Objective: To evaluate the effect of body mass index (BMI) on outcomes of patients with severe aortic stenosis (AS) undergoing trans-catheter aortic valve implantation (TAVI), and to examine the validity of the "obesity paradox" in this population.
Background: A considerable number of studies showed better outcomes for overweight patients after percutaneous and surgical cardiovascular interventions in general, and after surgical aortic valve replacement in particular, the so called "obesity paradox".
Methods: The data of 409 consecutive patients undergoing TAVI in our medical center was analyzed. Patients were categorized into 4 groups according to BMI: underweight (<18.4 kg/m2), normal weight (18.5 to 24.9 kg/m2), overweight (25 to 29.9 kg/m2), and obese (>30 kg/m2). All procedure related complications were recorded, as well as 30-day and 1 year all-cause mortality rates.
Results: Five (1%) patients were underweight, 133 (32.5%) patients had normal weight, 169 (41.5%) were overweight, and 102 (25 %) were obese. The obese patients had a higher prevalence of co-morbidities and higher incidence of vascular complications compared with the normal weight patients (16% vs. 7% p=0.013). Nevertheless, 30- day mortality was similar among the groups while 1 year mortality was lower among the overweight and obese patients (BMI≥25) (P=0.038). After adjusting for differences in baseline characteristics, BMI was found to be independently associated with improved survival following TAVI (HR 0.94, CI 0.89-0.99, p=0.042).
Conclusions: In this single center study of high-risk patients undergoing trans-femoral TAVI, obesity and overweight were independently associated with better outcome, supporting the "obesity paradox" in this specific population.
