacement promises physiological hemodynamics believed to grant physiologic valve function. Using time-resolved 3-dimensional magnetic resonance phase contrast imaging (4D Flow MRI), we analyzed sinus vortex formation and transvalvular pressure gradients in patients with sinus prosthesis compared with age-matched and young healthy volunteers., Methods: Twelve patients with sinus prosthesis (55 ± 15 years), 12 age-matched and 6 young healthy volunteers (55 ± 6 years, 25 ± 3 years, respectively) were examined at 3T with a 4D flow magnetic resonance imaging sequence. Sinus vortices visualized by streamlines and time-resolved particle paths were graded on a 4-point Likert scale. Time resolved pressure differences of the left ventricular outflow tract and the ascending aorta to a reference point in the aortic bulb as well as the transvalvular pressure gradient were evaluated., Results: 4D flow visualizations revealed a propensity of the sinus prosthesis toward intermediate (50%) and large (28%) vortices compared with age-matched volunteers with small (61%) and intermediate (36%) vortices. Vortices in sinus prostheses had a similar configuration compared with those in volunteers. The peak transvalvular pressure gradient did not vary significantly between patients and age-matched volunteers (4.0 ± 0.9 mm Hg, 3.8 ± 0.7 mm Hg, P = .373), its temporal evolution resembled that of volunteers with a prolonged positive phase in patients., Conclusions: Hemodynamics closely relating to those of volunteers were confirmed in sinus prostheses, believed to grant physiological valve function. Minor differences are presumably attributed to graft compliance and temporal resolution of the acquisition. Nevertheless, long-term deterioration of valve function as it was described for straight grafts could potentially be decelerated using sinus prostheses., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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34. Is the outcome in acute aortic dissection type A influenced by of femoral versus central cannulation?
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Klotz S, Bucsky BS, Richardt D, Petersen M, and Sievers HH
- Abstract
Background: The purpose of this study was to evaluate the single-center experience in initial femoral versus central cannulation of the extracorporeal circulation for acute aortic dissection type A (AADA)., Methods: Between January 2003 and December 2015, 235 patients underwent repair of AADA. All patients were evaluated for the type of arterial cannulation (femoral vs. central) for initial bypass. Demographic data and outcome parameters were accessed., Results: One hundred and twenty seven (54.0%) were initially cannulated in the central aortic vessels (ascending aorta or subclavian/axillary artery) and 108 (46.0%) in the femoral artery. Patients were comparable between age (62.4±14.4 vs. 62.9±14.4 years, P=0.805), gender (male, 62.2 vs. 69.4%, P=0.152) and previous sternotomy (15.7 vs. 16.7%, P=0.861) between both cannulation groups; while EuroSCORE I (11.5±4.0 vs. 12.7±4.2, P=0.031) and ASA Score (3.5±0.81 vs. 3.8±0.57, P=0.011) were significantly higher in the femoral artery cannulation group. Bypass (249±102 vs. 240±81 min, P=0.474), X-clamp (166±85 vs. 157±67 min, P=0.418) and circulatory arrest time (51.6±28.7 vs. 48.3±21.7 min, P=0.365) were similar between the groups as were lowest temperature (18.1±2.0 vs. 18.1±2.2, P=0.775). Postoperative neurologic deficit and 30-day mortality were comparable between both cannulation groups (11.7 vs. 7.2%, P=0.449 and 20.2 vs. 16.9%, P=0.699, central vs. peripheral cannulation). Multivariate analysis revealed only EuroScore I above 13 as single preoperative predictor for mortality., Conclusions: AADA can be operated with both femoral and central cannulation with similar results. Risk for early mortality was driven by the preoperative clinical and hemodynamic status before operation rather than the cannulation technique.
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- 2016
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35. In vitro investigation of a novel elastic vascular prosthesis for valve-sparing aortic root and ascending aorta replacement.
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Scharfschwerdt M, Leonhard M, Lehmann J, Richardt D, Goldmann H, and Sievers HH
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- Animals, Blood Pressure, Elasticity, Materials Testing, Models, Cardiovascular, Prosthesis Design, Swine, Aorta surgery, Aortic Valve surgery, Blood Vessel Prosthesis Implantation instrumentation, Heart Valve Prosthesis, Polyurethanes chemistry
- Abstract
Objectives: Prosthetic replacement of the thoracic aorta with common Dacron prostheses impairs the aortic 'windkessel' and, in valve-sparing procedures, also aortic valve function. Elastic graft material may overcome these deficiencies., Methods: Fresh porcine aortas including the root were set up in a mock circulation before and after replacement of the ascending part with a novel vascular prosthesis providing elastic behaviours. In a first series (n = 14), haemodynamics and leaflet motions of the aortic valve were investigated and also cyclic changes of aortic dimensions at different levels of the root. In a second series (n = 7), intravascular pressure and dimensions of the proximal descending aorta were measured and the corresponding wall tension was calculated., Results: Haemodynamics of the aortic valve remain comparable after replacement. Though the novel prosthesis does not feature such high distensibility as the native aorta, the dynamic of the root was significantly increased compared with common Dacron prostheses at the commissural level, preserving 'windkessel' function. Thus, wall tension of the residual aorta remained unchanged; nevertheless, maximum pressure-time differential dp/dt increased by 13%., Conclusions: The use of the novel elastic prosthesis for replacement of the ascending aorta seems to be beneficial, especially with regard to the preservation of the aortic windkessel. Further studies will be needed to clarify long-term utilization of the material in vivo., (© The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)
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- 2016
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36. Survival and freedom from aortic valve-related reoperation after valve-sparing aortic root replacement in 1015 patients.
- Author
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Kari FA, Doll KN, Hemmer W, Liebrich M, Sievers HH, Richardt D, Reichenspurner H, Detter C, Siepe M, Czerny M, and Beyersdorf F
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- Adult, Aged, Aortic Aneurysm diagnosis, Aortic Aneurysm mortality, Aortic Valve Insufficiency diagnosis, Aortic Valve Insufficiency mortality, Disease-Free Survival, Female, Germany, Humans, Kaplan-Meier Estimate, Logistic Models, Male, Middle Aged, Multivariate Analysis, Proportional Hazards Models, Reoperation, Retrospective Studies, Risk Factors, Time Factors, Treatment Outcome, Aorta surgery, Aortic Aneurysm surgery, Aortic Valve surgery, Aortic Valve Insufficiency surgery, Blood Vessel Prosthesis Implantation adverse effects, Blood Vessel Prosthesis Implantation mortality, Heart Valve Prosthesis Implantation adverse effects, Heart Valve Prosthesis Implantation mortality, Replantation adverse effects, Replantation mortality
- Abstract
Objectives: The aim of this study was to characterize mortality and aortic valve replacement after valve-sparing aortic root replacement (V-SARR) in a multicentre cohort., Methods: Between 1994 and 2014, 1015 patients had V-SARR with (n = 288, 28%) or without cusp/commissure repair (n = 727, 72%) at the centres of Lübeck (n = 343, 34%), Stuttgart (n = 346, 34%), Hamburg (n = 109, 11%) and Freiburg (n = 217, 21%), Germany. Comparative survival of an age- and gender-matched general population was calculated. Log-rank tests and multiple logistic regression were used to identify risk factors., Results: The mean follow-up was 5.2 ± 3.9 years. Cumulative follow-up comprised 2933 patient-years. Early survival was 98%. NYHA status and aneurysm size were predictive of death during mid-term follow-up (P = 0.025). Freedom from aortic valve replacement was 90% at 8 years, with the type of V-SARR (root remodelling, David II) being a risk factor (P = 0.015). Bicuspid aortic valve (P = 0.26) and initial valve function (P = 0.4) did not impact reoperation. The need of additional valve repair (cusps/commissures) was not linked to reoperation: freedom from aortic valve replacement at 8 years was 84% if cusp repair was performed versus 90% if V-SARR alone was performed (P = 0.218). Marfan syndrome had no impact on survival or on aortic valve replacement., Conclusions: Mid-term survival of patients after V-SARR is comparable with that of a matched general population. The regurgitant bicuspid aortic valve is a favourable substrate for V-SARR. Prophylactic surgery should be performed before symptoms or large aneurysms are present to achieve optimal mid-term outcomes., (© The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)
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- 2016
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37. Residual and Progressive Aortic Regurgitation After Valve-Sparing Root Replacement: A Propensity-Matched Multi-Institutional Analysis in 764 Patients.
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Kari FA, Doll KN, Hemmer W, Liebrich M, Sievers HH, Richardt D, Reichenspurner H, Detter C, Siepe M, Czerny M, and Beyersdorf F
- Subjects
- Adult, Aged, Aorta, Thoracic surgery, Aortic Valve surgery, Aortic Valve Insufficiency diagnostic imaging, Aortic Valve Insufficiency mortality, Blood Vessel Prosthesis Implantation adverse effects, Case-Control Studies, Disease Progression, Echocardiography methods, Female, Follow-Up Studies, Germany, Heart Valve Prosthesis Implantation methods, Humans, Logistic Models, Male, Middle Aged, Multivariate Analysis, Propensity Score, Recurrence, Reoperation methods, Replantation methods, Retrospective Studies, Risk Assessment, Severity of Illness Index, Statistics, Nonparametric, Survival Rate, Treatment Outcome, Aortic Valve Insufficiency surgery, Blood Vessel Prosthesis Implantation methods, Cardiac Valve Annuloplasty methods, Heart Valve Prosthesis Implantation adverse effects, Organ Sparing Treatments methods
- Abstract
Background: Residual/progressive aortic regurgitation (rAR, pAR) after valve-sparing aortic root replacement (V-SARR) can lead to reoperations. We sought to characterize risk factors of mild rAR and pAR after V-SARR in a multicenter cohort. The effect of additional cusp repair on valve function was analyzed using propensity matching., Methods: A total of 1,015 patients after V-SARR were identified with (n = 288, 28%) or without additional cusp/commissure repair (n = 727, 72%) at four cardiac units in Germany. A total of 764 patients fulfilling transthoracic echocardiography follow-up-criteria comprised the study cohort. Logistic regression was used for risk factor analysis with endpoints rAR, new onset AR, and pAR. t tests and analyses of variance were used for between-group differences. The effects of additional cusp repair on valve function were studied comparing propensity-matched quintiles., Results: The incidence of rAR was 29%, with influencing factors aneurysm size (p = 0.07) and preoperative aortic valve function (p = 0.08). It was found more often among nonsyndromic patients (34% vs. 14%; OR, 0.4; p < 0.001). Progression of rAR was detectable in 30% after a mean of 4.3 years. The progression rate of rAR ∼ 0.3 grades per patient-year within the first 5 years. When quintiles identified by propensity score were compared, additional cusp repair was linked to new onset AR (p = 0.016) while it was not linked to rAR (p = 0.14) or pAR (p = 0.5)., Conclusions: The incidences of rAR and pAR are considerable after V-SARR. Patients should be operated on before large aneurysms are present. New onset AR after an initially good functional result is more likely after an additional cusp repair, while rAR and pAR are not influenced by cusp repair., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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38. Acute kidney injury after transcatheter aortic valve implantation: Impact of contrast agents, predictive factors, and prognostic importance in 203 patients with long-term follow-up.
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Chatani K, Abdel-Wahab M, Wübken-Kleinfeld N, Gordian K, Pötzing K, Mostafa AE, Kraatz EG, Richardt D, El-Mawardy M, and Richardt G
- Subjects
- Acute Kidney Injury blood, Acute Kidney Injury mortality, Aged, Aged, 80 and over, Aortic Valve Stenosis blood, Contrast Media chemistry, Creatinine blood, Female, Follow-Up Studies, Humans, Male, Odds Ratio, Osmolar Concentration, Prognosis, Risk Factors, Time Factors, Acute Kidney Injury etiology, Aortic Valve Stenosis surgery, Cardiac Catheterization adverse effects, Contrast Media adverse effects, Transcatheter Aortic Valve Replacement adverse effects
- Abstract
Background: Acute kidney injury (AKI) frequently occurs following transcatheter aortic valve implantation (TAVI) and has been related to a worse outcome. We investigated the importance of contrast medium composition, either iso-osmolar (IOCM) or low-osmolar (LOCM) and assessed predictors for AKI after TAVI., Methods and Results: We assessed AKI in 203 TAVI patients treated mainly with trans-femoral implantation and analgosedation. A total of 100 patients received IOCM and 103 LOCM. AKI was defined according to the Valve Academic Research Consortium. Following TAVI, 39 patients (19.2%) developed AKI; 17.0% of the IOCM and 21.4% of the LOCM group (p=0.43). The only independent predictor for AKI was baseline serum creatinine [odds ratio (OR) 0.26, 95% confidence interval (CI) 0.01-0.64, p=0.002]. Patients with advanced AKI (stages 2 and 3) post-TAVI had significantly higher mortality at 2 years (log rank p<0.001), whereas patients with AKI stage 1 had a similar long-term outcome to non-AKI patients., Conclusions: Following TAVI, we observed no difference in the occurrence of AKI between IOCM and LOCM. Baseline creatinine was the only independent predictor of AKI, and patients who developed advanced AKI had significantly higher mortality at 2 years., (Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2015
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39. 1-Year Outcomes After Transcatheter Aortic Valve Replacement With Balloon-Expandable Versus Self-Expandable Valves: Results From the CHOICE Randomized Clinical Trial.
- Author
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Abdel-Wahab M, Neumann FJ, Mehilli J, Frerker C, Richardt D, Landt M, Jose J, Toelg R, Kuck KH, Massberg S, Robinson DR, El-Mawardy M, and Richardt G
- Subjects
- Aged, Aged, 80 and over, Balloon Valvuloplasty standards, Female, Follow-Up Studies, Heart Valve Prosthesis standards, Humans, Male, Middle Aged, Prospective Studies, Prosthesis Design standards, Time Factors, Transcatheter Aortic Valve Replacement standards, Treatment Outcome, Aortic Valve Stenosis diagnosis, Aortic Valve Stenosis surgery, Balloon Valvuloplasty trends, Heart Valve Prosthesis trends, Prosthesis Design trends, Transcatheter Aortic Valve Replacement trends
- Abstract
Background: The use of a balloon-expandable transcatheter heart valve previously resulted in a greater rate of device success compared with a self-expandable transcatheter heart valve., Objectives: The aim of this study was to evaluate clinical and echocardiographic outcome data at longer term follow-up., Methods: The investigator-initiated trial randomized 241 high-risk patients with symptomatic severe aortic stenosis and anatomy suitable for treatment with both balloon- and self-expandable transcatheter heart valves to transfemoral transcatheter aortic valve replacement with either device. Patients were followed-up for 1 year, with assessment of clinical outcomes and echocardiographic evaluation of valve function., Results: At 1 year, the rates of death of any cause (17.4% vs. 12.8%; relative risk [RR]: 1.35; 95% confidence interval [CI]: 0.73 to 2.50; p = 0.37) and of cardiovascular causes (12.4% vs. 9.4%; RR: 1.32; 95% CI: 0.63 to 2.75; p = 0.54) were not statistically significantly different in the balloon- and self-expandable groups, respectively. The frequencies of all strokes (9.1% vs. 3.4%; RR: 2.66; 95% CI: 0.87 to 8.12; p = 0.11) and repeat hospitalization for heart failure (7.4% vs. 12.8%; RR: 0.58; 95% CI: 0.26 to 1.27; p = 0.19) did not statistically significantly differ between the 2 groups. Elevated transvalvular gradients during follow-up were observed in 4 patients in the balloon-expandable group (3.4% vs. 0%; p = 0.12); all were resolved with anticoagulant therapy, suggesting a thrombotic etiology. More than mild paravalvular regurgitation was more frequent in the self-expandable group (1.1% vs. 12.1%; p = 0.005)., Conclusions: Despite the higher device success rate with the balloon-expandable valve, 1-year follow-up of patients in CHOICE (Randomized Comparison of Transcatheter Heart Valves in High Risk Patients With Severe Aortic Stenosis: Medtronic CoreValve Versus Edwards SAPIEN XT Trial), with limited statistical power, revealed clinical outcomes after transfemoral transcatheter aortic valve replacement with both balloon- and self-expandable prostheses that were not statistically significantly different. (A Comparison of Transcatheter Heart Valves in High Risk Patients With Severe Aortic Stenosis: The CHOICE Trial; NCT01645202)., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)
- Published
- 2015
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40. Two cases of heart failure after implantation of a CoreValve prosthesis.
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Richardt D, Hanke T, and Sievers HH
- Subjects
- Aged, Aged, 80 and over, Aortic Valve Stenosis surgery, Female, Heart Valve Prosthesis Implantation, Humans, Prosthesis Design, Heart Failure etiology, Heart Valve Prosthesis adverse effects
- Published
- 2015
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41. Age-related reoperation rate after the Ross procedure: a report from the German Ross Registry.
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Richardt D, Hemmer W, Moritz A, Hetzer R, Gorski A, Franke UF, Hörer J, Lange R, Sachweh JS, Riso A, Dodge-Khatami A, Hübler M, Charitos EI, Stierle U, and Sievers HH
- Subjects
- Adult, Bioprosthesis, Female, Germany, Heart Valve Diseases physiopathology, Humans, Male, Middle Aged, Registries, Reoperation statistics & numerical data, Young Adult, Cardiac Surgical Procedures, Heart Valve Diseases surgery
- Abstract
Background and Aim of the Study: An increasing number of young adult patients are choosing bioprostheses for aortic valve replacement (AVR). In this context, the Ross operation deserves renewed consideration as an alternative biological substitute. After both the Ross procedure and bioprosthetic AVR, reoperation rates remain a concern and may be related to age at surgery. Herein are reported details of freedom from reoperation after the Ross procedure for different age groups., Methods: The reoperation rates of 1,925 patients (1,444 males, 481 females; mean age 41.2 ± 15.3 years) from the German Ross registry with a mean follow up of 7.4 ± 4.7 years (range: 0.00-18.51 years; total 12,866.6 patient-years) were allocated to three age groups: group I < 40 years; group II 40-60 years; and group III > 60 years., Results: At 10 years (respectively 15 years) of follow up, freedom from reoperation was 86% (76%) in group I, 93% (85%) in group II, and 89% (83%) in group III., Conclusion: There is some evidence that, at least during the first 10 and 15 years after AVR, the Ross procedure provides a significantly lower reoperation rate in young adult and middle-aged patients aged < 60 years. This information may be of interest to the patients' or physicians' decision-making for aortic valve surgery.
- Published
- 2015
42. Long-Term Results after Aortic Valve-Sparing-Reimplantation Operation (David) in Bicuspid Aortic Valve.
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Richardt D, Stierle U, and Sievers HH
- Subjects
- Adult, Aortic Valve diagnostic imaging, Aortic Valve physiopathology, Aortic Valve surgery, Aortic Valve Insufficiency diagnostic imaging, Aortic Valve Insufficiency etiology, Aortic Valve Insufficiency physiopathology, Aortic Valve Prolapse etiology, Aortic Valve Prolapse surgery, Bicuspid Aortic Valve Disease, Female, Germany, Heart Valve Diseases complications, Heart Valve Diseases diagnostic imaging, Heart Valve Diseases physiopathology, Hemodynamics, Humans, Male, Middle Aged, Reoperation, Retrospective Studies, Time Factors, Treatment Outcome, Ultrasonography, Aortic Valve abnormalities, Aortic Valve Insufficiency surgery, Cardiac Surgical Procedures adverse effects, Heart Valve Diseases surgery, Replantation adverse effects
- Abstract
Background and Aim of the Study: The aortic valve-sparing reimplantation operation (David) is increasingly used in patients with aortic root aneurysm and intact cusps. David's procedure is also feasible in patients with bicuspid aortic valve (BA), though few long-term data are available., Methods: An analysis was conducted of the long-term echocardiographic data from patients with BAV who had undergone David's procedure at early and long-term follow up (FU) examinations., Results: Between 1994 and 2010, a total of 30 patients with BAV underwent David's procedure at the authors'institution. There were no in-hospital or late deaths, and the mean long-term FU was 6.64 ± 3.54 years (range: 3.2-20.1 years). The mean aortic regurgitation (AR) grade was increased from 0.26 ± 0.37 at early FU to 0.70 ± 0.80 at long-term FU (p = 0.013). Four patients (13%) had to be reoperated after 10.00 ± 4.74 years (range: 5.49-17.06 years) due to aortic stenosis (n = 1) and aortic insufficiency (n = 3); the latter three patients had a significant prolapse of both the fused and the non-coronary cusp of reconstruction., Conclusion: The mean AR grade was increased significantly but was ≤ I-II in 59% of patients and ≤ II in 93% of patients after a mean FU of 6.6 years. Patients with prolapsing non-coronary leaflet at reconstruction seemed vulnerable to recurrent AR. Among patients, survival was excellent, and the reoperation rate and hemodynamics acceptable. Long-term follow up data are necessary to further refine the surgical techniques employed and to improve the results achieved.
- Published
- 2015
43. Toward individualized management of the ascending aorta in bicuspid aortic valve surgery: the role of valve phenotype in 1362 patients.
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Sievers HH, Stierle U, Mohamed SA, Hanke T, Richardt D, Schmidtke C, and Charitos EI
- Subjects
- Adult, Aged, Aortic Aneurysm diagnosis, Aortic Aneurysm etiology, Aortic Aneurysm mortality, Aortic Valve surgery, Bicuspid Aortic Valve Disease, Decision Support Techniques, Female, Heart Valve Diseases complications, Heart Valve Diseases diagnosis, Heart Valve Diseases mortality, Hospital Mortality, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Phenotype, Postoperative Complications mortality, Postoperative Complications surgery, Proportional Hazards Models, Reoperation, Retrospective Studies, Risk Assessment, Risk Factors, Time Factors, Treatment Outcome, Aortic Aneurysm surgery, Aortic Valve abnormalities, Blood Vessel Prosthesis Implantation adverse effects, Blood Vessel Prosthesis Implantation mortality, Cardiac Surgical Procedures adverse effects, Cardiac Surgical Procedures mortality, Heart Valve Diseases surgery, Patient Selection, Precision Medicine
- Abstract
Objective: Decision making regarding the management of the ascending aorta (AA) in patients with a bicuspid aortic valve (BAV) undergoing valve surgery has hardly been individualized and remains controversial. We analyzed our individualized, multifactorial approach, focusing on the BAV phenotype., Methods: In 1362 patients (1044 men) undergoing aortic valve surgery, the BAV phenotypes were intraoperatively classified and retrospectively analyzed. The mean follow-up was 5.4±3.6 years (range, 0-14; 7334 patient-years), and the data were 96.5% complete. The individualized AA management decision process mainly included the AA diameter, age, body surface area, macroscopic AA configuration, and the perceived tissue strength of the aortic wall resulting in 3 AA treatment groups: no intervention, aortoplasty (AoP), and AA replacement (AAR)., Results: In 906 patients (66.5%), no intervention was performed and 172 (12.6%) and 284 (20.9%) underwent AoP and AAR, respectively. The hospital mortality was 1.1% for no intervention, 0.6% for AoP, and 0.4% for AAR (P=.4). The 10-year survival was similar for all 3 groups and comparable to that of the general population. Five reoperations on the AA occurred, 4 in the no intervention and 1 in the AoP group. BAV type 2/unicuspid patients were younger and more had undergone AAR in absolute numbers and after allowing for the AA diameter. Also, in patients with BAV type 1 LR and regurgitation, AAR was performed more often., Conclusions: The individualized, multifactorial management of AA in patients with BAV during aortic valve surgery leads to excellent results. The threshold AA diameter for intervention (AoP or AAR) varied from 34 to 51 mm (mean, 43.9). BAV type 2/unicuspid and BAV type 1 LR with regurgitation emerged as determinants for more liberal AAR in our practice. Longer term follow-up is necessary to confirm our conclusions., (Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2014
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44. A novel rigid annuloplasty ring for aortic valve reconstruction: an in vitro investigation.
- Author
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Richardt D, Bucsky B, Charitos EI, Sievers HH, and Scharfschwerdt M
- Subjects
- Animals, In Vitro Techniques, Prosthesis Design, Swine, Aortic Valve surgery, Cardiac Valve Annuloplasty instrumentation
- Abstract
Background: Remodeling of the dilated valve annulus with a prosthetic ring for repair of valve insufficiency is a well-established concept in mitral and tricuspid valve surgery and may also be suitable for aortic valve reconstruction. A novel rigid aortic annuloplasty ring was tested in vitro., Methods: Ten fresh porcine aortic roots were investigated in a pulsatile flow simulator before surgery (group N), after patch dilatation of the annulus (group D), and after reconstruction using a rigid annuloplasty ring (group R). The ring was designed to (1) prevent contact with the leaflets, reducing the risk of contact injury, (2) be applicable to all valve phenotypes, (3) prevent injury to the conduction bundle, and (4) be implantable from inside the aortic root (subvalvular). For each group pressure gradient, leakage volume, and coaptation height were measured., Results: With the annuloplasty ring, regurgitation volume decreased from -8.50 ± 1.91 mL (group D) to -4.75 ± 1.66 mL (group R; p < 0.0003), not different from group N. Coaptation height of the leaflets increased from 0.62 ± 0.08 mm (group D) to 0.77 ± 0.11 mm (group R; p < 0.005), similar to group N. Mean pressure gradient increased from 2.98 ± 0.38 mm Hg (group D) to 3.72 ± 0.40 mm Hg (group R; p < 0.0001)., Conclusions: This novel aortic annuloplasty ring has the potential for supporting aortic valve reconstruction by remodeling the subvalvular area., (Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)
- Published
- 2014
- Full Text
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45. First clinical results with the new sinus prosthesis used for valve-sparing aortic root replacement.
- Author
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Schmidtke C, Sievers HH, Frydrychowicz A, Petersen M, Scharfschwerdt M, Karluss A, Stierle U, and Richardt D
- Subjects
- Adult, Aged, Aortic Valve diagnostic imaging, Aortic Valve physiology, Echocardiography, Female, Humans, Male, Middle Aged, Regional Blood Flow physiology, Replantation mortality, Sinus of Valsalva diagnostic imaging, Aortic Valve surgery, Blood Vessel Prosthesis Implantation methods, Cardiac Surgical Procedures methods, Replantation methods, Sinus of Valsalva surgery
- Abstract
Objectives: Sinuses of Valsalva are important in assuring the physiological function of the aortic valve. This study evaluates short-term clinical results of the reimplantation technique for aortic valve-sparing root replacement using a new prosthesis with three separate sinuses of Valsalva (sinus prosthesis)., Methods: Between February 2009 and February 2011, a total of 23 patients (20 m/3 f; mean age 52 ± 14.8 years; range 24-70 years) with aortic root aneurysm underwent aortic valve-sparing procedures according to the David reimplantation technique using the new sinus prosthesis. Eighteen patients had tricuspid and five patients bicuspid aortic valves. All patients received clinical as well as echocardiographic examinations postoperatively (mean 13 ± 9.3 months; 0.3-28 months)., Results: There was no death and no reoperation of the aortic valve. At latest follow-up, most patients were in New York Heart Association class I (n = 22; 95.7%). In 95.7% aortic valve regurgitation (AR) was 0 or 1+; one patient had AR 2+. Pressure gradients were between the normal range (mean pressure gradient 4.7 ± 1.9 mmHg). Echocardiographic images demonstrate physiological aortic root dimensions and configuration with three separate sinuses of Valsalva without systolic contact of leaflets to the wall., Conclusions: The new sinus prosthesis provides near normal root geometry and hemodynamics in valve-sparing aortic root replacement using the reimplantation technique, applicable for tricuspid and also bicuspid aortic valves.
- Published
- 2013
- Full Text
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46. Failed valve-in-valve transcatheter aortic valve implantation.
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Klotz S, Scharfschwerdt M, Richardt D, and Sievers HH
- Subjects
- Aged, Aortic Valve Stenosis diagnosis, Aortic Valve Stenosis physiopathology, Bioprosthesis, Device Removal, Heart Valve Prosthesis, Hemodynamics, Humans, Male, Prosthesis Failure, Treatment Failure, Aortic Valve Stenosis surgery, Cardiac Catheterization adverse effects, Cardiac Catheterization instrumentation, Heart Valve Prosthesis Implantation adverse effects, Heart Valve Prosthesis Implantation instrumentation
- Published
- 2012
- Full Text
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47. Comparison of outcomes in patients having isolated transcatheter aortic valve implantation versus combined with preprocedural percutaneous coronary intervention.
- Author
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Abdel-Wahab M, Mostafa AE, Geist V, Stöcker B, Gordian K, Merten C, Richardt D, Toelg R, and Richardt G
- Subjects
- Aged, 80 and over, Bioprosthesis, Feasibility Studies, Female, Heart Valve Prosthesis, Hemorrhage epidemiology, Humans, Kaplan-Meier Estimate, Male, Preoperative Care, Retrospective Studies, Stents, Stroke epidemiology, Angioplasty, Balloon, Coronary, Aortic Valve surgery, Coronary Artery Disease therapy, Heart Valve Prosthesis Implantation methods
- Abstract
Coronary artery disease negatively affects the outcome of patients undergoing surgical aortic valve replacement and practice guidelines recommend revascularization at time of surgery. In patients undergoing transcatheter aortic valve implantation (TAVI), the impact of preprocedural percutaneous coronary intervention (PCI) on TAVI outcome has not been examined. We aimed in the present study to assess the feasibility and safety of performing PCI before TAVI and to evaluate procedural, 30-day, and 6-month clinical outcomes. We retrospectively analyzed 125 patients who underwent successful TAVI at a single institution and divided them into an isolated TAVI and a PCI + TAVI group. During the study period, a strategy of preprocedural PCI of all significant (>50%) lesions in major epicardial vessels was adopted. Study end points were adjudicated in accordance with the Valve Academic Research Consortium consensus on event definition. All patients were treated with the Medtronic CoreValve prosthesis (n = 55 with PCI + TAVI and n = 70 with isolated TAVI). Thirty-day mortality was 2% versus 6% for patients treated with PCI + TAVI versus isolated TAVI, respectively (p = 0.27). Neither periprocedural nor spontaneous myocardial infarction occurred in either group. Rates of 30-day stroke, major bleeding, major vascular complications, and the Valve Academic Research Consortium-defined combined safety end point (11% vs 13%, p = 0.74) did not differ between the 2 groups. Patients' symptoms significantly improved in the first month after TAVI, and extent of improvement did not differ between groups. Adverse events at 6 months were comparable. In conclusion, PCI before TAVI appears feasible and safe. Based on these early results revascularization should become an important consideration in patients with coronary artery disease undergoing TAVI., (Copyright © 2012 Elsevier Inc. All rights reserved.)
- Published
- 2012
- Full Text
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48. Long-term results of 203 young and middle-aged patients with more than 10 years of follow-up after the original subcoronary Ross operation.
- Author
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Charitos EI, Stierle U, Hanke T, Schmidtke C, Sievers HH, and Richardt D
- Subjects
- Adult, Aortic Valve diagnostic imaging, Arrhythmias, Cardiac epidemiology, Endocarditis epidemiology, Endocarditis etiology, Endocarditis surgery, Female, Follow-Up Studies, Germany epidemiology, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Patient Selection, Postoperative Complications epidemiology, Prosthesis-Related Infections epidemiology, Prosthesis-Related Infections etiology, Prosthesis-Related Infections surgery, Reoperation statistics & numerical data, Thromboembolism epidemiology, Transplantation, Autologous, Transplantation, Heterotopic, Ultrasonography, Young Adult, Aortic Valve surgery, Bioprosthesis statistics & numerical data, Heart Valve Prosthesis statistics & numerical data, Pulmonary Valve transplantation
- Abstract
Background: The choice of prosthesis for aortic valve replacement in young and middle-aged patients remains challenging owing to the accelerated degeneration of bioprostheses in these age groups and the risks of thromboembolism and bleeding with mechanical valves. Theoretically, the living pulmonary autograft (Ross operation) would be advantageous. Long-term results of the various Ross techniques are needed for defining the value of this surgical concept., Methods: Of a total of 576 subcoronary Ross patients operated on between June 1994 and June 2011, we report on 203 consecutive subcoronary patients (mean age, 47.2±13.6 years, 155 male, 2,491 patient-years) with a follow-up of at least 10 years (mean, 12.3±2.9 years)., Results: Early and late mortality were 0.98% (n=2) and 11.4% (n=23). Valve-related mortality was 2.5% (n=5). Survival did not differ from that of the general German population. Freedom from autograft or allograft reoperation was 92.2% at 10 years and 87.1% at 15 years. Five major bleeding (0.20%/patient-year) and 11 thromboembolic events (0.44%/patient-year) occurred in 5 and 10 patients, respectively. Neither a systematic increase in aortic regurgitation nor an increase in root dimensions with time could be observed. In the vast majority of patients, valvular hemodynamics at latest echocardiographic follow-up were excellent., Conclusions: Long-term results of the original subcoronary Ross operation reveal normal survival, excellent hemodynamics, low risk of thromboembolism or bleeding, and small risk for reoperation. These results favor the pulmonary autograft concept in young and middle-aged patients in experienced centers and may serve to better define its role in surgical treatment of aortic valve disease in these patients., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)
- Published
- 2012
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49. Organotypic slice culture from human adult ventricular myocardium.
- Author
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Brandenburger M, Wenzel J, Bogdan R, Richardt D, Nguemo F, Reppel M, Hescheler J, Terlau H, and Dendorfer A
- Subjects
- Adult, Cardiovascular Physiological Phenomena, Electrophysiological Phenomena, Heart Ventricles surgery, Humans, Myocardial Contraction, Heart Ventricles anatomy & histology, Models, Cardiovascular, Myocardium metabolism, Organ Culture Techniques methods
- Abstract
Aims: Cardiovascular research requires complex and functionally intact experimental models. Due to major differences in the cellular and subcellular composition of the myocardium between species, the use of human heart tissue is highly desirable. To enhance the experimental use of the human myocardium, we established methods for the preparation of vital tissue slices from the adult ventricular myocardium as well as conditions for their long-term preservation in organotypic culture., Methods and Results: Human ventricular heart samples were derived from surgical specimens excised during a therapeutic Morrow myectomy and cut into 300 μm thick slices. Slices were either characterized in acute experiments or cultured at a liquid-air interface. Viability and functionality were proven by viability staining, enzyme activity tests, intracellular potential recordings, and force measurements. Precision-cut slices showed high viability throughout 28 days in culture and displayed typical cardiomyocyte action potential characteristics, which enabled pharmacological safety testing on the rapid component of the delayed rectifier potassium current (I(Kr)) and ATP-dependent potassium channels throughout the whole culture period. Constant expression of major ion channels was confirmed by quantitative PCR. Acute slices developed excitation-dependent contractions with a clear preload dependency and a β-adrenergic response. Contractility and myosin light chain expression decreased during the first days in culture but reached a steady state with reactivity upon β-adrenergic stimulation being preserved., Conclusion: Organotypic heart slices represent a multicellular model of the human myocardium and a novel platform for studies ranging from the investigation of molecular interactions to tissue engineering.
- Published
- 2012
- Full Text
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50. Upregulation of the high mobility group AT-hook 2 gene in acute aortic dissection is potentially associated with endothelial-mesenchymal transition.
- Author
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Belge G, Radtke A, Meyer A, Stegen I, Richardt D, Nimzyk R, Nigam V, Dendorfer A, Sievers HH, Tiemann M, Buchwalow I, Bullerdiek J, and Mohamed SA
- Subjects
- Adult, Aortic Dissection genetics, Aortic Dissection metabolism, Aortic Aneurysm genetics, Aortic Aneurysm metabolism, Endothelium, Vascular metabolism, Female, HMGA2 Protein metabolism, Humans, Male, Middle Aged, Snail Family Transcription Factors, Transcription Factors metabolism, Up-Regulation, Vasa Vasorum metabolism, Vasa Vasorum pathology, Vimentin metabolism, Aortic Dissection pathology, Aortic Aneurysm pathology, Endothelium, Vascular pathology, Epithelial-Mesenchymal Transition physiology, Gene Expression Regulation, HMGA2 Protein genetics
- Abstract
The high mobility group AT-hook 2 (HMGA2) gene is proposed to regulate the genes involved in the epithelial-mesenchymal transition (EMT). One form of EMT is endothelial-mesenchymal transition (EndMT). We analyzed the expression profile of the HMGA2 gene in different human aortic diseases. Aortic specimens were collected from 51 patients, including 19 with acute aortic dissection, 26 with aortic aneurysm, two with Marfan syndrome and four aortic valves. Quantitative real-time polymerase chain reaction was carried out for HMGA2 and immunohistochemical analyses were performed for HMGA2, SNAI1, Vimentin, CD34, MKI-67 and TGFB1. The expression of let-7d microRNA, which is assumed to play a role in the regulation of HMGA2, was also quantified. The level of HMGA2 gene expression was significantly higher in acute aortic dissection compared with all the other samples (193.1 vs. 8.1 fold normalized to calibrator, P<0.001). The immunohistochemical investigation showed that HMGA2, SNAI1, and Vimentin proteins were mainly detected in the endothelial cells of the vasa vasorum. The HMGA2 gene is upregulated in acute aortic dissection. This is the first report describing a link between HMGA2 and acute aortic dissection. The HMGA2, SNAI1 and Vimentin proteins were mainly detected in the endothelium of the vasa vasorum. It seems that HMGA2 overexpression in acute aortic dissection occurs in a let-7d-independent manner and is associated with EndMT of the vasa vasorum.
- Published
- 2011
- Full Text
- View/download PDF
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