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

Long-Term Outcomes of Bioprosthetic Valves in the Mitral Position: A Pooled Meta-Analysis of Reconstructed Time-to-Event Individual Patient Data

Bioprosthetic mitral valve replacement (bMVR) use is increasing; however, data regarding long-term durability are lacking. We sought to perform a reconstructed individual patient data meta-analysis from published Kaplan-Meier curves to ascertain survival, freedom from valve degeneration, and reoperation in studies published since 2010. We explored the effects of age and valve type (bovine pericardial or porcine valve) on outcomes. We searched MEDLINE, OVID, Embase, and Cochrane CENTRAL for studies reporting at least 3 years of follow-up after bMVR and published since 2010. The Risk Of Bias In Non-randomised Studies of Interventions (ROBINS-I) tool was used to assess methodologic quality. Kaplan-Meier curves were digitized to extract individual patient data and reconstructed estimates for overall survival, freedom from structural valve deterioration (SVD), and freedom from reoperation. A total of 20 studies (16,465 patients) were included. A total of 9 studies reported on porcine valves, 6 reported on bovine, and 7 did not specify the valve type. The overall survival after bMVR at 15 years was 40% (confidence interval 38% to 42%), freedom from reoperation at 15 years was 79% (confidence interval 76% to 82%), and freedom from SVD at 15 years was 64% (58% to 70%). Freedom from SVD was improved in the 70+ years age group (93% up to 25 years, hazard ratio 6.6 [2.5 to 17] for 18 to 59 vs >70 years, p <0.0001). There was no difference in valve durability or survival between bovine pericardial or porcine valves. In this meta-analysis of patients who underwent bMVR using newer generation valves, the inverse relation between age and SVD was reiterated in the 70+ years age group. The prosthesis type made no difference in the outcomes.

Long-term outcomes of bioprosthetic valves in the mitral position a systematic review of studies published over the last 20 years

OBJECTIVES

Although the use of bioprostheses for mitral valve replacement (bMVR) is on the rise, their long-term durability is not well described. Defining bMVR durability will be instrumental in setting the standard against which the performance of transcatheter mitral replacement is to be judged against. The authors of this systematic review aimed to identify, assess the quality and review the outcomes in studies reporting on long-term outcomes after bMVR published over the last 20 years.

METHODS

Medline, Embase and Cochrane CENTRAL were searched for studies that have reported outcomes beyond a minimum of 5 years of follow-up after bMVR. Cohort characteristics, definitions of structural valve deterioration (SVD) and outcomes were summarized. The risk of bias in included studies was assessed using the Cochrane QUIPS tool.

RESULTS

Twenty-one studies, including 15 833 patients, were identified. Sixty-four percent of all implants were porcine and the remaining bovine pericardial. Freedom from SVD at 10 years ranged from 58.9% to 100% and at 15 years from 58.3% to 93%. Freedom from reoperation ranged from 65% to 98.7% at 10 years and 78.5% to 91% at 15 years. Information on native valve pathology or dominant haemodynamic lesion was missing in 25% and 66% of studies, respectively. Reports of postoperative echocardiography were lacking, despite the heavy reliance on echocardiography for SVD diagnosis.

CONCLUSIONS

There is considerable variability in reporting bMVR long-term outcomes. As such, it is difficult to generate an unbiased, generalizable understanding of long- term outcomes after bMVR across the spectrum of mitral disease phenotypes.