Survival After Aortic Valve Replacement by Prosthesis Size vs the General Population

BACKGROUND Patients undergoing bioprosthetic aortic valve replacement (AVR) have worse long-term survival than the general population—we aim to evaluate how prosthesis size influences this relationship. METHODS From 2007-2018, 809 patients underwent isolated bioprosthetic AVR for aortic stenosis. Patients were stratified by sex and prosthesis size into sub-cohorts (male: size 23-25, size 27, size 29; female: size 21-23, size 25). Males with a size 23 or 25 prosthesis had comparable survival and were combined, as were females with a size 21 or 23 prosthesis. Males with a size ≤21(n=4) prosthesis and females with a size 19(n=2), 27(n=9) or 29(n=2) prosthesis were excluded for low sample sizes. Sub-cohort long-term survival was compared to the general population using age- and sex-matched lifetables. RESULTS Among males, median age was 67 (size 23-25), 63 (size 27), and 61 (size 29). Compared to the general population, long-term survival was significantly lower in the size 23-25 group with an estimated ten-year survival of 47.3% (95% confidence interval:39.7%,56.4%) vs 77.6%, but not significantly lower in the size 27 [65.7% (57.1%,75.6%) vs 80.3%] or size 29 groups [79.7% (71.3%,89.1%) vs 81.7%]. Among females, median age was 70 (size 21-23) and 64 (size 25). Long-term survival was significantly lower in the size 21-23 group with an estimated ten-year survival of 48.5% (40.0%,58.7%) vs 78.8%, and the size 25 group with an estimated ten-year survival of 60% (44.5%,81.0%) vs 85.5%. CONCLUSIONS Implantation of large bioprostheses (>size 25) was associated with survival approximating the sex- and age-matched general population.