Obese patients and mechanical circulatory support: weight loss, adverse events, and outcomes

Obesity and heart failure are increasingly common, but the outcomes, weight changes, and adverse events of patients with advanced heart failure and obesity on mechanical support is not well described.

We retrospectively reviewed all non-underweight patients with durable mechanical support at a single institution from January 2000 until December 2008 and compared outcomes, weight change, and Interagency Registry for Mechanically Assisted Circulatory Support-defined adverse events between obese and nonobese patients.

A total of 169 patients were included; 113 (67%) nonobese and 56 (33%) obese. Baseline characteristics, pump types, and implant duration were similar for both populations with the exception of more diabetes (61% vs 26%, p < 0.0001) and hypertension (61% vs 42%, p = 0.019) in the obese. Outcomes on mechanical support at 6 months were not different between groups. There was no significant difference between the nonobese and obese groups in the change in body mass index (-0.3 vs -1.0 mg/m(2), p = 0.29) over the duration of support. Obese patients, as compared with the nonobese, had higher incidence rates of sepsis (64.5% vs 34.7%, respectively, p = 0.006) and reoperation for infectious complications (34.2% vs 13.3%, respectively, p = 0.014). Obese patients also had a higher cumulative incidence of sepsis and reoperation for infection. Two-year posttransplant outcomes were not different in the obese and nonobese.

Obese patients have similar outcomes on mechanical support, but at the cost of a higher cumulative incidence of sepsis and reoperations for infection; however, obese patients lose little weight while on mechanical support.