Bovine pericardial versus porcine stented replacement mitral valves: early hemodynamic performance and clinical results of a randomized comparison of the Perimount and the Mosaic valves

Long-Term Outcomes of Bovine versus Porcine Mitral Valve Replacement: A Multicenter Analysis

Introduction

Recent national guidelines recommending mitral valve replacement (MVR) for severe secondary mitral regurgitation have resulted in an increased utilization of mitral bioprosthesis. There is a paucity of data on how longitudinal clinical outcomes vary by prosthesis type. We examined long-term survival and risk of reoperation between patients having bovine vs. porcine MVR. Study Design. A retrospective analysis of MVR or MVR + coronary artery bypass graft (CABG) from 2001 to 2017 among seven hospitals reporting to a prospectively maintained clinical registry was conducted. The analytic cohort included 1,284 patients undergoing MVR (801 bovine and 483 porcine). Baseline comorbidities were balanced using 1 : 1 propensity score matching with 432 patients in each group. The primary end point was all-cause mortality. Secondary end points included in-hospital morbidity, 30-day mortality, length of stay, and risk of reoperation.

Results

In the overall cohort, patients receiving porcine valves were more likely to have diabetes (19% bovine vs. 29% porcine; p < 0.001), COPD (20% bovine vs. 27% porcine; p=0.008), dialysis or creatinine >2 mg/dL (4% bovine vs. 7% porcine; p=0.03), and coronary artery disease (65% bovine vs. 77% porcine; p < 0.001). There was no difference in stroke, acute kidney injury, mediastinitis, pneumonia, length of stay, in-hospital morbidity, or 30-day mortality. In the overall cohort, there was a difference in long-term survival (porcine HR 1.17 (95% CI: 1.00-1.37; p=050)). However, there was no difference in reoperation (porcine HR 0.56 (95% CI: 0.23-1.32; p=0.185)). In the propensity-matched cohort, patients were matched on all baseline characteristics. There was no difference in postoperative complications or in-hospital morbidity and 30-day mortality. After 1 : 1 propensity score matching, there was no difference in long-term survival (porcine HR 0.97 (95% CI: 0.81-1.17; p=0.756)) or risk of reoperation (porcine HR 0.54 (95% CI: 0.20-1.47; p=0.225)).

Conclusions

In this multicenter analysis of patients undergoing bioprosthetic MVR, there was no difference in perioperative complications and risk of reoperation of long-term survival after matching.

Bovine pericardial versus porcine bioprosthetic mitral valves: results from a Korean Nationwide Cohort Study

OBJECTIVES

Comparisons of long-term clinical outcomes of mitral valve replacement (MVR) between bovine pericardial and porcine bioprostheses are conflicting, with limited research in large-scale real-world clinical settings. This study examined clinical outcomes in MVR according to bioprosthesis type using a national administrative claims database.

METHODS

This study included adult patients undergoing bioprosthetic MVR between 2003 and 2018 using administrative health care data from the Korean National Health Insurance Service database. Propensity score matching with competing risk analysis was used to compare the clinical outcomes according to the type of bioprosthesis. The end points were death, cardiac death, and valve-related events, including the incidence of reoperation, endocarditis, systemic thromboembolism, and major bleeding.

RESULTS

A total of 3151 patients underwent bioprosthetic MVR with bovine pericardial (n = 1628, 51.7%) or porcine (n = 1523, 48.3%) bioprostheses. After matching, 1170 pairs were included in the final analysis. During follow-up (median 4.49 years, interquartile range 1.87 -8.75 years), death occurred in 1178 patients (6.8%/patient-year), comprising 730 (4.3%/patient-year) cardiac death. No significant differences were noted between the bovine and porcine groups in the cumulative incidences of death from any cause [adjusted hazard ratio (aHR), 1.00; 95% confidence interval (CI), 0.87-1.14], cardiac mortality (aHR, 0.96; 95% CI, 0.81-1.14), or reoperation (aHR, 1.01; 95% CI, 0.72-1.41).

CONCLUSIONS

This study on a nationwide comparison between bovine and porcine bioprostheses in MVR found no significant differences in clinical outcomes including mortality, and valve-related reoperation.

Comparison of a new bioprosthetic mitral valve to other commercially available devices under controlled conditions in a porcine model

Background/Aim

To evaluate three mitral bioprostheses (of comparable measured internal diameters) under controlled, stable, hemodynamic and surgical conditions by bench, echocardiographic, computerized tomography and autopsy comparisons pre‐ and postvalve implantation.

Methods

Fifteen similar‐sized Yorkshire pigs underwent preprocedural computerized tomography anatomic screening. Of these, 12 had consistent anatomic features and underwent implantation of a mitral bioprosthesis via thoracotomy on cardiopulmonary bypass (CPB). Four valves from each of three manufacturers were implanted in randomized fashion: 27‐mm Epic, 27‐mm Mosaic, and 25‐mm Mitris bioprostheses. After CPB, epicardial echocardiographic studies were performed to assess hemodynamic function and define any paravalvular leaks, followed by postoperative gated contrast computerized tomography. After euthanasia, animals underwent necropsy for anatomic evaluation.

Results

All 12 animals had successful valve implantation with no study deaths. Postoperative echocardiographic trans‐valve gradients varied among bioprosthesis manufacturers. The 25‐mm Mitris (5.1 ± 2.7)/(2.6 ± 1.3 torr) had the lowest peak/mean gradient and the 27‐mm Epic bioprosthesis had the highest (9.2 ± 3.7)/(4.6 ± 1.9 torr). Surgical valve opening area (SOA) varied with the 25‐mm Mitris having the largest SOA (2.4 ± 0.15 cm²) followed by the 27‐mm Mosaic (2.04 ± 0.23 cm²) and the 27‐mm Epic (1.8 ± 0.27 cm²) valve. Bench device orthogonal internal diameter measurements did not match manufacturer device size labeling: 25‐mm Mitris (23 × 23 mm), 27‐mm Mosaic (23 × 22 mm), 27‐mm Epic (21 × 21 mm).

Conclusions

Current advertisement/packaging of commercial surgical mitral valves is not uniform. This study demonstrates marked variations in hemodynamics, valve opening area and anatomic dimensions between similar sized mitral bioprostheses. These data suggest a critical need for standardization and close scientific evaluation of surgical mitral bioprostheses to ensure optimal clinical outcomes.

Surgical pericardial heart valves: 50 Years of evolution

Valve disease carries a huge burden globally and the number of heart valve procedures are projected to increase from the current 300 000 to 800 000 annually by 2050. Since its genesis 50 years ago, pericardial heart valve has moved leaps and bounds to ever more ingenious designs and manufacturing methods with parallel developments in cardiology and cardiovascular surgical treatments. This feat has only been possible through close collaboration of many scientific disciplines in the fields of engineering, material sciences, basic tissue biology, medicine and surgery. As the pace of change continues to accelerate, we ask the readers to go back with us in time to understand developments in design and function of pericardial heart valves. This descriptive review seeks to focus on the qualities of pericardial heart valves, the advantages, successes and failures encapsulating the evolution of surgically implanted pericardial heart valves over the past five decades. We present the data on comparison of the pericardial heart valves to porcine valves, discuss structural valve deterioration and the future of heart valve treatments.