78 results on '"Sündermann Simon"'
Search Results
2. The role of concomitant coronary artery bypass grafting in acute type A aortic dissection complicated by coronary malperfusion.
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Pitts, Leonard, Kofler, Markus, Montagner, Matteo, Heck, Roland, Kurz, Stephan Dominik, Sündermann, Simon, Falk, Volkmar, and Kempfert, Jörg
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CORONARY artery bypass ,ARTERIAL dissections ,AORTIC dissection ,CARDIAC output ,TREATMENT effectiveness - Abstract
OBJECTIVES Managing acute type A aortic dissection with coronary malperfusion is challenging. This study outlines our revascularization strategy for these patients. METHODS Patients undergoing surgery for acute type A aortic dissection with coronary malperfusion and aortic root involvement from January 2000 to December 2021 were included. Patients were classified using the Neri classification for coronary dissection, including a novel 'Neri −' class (no coronary dissection). Patients undergoing revascularization either as a planned or as a bailout strategy due to persisting low cardiac output were compared additionally. RESULTS The cohort comprised 195 patients: 43 (22%) Neri −, 43 (22%) Neri A, 74 (38%) Neri B and 35 (18%) Neri C. Aortic root replacement was mainly performed in 25 Neri C patients (71%; P < 0.001). Concomitant bypass surgery was performed in 4 (9%) of Neri −, 5 (12%) of Neri A, 21 (28%) of Neri B and 32 (91%) of Neri C patients (P < 0.001). Thirty-day mortality was 42% with 21 (49%) Neri −, 12 (28%) Neri A, 30 (41%) Neri B and 19 (54%) Neri C patients (P = 0.087). Bailout revascularization was primarily performed in 11 Neri B patients (69%; P = 0.001) and associated with a higher 30-day mortality of 81% compared to 48% for planned revascularization (P = 0.042). CONCLUSIONS Postoperative outcomes in case of coronary malperfusion are poor, irrespective of the anatomic dissection pattern. The decision for concomitant bypass surgery is crucial but may be considered in Neri C patients combined with aortic root replacement. Bailout revascularization was most common in Neri B and showed dismal outcome. [ABSTRACT FROM AUTHOR]
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- 2024
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3. The Ascyrus Medical Dissection Stent: A One-Fits-All Strategy for the Treatment of Acute Type A Aortic Dissection?
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Pitts, Leonard, Moon, Michael C., Luehr, Maximilian, Kofler, Markus, Montagner, Matteo, Sündermann, Simon, Buz, Semih, Starck, Christoph, Falk, Volkmar, and Kempfert, Jörg
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AORTIC dissection ,THORACIC aorta ,ENDOVASCULAR aneurysm repair ,DISSECTION - Abstract
The treatment of DeBakey type I aortic dissection remains a major challenge in the field of aortic surgery. To upgrade the standard of care hemiarch replacement, a novel device called an "Ascyrus Medical Dissection Stent" (AMDS) is now available. This hybrid device composed of a proximal polytetrafluoroethylene cuff and a distal non-covered nitinol stent is inserted into the aortic arch and the descending thoracic aorta during hypothermic circulatory arrest in addition to hemiarch replacement. Due to its specific design, it may result in a reduced risk for distal anastomotic new entries, the effective restoration of branch vessel malperfusion and positive aortic remodeling. In this narrative review, we provide an overview about the indications and the technical use of the AMDS. Additionally, we summarize the current available literature and discuss potential pitfalls in the application of the AMDS regarding device failure and aortic re-intervention. [ABSTRACT FROM AUTHOR]
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- 2024
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4. A simulation-based phantom model for generating synthetic mitral valve image data–application to MRI acquisition planning.
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Manini, Chiara, Nemchyna, Olena, Akansel, Serdar, Walczak, Lars, Tautz, Lennart, Kolbitsch, Christoph, Falk, Volkmar, Sündermann, Simon, Kühne, Titus, Schulz-Menger, Jeanette, and Hennemuth, Anja
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Purpose: Numerical phantom methods are widely used in the development of medical imaging methods. They enable quantitative evaluation and direct comparison with controlled and known ground truth information. Cardiac magnetic resonance has the potential for a comprehensive evaluation of the mitral valve (MV). The goal of this work is the development of a numerical simulation framework that supports the investigation of MRI imaging strategies for the mitral valve. Methods: We present a pipeline for synthetic image generation based on the combination of individual anatomical 3D models with a position-based dynamics simulation of the mitral valve closure. The corresponding images are generated using modality-specific intensity models and spatiotemporal sampling concepts. We test the applicability in the context of MRI imaging strategies for the assessment of the mitral valve. Synthetic images are generated with different strategies regarding image orientation (SAX and rLAX) and spatial sampling density. Results: The suitability of the imaging strategy is evaluated by comparing MV segmentations against ground truth annotations. The generated synthetic images were compared to ones acquired with similar parameters, and the result is promising. The quantitative analysis of annotation results suggests that the rLAX sampling strategy is preferable for MV assessment, reaching accuracy values that are comparable to or even outperform literature values. Conclusion: The proposed approach provides a valuable tool for the evaluation and optimization of cardiac valve image acquisition. Its application to the use case identifies the radial image sampling strategy as the most suitable for MV assessment through MRI. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Preinterventional frailty assessment in patients scheduled for cardiac surgery or transcatheter aortic valve implantation: a consensus statement of the European Association for Cardio-Thoracic Surgery (EACTS) and the European Association of Preventive Cardiology (EAPC) of the European Society of Cardiology (ESC)
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Niebauer, Josef, Bäck, Caroline, Bischoff-Ferrari, Heike A, Dehbi, Hakim-Moulay, Szekely, Andrea, Völler, Heinz, and Sündermann, Simon H
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- 2024
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6. Preinterventional frailty assessment in patients scheduled for cardiac surgery or transcatheter aortic valve implantation: a consensus statement of the European Association for Cardio-Thoracic Surgery (EACTS) and the European Association of Preventive Cardiology (EAPC) of the European Society of Cardiology (ESC)
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Sündermann, Simon H, Bäck, Caroline, Bischoff-Ferrari, Heike A, Dehbi, Hakim-Moulay, Szekely, Andrea, Völler, Heinz, and Niebauer, Josef
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HEART valve prosthesis implantation ,GERIATRIC assessment ,AORTIC valve surgery ,HEART failure ,CARDIAC surgery ,MITRAL valve insufficiency ,FRAILTY ,QUALITY of life ,CORONARY artery bypass - Abstract
Google Scholar Crossref Search ADS PubMed WorldCat 37 Saji M, Lim DS, Ragosta M, LaPar DJ, Downs E, Ghanta RK et al Usefulness of Psoas Muscle Area to Predict Mortality in Patients Undergoing Transcatheter Aortic Valve Replacement. Based on that, they built 3 groups of patients with different stages of frailty and found that frail patients had significantly lower SF-36 scores for general health, social functioning and role emotional after the procedure and that severely frail patients had worse postoperative SF-36 scores than moderately and not-frail patients. 3.4 Summary of consensus statements on frailty assessment in transcatheter aortic valve impla... 3.4.1 Consensus statements: prediction of mortality after transcatheter aortic valve implantation HT
Consensus statements: prediction of mortality after transcatheter aortic valve implantation. Preventive Cardiology (EAPC) of the European Society of Cardiology (ESC). [Extracted from the article] - Published
- 2023
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7. Image-based ring size prediction for mitral valve repair.
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Akansel, Serdar, Kofler, Markus, Praet, Karel M Van, Sündermann, Simon H, Kukucka, Marian, Jacobs, Stephan, Falk, Volkmar, and Kempfert, Jörg
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MITRAL valve ,MITRAL valve insufficiency ,REGRESSION analysis ,FORECASTING ,STATISTICAL correlation - Abstract
Open in new tab Download slide OBJECTIVES Annuloplasty rings are routinely used in mitral valve repair (MVr). However, accurate annuloplasty ring size selection is essential to obtain a favourable outcome. Moreover, ring sizing can be challenging in some patients and is highly influenced by surgeons' experience. This study investigated the utility of three-dimensional mitral valve (3D-MV) reconstruction models to predict annuloplasty ring size for MVr. METHODS A total of 150 patients undergoing minimally invasive MVr with annuloplasty ring due to Carpentier type II pathology and who were discharged with none/trace residual mitral regurgitation were included. 3D-MV reconstruction models were created with a semi-automated software package (4D MV Analysis) to quantitate mitral valve geometry. To predict the ring size, univariable and multivariable linear regression analyses were performed. RESULTS Between 3D-MV reconstruction values and implanted ring sizes, the highest correlation coefficients were provided by commissural width (CW) (0.839; P < 0.001), intertrigonal distance (ITD) (0.796; P < 0.001), annulus area (0.782; P < 0.001), anterior mitral leaflet area (0.767; P < 0.001), anterior–posterior diameter (0.679; P < 0.001) and anterior mitral leaflet length (0.515; P < 0.001). In multivariable regression analysis, only CW and ITD were found to be independent predictors of annuloplasty ring size (R
2 = 0.743; P < 0.001). The highest level of agreement was achieved with CW and ITD, and 76.6% of patients received a ring with no >1 ring size difference from the predicted ring sizes. CONCLUSIONS 3D-MV reconstruction models can support surgeons in the decision-making process for annuloplasty ring sizing. The present study may be a first step towards accurate annuloplasty ring size prediction using multimodal machine learning decision support. [ABSTRACT FROM AUTHOR]- Published
- 2023
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8. The 10 Commandments for Transaxillary TAVI.
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Sündermann, Simon H., Dreger, Henryk, Hinkov, Hristian, and Kempfert, Jörg
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- 2023
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9. Minimally Invasive Extirpation of Benign Atrial Cardiac Tumors: Clinical Follow-Up and Survival.
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Van Praet, Karel M., Kofler, Markus, Wilkens, Kristin, Sündermann, Simon H., Meyer, Alexander, Hommel, Matthias, Jacobs, Stephan, Falk, Volkmar, and Kempfert, Jörg
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- 2023
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10. Comparison of hemodynamics in biological surgical aortic valve replacement and transcatheter aortic valve implantation: An in‐silico study.
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Franke, Benedikt, Schlief, Adriano, Walczak, Lars, Sündermann, Simon, Unbehaun, Axel, Kempfert, Jörg, Solowjowa, Natalia, Kühne, Titus, and Goubergrits, Leonid
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HEART valve prosthesis implantation ,AORTIC valve ,AORTIC valve transplantation ,HEMODYNAMICS ,DIALYSIS catheters ,FLOW simulations - Abstract
Objectives: In aortic valve replacement (AVR), the treatment strategy as well as the model and size of the implanted prosthesis have a major impact on the postoperative hemodynamics and thus on the clinical outcome. Preinterventional prediction of the hemodynamics could support the treatment decision. Therefore, we performed paired virtual treatment with transcatheter AVR (TAVI) and biological surgical AVR (SAVR) and compared hemodynamic outcomes using numerical simulations. Methods: 10 patients with severe aortic stenosis (AS) undergoing TAVI were virtually treated with both biological SAVR and TAVI to compare post‐interventional hemodynamics using numerical simulations of peak‐systolic flow. Virtual treatment procedure was done using an in‐house developed tool based on position‐based dynamics methodology, which was applied to the patient's anatomy including LVOT, aortic root and aorta. Geometries were automatically segmented from dynamic CT‐scans and patient‐specific flow rates were calculated by volumetric analysis of the left ventricle. Hemodynamics were assessed using the STAR CCM+ software by solving the RANS equations. Results: Virtual treatment with TAVI resulted in realistic hemodynamics comparable to echocardiographic measurements (median difference in transvalvular pressure gradient [TPG]: −0.33 mm Hg). Virtual TAVI and SAVR showed similar hemodynamic functions with a mean TPG with standard deviation of 8.45 ± 4.60 mm Hg in TAVI and 6.66 ± 3.79 mm Hg in SAVR (p = 0.03) while max. Wall shear stress being 12.6 ± 4.59 vs. 10.2 ± 4.42 Pa (p = 0.001). Conclusions: Using the presented method for virtual treatment of AS, we were able to reliably predict post‐interventional hemodynamics. TAVI and SAVR show similar hemodynamics in a pairwise comparison. [ABSTRACT FROM AUTHOR]
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- 2023
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11. Right Antero-Lateral Mini-Thoracotomy Surgical Aortic Valve Replacement.
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VAN PRAET, KAREL M., NERSESIAN, GAIK, SÜNDERMANN, SIMON H., UNBEHAUN, AXEL, FALK, VOLKMAR, and KEMPFERT, JÖRG
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- 2022
12. Single-Center Experience With a Self-Expandable Venous Cannula During Minimally Invasive Cardiac Surgery.
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Van Praet, Karel M., Kofler, Markus, Meyer, Alexander, Sündermann, Simon H., Hommel, Matthias, Falk, Volkmar, and Kempfert, Jörg
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- 2022
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13. Factors associated with an unsuccessful fast-track course following minimally invasive surgical mitral valve repair.
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Praet, Karel M Van, Kofler, Markus, Hirsch, Solveig, Akansel, Serdar, Hommel, Matthias, Sündermann, Simon H, Meyer, Alexander, Jacobs, Stephan, Falk, Volkmar, and Kempfert, Jörg
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MITRAL valve ,MITRAL valve surgery ,LOGISTIC regression analysis ,CORONARY artery disease ,INTENSIVE care units ,ARTIFICIAL respiration ,EXTUBATION - Abstract
Open in new tab Download slide OBJECTIVES Analyses of fast-track (FT) processes demonstrated that low-risk cardiac surgical patients require minimal intensive care, with a low incidence of mortality or morbidity. We investigated perioperative factors and their association with fast-track failure (FTF) in a retrospective cohort study of patients undergoing minimally invasive mitral valve surgery. METHODS Patients undergoing minimally invasive surgical mitral valve repair for Carpentier type I or type II mitral regurgitation between 2014 and 2020 were included in the study. The definition of FTF consisted of >10 h mechanical ventilation, >24 h intensive care unit stay, reintubation after extubation and re-admission to the intensive care unit. Multivariable logistic regression analysis enabled the identification of factors associated with FTF. RESULTS In total, 491 patients were included in the study and were analysed. Two hundred and thirty-seven patients (48.3%) failed the FT protocol. Multivariable logistic regression analysis showed that a New York Heart Association classification ≥III [odds ratio (OR) 2.05; 95% confidence interval (CI) 1.38–3.08; P < 0.001], pre-existing chronic kidney disease (OR 2.03; 95% CI 1.14–3.70; P = 0.018), coronary artery disease (OR 1.90; 95% CI 1.13–3.23; P = 0.016), postoperative bleeding requiring surgical revision (OR 8.36; 95% CI 2.81–36.01; P < 0.001) and procedure time (OR 1.01; 95% CI 1.01–1.01; P < 0.001) were independently associated with FTF. CONCLUSIONS Factors associated with FTF in patients with Carpentier type I and II pathologies undergoing minimally invasive mitral valve repair are a New York Heart Association classification III–IV at baseline, pre-existing chronic kidney disease and coronary artery disease. Postoperative bleeding requiring rethoracotomy and procedure time were also identified as important factors associated with failed FT. [ABSTRACT FROM AUTHOR]
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- 2022
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14. arch remodelling stent for DeBakey I acute aortic dissection: experience with 100 implantations.
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Montagner, Matteo, Kofler, Markus, Seeber, Fabian, Pitts, Leonard, Starck, Christoph, Sündermann, Simon H, Kurz, Stephan, Grubitzsch, Herko, Falk, Volkmar, and Kempfert, Jörg
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AORTIC dissection ,AXILLARY artery ,THORACIC aorta ,VASCULAR remodeling ,COMPUTED tomography ,DISSECTION - Abstract
Open in new tab Download slide OBJECTIVES A novel hybrid non-covered stent was developed to treat malperfusion and prevent aneurysm formation following hemiarch procedure for DeBakey I acute aortic dissection (AAD). The present analysis investigates the performance of the device in 100 consecutive implantations. METHODS Between 2018 and 2021, 100 patients underwent surgical repair of DeBakey I AAD with implantation of a non-covered stent in the arch and descending aorta. The primary entry tear was located in the root or the ascending aorta. Clinical and imaging data were collected and analysed retrospectively. The endpoints of the study were 30-day mortality, neurological outcome and need of additional procedures due to postoperative malperfusion. Technical success was assessed in the first postoperative computed tomography in regard to the induction of false lumen thrombosis in the descending aorta. RESULTS The median age was 61 (54–73) years. Preoperative malperfusion was present in 46 (46%) patients. The primary arterial cannulation strategy was the right axillary artery and an open distal anastomosis was performed in a median caudal circulatory arrest of 40 (34–52) min. In 48% of cases, a 55–40 tapered stent was implanted. The 30-day mortality was 18%, and the operation-related new postoperative neurological deficit was present in 8%. Technical success was achieved in 76% of patients. CONCLUSIONS The novel non-covered stent can be safely applied to complement aortic repair with the hemiarch procedure for DeBakey I AAD. The expansion of the true lumen through the device may prevent postoperative malperfusion and induces positive vascular remodelling with the thrombosis of the false lumen. [ABSTRACT FROM AUTHOR]
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- 2022
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15. Periareolar endoscopic minimally invasive cardiac surgery: postoperative scar assessment analysis.
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Praet, Karel M Van, Kofler, Markus, Akansel, Serdar, Montagner, Matteo, Meyer, Alexander, Sündermann, Simon H, Falk, Volkmar, and Kempfert, Jörg
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- 2022
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16. Minimally invasive mitral valve surgery after failed transcatheter mitral valve repair in an intermediate-risk cohort.
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Akansel, Serdar, Kofler, Markus, Praet, Karel M Van, Unbehaun, Axel, Sündermann, Simon H, Jacobs, Stephan, Falk, Volkmar, and Kempfert, Jörg
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- 2022
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17. Partial ring annuloplasty in the management of mitral annular calcification.
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Akansel, Serdar, Kofler, Markus, Sündermann, Simon H., Van Praet, Karel M., Falk, Volkmar, and Kempfert, Jörg
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Mitral annular calcification (MAC) complicates the management of mitral valve (MV) disease, regardless of its etiology. Strategies to address MV surgery in MAC include two main options with their own pros and cons; respect and resect strategy. Here, we present a case of minimally‐invasive MV repair with partial annuloplasty in the management of noncircumferential MAC with respect to strategy. This technique may be an alternative option for rescuing high‐risk patients without extensive decalcification. [ABSTRACT FROM AUTHOR]
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- 2022
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18. Transcatheter mitral valve implantation in the ongoing structural heart revolution.
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Sá, Michel Pompeu, Ramlawi, Basel, Gray, William A., Malin, John H., Van den Eynde, Jef, Sicouri, Serge, Torregrossa, Gianluca, Klein, Christoph, Heil, Emanuel, Sündermann, Simon H., Emmerich, Anna, Kempfert, Jörg, Kofler, Markus, Falk, Volkmar, Unbehaun, Axel, and Van Praet, Karel M.
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Transcatheter mitral valve implantation (TMVI) has emerged as a less invasive approach potentially surmounting some of the current hurdles associated with transcatheter edge‐to‐edge repair and high‐risk mitral valve surgery. In this review, we aimed to outline the main scenarios in the TMVI field, highlight current and upcoming devices, and describe challenges and clinical results. Finally, we briefly discuss the future perspectives for this emerging field and how TMVI might further advance the field of transcatheter treatments of mitral valve disease. [ABSTRACT FROM AUTHOR]
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- 2022
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19. Learning three-dimensional aortic root assessment based on sparse annotations.
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Brosig, Johanna, Krüger, Nina, Khasyanova, Inna, Wamala, Isaac, Ivantsits, Matthias, Sündermann, Simon, Kempfert, Jörg, Heldmann, Stefan, and Hennemuth, Anja
- Published
- 2024
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20. Comparison of feasibility and results of frailty assessment methods prior to left ventricular assist device implantation.
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Roehrich, Luise, Sündermann, Simon H., Just, Isabell Anna, Kopp Fernandes, Laurenz, Stein, Julia, Solowjowa, Natalia, Mulzer, Johanna, Mueller, Marcus, Hummel, Manfred, Knierim, Jan, Potapov, Evgenij, Falk, Volkmar, and Schoenrath, Felix
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HEART assist devices ,FRAGILITY (Psychology) ,HEART failure patients - Abstract
Aims: Assessing frailty and sarcopenia is considered a valuable cornerstone of perioperative risk stratification in advanced heart failure patients. The lack of an international consensus on a diagnostic standard impedes its implementation in the clinical routine. This study aimed to compare the feasibility and prognostic impact of different assessment tools in patients undergoing continuous‐flow left ventricular assist device (cf‐LVAD) implantation. Methods and results: We prospectively compared feasibility and prognostic values of six frailty/sarcopenia assessment methods in 94 patients prior to cf‐LVAD implantation: bioelectrical impedance analysis (BIA), computed tomography (CT)‐based measurement of two muscle areas/body surface area [erector spinae muscle (TMESA/BSA) and iliopsoas muscle (TPA/BSA)], physical performance tests [grip strength, 6 min walk test (6MWT)] and Rockwood Clinical Frailty Scale (RCFS). Six‐month mortality and/or prolonged ventilation time >95 h was defined as the primary endpoint. BIA and CT showed full feasibility (100%); physical performance and RCFS was limited due to patients' clinical status (feasibility: 87% grip strength, 62% 6MWT, 88% RCFS). Phase angle derived by BIA showed the best results regarding the prognostic value for 6 month mortality and/or prolonged ventilation time >95 h (odds ratio (OR) 0.66 [95% confidence interval (CI): 0.46–0.92], P = 0.019; area under the curve (AUC) 0.65). It provided incremental value to the clinical risk assessment of EuroSCORE II: C‐index of the combined model was 0.75 [95% CI; 0.651–0.848] compared with C‐index of EuroSCORE II alone, which was 0.73 (95% CI: 0.633–0.835). Six‐month survival was decreased in patients with reduced body cell mass derived by BIA or reduced muscle area in the CT scan compared with patients with normal values: body cell mass 65% (95% CI: 51.8–81.6%) vs. 83% (95% CI: 74.0–93.9%); P = 0.03, TMESA/BSA 65% (95% CI: 51.2–82.2%) vs. 82% (95% CI: 73.2–93.0%); P = 0.032 and TPA/BSA 66% (95% CI: 53.7–81.0%) vs. 85% (95% CI: 75.0–95.8%); P = 0.035. Conclusions: Bioelectrical impedance analysis parameters and CT measurements were shown to be suitable to predict 6‐month mortality and/or prolonged ventilation time >95 h in patients with advanced heart failure prior to cf‐LVAD implantation. Phase angle had the best predictive capacity and sarcopenia diagnosed by reduced body cell mass in BIA or muscle area in CT was associated with a decreased 6 month survival. [ABSTRACT FROM AUTHOR]
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- 2022
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21. Endoaortic Balloon Occlusion During Minimally Invasive Mitral Valve Surgery.
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Van Praet, Karel M., Kofler, Markus, Sündermann, Simon H., and Kempfert, Jörg
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- 2022
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22. Cascaded neural network-based CT image processing for aortic root analysis.
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Krüger, Nina, Meyer, Alexander, Tautz, Lennart, Hüllebrand, Markus, Wamala, Isaac, Pullig, Marius, Kofler, Markus, Kempfert, Jörg, Sündermann, Simon, Falk, Volkmar, and Hennemuth, Anja
- Abstract
Purpose: Careful assessment of the aortic root is paramount to select an appropriate prosthesis for transcatheter aortic valve implantation (TAVI). Relevant information about the aortic root anatomy, such as the aortic annulus diameter, can be extracted from pre-interventional CT. In this work, we investigate a neural network-based approach for segmenting the aortic root as a basis for obtaining these parameters. Methods: To support valve prosthesis selection, geometric measures of the aortic root are extracted from the patient's CT scan using a cascade of convolutional neural networks (CNNs). First, the image is reduced to the aortic root, valve, and left ventricular outflow tract (LVOT); within that subimage, the aortic valve and ascending aorta are segmented; and finally, the region around the aortic annulus. From the segmented annulus region, we infer the annulus orientation using principal component analysis (PCA). The area-derived diameter of the annulus is approximated based on the segmentation of the aortic root and LVOT and the plane orientation resulting from the PCA. Results: The cascade of CNNs was trained using 90 expert-annotated contrast-enhanced CT scans routinely acquired for TAVI planning. Segmentation of the aorta and valve within the region of interest achieved an F1 score of 0.94 on the test set of 36 patients. The area-derived diameter within the annulus region was determined with a mean error below 2 mm between the automatic measurement and the diameter derived from annotations. The calculated diameters and resulting errors are comparable to published results of alternative approaches. Conclusions: The cascaded neural network approach enabled the assessment of the aortic root with a relatively small training set. The processing time amounts to 30 s per patient, facilitating time-efficient, reproducible measurements. An extended training data set, including different levels of calcification or special cases (e.g., pre-implanted valves), could further improve this method's applicability and robustness. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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23. Using Position‐Based Dynamics for Simulating Mitral Valve Closure and Repair Procedures.
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Walczak, Lars, Georgii, Joachim, Tautz, Lennart, Neugebauer, Mathias, Wamala, Isaac, Sündermann, Simon, Falk, Volkmar, and Hennemuth, Anja
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MITRAL valve ,OPERATIVE surgery - Abstract
To achieve the best treatment of mitral valve disease in a patient, surgeons aim to optimally combine complementary surgical techniques. Image‐based in silico simulation as well as visualization of the mitral valve dynamics can support the visual analysis of the patient‐specific valvular dynamics and enable an exploration of different therapy options. The usage in a time‐constrained clinical environment requires a mitral valve model that is cost‐effective, easy to set up, parameterize and evaluate. Working towards this goal, we develop a simplified model of the mitral valve and analyse its applicability for the sketched use‐case. We propose a novel approach to simulate the mitral valve with position‐based dynamics. The resulting mitral valve model can be deformed to simulate the closing and opening, and incorporate changes caused by virtual interventions in the simulation. Ten mitral valves were reconstructed from transesophageal echocardiogram sequences of patients with normal and abnormal physiology for evaluation. Simulation results showed good agreements with expert annotations of the original image data and reproduced valve closure in all cases. In four of five pathological cases, abnormal closing behaviour was correctly reproduced. In future research, we aim to improve the parameterization of the model in terms of biomechanical correctness and perform a more extensive validation. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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24. Minimally invasive surgery versus sternotomy in native mitral valve endocarditis: a matched comparison.
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Kofler, Markus, Praet, Karel M Van, Schambach, Julie, Akansel, Serdar, Sündermann, Simon, Schönrath, Felix, Jacobs, Stephan, Falk, Volkmar, and Kempfert, Jörg
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MITRAL valve ,MINIMALLY invasive procedures ,RED blood cell transfusion ,EXTUBATION ,ENDOCARDITIS ,INFECTIVE endocarditis ,PROPENSITY score matching - Abstract
Open in new tab Download slide Open in new tab Download slide OBJECTIVES The present study compared the clinical outcomes between minimally invasive surgery (MIS) and median sternotomy (MS) in patients with native mitral valve infective endocarditis. METHODS From 2009 to 2019, a total of 154 patients with acute (n = 131, 85%) or subacute (n = 23, 15%) native mitral valve infective endocarditis were included in the study. One-to-one nearest neighbour propensity score matching considering endocarditis severity using the dedicated De Feo score and 19 other clinically relevant baseline variables resulted in a population of 39 matched pairs. The matched cohort was investigated regarding operative and postoperative outcomes. RESULTS Both groups showed similar results regarding cardiopulmonary bypass time [MIS: 96 min (77–138), MS: 99 min (88–127); P = 0.780] and aortic cross-clamp time [MIS: 64 min (54–90), MS: 65 min (59–83); P = 0.563], whereas overall operative time was shorter through minimally invasive access [MIS: 138 min (112–196), MS: 187 min (175–230); P = 0.005]. Although the rate of revision for bleeding was similar in both groups [MIS: 12.8% (n = 5), MS: 10.3% (n = 4); P = 1.000], MIS was associated with fewer red blood cell unit transfusions [MIS: 1 unit (0–4), MS: 4 units (2–10); P = 0.001] and fewer fresh frozen plasma unit transfusions [MIS: 0 units (0–0), MS: 1 unit (0–5); P = 0.002]. MIS was associated with a shorter ventilation time [MIS: 708 min (429–1236), MS: 1440 min (659–4411); P = 0.024] and a lower rate of reintubation after extubation [MIS: 5.1% (n = 2), MS: 25.6% (n = 10); P = 0.021]. CONCLUSIONS In patients suffering from native mitral valve infective endocarditis, MIS provides significant clinical benefits over sternotomy in selected patients. Subject collection 117, 121. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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25. Real-Time Ventricular Volume Measured Using the Intracardiac Electromyogram.
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Schmid Daners, Marianne, Hall, Sophie, Sündermann, Simon, Cesarovic, Nikola, Kron, Mareike, Falk, Volkmar, Starck, Christoph, Meboldt, Mirko, and Dual, Seraina A.
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- 2021
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26. Propensity matched long-term analysis of mechanical versus stentless aortic valve replacement in the younger patient.
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Christ, Torsten, Borck, Robin, Dushe, Simon, Sündermann, Simon Harald, Falk, Volkmar, and Grubitzsch, Herko
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AORTIC valve transplantation ,MECHANICAL hearts ,REOPERATION ,AORTIC stenosis ,CONGENITAL heart disease ,HOSPITAL mortality ,ADULTS - Abstract
Open in new tab Download slide Open in new tab Download slide OBJECTIVES The choice of prosthesis for aortic valve replacement (AVR) in younger patients remains controversial. Stentless AVR was introduced 3 decades ago, with the aim of better haemodynamics and durability than stented xenografts. The objective of this analysis was to compare the long-term outcomes to mechanical prostheses in younger patients (age ≤60 years). METHODS All adult patients who underwent AVR due to aortic valve stenosis and/or insufficiency between 1993 and 2002 were identified. After the exclusion of patients with congenital heart defects, aortic dissections and Ross-procedures, 158 patients with stentless valves and 226 patients with bi-leaflet mechanical valves were finally included in this analysis. Sixty-six patient pairs could be included in a propensity matched analysis. Mortality and morbidity including stroke, bleeding, endocarditis and reoperation were analysed. RESULTS Group baseline characteristics and operative data did not differ significantly after propensity matching. Hospital mortality was 0.0% in the stentless and 1.5% in the mechanical group. Total patient years/median follow-up was 2029.1/15.4 years (completeness: 100.0%, range: 0–25 years). After 20 years, actuarial survival was 47.0 ± 6.4% in the stentless and 53.3 ± 6.6% in mechanical group (P = 0.69). Bleeding, endocarditis and stroke occurred rarely and did not differ significantly between groups. After 20 years, actuarial overall freedom-from-reoperation was 45.1 ± 8.2% in the stentless group and 90.4 ± 4.1% in the mechanical group (P < 0.001). Hospital mortality while reoperation was 7.4% in the stentless group and 0% in the mechanical group (P = 1.0) CONCLUSIONS Long-term morbidity and mortality of stentless and mechanical aortic valves were statistically not different besides a significantly higher reoperation rate after stentless AVR combined with a probably higher risk of in-hospital mortality. Thus, mechanical AVR should remain the procedure of choice in younger patients. [ABSTRACT FROM AUTHOR]
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- 2021
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27. SLL-PEEP Ventilation to Improve Exposure in Minimally Invasive Right Anterolateral Minithoracotomy Aortic Valve Replacement.
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Richter, Gregor, Van Praet, Karel M., Hommel, Matthias, Sündermann, Simon H., Kofler, Markus, Meyer, Alexander, Unbehaun, Axel, Starck, Christoph, Jacobs, Stephan, Falk, Volkmar, and Kempfert, Jörg
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- 2021
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28. State of the Art Review: Surgical Treatment of Acute Type A Aortic Dissection.
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PITTS, LEONARD, MONTAGNER, MATTEO, KOFLER, MARKUS, VAN PRAET, KAREL M., HECK, ROLAND, BUZ, SEMIH, KURZ, STEPHAN D., SÜNDERMANN, SIMON, HOMMEL, MATTHIAS, FALK, VOLKMAR, and KEMPFERT, JÖRG
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- 2021
29. Virtual reality in cardiac interventions—New tools or new toys?
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Sündermann, Simon H., Hennemuth, Anja, and Kempfert, Jörg
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Improvementsin medical imaging and a steady increase in computing power are leading to new possibilities in the field of cardiovascular interventions. Interventions can be planned in advance in greater detail, even to the point of simulating procedures. Nevertheless, all techniques are at an early stage of development. It is of utmost importance that tools, especially if they can be used as decision support are intensively validated and their accuracy is demonstrated. In our commentary, we summarize current techniques for impprovements in planning and guiding of procedures, but also critically discuss the downsides of these techniques. Following the work of Kenichi and colleagues, we also discuss necessary steps in advancing new tools and techniques, particularly as they are used in routine clinical practice. We also discuss the role of artificial intelligence, which could play a crucial role in this context in the future. [ABSTRACT FROM AUTHOR]
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- 2022
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30. Real-time intraoperative co-registration of transesophageal echocardiography with fluoroscopy facilitates transcatheter mitral valve-in-valve implantation in cases of invisible degenerated bioprosthetic valves.
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Wamala, Isaac, Unbehaun, Axel, Klein, Christoph, Kukucka, Marian, Eggert-Doktor, Dirk, Buz, Semih, Stein, Julia, Sündermann, Simon, Falk, Volkmar, and Kempfert, Jörg
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- 2021
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31. A new calcium score to predict paravalvular leak in transcatheter aortic valve implantation.
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Kofler, Markus, Meyer, Alexander, Schwartz, Julian, Sündermann, Simon, Penkalla, Adam, Solowjowa, Natalia, Klein, Christoph, Unbehaun, Axel, Falk, Volkmar, and Kempfert, Jörg
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HEART valve prosthesis implantation ,CALCIUM ,RECEIVER operating characteristic curves ,AORTIC valve ,REGRESSION analysis - Abstract
Open in new tab Download slide Open in new tab Download slide OBJECTIVES The present study sought to develop a reliable calcium score (Ca-score) to predict paravalvular leak (PVL) in patients undergoing transcatheter aortic valve (AV) implantation. METHODS A total of 965 patients were prospectively included from 2012 to 2019. Preprocedural contrast-media-enhanced computed tomography scans were analysed regarding the amount of AV cusp calcification and the presence of upper and lower left ventricular outflow tract calcification. The calcium volume threshold of each AV cusp [non-coronary cusp (NCC); left coronary cusp (LCC); right coronary cusp (RCC)] with optimal PVL prediction was defined using the Youden index value derived from receiver operating characteristic analysis. The final score was developed based on the multivariable regression analysis, while individual variables were weighted based on their corresponding odds ratio. RESULTS The AV calcium volume threshold with optimal PVL prediction was 733.6, 296.0 and 131.2 mm
3 for the NCC, RCC and LCC respectively. Overall, calcification of the upper left ventricular outflow tract was present in 233 (23%), 111 (12%) and 304 (32%) of patients below the NCC, RCC and LCC respectively, while 260 (27%), 44 (5%) and 217 (23%) patients suffered from calcification under the NCC, RCC and LCC, respectively. A total Ca-score of ≥4 was present in 356 (37%) of patients and was independently associated with ≥ mild PVL [odds ratio 3.662; 95% confidence interval (2.740–4.911); P < 0.001]. The area under the curve of the Ca-score was 0.713 [95% confidence interval (0.678–0.748); P < 0.001]. CONCLUSION The provided Ca-score independently correlates with the development of PVL and improves risk stratification in patients undergoing transcatheter AV implantation. [ABSTRACT FROM AUTHOR]- Published
- 2021
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32. Mitral valve surgery: current status and future prospects of the minimally invasive approach.
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Van Praet, Karel M., Kempfert, Jörg, Jacobs, Stephan, Stamm, Christof, Akansel, Serdar, Kofler, Markus, Sündermann, Simon H., Nazari Shafti, Timo Z., Jakobs, Katharina, Holzendorf, Stefan, Unbehaun, Axel, and Falk, Volkmar
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MITRAL valve surgery ,MITRAL valve ,ANESTHESIOLOGISTS ,ENDOSCOPIC surgery ,PATIENT safety - Abstract
Introduction: During the past five years the approach to procedural planning, operative techniques and perfusion strategies for minimally invasive mitral valve surgery (MIMVS) has evolved. With the goal to provide a maximum of patient safety the procedure has been modified according to individual patient characteristics and is largely based on preoperative imaging. Areas covered: In this review article we describe the important factors in image based therapy planning and simulation, different access strategies, the operative key-steps, a rationale use of devices, and highlight a few future developments in the field of MIMVS. Published studies were identified through pearl growing, citation chasing, a search of PubMed using the systematic review methods filter, and the authors' topic knowledge. Expert opinion: With the help of expert teams including surgeons specialized in mitral repair, anesthesiologists and perfusionists a broad spectrum of mitral valve pathologies and related pathologies can be treated with excellent functional outcomes. Avoiding procedure related complications is the key for success for any MIMVS program. [ABSTRACT FROM AUTHOR]
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- 2021
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33. A Novel Hybrid Membrane VAD as First Step Toward Hemocompatible Blood Propulsion.
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Ferrari, Aldo, Giampietro, Costanza, Bachmann, Björn, Bernardi, Laura, Bezuidenhhout, Deon, Ermanni, Paolo, Hopf, Raoul, Kitz, Sarah, Kress, Gerald, Loosli, Christian, Marina, Vita, Meboldt, Mirko, Pellegrini, Giovanni, Poulikakos, Dimos, Rebholz, Mathias, Schmid Daners, Marianne, Schmidt, Tanja, Starck, Christoph, Stefopoulos, Georgios, and Sündermann, Simon
- Abstract
Heart failure is a raising cause of mortality. Heart transplantation and ventricular assist device (VAD) support represent the only available lifelines for end stage disease. In the context of donor organ shortage, the future role of VAD as destination therapy is emerging. Yet, major drawbacks are connected to the long-term implantation of current devices. Poor VAD hemocompatibility exposes the patient to life-threatening events, including haemorrhagic syndromes and thrombosis. Here, we introduce a new concept of artificial support, the Hybrid Membrane VAD, as a first-of-its-kind pump prototype enabling physiological blood propulsion through the cyclic actuation of a hyperelastic membrane, enabling the protection from the thrombogenic interaction between blood and the implant materials. The centre of the luminal membrane surface displays a rationally-developed surface topography interfering with flow to support a living endothelium. The precast cell layer survives to a range of dynamically changing pump actuating conditions i.e., actuation frequency from 1 to 4 Hz, stroke volume from 12 to 30 mL, and support duration up to 313 min, which are tested both in vitro and in vivo, ensuring the full retention of tissue integrity and connectivity under challenging conditions. In summary, the presented results constitute a proof of principle for the Hybrid Membrane VAD concept and represent the basis for its future development towards clinical validation. [ABSTRACT FROM AUTHOR]
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- 2021
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34. Minithoracotomy versus full sternotomy for isolated aortic valve replacement: Propensity matched data from two centers.
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Meyer, Alexander, Kampen, Antonia, Kiefer, Philipp, Sündermann, Simon, Van Praet, Karel M., Borger, Michael A., Falk, Volkmar, Kempfert, Jörg, and van Kampen, Antonia
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AORTIC valve transplantation ,THORACOTOMY ,BLOOD platelet transfusion ,MINIMALLY invasive procedures ,PROPENSITY score matching ,ATRIAL fibrillation ,CARDIOPULMONARY bypass ,AORTIC valve surgery ,LENGTH of stay in hospitals ,THORACIC surgery ,ENDOSCOPIC surgery ,RETROSPECTIVE studies ,TREATMENT effectiveness ,PROSTHETIC heart valves ,PROBABILITY theory - Abstract
Background: Minimally invasive approaches to isolated aortic valve replacement (AVR) continue to gain popularity. This study compares outcomes of AVR through right anterolateral thoracotomy (RALT) to those of AVR through full median sternotomy (MS).Methods: Outcomes of two propensity-matched groups of 85 each, out of 250 patients that underwent isolated AVR through RALT or MS at our two institutions, were compared in a retrospective study.Results: Propensity score matching resulted in 85 matched pairs with balanced preoperative characteristics. Procedure times were significantly shorter in the RALT group (median difference: 13 min [-25 to -0.5]; p = .039), cardiopulmonary bypass times were longer (median difference: 17 min [10-23.5]; p = < .001) and ventilation times shorter (median difference: 259 min [-390 to -122.5]; p = < .001). There was no significant difference in aortic cross-clamp times (median difference: 1.5 min [-3.5 to 6.5]; p = .573). The RALT group had lower rates of perioperative platelet transfusions (odds ratio [OR] = 0.00 [0.00-0.59]; p = .0078) and postoperative pneumonia (OR = 0.10 [0.00-0.70]; p = .012), as well as shorter hospitalization times (median difference: 2.5 days [-4.5 to -1]; p = .005). There were no significant differences regarding paravalvular leakage (p = .25), postoperative stroke (p = 1), postoperative atrial fibrillation (p = .12) or 1-year-mortality (p = 1).Conclusions: This study found RALT to be an equally safe approach to surgical AVR as MS. Furthermore, RALT showed advantages regarding important aspects of postoperative recovery, especially concerning pulmonary function. [ABSTRACT FROM AUTHOR]- Published
- 2021
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35. Continuous Heart Volume Monitoring by Fully Implantable Soft Strain Sensor.
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Dual, Seraina A., Llerena Zambrano, Byron, Sündermann, Simon, Cesarovic, Nikola, Kron, Mareike, Magkoutas, Konstantinos, Hengsteler, Julian, Falk, Volkmar, Starck, Christoph, Meboldt, Mirko, Vörös, János, and Schmid Daners, Marianne
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- 2020
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36. Control of ventricular unloading using an electrocardiogram‐synchronized pulsatile ventricular assist device under high stroke ratios.
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Magkoutas, Konstantinos, Rebholz, Mathias, Sündermann, Simon, Alogna, Alessio, Faragli, Alessandro, Falk, Volkmar, Meboldt, Mirko, and Schmid Daners, Marianne
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HEART assist devices ,PULSATILE flow ,HEART beat ,MECHANICAL failures ,BLOOD flow ,STROKE - Abstract
Pulsatile ventricular assist devices (pVADs) yield a blood flow that imitates the pulsatile flow of the heart and, therefore, could diminish the adverse events related to the continuous flow provided by the ventricular assist devices that are commonly used. However, their intrinsic characteristics of larger size and higher weight set a burden to their implantation, that along with the frequent mechanical failures and thrombosis events, reduce the usage of pVADs in the clinical environment. In this study, we investigated the possibility to reduce the pump size by using high pump stroke ratios while maintaining the ability to control the hemodynamics of the cardiovascular system (CVS). In vitro and in vivo experiments were conducted with a custom pVAD implemented on a hybrid mock circulation system and in five sheep, respectively. The actuation of the pVAD was synchronized with the heartbeat. Variations of the pump stroke ratio, time delay between the pump stroke and the heart stroke, as well as duration of the pump systole in respect to the total cardiac cycle duration were used to evaluate the effects of various pump settings on the hemodynamics of the CVS. The results suggest that by varying the operating settings of the pVAD, a pulsatile flow that provides physiological hemodynamic parameters, as well as a control over the hemodynamic parameters, can be achieved. Additionally, by employing high pump stroke ratios, the size of the pVAD can be significantly reduced; however, at those high pump stroke ratios, the effect of the other pump parameters diminishes. [ABSTRACT FROM AUTHOR]
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- 2020
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37. Minimally invasive surgical aortic valve replacement: The RALT approach.
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Praet, Karel M., Kampen, Antonia, Kofler, Markus, Richter, Gregor, Sündermann, Simon H., Meyer, Alexander, Unbehaun, Axel, Kurz, Stephan, Jacobs, Stephan, Falk, Volkmar, Kempfert, Jörg, Van Praet, Karel M, and van Kampen, Antonia
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AORTIC valve transplantation ,THORACOTOMY ,MINIMALLY invasive procedures ,OPERATIVE surgery ,AORTIC stenosis - Abstract
Less-invasive techniques for cardiothoracic surgical procedures are designed to limit surgical trauma, but the technical requirements and preoperative planning are more demanding than those for conventional sternotomy. Patient selection, interdisciplinary collaboration, and surgical skills are key factors for procedural success. Aortic valve replacement is frequently performed through an upper hemisternotomy, but the right anterior minithoracotomy represents an even less traumatic, technical advancement. Preoperative assessment of the ascending aorta in relation to the sternum is mandatory to select patients and the intercostal access site. This description of the surgical technique focuses on the specific procedural details including the obligatory planning with computed tomography and our cannulation strategy. We also sought to define the anatomical ascending aorta-sternal relationship, as it is of utmost importance in preoperative computed tomographic planning. [ABSTRACT FROM AUTHOR]
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- 2020
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38. Transcatheter aortic valve implantation and its impact on mitral valve geometry and function.
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Meyer, Alexander, Greve, Dustin, Unbehaun, Axel, Kofler, Markus, Kukucka, Marian, Klein, Christoph, Knierim, Jan, Emmert, Maximilian Y., Falk, Volkmar, Kempfert, Jörg, and Sündermann, Simon H.
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MITRAL valve ,TRANSESOPHAGEAL echocardiography ,HEART valve prosthesis implantation ,MITRAL valve insufficiency ,GEOMETRY ,AORTIC valve transplantation ,AORTIC valve surgery ,MITRAL valve surgery ,PROSTHETICS ,AORTIC stenosis ,TREATMENT effectiveness ,PROSTHETIC heart valves ,IMPACT of Event Scale ,AORTIC valve - Abstract
Background: The aim of this study was to evaluate the impact of transcatheter aortic valve implantation (TAVI) on mitral valve geometry and function.Methods: Eighty-four patients underwent TAVI. Forty-four (52%) patients received a balloon-expandable valve and 40 (48%) were implanted with a self-expandable valve. All patients underwent three-dimensional-volumetric transesophageal echocardiography of the mitral valve before and immediately after TAVI. A dedicated software was used for assisted semiautomatic measurement of mitral annular geometry.Results: During systole, the anterior to posterior (AP) diameter was significantly reduced after the procedure (3.4 ± 0.5 cm vs 3.2 ± 0.5 cm; P < .05). The mitral annular area (10.8 ± 2.8cm2 vs 9.9 ± 2.6cm2 ; P < .05) as well as the tenting area (1.6 ± 0.7 cm2 vs 1.2 ± 0.6 cm2 ; P < .001) measured at mid-systole were reduced after TAVI. Diastolic measures were similar. Patients treated with balloon-expandable valves showed a significantly larger reduction in the AP diameter compared to self-expandable valves (-0.25 cm vs -0.11 cm; P < .05). The reduction of the annular area was higher in the balloon-expandable group (-1.2 ± 1.59 vs -0.22 ± 1.41; P < .05). Grade of mitral regurgitation did improve or remained stable after TAVI.Conclusion: TAVI significantly impacts the mitral valve and mitral annular geometry and morphology. The choice of the prosthesis (balloon- vs self-expandable) may be relevant for those changes. [ABSTRACT FROM AUTHOR]- Published
- 2020
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39. Reliability and Influence on Decision Making of fully-automated vs. semi-automated Software Packages for Procedural Planning in TAVI.
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Meyer, Alexander, Kofler, Markus, Montagner, Matteo, Unbehaun, Axel, Sündermann, Simon, Buz, Semih, Klein, Christoph, Stamm, Christof, Solowjowa, Natalia, Emmert, Maximilian Y., Falk, Volkmar, and Kempfert, Jörg
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HEART valve prosthesis implantation ,HEALTH outcome assessment ,DECISION making ,MEDICAL software ,PATIENT selection - Abstract
Precise procedural planning is crucial to achieve excellent results in patients undergoing Transcatheter aortic valve implantation (TAVI). The aim of this study was to compare the semi-automated 3mensio (3 m) software to the fully-automated HeartNavigator3 (HN) software. We randomly selected 100 patients from our in-house TAVI-registry and compared aortic annulus and perimeter as well as coronary distances between 3m-measurements and post-hoc HN-measurements. Finally, we retrospectively simulated prosthesis choice based on HN-measurements and analyzed the differences compared to routinely used 3 m based strategy. We observed significant differences between the two software packages regarding area (3 m 464 ± 88 mm², HN 482 ± 96 mm², p < 0.001), perimeter (3 m 77 ± 7 mm, HN 79 ± 8 mm, p < 0.001) and coronary distances (LCA: 3 m 13 ± 3 mm, HN 12 ± 3 mm, p < 0.001; RCA: 3 m 16 ± 3 mm, HN 15 ± 3 mm, p < 0.001). Prosthesis choice simulation based on newly obtained HN-measurements would have led to a decision change in 18% of patients, with a further reduction to 4% following manual adjustment of HN-measurements. The fully-automatic HN-software provides higher values for annular metrics and lower annulus-to-coronary-ostia distances compared to 3m-software. Measurement differences did not influence clinical outcome. Both, the HN-software and the 3m-software are sophisticated, reliable and easy to use for the clinician. Manual adjustment of HN-measurements may increase precision in complex aortic annulus anatomy. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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40. DL-based segmentation of endoscopic scenes for mitral valve repair.
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Ivantsits, Matthias, Tautz, Lennart, Sündermann, Simon, Wamala, Isaac, Kempfert, Jörg, Kuehne, Titus, Falk, Volkmar, and Hennemuth, Anja
- Abstract
Minimally invasive surgery is increasingly utilized for mitral valve repair and replacement. The intervention is performed with an endoscopic field of view on the arrested heart. Extracting the necessary information from the live endoscopic video stream is challenging due to the moving camera position, the high variability of defects, and occlusion of structures by instruments. During such minimally invasive interventions there is no time to segment regions of interest manually. We propose a real-time-capable deep-learning-based approach to detect and segment the relevant anatomical structures and instruments. For the universal deployment of the proposed solution, we evaluate them on pixel accuracy as well as distance measurements of the detected contours. The U-Net, Google's DeepLab v3, and the Obelisk-Net models are cross-validated, with DeepLab showing superior results in pixel accuracy and distance measurements. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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41. Intraventricular flow features and cardiac mechano-energetics after mitral valve interventions – feasibility of an isolated heart model.
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Vellguth, Katharina, Sündermann, Simon, Escher, Andreas, Bierewirtz, Tim, Schmidt, Tanja, Alogna, Alessio, Kertzscher, Ulrich, Goubergrits, Leonid, Fraser, Katharine H., and Granegger, Marcus
- Abstract
The aim of this work was the development of an isolated heart setup to delineate the interactions between intraventricular flow features, hemodynamic parameters and mechano-energetics after certain mitral valve therapies. Five porcine hearts were explanted and prepared for (i) edge-to-edge mitral valve repair, (ii) implantation of a rotatable biscupid mechanical valve prosthesis. Flow structures were visualized using echocardiography while hemodynamics was recorded in terms of pressures, flow rates and ventricular volume. Hemodynamic and cardiac mechano-energetics implied a marginal effect (<5%) of alternating leaflet orientation on ventricular pre-load and stroke work. After edge-to-edge repair, substantial variations in flow structures were observed. Beside promoting profound insights into fundamental physiologic mechanisms, the setup may be used for validation of computer aided therapy planning tools. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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42. Combining position-based dynamics and gradient vector flow for 4D mitral valve segmentation in TEE sequences.
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Tautz, Lennart, Walczak, Lars, Georgii, Joachim, Jazaerli, Amer, Vellguth, Katharina, Wamala, Isaac, Sündermann, Simon, Falk, Volkmar, and Hennemuth, Anja
- Abstract
Purpose: For planning and guidance of minimally invasive mitral valve repair procedures, 3D+t transesophageal echocardiography (TEE) sequences are acquired before and after the intervention. The valve is then visually and quantitatively assessed in selected phases. To enable a quantitative assessment of valve geometry and pathological properties in all heart phases, as well as the changes achieved through surgery, we aim to provide a new 4D segmentation method. Methods: We propose a tracking-based approach combining gradient vector flow (GVF) and position-based dynamics (PBD). An open-state surface model of the valve is propagated through time to the closed state, attracted by the GVF field of the leaflet area. The PBD method ensures topological consistency during deformation. For evaluation, one expert in cardiac surgery annotated the closed-state leaflets in 10 TEE sequences of patients with normal and abnormal mitral valves, and defined the corresponding open-state models. Results: The average point-to-surface distance between the manual annotations and the final tracked model was 1.00 mm ± 1.08 mm . Qualitatively, four cases were satisfactory, five passable and one unsatisfactory. Each sequence could be segmented in 2–6 min. Conclusion: Our approach enables to segment the mitral valve in 4D TEE image data with normal and pathological valve closing behavior. With this method, in addition to the quantification of the remaining orifice area, shape and dimensions of the coaptation zone can be analyzed and considered for planning and surgical result assessment. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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43. An overview of surgical treatment modalities and emerging transcatheter interventions in the management of tricuspid valve regurgitation.
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Van Praet, Karel M., Stamm, Christof, Starck, Christoph T., Sündermann, Simon, Meyer, Alexander, Montagner, Matteo, Nazari Shafti, Timo Z., Unbehaun, Axel, Jacobs, Stephan, Falk, Volkmar, Kempfert, Jörg, Sündermann, Simon, and Kempfert, Jörg
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TRICUSPID valve insufficiency ,TRICUSPID valve transplantation ,TRICUSPID valve surgery ,SURGICAL complications ,PATHOLOGICAL physiology ,PROSTHETIC heart valves ,HEART valve diseases ,TREATMENT effectiveness - Abstract
Introduction: Tricuspid valve regurgitation (TR) is frequently encountered and is most often functional (FTR) in nature. Surgical tricuspid valve (TV) treatment is well established in specialized centers. While transcatheter therapy for other valve disease is well established, interventional treatment of TV disease is still in its early stages. With the increasing adoption of catheter-based treatments, there is a growing interest in and need for interventional treatments for TR. An extensive literature search was methodologically performed aiming for an integrative review paper. Areas covered: This review will discuss the current surgical treatment modalities and emerging transcatheter interventions in the management of TR. Furthermore, this review will describe the pathophysiology of functional tricuspid regurgitation (FTR), and the new 2017 ESC/EACTS guidelines for the management of TR. Finally, a five-year view into the future will be stated. Expert commentary: At their center, the authors have an aggressive approach for the treatment of FTR owing to its significant impact on perioperative as well as late postoperative morbidity and mortality. The authors perform TV ring annuloplasty when substantial annular dilation (≥45mm) is observed. In the future, percutaneous TV technologies might become an alternative option to treat TR patients with high surgical risk selectively. [ABSTRACT FROM AUTHOR]- Published
- 2018
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44. User-dependent variability in mitral valve segmentation and its impact on CFD-computed hemodynamic parameters.
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Vellguth, Katharina, Brüning, Jan, Tautz, Lennart, Degener, Franziska, Wamala, Isaac, Sündermann, Simon, Kertzscher, Ulrich, Kuehne, Titus, Hennemuth, Anja, Falk, Volkmar, and Goubergrits, Leonid
- Abstract
Purpose: While novel tools for segmentation of the mitral valve are often based on automatic image processing, they mostly require manual interaction by a proficient user. Those segmentations are essential for numerical support of mitral valve treatment using computational fluid dynamics, where the reconstructed geometry is incorporated into a simulation domain. To quantify the uncertainty and reliability of hemodynamic simulations, it is crucial to examine the influence of user-dependent variability in valve segmentation. Methods: Previously, the inter-user variability of landmarks in mitral valve segmentation was investigated. Here, the inter-user variability of geometric parameters of the mitral valve, projected orifice area (OA) and projected annulus area (AA), is investigated for 10 mitral valve geometries, each segmented by three users. Furthermore, the propagation of those variations into numerically calculated hemodynamics, i.e., the blood flow velocity, was investigated. Results: Among the three geometric valve parameters, AA was least user-dependent. Almost all deviations to the mean were below 10%. Larger variations were observed for OA. Variations observed for the numerically calculated hemodynamics were in the same order of magnitude as those of geometric parameters. No correlation between variation of geometric parameters and variation of calculated hemodynamic parameters was found. Conclusion: Errors introduced due to the user-dependency were of the same size as the variations of calculated hemodynamics. The variation was thereby of the same scale as deviations in clinical measurements of blood flow velocity using Doppler echocardiography. Since no correlation between geometric and hemodynamic uncertainty was found, further investigation of the complex relationship between anatomy, leaflet shape and flow is necessary. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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45. Virtual downsizing for decision support in mitral valve repair.
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Neugebauer, Mathias, Tautz, Lennart, Hüllebrand, Markus, Sündermann, Simon, Degener, Franziska, Goubergrits, Leonid, Kühne, Titus, Falk, Volkmar, and Hennemuth, Anja
- Abstract
Purpose: Various options are available for the treatment of mitral valve insufficiency, including reconstructive approaches such as annulus correction through ring implants. The correct choice of general therapy and implant is relevant for an optimal outcome. Additional to guidelines, decision support systems (DSS) can provide decision aid by means of virtual intervention planning and predictive simulations. Our approach on virtual downsizing is one of the virtual intervention tools that are part of the DSS workflow. It allows for emulating a ring implantation based on patient-specific lumen geometry and vendor-specific implants.Methods: Our approach is fully automatic and relies on a lumen mask and an annulus contour as inputs. Both are acquired from previous DSS workflow steps. A virtual surface- and contour-based model of a vendor-specific ring design (26-40 mm) is generated. For each case, the ring geometry is positioned with respect to the original, patient-specific annulus and additional anatomical landmarks. The lumen mesh is parameterized to allow for a vertex-based deformation with respect to the user-defined annulus. Derived from post-interventional observations, specific deformation schemes are applied to atrium and ventricle and the lumen mesh is altered with respect to the ring location.Results: For quantitative evaluation, the surface distance between the deformed lumen mesh and segmented post-operative echo lumen close to the annulus was computed for 11 datasets. The results indicate a good agreement. An arbitrary subset of six datasets was used for a qualitative evaluation of the complete lumen. Two domain experts compared the deformed lumen mesh with post-interventional echo images. All deformations were deemed plausible.Conclusion: Our approach on virtual downsizing allows for an automatic creation of plausible lumen deformations. As it takes only a few seconds to generate results, it can be added to a virtual intervention toolset without unnecessarily increasing the pipeline complexity. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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46. Body donation as a grateful gift for a long and active life with a Björk‐Shiley valve.
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Rudolph, Kevin, Galvez, Carlos, Chang, Julie, Wu, Anette, Gölkel, Camilla, Sündermann, Simon H., and Kielstein, Heike
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LONGEVITY ,VOLUNTEER fire fighters ,VALVES ,CELL anatomy ,AORTIC valve - Abstract
An 87‐year‐old patient donated his body to the Institute of Anatomy and Cell Biology in gratefulness for the longevity of a Björk‐Shiley convexo‐concave (BSCC) prosthetic aortic valve, implanted 34 years ago. The dissection of the enlarged heart showed no major signs of thrombosis, malignant fibrosis, or any other relevant issue that could potentially lead to valve failure as in other patients. Despite the reported high mortality rate of the earlier designs, especially of the BSCC valves, some patients survived for longer than expected. In more than 34 years after the BSCC valve implantation, the patient was a very active and lively man, working both as full‐time and volunteer firefighter. The lifespan of this BSCC valve is among the longest reported. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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47. Surgical explantation of a partially detached cardioband device.
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Akansel, Serdar, Sündermann, Simon H., Kofler, Markus, Emmerich, Anna, Falk, Volkmar, and Kempfert, Jörg
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MITRAL valve insufficiency ,MITRAL valve surgery ,MITRAL valve - Abstract
Transcatheter repair systems are becoming increasingly popular as a potential solution for high-risk and inoperable patients with mitral regurgitation. The cardioband (Edwards Lifesciences, Irvine, California) is a transcatheter direct annuloplasty device, based on the concept of an undersized ring annuloplasty. We report a case of minimally invasive surgical explantation of a failed cardioband device 21 months after its implantation. Intraoperatively, it was found that three anchors of the cardioband device were detached from the posterior annulus at P2. In this report, a "cut and unscrew" technique with some tips and tricks is presented for the removal of the device. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
48. Extraction of open-state mitral valve geometry from CT volumes.
- Author
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Tautz, Lennart, Neugebauer, Mathias, Hüllebrand, Markus, Vellguth, Katharina, Degener, Franziska, Sündermann, Simon, Wamala, Isaac, Goubergrits, Leonid, Kuehne, Titus, Falk, Volkmar, and Hennemuth, Anja
- Abstract
Purpose: The importance of mitral valve therapies is rising due to an aging population. Visualization and quantification of the valve anatomy from image acquisitions is an essential component of surgical and interventional planning. The segmentation of the mitral valve from computed tomography (CT) acquisitions is challenging due to high variation in appearance and visibility across subjects. We present a novel semi-automatic approach to segment the open-state valve in 3D CT volumes that combines user-defined landmarks to an initial valve model which is automatically adapted to the image information, even if the image data provide only partial visibility of the valve.Methods: Context information and automatic view initialization are derived from segmentation of the left heart lumina, which incorporates topological, shape and regional information. The valve model is initialized with user-defined landmarks in views generated from the context segmentation and then adapted to the image data in an active surface approach guided by landmarks derived from sheetness analysis. The resulting model is refined by user landmarks.Results: For evaluation, three clinicians segmented the open valve in 10 CT volumes of patients with mitral valve insufficiency. Despite notable differences in landmark definition, the resulting valve meshes were overall similar in appearance, with a mean surface distance of 1.62±2.10
mm. Each volume could be segmented in 5-22 min.Conclusions: Our approach enables an expert user to easily segment the open mitral valve in CT data, even when image noise or low contrast limits the visibility of the valve. [ABSTRACT FROM AUTHOR] - Published
- 2018
- Full Text
- View/download PDF
49. Development of a modeling pipeline for the prediction of hemodynamic outcome after virtual mitral valve repair using image-based CFD.
- Author
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Vellguth, Katharina, Brüning, Jan, Goubergrits, Leonid, Tautz, Lennart, Hennemuth, Anja, Kertzscher, Ulrich, Degener, Franziska, Kelm, Marcus, Sündermann, Simon, and Kuehne, Titus
- Abstract
Purpose: Severe mitral valve regurgitation can either be treated by a replacement or a repair of the valve. The latter is recommended due to lower perioperative mortality and better long-term survival. On the other hand, recurrence rates after mitral valve repair are high compared to those after replacements and the repair intervention can cause induced mitral valve stenosis. So far, there are no methods to predict the hemodynamic outcome of a chosen treatment or to compare different treatment options in advance. To overcome this, diastolic mitral valve hemodynamics are simulated using computational fluid dynamics after different virtual treatments of the valve.Methods: The left ventricular geometry of one patient was reconstructed using trans-esophageal echocardiography and computed tomography data. Pre-op hemodynamics are simulated using a referenced wall model to avoid expansive modeling of wall motion. Subsequently, the flow structures are compared to in vivo measurements. After manipulating the patient-specific geometry in order to mimic a restrictive mitral annuloplasty as well as a MitraClip intervention, hemodynamics results are calculated.Results: Good agreements exist between calculated pre-op hemodynamics and in vivo measurements. The virtual annuloplasty did not result in any remarkable change of hemodynamics. Neither the pressure drop nor the velocity field showed strong differences. In contrast, the virtual MitraClip intervention led to a complete change in blood flow structures as well as an elevated pressure drop across the valve.Conclusion: The presented approach allows fast simulation of the diastolic hemodynamic situation before and after treatment of a mitral valve insufficiency. However, this approach is limited to the early diastolic phase of the cardiac cycle and needs to be validated using a larger sample size. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
50. Sternal Anomalies in Asymptomatic Patients after Median Sternotomy and Potential Influencing Factors.
- Author
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Biefer, Hector Rodriguez Cetina, Sündermann, Simon H., Alkadhi, Hatem, Genoni, Michele, Maisano, Francesco, Emmert, Maximilian Y., and Plass, André
- Subjects
STERNUM surgery ,BODY mass index ,CARDIAC surgery ,AORTIC valve - Abstract
Background We aimed to assess asymptomatic patients who had open-heart surgery with median sternotomy for potential sternal anomalies (SA), their related patientspecific risk factors, and treatment options for the prevention of SA. Methods Multiplanar CT scans (CTs) from 131 asymptomatic consecutive patients were analyzed retrospectively. Of these, 83 underwent CABG (63.4%), and 48 had aortic valve (AV) procedures via median sternotomy. Sternal bone healing was analyzed for SA and their exact location. Results In total, 49 SA were identified in 42 (32.1%) patients; 65% SA were found in the manubrium (n = 32). Five hundred thirty-two wires were implanted (4.2 ± 0.5 wires/patient), out of which 96.1% (n = 511) were figure 8 wires. There was no difference between normal and abnormal sterna with regard to the number of wires used for sternal closure (4.2 ± 0.5 vs. 4.3 ± 0.6, p = ns). The distance between wire placement to the proximal edge of themanubrium in normal and abnormal sterna was comparable (11.2 ± 4.2 vs. 10.9 ± 4.8 mm, p = ns). Patients who underwent CABG had a significantly higher risk for SA (OR = 2.4, p ≤ 0.05, 95% CI [1.2-4.9]). The use of BIMA (OR = 4.4, p ≤ 0.05, 95% CI [1.1-17.9]) and body mass index (BMI) > 31 kg/m
2 (OR = 3.4, p ≤ 0.01, 95% CI [1.4-8.3]) significantly increased the risk of SA. Conclusion At least 30% of patients were at an increased risk for SA after receiving a median sternotomy. CABG, use of BIMA, and a BMI > 30 kg/m2 were potential risk factors for the development of SA and warrant close clinical follow-up. Sternal plate fixation, particularly in the manubrium, could be beneficial in such patients. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
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