Obesity Paradox in Transcatheter Aortic Valve Replacement

Obesity paradox in cardiovascular risk prediction has gained increasing attention in recent years. We aimed to investigate the impact of BMI on mortality following transcatheter aortic valve replacement (TAVR).

We performed a multi-center retrospective analysis of patients with severe aortic stenosis undergoing TAVR. Patients were categorized into: Underweight (BMI < 18.5), normal weight (18.5 ≤ BMI < 25), overweight (25 ≤ BMI < 30) and obese (BMI ≥ 30). Multivariate cox-proportional hazard model was used to compare all-cause mortality.

Total of 6688 patients included (175 underweight, 2252 normal weight, 2368 overweight and 1893 with obesity). Mean age of patients was 81 ± 8 years with 55% males. Patients with obesity had higher prevalence of comorbidities but a lower overall STS score. Mortality at 30-days post-TAVR was lower in the obese population compared to underweight, normal weight, and overweight patients (1.6% vs. 6.9%, 3.6%, and 2.8%, respectively, p < 0.001). Similarly, 3-year mortality was lowest in patients with obesity (17.1% vs. 28.9%, 24.5% and 18.6%, respectively, p < 0.001). On multivariate analysis, long term all-cause mortality at 3-years remained significantly lower in patients with obesity compared to underweight (HR 1.74, 95% CI: 1.30–2.40, p < 0.001) and normal weight (HR: 1.41, 95% CI:1.21–1.63, p < 0.001) but not in overweight patients (HR: 1.10, 95% CI:0.94–1.28, p = 0.240).

In conclusion, patients with obesity have improved short and long term mortality following TAVR with an observed progressive increase in mortality with lower BMI ranges.