Impact of body mass index on outcomes in patients undergoing transfemoral transcatheter aortic valve implantation

Objective: This study sought to investigate the effect of body mass index on outcomes in patients with severe aortic valve stenosis undergoing transcatheter aortic valve implantation.

Methods: A total of 12,381 patients undergoing transfemoral transcatheter aortic valve implantation were divided into body mass index categories: underweight (<18.5 kg/m²), normal weight (18.5-24.9 kg/m²), overweight (25.0-29.9 kg/m²), and obesity (>30 kg/m²). Primary endpoints were differences in 30-day and 1-year all-cause mortality. Secondary endpoints included all other clinical endpoints such as stroke. Univariate and multivariate odds ratios were calculated using logistic and cox regression analyses.

Results: Two percent (n = 205) of patients were underweight, 29% (n = 3564) were normal weight, 44% (n = 5460) were overweight, and 25% (n = 3152) were obese. Thirty-day mortality was lower in overweight (5.3%, odds ratio, 0.73; 95% confidence interval, 0.61-0.88; P = .001) and obese patients (5.2%, odds ratio, 0.74; 95% confidence interval, 0.60-0.92; P = .006), but higher in underweight (9.8%, odds ratio, 1.51; 95% confidence interval, 0.92-2.47; P = .010) as compared to normal weight patients (6.9%). After multivariate adjustment, 30-day mortality was not significantly different across body mass index categories. However, 1-year mortality was higher in underweight patients (hazard ratio, 1.52; 95% confidence interval, 1.10-2.09; P = .011). Stroke rates were comparable between body mass index groups.

Conclusions: For overweight and obese patients with severe aortic valve stenosis undergoing transcatheter aortic valve implantation, there was no 30-day difference in mortality compared with patients with normal weight. However, underweight patients showed higher rates of 1-year mortality after transcatheter aortic valve implantation.