Population study of sex-based outcomes after surgical aortic valve replacement

Background — Surgical aortic valve replacement (SAVR) is a key strategy for the treatment of aortic valve disease. However, studies have primarily involved males and it’s unclear as to whether these benefits can be extrapolated to females.

Methods — Clinical and administrative data sets for 12207 patients undergoing isolated SAVR in Ontario from 2008 – 2019 were linked. Males and females were balanced using inverse probability treatment weighting. Mortality, endocarditis, and major hemorrhagic and thrombotic events, as well as two composite outcomes; MACCE (major adverse cerebral and cardiovascular events) and PACE (patient-derived adverse cardiovascular and noncardiovascular events) and their component events, were compared in the weighted groups with a stratified log rank test.

Results — There were 7485 males and 4722 females in the study. Median follow-up was 5.2 years in both sexes. There was no difference in all-cause mortality between sexes (HR 0.949 [95% CI 0.851-1.059]). Male sex was associated with an increased risk of new-onset dialysis (HR 0.689 [95% CI 0.488, 0.974]).

Female sex was associated with a significantly increased risk of both new onset heart failure (HR 1.211 [95% CI 1.051-1.394] p=0.0081) and heart failure hospitalization (HR 1.200 [95% CI 1.036-1.390] p=0.015). There were no statistically significant differences in any of the other secondary outcomes between sexes.

Conclusions — This population health study demonstrated that there was no difference in survival between males and females undergoing SAVR. There were significant sex-related differences in the risk of heart failure and new-onset dialysis however these findings should be considered exploratory and require further study.