The impact of extreme obesity on outcomes after left ventricular assist device implantation

Background: The association between extreme body mass index (BMI) and outcomes in left ventricular assist device (LVAD) patients has not been well established. With the commercial use of LVADs a larger number of patients with a BMI >40 have undergone device implantation. The purpose of this study was to evaluate the short and long-term outcomes of LVAD patients with extreme obesity. Methods: A retrospective review of all patients (n=383) at our center who received a LVAD as primary implant between 2005-2015 was performed. Demographics, preoperative laboratory values, and postoperative outcomes were analyzed. Patients were divided into three groups based on BMI (kg/m(2)) classification (group 1: <= 25; group 2: 25 to 35; group 3: >= 35) and compared using one-way analysis of variance (ANOVA), Kruskal-Wallis and Chi-squared analysis as appropriate. Results: Comparison of postoperative outcomes demonstrated an increased risk of respiratory failure and right ventricular (RV) failure in patients with a BMI >= 35 (range, 35-59). Length of stay, sternal infection, driveline/pocket infection, systemic infection, GI-bleeding, and neurological events within the first year of device therapy were not related to BMI. Survival at 30-day, 1-and 2-year was not significantly different among the three groups. The group with the smallest BMI demonstrated an increased risk for re-operative bleeding. Conclusions: Despite an increased risk of early morbidity in patients with extreme obesity, long term survival was not significantly different between the BMI groups. Careful consideration is recommended when evaluating patients with an excessive BMI for LVAD therapy although it should not be a contraindication for device placement.