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Objectives: Rapid deployment aortic valve replacement (AVR) has been developed to facilitate minimally invasive approaches for cardiac surgery and shorten procedural times. TRITON is a prospectively designed study to assess safety and efficacy of rapid deployment AVR with Edwards INTUITY valve system. This report presents the 5-year outcomes of the TRITON trial., Methods: A total of 295 patients with aortic valve stenosis were enrolled in the TRITON trial and 287 patients received the study valve. Procedural, early (≤30 days) and late (>30 days) outcomes were collected. Valve haemodynamic performance was evaluated at specified time points by an independent Echocardiography Core Laboratory and clinical events adjudicated by an independent Clinical Events Committee., Results: Mean age was 75.3 ± 6.7 years. A total of 158 patients underwent isolated AVR and 129 patients underwent AVR with concomitant procedures. The 5-year survival rates were 85.7 ± 3.4% and 75.2 ± 4.9% for isolated AVR and concomitant AVR, respectively. Overall, freedom from valve-related death at 5 years was 98.2 ± 0.8%. At 5 years, the valve effective orifice area was 1.6 ± 0.3 cm 2 , mean gradient was 10.5 ± 5.4 mmHg and peak gradient was 18.9 ± 9.3 mmHg., Conclusions: The 5-year outcomes of the TRITON trial demonstrate acceptable long-term safety and excellent haemodynamic performance of rapid deployment AVR with the Edwards INTUITY valve system., Clinicaltrials.gov: NCT01445171., (© The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Objectives: Bioprosthetic aortic heart valves are increasingly implanted in younger patients. Therefore, a strategy for potential valve failure should be developed before implanting the 'first valve'. The goal of this in vitro study was to provide insight into the effects of the design of a bioprosthesis on a valve-in-valve implanted Sapien XT valve., Methods: The hydrodynamic performance of a 23-mm Sapien XT valve implanted in Vascutek Aspire, Edwards Perimount, Medtronic Mosaic and St. Jude Medical Trifecta heart valves was investigated in a left heart simulator. In addition to the hydrodynamic results, the leaflet dynamics were analysed in high-speed video recordings of the tests., Results: All valve-in-valve combinations in this study fulfilled the minimum acceptance criteria defined by relevant approval standards (e.g. ISO 5840) but displayed significant differences in their performances. Small inner diameters of the bioprostheses were associated with increased mean pressure gradients, decreased effective orifice areas and geometric opening areas as well as with pin-wheeling and uneven leaflet motion. In addition, implantation in bioprostheses with internally mounted leaflets was associated with lower paravalvular leakage., Conclusions: The results of this study suggest that a surgical bioprosthesis with a large inner diameter and internally mounted leaflets improves the heamodynamics and potentially the durability of a valve-in-valve combination. These results should give the attending physicians critical information to consider when deciding on a bioprosthesis for younger patients., (© The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Objective: Minimal access aortic valve replacement is associated with favorable clinical outcomes; however, several meta-analyses have reported significantly longer crossclamp times compared with a full sternotomy. We examined the procedural and early safety outcomes after isolated rapid deployment aortic valve replacement by surgical approach in patients enrolled in the Surgical Treatment of Aortic Stenosis With a Next Generation Surgical Aortic Valve trial., Methods: The Surgical Treatment of Aortic Stenosis With a Next Generation Surgical Aortic Valve trial was a prospective, multicenter, single-arm study, with successful implants in 287 patients with aortic valve stenosis who underwent rapid deployment aortic valve replacement using the EDWARDS INTUITY Valve System (Edwards Lifesciences, Irvine, Calif). Patients were evaluated perioperatively for procedural times and technical success rates; at discharge, for hospital length of stay; and, at 30 days, for early adverse events., Results: A total of 158 patients underwent isolated aortic valve replacement through a full sternotomy (n = 71), upper hemisternotomy (n = 77), or right anterior thoracotomy (n = 10). Mean age at baseline was 75.7 ± 7.2 years. Mean aortic crossclamp and cardiopulmonary bypass times (minutes) were similar for full sternotomy and upper hemisternotomy, 43.5 ± 32.5/71.6 ± 41.8 and 43.1 ± 13.1/69.6 ± 19.1, respectively, and significantly longer for right anterior thoracotomy, 88.3 ± 18.6/122.2 ± 22.1 (P < .000). Early adverse event rates were similar, and in-hospital mortality rates were low regardless of surgical approach., Conclusions: These data suggest that isolated rapid deployment aortic valve replacement through an upper hemisternotomy can lead to shorter crossclamp times than has been reported historically in the literature. This may facilitate minimal access aortic valve replacement by eliminating the issue of prolonged crossclamp times. Further, low in-hospital mortality and new permanent pacemaker implant rates were observed regardless of surgical approach., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Valve-in-valve transcatheter aortic valve replacement (TAVR) is becoming a valuable option with promising clinical results in failed bioprosthetic heart valves. Sizing recommendations are based on size compatibility rather than on broad clinical data, in vitro measurements, or biomechanical evidence. The hemodynamic performance of transcatheter heart valves within degenerated surgical heart valves is unknown., Methods: We evaluated the in vitro hydrodynamic performance of two commercially available transcatheter heart valves (Medtronic CoreValve [Medtronic, Minneapolis, MN] and Edwards SAPIEN XT [Edwards Lifesciences, Irvine, CA]) in two different bioprosthetic aortic valves (Edwards Perimount [Edwards Lifesciences] and St. Jude Trifecta [St. Jude Medical, St. Paul, MN])., Results: Within the Edwards Perimount (23 mm) prosthesis, pressure gradients were higher for the SAPIEN XT compared with the CoreValve (11.2 ± 0.1 mm Hg versus 10.1 ± 0.1 mm Hg, p < 0.01), whereas effective orifice area (1.99 ± 0.01 cm(2) versus 1.80 ± 0.01 cm(2), p < 0.01) and total paravalvular leakage (9.0% ± 1.0% versus 5.4% ± 1.3%, p < 0.01) were increased when using the CoreValve. Similarly, measurements in the St. Jude Trifecta revealed higher transvalvular pressure gradients (13.0 ± 0.2 mm Hg versus 10.9 ± 0.3 mm Hg, p < 0.01) and lower effective orifice area for the SAPIEN XT compared with the CoreValve. However, total relative regurgitation was higher with SAPIEN XT as compared with the CoreValve in St. Jude Trifecta prostheses (11.2% ± 1.4% versus 8.3% ± 0.9%, p < 0.01)., Conclusions: Both transcatheter heart valve prostheses performed well in the described valve-in-valve settings. Hydrodynamic results were in line with the International Organization for Standardization standards for all configurations. The observed differences indicate a necessity for preclinical valve-in-valve tests in addition to clinical long-term data about longevity., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objectives: The number of implanted biological valves for treatment of valvular heart disease is growing and a percentage of these patients will eventually undergo a transcatheter valve-in-valve (ViV) procedure. Some of these patients will represent challenging cases. The aim of this study was to develop a feasible algorithm to plan and in vitro simulate a new interventional procedure to improve patient outcome., Methods: In addition to standard diagnostic routine, our algorithm includes 3D printing of the annulus, hydrodynamic measurements and high-speed analysis of leaflet kinematics after simulation of the procedure in different prosthesis positions as well as X-ray imaging of the most suitable valve position to create a 'blueprint' for the patient procedure., Results: This algorithm was developed for a patient with a degenerated Perceval aortic sutureless prosthesis requiring a ViV procedure. Different ViV procedures were assessed in the algorithm and based on these results the best option for the patient was chosen. The actual procedure went exactly as planned with help of this algorithm., Conclusions: Here we have developed a new technically feasible algorithm simulating important aspects of a novel interventional procedure prior to the actual procedure. This algorithm can be applied to virtually all patients requiring a novel interventional procedure to help identify risks and find optimal parameters for prosthesis selection and placement in order to maximize safety for the patient., (© The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Objective: Superior aortic valve hemodynamic performance can accelerate left ventricular mass regression and enhance survival and functional status after surgical aortic valve replacement. This can be achieved by rapid deployment aortic valve replacement using a subannular balloon-expandable stent frame, which functionally widens and reshapes the left ventricular outflow tract, to ensure a larger effective orifice area compared with conventional surgical valves. We report the intermediate-term follow-up data from a large series of patients enrolled in the Surgical Treatment of Aortic Stenosis With a Next Generation Surgical Aortic Valve (TRITON) trial., Methods: In a prospective, multicenter (6 European hospitals), single-arm study, 287 patients with aortic stenosis underwent rapid deployment aortic valve replacement using a stented trileaflet bovine pericardial bioprosthesis. Core laboratory echocardiography was performed at baseline, discharge, and 3 months, 1 year, and 3 years after rapid deployment aortic valve replacement., Results: The mean patient age was 75.7 ± 6.7 years (range, 45-93; 49.1% women). The mean aortic valve gradient significantly decreased from discharge to 3 years of follow-up. The mean effective orifice area remained stable from discharge to 3 years. At 1 year, the left ventricular mass index had decreased by 14% (P < .0001) and at 3 years by 16% (P < .0001) compared with at discharge. The prevalence of severe patient-prosthesis mismatch was 3% at discharge and remained stable during the follow-up period., Conclusions: In a large series of elderly patients with symptomatic severe aortic stenosis, rapid deployment aortic valve replacement using a subannular balloon-expandable stent frame demonstrated excellent hemodynamic performance and significant left ventricular mass regression. With continued follow-up, future studies will establish whether these favorable structural changes correlate with improvement in long-term survival and functional status., (Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Background/objectives: To evaluate the predictive value of CT-derived measurements of the aortic annulus for prosthesis sizing in transcatheter aortic valve implantation (TAVI) and to calculate optimal cutoff values for the selection of various prosthesis sizes., Methods: The local IRB waived approval for this single-center retrospective analysis. Of 441 consecutive TAVI-patients, 90 were excluded (death within 30 days: 13; more than mild aortic regurgitation: 10; other reasons: 67). In the remaining 351 patients, the CoreValve (Medtronic) and the Edwards Sapien XT valve (Edwards Lifesciences) were implanted in 235 and 116 patients. Optimal prosthesis size was determined during TAVI by inflation of a balloon catheter at the aortic annulus. All patients had undergone CT-angiography of the heart or body trunk prior to TAVI. Using these datasets, the diameter of the long and short axis as well as the circumference and the area of the aortic annulus were measured. Multi-Class Receiver-Operator-Curve analyses were used to determine the predictive value of all variables and to define optimal cutoff-values., Results: Differences between patients who underwent implantation of the small, medium or large prosthesis were significant for all except the large vs. medium CoreValve (all p's<0.05). Furthermore, mean diameter, annulus area and circumference had equally high predictive value for prosthesis size for both manufacturers (multi-class AUC's: 0.80, 0.88, 0.91, 0.88, 0.88, 0.89). Using the calculated optimal cutoff-values, prosthesis size is predicted correctly in 85% of cases., Conclusion: CT-based aortic root measurements permit excellent prediction of the prosthesis size considered optimal during TAVI.

Objectives: Aortic homografts are an alternative to mechanical or biological valve prostheses. Homografts are generally not transplanted ABO-compatible while this policy is still under debate. The purpose of this study was to investigate whether ABO compatibility impacts on long-term outcomes or not., Methods: Between 1992 and 2009, 363 adult patients with a mean age of 52 years received homografts in aortic position. Donor and acceptor blood groups could be obtained for 335 patients. Sixty-three percent received blood group-compatible (n = 212) (Group iso) and 37% non-blood group-compatible allografts (n = 123) (Group non-iso)., Results: The overall event-free survival (freedom from death or reoperation) was 55.5% (n = 186). In the iso group, the event-free survival was 84.1% at 5 years and 63.3% at 10 years. In the non-iso group, the event-free survival was 79.4% at 5 years and 51.8% at 10 years. 28.5% of patients (n = 35) with ABO-incompatible and 25.5% (n = 54) with ABO-compatible grafts required reoperation. The mean time to reoperation in the iso group was 97.3 vs 90 months in the non-iso group., Conclusions: In 17 years of research, we have not yet found a statistical significant difference in blood group incompatibility regarding overall event-free survival. In our opinion, there is no need to use ABO-compatible homografts for aortic valve replacement in adults. Histological and immunohistochemical assays are mandatory to confirm our results.

The aim of the study was to compare the behavior of seeded cells on synthetic and natural aortic valve scaffolds during a low-flow conditioning period. Polyurethane (group A) and aortic homograft valves (group B) were consecutively seeded with human fibroblasts (FB), and endothelial cells (EC) using a rotating seeding device. Each seeding procedure was followed by an exposure to low pulsatile flow in a dynamic bioreactor for 5 days. For further analysis, samples were taken before and after conditioning. Scanning electron microscopy showed confluent cell layers in both groups. Immunohistochemical analysis showed the presence of EC and FB before and after conditioning as well as the establishment of an extracellular matrix (ECM) during conditioning. A higher expression of ECM was observed on the scaffolds' inner surface. Real-time polymerase chain reaction showed higher inflammatory response during the conditioning of homografts. Endothelialization caused a decrease in inflammatory gene expression. The efficient colonization, the establishment of an ECM, and the comparable inflammatory cell reaction to the scaffolds in both groups proved the biocompatibility of the synthetic scaffold. The newly developed bioreactor permits conditioning and cell adaption to shear stress. Therefore, polyurethane valve scaffolds may offer a new option for aortic valve replacement.

Background: Tissue engineering represents a promising new method for treating heart valve diseases. The aim of this study was evaluate the importance of conditioning procedures of tissue engineered polyurethane heart valve prostheses by the comparison of static and dynamic cultivation methods., Methods: Human vascular endothelial cells (ECs) and fibroblasts (FBs) were obtained from saphenous vein segments. Polyurethane scaffolds (n = 10) were primarily seeded with FBs and subsequently with ECs, followed by different cultivation methods of cell layers (A: static, B: dynamic). Group A was statically cultivated for 6 days. Group B was exposed to low flow conditions (t₁=3 days at 750 ml/min, t₂=2 days at 1100 ml/min) in a newly developed conditioning bioreactor. Samples were taken after static and dynamic cultivation and were analyzed by scanning electron microscopy (SEM), immunohistochemistry (IHC), and real time polymerase chain reaction (RT-PCR)., Results: SEM results showed a high density of adherent cells on the surface valves from both groups. However, better cell distribution and cell behavior was detected in Group B. IHC staining against CD31 and TE-7 revealed a positive reaction in both groups. Higher expression of extracellular matrix (ICAM, Collagen IV) was observed in Group B. RT- PCR demonstrated a higher expression of inflammatory Cytokines in Group B., Conclusion: While conventional cultivation method can be used for the development of tissue engineered heart valves. Better results can be obtained by performing a conditioning step that may improve the tolerance of cells to shear stress. The novel pulsatile bioreactor offers an adequate tool for in vitro improvement of mechanical properties of tissue engineered cardiovascular prostheses.

Objective: Pressure recovery results in Doppler gradients greater than catheter gradients and is well established in association with bileaflet mechanical aortic valves. Because pressure recovery is influenced by orifice geometry, it might manifest differently with various valve prostheses. If true, then the reliability of Doppler echocardiography for the estimation of aortic valve gradients might be different with different prostheses. The purpose of the present study was to test, in an in vitro setting, the degree to which pressure recovery results in Doppler overestimation of gradients for three commonly used aortic valve prostheses., Methods: Carpentier Edwards Perimount, Medtronic Mosaic, and St. Jude Medical bileaflet prostheses were tested under various flow conditions in a pulsatile mock flow loop with a normal aorta size. Mean pressure gradient was assessed with transducers 1 cm and 10 cm distal to the valve and with Doppler echocardiography. Pressure recovery was defined as the difference between the Doppler gradient and a 10-cm gradient. The percentage of the maximum pressure gradient composed of pressure recovery and the percentage of pressure recovery complete 1 cm distal to the valve were calculated., Results: There was substantial pressure recovery for all valves in all flow states. Pressure recovery was responsible for 50% or more of the Doppler gradients for almost all conditions and was more than 70% complete within 1 cm for almost all conditions. Multivariate analysis found that flow and valve area (but not valve type) were predictors of pressure recovery; that flow was the major predictor of the percentage of Doppler gradient composed of pressure recovery (with minor contributions from the aorta size and prosthesis type); and that valve type and aorta size were the major predictors of the percentage of pressure recovery complete at 1 cm., Conclusions: In an in vitro model with a normal aorta size, substantial pressure recovery occurred with all three aortic valve prostheses. Although statistically significant differences were found between valve types in the percentage of pressure recovery and percentage of pressure recovery complete at 1 cm, the differences were small and clinically unimportant. Clinically, among patients with an ascending aorta diameter less than 3.0 cm, Doppler echocardiography likely substantially overestimates aortic valve mean gradient, regardless of prosthesis type., (Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

In this study, we show the use of three-dimensional printing models for preoperative planning of transcatheter valve replacement in a patient with an extreme porcelain aorta. A 70-year-old man with severe aortic stenosis and a porcelain aorta was referred to our center for transcatheter aortic valve replacement. Unfortunately, the patient died after the procedure because of a potential ischemic event. Therefore, we decided to fabricate three-dimensional models to evaluate the potential effects of these constructs for previous surgical planning and simulation of the transcatheter valve replacement., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objective: Valvuloplasty of the aortic valve is currently used in selected patients for severe calcified aortic valve disease, but clinical effectiveness is low and complication rate remains high. In this study, the total particle load after valvuloplasty and the embolization risk of calcific debris into the coronary arteries was analyzed in an in vitro model., Methods: Three highly calcified human aortic leaflets have been sutured into a porcine annulus (N = 9). Both coronary arteries were separated and each was anastomized to a silicon line, which was drained off into a measuring beaker. Then valvuloplasty was performed (Thyshak II, 20 mm, 1.5 atm). After removal of the balloon, 100ml of sodium chloride solution irrigated the ascending aorta. After passing through the separated coronary arteries, the solution was filtered (filter size 0.45 μm), dried, and the total amount of particles was analyzed microscopically., Results: Nine experiments were analyzed. After valvuloplasty, all hearts showed a median of 18 particles larger than 1mm in the coronary arteries (range 0-307). The amount of particles smaller than 1mm was 6574 (median, range 2207-14200). In five cases, coronary arteries were completely occluded by bulky particles., Conclusion: This study demonstrated a large amount of calcific particles after valvuloplasty with a consequently high risk for coronary embolic events in case of highly calcified aortic valves. In times of valvuloplasty rediscovering as part of transcatheter valve implantation, the risk of embolization should be taken into consideration and filtering techniques have to be developed., (Copyright © 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.)

Objective: To evaluate the modular sutureless Arbor Trilogy Aortic Valve System (Arbor Surgical Technologies, Irvine, Calif), designed for minimally invasive aortic valve replacement., Methods: In a prospective multicenter study, 32 patients with severe aortic valve stenosis underwent aortic valve replacement with the Trilogy valve between 2006 and 2008. Concomitant coronary artery bypass grafting was performed in 6 patients. Transthoracic echocardiography was performed at baseline, at discharge, at 4 to 6 months, at 11 to 14 months, and annually thereafter., Results: Valve implantation was successful in 30 patients. The procedure was converted to conventional aortic valve replacement in 2 patients. Mean bypass time was 111 ± 42 minutes, and crossclamp time was 70 ± 23 minutes. Valve implantation took 21 ± 7 minutes. The transvalvular gradients at discharge were 10 ± 3 mm Hg (mean) and 20 ± 7 mm Hg (peak), and the effective orifice area was 1.9 ± 0.4 cm(2). At 2-year follow-up, gradients were 7 ± 3 mm Hg (mean) and 14 ± 4 mm Hg (peak), and the effective orifice area was 1.9 ± 0.3 cm(2). There was no intraoperative mortality: Two patients died of causes unrelated to the valve during follow-up. One redo aortic valve replacement was performed at 22 months for prosthetic valve endocarditis., Conclusions: Sutureless aortic valve replacement is feasible and safe with the Trilogy System. After an initial learning curve, the modular valve design allows a more rapid and simple implantation compared with conventional stented tissue valves. The simplicity may also facilitate a greater adoption of minimally invasive aortic valve replacement by a broader spectrum of surgeons., (Copyright © 2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Introduction: Paravalvular fistulas may complicate the clinical course after heart valve surgery. Medical treatment may be ineffective, repeated surgical revisions may be associated with increased morbidity and mortality., Case Report: After valve sparing surgery in bicuspid aortic valve, a significant aorto-left atrial fistula was diagnosed in a 72-year-old patient causing heart failure and catecholamine-dependency. Due to the critical hemodynamic state, percutaneous closure was performed with an AGA Amplatzer duct occluder. Secondary to this closure, a second fistula between the aortic root and the right atrium appeared which was closed during the same procedure implanting a second duct occluder beneath the first device., Conclusion: Percutaneous closure of paravalvular fistulas is feasible and a safe method for the treatment of significant shunts after valve surgery. Even in multiple fistulas, the implantation of small devices allows for a focussed interventional closure of such leaks. This procedure should be considered for such defects as it represents a safe method for the causative treatment in paravalvular lesions after valve surgery especially in patients with critical hemodynamic conditions.

Iatrogenic nerve lesions affecting the long thoracic nerve are very rare after a median sternotomy. Here we report on a patient who developed clinical signs of a so-called "winged scapula" after an uneventful aortic valve replacement for infective endocarditis.

Aim: Despite continuous development of anticalcification treatment for bioprosthetic valves, calcification remains one major cause of structural failure. The aim of this study is to investigate changes in hemodynamic performance and leaflet kinematics in progressively calcified pericardial and porcine aortic valve prostheses., Methods: Five pericardial (Edwards Perimount Magna) and 5 porcine (Medtronic Mosaic Ultra) aortic valve prostheses (Ø23 mm) were exposed to a high concentration Calcium-phosphate fluid in an in vitro pulse duplicator (300 cycles/minute) for 6 weeks. The prostheses were removed weekly and tested in an artificial circulation system (70 beats/min, Cardiac Output 5 l/min). All prostheses underwent X-ray, computed tomography (CT)-Scan and photographic examination for evaluation of progressive calcification. Leaflet kinematics were visualized with a high-speed camera., Results: Pericardial valves demonstrated faster degeneration with significantly larger radiographic areas of leaflet calcification (16.5+/-4.3% versus 5.6%+/-2.0%) and also significantly higher Ca-uptake (170+/-71 microg/mg versus 103+/-49 microg/mg) after 6 weeks. Despite degeneration systolic function remained superior for pericardial valves (mean effective orifice area [EOA] 1.52+/-0.05 versus 1.28+/-0.11 cm2, P<0.01), but leaflet kinematics showed longer closing times (135+/-11 msec versus 85+/-9 msec after 6 weeks) accompanied by higher regurgitant flow (7.8+/-1.12 mL versus 1.2+/-0.28 mL, P<0.001)., Conclusion: In vitro pericardial valves calcified faster and more severe than porcine valves leading to impaired diastolic function with prolongation of closing times and higher closing volume. Systolic function remained almost undisturbed by the calcification process. As a consequence in clinical settings, follow-up examinations for structural valve deterioration in porcine valves should focus on systolic performance, in pericardial valves on diastolic function.

Objective: Despite continuous development of anticalcification treatment for biological valve prostheses, calcification remains one major cause of structural failure. The following study investigates hemodynamics and changes in opening and closing kinematics in progressively calcified porcine and pericardial valves in a simulated exercise situation., Materials and Methods: Five pericardial (Edwards Perimount Magna) and five porcine (Medtronic Mosaic Ultra) aortic valve bioprostheses (23 mm) were investigated in an artificial circulation system (150 beats/min, cardiac output 8l/min). Leaflet kinematics were visualized with a high-speed camera (3000 frames/s). Valves were exposed to a calcifying solution for 6 weeks. Repeated testing was performed every week. All prostheses underwent X-ray and photographic examination including measurement of calcium content for evaluation of progressive calcification., Results: In the exercise situation pericardial valves demonstrated lower pressure gradients initially compared to the porcine valves (8.5+/-1.4 vs 11+/-1.6 mmHg), but significantly higher closing volume (5.3+/-1.2 ml vs 1.2+/-0.2 ml of stroke volume) leading to an equal total energy. Neither valve type demonstrated a significant increase in gradient or closing volume compared to the normal output situation. Opening and closing times were longer for pericardial valves after 6 weeks (opening time 42+/-10 ms vs 28+/-10 ms, closing time 84+/-12 vs 52+/-10 ms after 6 weeks). Pericardial valves calcified faster and more severely leading to an increase in gradients and closure volume., Conclusions: In the exercise situation pericardial valves demonstrated superior systolic function compared to porcine valves. Therefore pericardial valves have some advantage in active patients due to the lower gradients. Total energy loss remained constant during progressive calcification for both valves. Leaflet opening and closing is faster in porcine valves; clinical impact of these findings is not known. Diastolic performance is also important and should always be tested also in vivo.

Background and Aim of the Study: Heart failure is common following aortic valve replacement, and optimal prosthesis function is crucial in this critical clinical setting. The study aim was to investigate the hemodynamic performance and leaflet kinematics of fresh and calcified biological aortic valves in a simulated low stroke volume situation., Methods: Edwards Perimount Magna (PM) and Medtronic Mosaic Ultra (MU) valves were investigated in an artificial circulation system (130 beats/min, stroke volume 19 ml), and the results compared to normal output (70 beats/min, stroke volume 70 ml). Leaflet kinematics were visualized using a high-speed camera. All valves were exposed to a calcifying solution for six weeks., Results: In the low- and normal-output situation, the PM valve initially demonstrated lower pressure gradients compared to the MU valve (low output 2.4 +/- 0.16 versus 3.4 +/- 0.19 mmHg), but showed a significantly higher closing volume (up to 19% of stroke volume) leading to an increased total energy loss. Regurgitation for the PM valve was explained by progressively longer opening and closing times. The PM valve calcified faster and more severely, leading to increasing gradients and closure volume., Conclusion: In the low stroke volume situation pericardial valves demonstrated superior systolic performance, but inferior diastolic performance, leading to a higher total energy loss compared to porcine valves. This finding may have clinical relevance in heart-failure patients.

Objective: In aortic valve regurgitation and aortic dilatation, preservation of the aortic valve is possible by means of root remodeling (Yacoub procedure) or valve reimplantation (David procedure). In vivo studies suggest that reimplantation might substantially influence aortic valve-motion characteristics. Evaluation of aortic valve movement in vivo, however, is technically limited and is difficult to standardize. We evaluated the aortic valve-motion pattern echocardiographically in vitro after reimplantation and remodeling., Methods: By using aortic roots of house pigs (aortoventricular diameter, 22 mm) a Yacoub procedure (22-mm graft; group Y, n = 5) or a David I procedure (24-mm graft; group D, n = 5) was performed. Roots after supracommissural replacement (22-mm graft; group C, n = 5) served as control valves. In an electrohydraulic, computer-controlled pulse duplicator the valves were tested at flows of 2, 4, 7, and 9 L/min. Echocardiographically assessed parameters were rapid valve-opening velocity, slow valve-closing velocity, rapid valve-closing velocity, rapid valve-opening time, rapid valve-closing time, ejection time, maximum valve opening, slow valve-closing displacement, and maximum flow velocity., Results: Mean rapid valve-opening velocity and mean rapid valve-closing velocity at a cardiac output of 2 to 9 L/min were fastest in group D (rapid valve-opening velocity: 69 +/- 10 cm/s [group D] vs 39 +/- 4 cm/s [group Y] vs 42 +/- 4 cm/s [group C], P = .0041; rapid valve-closing velocity: 22 +/- 2 cm/s [group D] vs 16 +/- 2 cm/s [group Y] vs 17 +/- 1 cm/s [group C], P = .0272), and slow valve-closing velocity was slowest in group D (0.2 +/- 0.1 cm/s [group D] vs 1.0 +/- 0.3 cm/s [group Y] vs 0.6 +/- 0.1 cm/s [group C], P = .0063). With increasing cardiac output, the difference in rapid valve-opening velocity between the groups increased, the difference in slow valve-closing velocity remained unchanged, and the difference in rapid valve-closing velocity decreased., Conclusions: In this standardized experimental setting remodeling of the aortic valve provides significantly smoother valve movements. This might contribute to preservation of a better valve performance during long-term follow-up.

Background and Aim of the Study: Valve-preserving aortic replacement has become an accepted option for patients with aortic valve regurgitation and aortic dilatation. The relative role of root remodeling versus valve reimplantation inside a vascular graft has been discussed, albeit controversially. In the present study, an in-vitro model was used to investigate the aortic valve hemodynamics of root remodeling and valve reimplantation; roots with supracommissural aortic replacement served as controls., Methods: Aortic roots with aortoventricular diameter 21 mm were obtained from pigs. Root remodeling was performed using a 22-mm graft (group I, n = 6), or valve reimplantation with a 24-mm graft (group II, n = 7). Control roots were treated by supracommissural aortic replacement (22-mm graft; group III, n = 7). Using an electrohydraulic, computer-controlled pulse duplicator, the valves were tested at flows of 2, 4, 5, 7, and 9 I/min at a heart rate of 70 /min and a mean arterial pressure of 100 mmHg. Parameters assessed included: mean pressure gradient, effective orifice area, valve closure and regurgitant volume, and energy loss due to ejection, valve closure and regurgitation. Data were compared using ANOVA., Results: There were no differences between the three groups in terms of regurgitant volume, energy loss due to valve regurgitation, or valve closure. The aortic valve orifice area was largest and systolic gradient lowest in group I at all flow rates (p < 0.001). Ejection energy loss was lowest in group I at all flow rates (9 l/min: group I, 128 +/- 21 mJ; group II, 399 +/- 46 mJ; group III, 312 +/- 27 mJ; p < 0.001). Valve closure volumes were similar in groups I and III, but significantly lower in group II at all flow rates (p = 0.047)., Conclusion: In this standardized experimental setting, root remodeling--but not valve reimplantation--resulted in physiologic hemodynamic performance of the aortic valve with regard to orifice area, pressure gradient, and systolic energy loss.

Background: Pressure recovery is not taken into account when calculating trans-prosthetic gradients after mechanical valve replacement using Doppler echocardiography. This may lead to underestimation of valvular performance., Methods: Simultaneous measurement of Doppler and direct trans-prosthetic gradients was performed in a circulatory mock loop simulator with physiologic parameters at different heart rates and cardiac outputs for small-sized aortic Omnicarbon tilting disc valves (19 - 21 mm)., Results: In all adjustments the Doppler gradient significantly overestimated the net transvalvular gradient. The amount of pressure recovery averaged 59.3 %., Conclusions: Doppler echocardiography does not allow for pressure recovery, which is a significant phenomenon in the hemodynamic function of the Omnicarbon tilting disc valve. Valve performance is much better than expected from Doppler gradients.

Objective: This study was undertaken to determine whether the presence of vortices immediately above a prosthetic aortic valve could negatively influence the in vitro hydrodynamic performances of a biologic or mechanical valve implanted in a new Dacron polyester fabric conduit that incorporates sculpted sinuses of Valsalva., Methods: With a computer-controlled pulse duplicator, the in vitro performance (pressure differences, closure and leakage volumes, and energy losses) of a 25-mm mechanical or biologic prosthesis implanted in a standard Dacron straight conduit or in the new Dacron graft with a sculpted sinus were analyzed and compared., Results: The mechanical and biologic prostheses at 7 L/min cardiac output showed pressure drops across the valve of 8.72 mm Hg and 13.45 mm Hg, respectively, when inserted in the new Valsalva-style graft and of 7.97 mm Hg and 12.94 mm Hg, respectively, when inserted in the standard graft. The closure and leakage volumes for mechanical valves were higher than those for biologic valves; however, the presence or absence of sinuses did not result in significant differences in closure and leakage volumes. The maximal total energy losses were 5.89% and 9.49% for mechanical and biologic valves, respectively. No differences were evident between the two different Dacron grafts for each prosthetic heart valve., Conclusion: The normal opening and closing behavior of a prosthetic aortic valve was not altered or modified by a different root shape above the heart valve. The presence of vortices inside the pseudosinuses of Valsalva did not influence the hydrodynamic properties of the biologic and mechanical valves tested.

The hydrodynamic performance of four currently used bileaflet heart valve prostheses (St. Jude Medical, CarboMedics, modified Edwards-Duromedics, and Sorin-Bicarbon) with a nominal tissue anulus diameter of 27 mm were measured in the aortic position. All experiments were performed in nonpulsatile flow and in an electrohydraulic, computer-controlled pulse duplicator simulating the left side of the human circulatory system. Testing conditions were set at cardiac outputs of 3.0, 4.5, 6.5, and 8.0 L/min at a constant heart rate of 70 beats/min. The Sorin-Bicarbon valve had the lowest pressure difference with regard to nonpulsatile (mean 5.4 mm Hg at 30 L/min) and pulsatile (mean 2.2 mm Hg at 8 L/min) flow, followed by the St. Jude Medical, CarboMedics, and modified Edwards-Duromedics valves. The leakage volumes under static and pulsatile flow conditions were lowest for the modified Edwards-Duromedics and Sorin-Bicarbon valves. The energy loss in pulsatile flow was lowest for the Sorin-Bicarbon valve, mainly because its systolic, closure, and leakage energy losses were low. Systolic sequential velocity profiles showed the most even flow distribution pattern for the St. Jude Medical and Sorin-Bicarbon valves. These findings correspond with lower overall Reynolds shear stress levels for the St. Jude Medical and the Sorin-Bicarbon valves than for the modified Edwards-Duromedics and CarboMedics valves.

We developed a new fabrication technique for 3-dimensional scaffolds for tissue engineering of human heart valve tissue. A human aortic homograft was scanned with an X-ray computer tomograph. The data derived from the X-ray computed tomogram were processed by a computer-aided design program to reconstruct a human heart valve 3-dimensionally. Based on this stereolithographic model, a silicone valve model resembling a human aortic valve was generated. By taking advantage of the thermoplastic properties of polyglycolic acid as scaffold material, we molded a 3-dimensional scaffold for tissue engineering of human heart valves. The valve scaffold showed a deviation of only ±3–4% in height, length and inner diameter compared with the homograft. The newly developed technique allows fabricating custom-made, patient-specific polymeric cardiovascular scaffolds for tissue engineering without requiring any suture materials. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]