Body mass index and outcomes after left ventricular assist device placement

Although extremes of body mass index (BMI) are associated with decreased survival after cardiac transplantation, its association with outcomes after left ventricular assist device (LVAD) implantation is not known. This issue is especially important as LVADs are now approved as destination therapy for advanced heart failure patients who are not transplant candidates. In this study, we assess the association between BMI and outcomes after LVAD implantation.

A total of 222 patients who underwent LVAD placement (190 bridge-to-transplant [BTT] and 32 destination therapy) were divided into four groups based on BMI (kg/m2) quartiles (group 1, <22.9; group 2, 22.9 to 26.3; group 3, 26.4 to 29.4; and group 4, >29.4) and were compared for outcomes.

Eighty-four patients died on LVAD support. Six- and 12-month survival on LVAD for the four groups was 35%, 60%, 65%, and 73%, and 26%, 34%, 50%, and 66% (both p < 0.01), respectively. Similar trends were seen for the composite endpoint of survival on LVAD and within 30 days posttransplant among BTT patients. Infectious, neurological, respiratory, or bleeding complications were not related to BMI. Patients with higher BMI tended to have a greater risk of reoperations (43%, 49%, 53%, and 61%, p = 0.06) and renal complications (16%, 33% 23%, 43%, p = 0.03). Age and history of thoracotomy were independently associated with mortality whereas higher BMI was not. Survival was worst for patients with lowest BMI.

Higher BMI did not adversely affect survival after LVAD implantation and therefore relative obesity should not be considered a contraindication for LVAD placement. Further work is needed to understand and manage risks for low BMI patients.