Extremes of body mass index do not impact mid-term survival after continuous-flow left ventricular assist device implantation.
BACKGROUND
Extremes of body mass index (BMI) are often considered contraindications to use of a left ventricular assist device (LVAD), but data regarding outcomes across the spectrum of BMI are limited. We sought to assess the association of BMI with survival and major morbidity after continuous-flow (CF) LVAD implantation.


METHODS
Patients (n = 896) enrolled in the HeartMate II LVAD bridge-to-transplantation and destination therapy trials were divided into 4 BMI groups: underweight (<18.5 kg/m(2)); normal (18.5 kg/m(2) ≤ BMI < 30 kg/m(2)); obese (30 kg/m(2) ≤ BMI < 35 kg/m(2)); and extremely obese (≥35 kg/m(2)). The association of BMI with survival was tested using Kaplan-Meier analysis and proportional hazards regression. Major adverse events were compared using Poisson's regression and chi-square tests.


RESULTS
At implantation, 48 (5%) patients were underweight, 596 (67%) normal weight, 164 (18%) obese and 88 (10%) extremely obese. BMI extremes were associated with differences in creatinine, albumin, age, central venous pressure and etiology. BMI was not associated with survival in the univariate analysis (p = 0.83) or in adjusted models (extremely obese: hazard ratio [HR] 1.29, p = 0.231; obese: HR 0.94, p = 0.723; underweight: HR 1.23, p = 0.452). Underweight patients were more likely to have bleeding events (p < 0.001), whereas extremely obese patients had higher rates of device-related infection (p = 0.041) and rehospitalization (p = 0.014).


CONCLUSIONS
Overall survival in patients receiving CF LVAD is similar across BMI categories. Carefully selected patients at both extremes of BMI have good mid-term survival after LVAD and should be considered for LVAD implantation relative to overall risk profile.
Heart & Vascular Institute, Henry Ford Hospital, Detroit, Michigan, USA. rbrewer1@hfhs.org
Robert J
RJ
Brewer
David E
DE
Lanfear
Chittoor B
CB
Sai-Sudhakar
Kartik S
KS
Sundareswaran
Yazhini
Y
Ravi
David J
DJ
Farrar
Mark S
MS
Slaughter
D000328:Adult; D000368:Aged; D015992:Body Mass Index; D005260:Female; D006353:Heart-Assist Devices; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000401:mortality*; D019919:Prosthesis Implantation / Q000379:methods / Q000401:mortality*; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D013851:Thinness / Q000401:mortality*; D016896:Treatment Outcome