Data is controversial regarding the existence of an “obesity paradox” in patients undergoing Transcatheter Aortic Valve Replacement (TAVR).

We sought to investigate the prognostic value of body mass index (BMI) on short- and mid-term outcomes following TAVR.

This is an observational single-center study involving all patients who underwent TAVR from 2009 to 2019. BMI was calculated in all patients before TAVR. The cohort was subdivided into four subgroups: underweight (<20kg/m²), normal weight (≥20 to <25kg/m²), overweight (≥25 to <30kg/m²) and obese (≥30kg/m²).

A total of 412 patients (mean age 79.6±7.8 years, mean STS score 5.3±3.6) were included., and subdivided as follows: underweight (n=35, 8.5%), normal weight (n=121, 29.4%), overweight (n=140, 34%) and obese (n=116, 28.1%). Obese patients were younger, included more females and had lower STS score; whereas underweight patients were older, had higher STS score, more chronic kidney disease, more left ventricular dysfunction and more often underwent non transfemoral TAVR. BMI predicted 30-day survival (AUC:0.692 [95%CI 0.522–0.862]; P=0.030) with an optimal cut-off of 24.4 (sensitivity=66.6%, specificity=63.6%).

Thirty-day mortality was higher in underweight group (8.3%) in comparison with other BMI subgroups (normal weight 2.5%, overweight 1.4%, obese 0.9%; P=0.045). However, no significant difference was found after adjustment of confounders (all P=NS).

BMI did not predict one-year mortality. No significant difference in one-year survival was observed between the four BMI subgroups (log rank P=0.925) (Figure 1).

BMI could represent an interesting prognostic tool for short-term mortality in patients undergoing TAVR. Our data supports the proposition that underweight patients are at higher risk for procedural complications. For 30-day survivors, no evidence for the existence of an obesity paradox was observed at one year.