Obesity Paradox in Transcatheter Aortic Valve Replacement.

Background: 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).

Methods: 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.

Results: 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).

Conclusion: 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.