(P269) TWENTY-YEAR OUTCOMES FOLLOWING PORCINE VERSUS PERICARDIAL AORTIC VALVE REPLACEMENT

Background: Bioprosthetic valves have become the most commonly used prostheses for surgical aortic valve replacement (SAVR), with stented porcine and bovine pericardial valves being the most frequently implanted types. Despite their widespread use, data comparing long-term outcomes between these two types of bioprostheses are scarce. This study aims to examine the twenty-year outcomes of patients who underwent isolated SAVR using either porcine or bovine pericardial bioprosthetic valves.

METHODS AND RESULTS: All patients who underwent isolated first-time AVR using either a stented porcine (Hancock II) or bovine pericardial (Perimount / Magna-Ease) bioprosthesis from 1990-2014 were included in this observational, single-center study. Patient demographics, surgical details, and in-hospital outcomes were prospectively collected in our institutional database. Cases were linked to provincial administrative databases at an independent, non-profit research institute whose legal status allows it to collect and analyze healthcare and demographic data. The primary outcome of interest was all-cause mortality. The secondary outcome was aortic valve reoperation (surgical or transcatheter). Kaplan-Meier curves were generated for long-term survival and cumulative incidence functions for aortic valve reoperation. In order to account for differences in baseline characteristics between groups, inverse probability treatment weighting using propensity scores was used.

A total of 1,306 patients were included (porcine: 751 [58%]; pericardial: 555 [42%]). Mean age was 68±12 years, and 569 (44%) were female. Propensity score weighting resulted in comparable cohorts with similar baseline characteristics. At 20 years, survival was 26% in the porcine group and 27% in the pericardial group (HR [95% CI]: 0.96 [0.81–1.14]; p=0.64) (Figure 1A). At 20 years, aortic valve reintervention had occurred in 19% of patients in the porcine group versus 26% in the pericardial group (HR [95% CI]: 1.68 [1.21–2.33]; p=0.002) (Figure 1B). In pre-specified subgroup analyses, rates of aortic valve reintervention were found to be higher in the pericardial group for both patients ≤65 years (HR: 1.66 [1.15–2.41]; p=0.007) and >65 years (HR: 2.21 [1.12–4.37]; p=0.022) (Figure 2A). Rates of aortic valve reintervention were higher in the pericardial group when the implanted prosthesis size was ≥25 mm or larger (HR: 2.44 [1.58–3.76]; p< 0.0001) but not when the implanted prosthesis size was < 25 mm (HR: 1.28 [0.69–2.36]; p=0.44).

Conclusion: Stented porcine and pericardial bioprostheses show equivalent long-term survival following SAVR, but porcine valves have lower reintervention rates, especially in larger sizes. Porcine valves may be preferable in scenarios where a large prosthesis can be implanted, regardless of patient age.