Sex Differences in Clinical Outcomes After Transcatheter Aortic Valve Implantation ― Insights From a Nationwide Japanese Registry ―

BACKGROUND Sex differences in outcomes after transcatheter aortic valve implantation (TAVI) for aortic stenosis in Japan have not been fully investigated. METHODS AND RESULTS Using a nationwide registry, we evaluated sex differences in post-TAVI outcomes. In all, 36,353 patients (23,978 women, 12,375 men) were included. Women were older (84.9 vs. 83.5 years; P<0.001), had a smaller body surface area (BSA; 1.38 vs. 1.60 m2; P<0.001), and a lower prevalence of comorbidities than men. In-hospital mortality was comparable between women and men (1.2% vs. 1.3%, respectively; P=0.367). Women had higher rates of major red cell concentrate (RCC) transfusion (10.1% vs. 8.7%; P<0.001) and permanent pacemaker implantation (PPI; 7.1% vs. 5.9%; P<0.001). In multivariable analysis, BSA was inversely associated with in-hospital mortality (adjusted odds ratio [aOR] 0.84 per 0.1-m2increase; 95% confidence interval [CI] 0.77-0.91; P<0.001). Female sex was independently associated with lower risks of in-hospital mortality (aOR 0.60; 95% CI 0.45-0.81) and major RCC transfusion (aOR 0.79; 95% CI 0.71-0.89), but a higher risk of PPI (aOR 1.15; 95% CI 1.02-1.30). CONCLUSIONS In a Japanese TAVI registry, crude mortality was comparable between the sexes, but women had higher major RCC transfusion and PPI rates. After adjusting for BSA and available measured covariates, female sex was associated with lower in-hospital mortality. Combined sex and BSA assessment appears important for predicting post-TAVI outcomes.