Relation of Body Mass Index to Outcomes in Patients With Heart Failure Implanted With Left Ventricular Assist Devices

Abstract

We aimed at characterizing the impact of low and high body mass index (BMI) on outcomes after left-ventricular assist device (LVAD) surgery and define the predictors of mortality in patients with abnormal BMI (low/high). This study was conducted in 19 centers from 2006 to 2016. Patients were divided based on their baseline BMI into 3 groups of BMI: low (BMI ≤18.5 kg/m²); normal (BMI = 18.5 to 24.99 kg/m²) and high (BMI ≥25 kg/m²) (including overweight (BMI = 25 to 29.99 kg/m²), and obesity (BMI ≥30 Kg/m²)). Among 652 patients, 29 (4.4%), 279 (42.8%) and 344 (52.8%) had a low-, normal-, and high BMI, respectively. Patients with high BMI were significantly more likely men, with more co-morbidities and more history of ventricular/supra-ventricular arrhythmias before LVAD implantation. Patients with abnormal BMI had significantly lower survival than those with normal BMI. Notably, those with low BMI experienced the worst survival whereas overweight or obese patients had similar survival. Four predictors of mortality for LVAD candidates with abnormal BMI were defined: total bilirubin ≥16 µmol/L before LVAD, hypertension, destination therapy, and cardiac surgery with LVAD. Depending on the number of predictor per patients, those with abnormal BMI may be divided in 3 groups of 1-year mortality risk, i.e., low (0 to 1 predictor: 29% and 31%), intermediate (2 to 3 predictors, 51% and 52%, respectively), and high (4 predictors: 83%). In conclusion, LVAD recipients with abnormal BMI experience lower survival, especially underweight patients. Four predictors of mortality have been identified for LVAD population with abnormal BMI, differentiating those a low-, intermediate-, and high risks of death.