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Background/Introduction Long-term continuous flow left ventricular assist device (cf-LVAD) can result in the development of relevant aortic regurgitation (AR). Although its impact on survival is still controversial, it causes heart failure related symptoms. Current evidence for less invasive strategies to treat AR in cf-LVAD patients is limited. Purpose This study sought to investigate the value of transcatheter aortic valve implantation (TAVI) to treat severe de novo AR in patients on long-term cf-LVAD support. Methods We performed a retrospective analysis of 13 patients with severe AR following cf-LVAD implantation treated with TAVI between 2010 and 2019. TAVI's were performed via transfemoral (n=11), transapical (n=1) and transaxillary (n=1) access route. CoreValve (n=2), LotusValve (n=1), SapienXT (n=1) and Sapien3 (n=9) were used as transcatheter heart valves. In 4 patients, a new off-label strategy using landing-zone pre-stenting with a Sinus-XL stent was used (Figure 1). Results The median time interval from LVAD-implantation to TAVI was 1.7 years [interquartile range (IQR): 1.0 - 3.1]. Median age was 62 years [IQR: 57 - 67]. No procedural mortality or stroke was observed. Overall, device success according to VARC-II criteria was low due to a high rate of second valve necessity (54%). In contrast to the standard implantation technique, device success was 100% when the newly developed pre-stenting technique was applied (Table 1). Aortic regurgitation at discharge was none/trace in all patients. Valve function remained stable in all patients during a median echocardiographic follow-up time of 105 days [IQR: 11 - 298]. Table 1 Overall Sinus-XL prestenting (n=4) NO prestenting (n=9) Device success 7 (54) 4 (100) 3 (33) Procedural mortality 0 (0) 0 (0) 0 (0) Correct positioning of a single valve 7 (54) 4 (100) 3 (33) Intended valve performance 13 (100) 4 (100) 9 (100) Moderate or severe aortic regurgitation 0 (0) 0 (0) 0 (0) Figure 1 Conclusions Transcatheter aortic valve implantation is an efficient tool to treat cf-LVAD induced severe AR. The challenging anatomy of the non-calcified device landing zone causes a relatively high rate of primary device failure, which could be overcome with a pre-stenting technique. Acknowledgement/Funding None

OBJECTIVE: Transapical aortic valve implantation (TAVI) is a new method that might reduce the surgical risk of conventional surgical aortic valve replacement in very high-risk patients. Increased downstream microembolization is expected in transapical aortic valve implantation. However, whether it usually occurs, how often, and its clinical relevance are not known. We report the results of ultrasound microembolic signal detection in the middle cerebral artery during the procedure. METHODS: Fifty patients (mean age: 80 ± 5 years; mean EuroSCORE: 36 ± 13 %) underwent transapical aortic valve implantation. Intraoperative transcranial Doppler (TCD) sound examination of both middle cerebral arteries (MCA) was used to identify high-intensity transient signals (HITS) and microembolic signals (MES) during seven phases of the procedure. Pre- and postoperative computed tomography of the brain and clinical neurological examinations were performed preoperatively and daily during the first postoperative week. RESULTS: During the procedure, HITS [right MCA: 435 ± 922 (range 9-5765); left MCA: 471 ± 996 (range 24-6432)] and MES [right MCA: 78 ± 172 (range 1-955); left MCA: 62 ± 190 (range 2-1553)] were detected in all patients. Most of the MES were recorded during valvuloplasty [right MCA: 3 ± 5.6 (range 0-31); left MCA: 2 ± 4.9 (range 0-30)] and positioning of the prosthetic valve in the aortic position [right MCA: 6 ± 5 (range 0-22); left MCA: 2 ± 6.9 (range 0-38)]. Postoperatively, there were no clinical signs of new cerebral embolism. CONCLUSIONS: Cerebral microemboli were detected by intraoperative transcranial Doppler sound examinations in all patients during transapical aortic valve implantation. Most of the signals were detected during balloon valvuloplasty and delivery of the prosthetic valve.

Endograftimplantationen im oder am Aortenbogen stellen besondere Herausforderungen an die Implantationstechnik und an die mechanischen Eigenschaften von Stentgrafts und ihren Einfuhrungssystemen, bedingt durch die Notwendigkeit, die Prothesen punktgenau abzusetzen und durch die mit der Biegung im Aortenbogen zunehmende Reibungswiderstande innerhalb der Einfuhrungssysteme. Die Endograftsysteme der 1. Generation (Talent®, Zenith TX 1®, TAG®) zeigten in dieser Lokalisation technisch bedingte Limitationen. Bei den seit 2004 und 2005 verfugbaren neuen Stentgrafts (E-vita®, Zenith TX 2®, Valiant®, Relay®) sind diese Limitationen weitgehend uberwunden. Durch technische Verbesserungen von Stentgrafts und Einfuhrungssystemen ist es nun moglich, auch lange Segmente bis zu 230 mm prazise im Aortenbogen freizusetzen. Durch Verzicht auf einen Langsdraht (E-vita®, Zenith TX 2®, Valiant®) bzw. Modifikation des Langsdrahtes (Relay®) sind diese neuen Prothesen flexibler als die von uns zuvor vornehmlich verwendete Talent®. Die neuen Prothesen unterscheiden sich in wesentlichen technischen Details, vor allem hinsichtlich der verwendeten Metallkomponenten (Nitinol vs. Edelstahl) und der proximalen Fixierungsmechanismen (freie Federn vs. Haken oder glattem Abschluss). Diese Unterschiede sind bei differenzierter Indikationsstellung zu berucksichtigen. Wir haben im Aortenbogen bis 2004 fast ausschlieslich Talent® (73 Patienten) und seitdem E-vita® (37 Patienten) implantiert. Die Erfahrungen mit der E-vita® sind sehr positiv. Dieses Implantat erschliest komplexe Aortenerkrankungen mit Beteiligung des Bogens der endovaskularen Therapie. Mit Sonderanfertigungen, die innerhalb kurzer Zeit produziert und geliefert werden, ist auch die Versorgung schwieriger anatomischer Verhaltnisse moglich. Die Erfahrungen mit den anderen neuen Systemen beschranken sich noch auf Einzelfalle. Mit einem neu entwickelten Hybrid-Endograft aus endovaskularer und konventioneller Aortenprothese (E-vita open®) konnen komplexe Aortenerkrankungen mit Beteiligung der Aorta ascendens, des Aortenbogens und der Aorta descendens einzeitig im Kreislaufstillstand und tiefer Hypothermie operiert werden. Endoprothesen mit Seitenarmen oder Fenestrationen konnten das Spektrum der endovaskularen Behandlung weiter bereichern. Entwicklungsarbeiten hierzu sind im Gange.

Objective Bivalirudin has been successfully used as a replacement for heparin during on-pump coronary artery bypass grafting. This study was conducted to assess the effects of the currently suggested protocol for bivalirudin on hemostatic activation during cardiopulmonary bypass with and without cardiotomy suction. Methods Ten patients scheduled for coronary artery bypass grafting were enrolled. Bivalirudin was given with a bolus of 50 mg in the priming solution and 1.0 mg/kg for the patient, followed by an infusion of 2.5 mg · kg −1 · h −1 until 15 minutes before the conclusion of cardiopulmonary bypass. Cardiopulmonary bypass was performed with a closed system in 5 patients with and in 5 patients without the use of cardiotomy suction. Blood samples were obtained before and after cardiopulmonary bypass. D-dimers, fibrinopeptide A, prothrombin 1 and 2 fragments, thrombin-antithrombin, and factor XIIa were determined. Results Values for factor XIIa remained almost unchanged in both groups, indicating a minor effect of contact activation. In patients without cardiotomy suction, post-cardiopulmonary bypass values for D-dimers, fibrinopeptide A, prothrombin 1 and 2 fragments, and thrombin-antithrombin were not significantly increased compared with pre-cardiopulmonary bypass values. In patients with cardiotomy suction, values obtained for these parameters had significantly increased compared with pre-cardiopulmonary bypass values and the values obtained in the group without cardiotomy suction after cardiopulmonary bypass. Conclusions With this protocol, hemostatic activation during cardiopulmonary bypass was almost completely attenuated when cardiotomy suction was avoided. Cardiotomy suction results in considerable activation of the coagulation system and should therefore be restricted and replaced by cell saving whenever possible.

Objective: The increasing number of transcatheter aortic valve implantations (TAVI) has led to an increasing number of techniques for optimal aortic annulus sizing. Three dimensional transesophageal echocardiography (3TEE) and specialized TAVI software (e.g., 3mensio) for 3-dimensional reconstructive computed tomography (3RCT) have become standard in several institutions. In this study the accuracy of the two techniques was compared. Methods: Between 04/2008 and 09/2014, 1032 consecutive patients underwent TAVI. Since 09/2012 3TEE and since 04/2014 3RCT have been in clinical practice. In 37 (24 women) patients both aortic annulus sizing tools were used to allow a comparison. Seventeen patients underwent transapical, 16 patients transfemoral, and 4 patients transaortic valve implantation. Twenty-one Edwards Sapien valves, 6 CoreValves, 5 Portico,3 DirectFlow and 2 JenaValves were implanted. The EuroScore I was 32% (range: 5–97), EuroScore II: 16% (range: 1–89), and STS PROM Score: 9.9% (range: 2–64). Results: Technical success rate was 100%. Whereas in 3TEE the mean annulus area was 454 mm2 (range: 270–930) with an area derived diameter of 23.8 mm (range: 19–34) and the mean perimeter 77 mm (range 61–115) with a perimeter derived diameter of 24.6 mm (range: 19–36.6), in 3RCT the mean area was 427 mm2 (range: 319–616) with an area derived diameter of 23 mm (range: 20.4–29) and the mean perimeter 80.8 mm (range 21.5–98) with an perimeter derived diameter of 23.6 mm (range: 20.5–28.5). The mean difference between 3TEE and 3RCT derived diameter was 0.54 mm and the mean difference between 3TEE and 3RCT derived perimeter was 0.55 mm. Conclusions: The introduction of both tools allows perfect sizing of the virtual aortic annulus. 3RCT is a precise tool for optimal sizing with no examiner dependent variations. On the other hand, especially in patients with contraindication for computed tomography (e.g., urgent cases, kidney failure), 3TEE is a precise alternative.

Das Hamangioperizytom als primar kardialer Tumor ist nur selten zu finden. Im Folgenden berichten wir uber eine 63-jahrige Patientin, bei der ein primar kardiales Hamangioperizytom Ausgangspunkt fur eine pulmonale Metastasierung war.¶ Nach Resektion von pulmonalen Metastasen war die Suche nach einem Primartumor zunachst erfolglos geblieben. Zwei Jahre spater stellte sich die Patientin mit einer schweren Belastungsinsuffizienz bei subtotaler Obstruktion des rechten Ventrikelcavums durch ein primar kardiales Hamangioperizytom erneut vor. Durch eine makroskopisch vollstandige Resektion des Tumors konnte eine gute Belastungsfahigkeit erzielt werden. 1 Jahr nach dem Eingriff war die Patientin beschwerdefrei.¶ In der vorliegenden Arbeit wird eine Zusammenstellung der bisher veroffentlichten Falle geliefert. In 7 von 8 Fallen ging das Hamangioperizytom als primar kardialer Tumor vom rechten Herzen aus.

Jahrlich werden in Deutschland ca. 75000 Patienten mit koronarer Herzerkrankung (ca. 75% aller Herzoperationen) operativ versorgt. Als Bypassmaterial stehen arterielle Grafts und autologe Venen, vorwiegend die Vena saphena magna, zur Verfugung. In den letzten Jahren revolutionieren minimal-invasive Venenentnahmetechniken die Bypasschirurgie, dennoch erfolgt heute die Saphenektomie zum Grosteil mittels kontinuierlicher Inzision der Haut vom Knochel bis in die Leiste zur offenen Praparation der Vena saphena magna. Wundheilungsstorungen nach offener Saphenektomie werden wiederholt diskutiert und sind Gegenstand jeder herzchirurgischen Nachbehandlung nach koronarchirurgischen Eingriffen und Grund fur die Aufwertung neuer, minimal-invasiver Entnahmetechniken. Diese Wundheilungsstorungen, je nach Beobachtungszeitraum, werden in der Literatur zwischen 5–25% angegeben. Die Vor- und Nachteile minimal-invasiver Systeme sind derzeit Inhalt kontroverser Diskussion.¶ Die vorgestellte Technik (modifizierte „Bridge”-Technik) zeigt erwunschte Ergebnisse, insbesondere eine sehr hohe Patientenzufriedenheit hinsichtlich des kosmetischen Ergebnisses und der nur geringen Einschrankung durch die Saphenektomiewunde(n). Es lies sich nur eine geringe Rate an postoperativen Komplikationen (hier 3%) feststellen. Minimal-invasive Venenentnahmesysteme halten wir fur praktikabel, effizient und leicht erlernbar. Wir sehen es deshalb als wichtig an, diese Techniken weiter im klinischen Gebrauch zu etablieren.

This paper presents an extension of instrumental variable estimation to nonlinear regression models. For the linear model, the extended estimator is equivalent to the two-stage least squares estimator. The extended estimator is consistent for an important class of nonlinear models, including the logistic model, under relatively weak assumptions on the distribution of the measurement error. An example and simulation study are presented for the logistic regression model. The simulations suggest the estimator is reasonably efficient.

Methods Between 01/1996 and 09/2011, 836 patients (559 men) with a mean age of 59.6±13.6 (range 18-92) years underwent surgery for acute type-A aortic dissection. No patients were excluded from immediate operation irrespective of age and preoperative status unless uncontrollable hemorrhage and/or cardiac arrest occurred before the patient reached the operating room. Ninety-two perioperative variables were statistically analyzed to identify predictors for early mortality.

Inhaled nitric oxide (iNO) therapy is an effective treatment of pulmonary hypertension following left ventricular assist device (LVAD) implantation. As iNO may also modulate circulating endothelin-1 (ET-1) and big endothelin following LVAD implantation, we investigated the effects of iNO on ET-1 and big endothelin plasma concentration gradients. In order to assist weaning from cardiopulmonary bypass, iNO was administered to 15 consecutive patients with secondary pulmonary hypertension following implantation of a LVAD. Central venous, pulmonary arterial and arterial ET-1 and big endothelin plasma levels were measured preoperatively, on cardiopulmonary bypass prior to iNO administration, 12, 24 and 48 hours postoperatively, and 72 hours after weaning from iNO. The ET-1 gradients between central venous and pulmonary arterial plasma levels decreased significantly with time, and there was a trend for lower arterial-pulmonary arterial plasma concentration gradients. Big endothelin plasma concentration gradients were not altered significantly. The decrease in ET-1 plasma concentration gradients during and after iNO administration may reflect a restoration of the physiologic balance between the different vascular beds. This provides further evidence that intermittent iNO therapy may modulate ET-1 after LVAD implantation.