Effect of Elevated Body Mass Index on Outcomes of Transcatheter Aortic Valve Replacement for Severe Aortic Stenosis.

Background: The association of body mass index (BMI) and an "obesity paradox" with cardiovascular risk prediction is controversial. This study aimed to evaluate the impact of elevated BMI on the outcome of transcatheter aortic valve replacement (TAVR) for aortic stenosis.

Methods: This retrospective study included 1019 patients with a BMI of ≥18.5 kg/m2 divided into 3 groups: 1) normal BMI (18.5-24.9 kg/m2), 2) overweight (25-29.9 kg/m2), and 3) obese (≥30 kg/m2). Propensity score matching was used to compare normal BMI with overweight and normal BMI with obese.

Results: The median age of the cohort was 82 years, and 348 patients had a normal BMI, while 319 and 352 patients were overweight and obese, respectively. After 1 : 1 propensity score matching, 258 and 192 pairs between normal BMI and overweight, and normal BMI and obese patients, respectively, were analyzed. Both overweight and obese patients had higher post-transaortic mean gradients and lower indexed effective orifice areas compared to normal BMI patients. During a median follow-up of 25 (range: 0.1-72) months, all-cause mortality was similar between overweight or obese patients and patients with a normal BMI. However, in a subgroup analysis of patients with moderate/severe chronic lung disease, all-cause mortality was significantly higher in obese patients compared with normal BMI patients (hazard ratio = 3.49, 95% confidence interval, 1.21-10.0, P = .021).

Conclusions: In this study, the "obesity paradox" was not observed in patients undergoing TAVR; rather, in patients with significant lung disease, obesity may be associated with worse midterm outcomes after TAVR.