Impact of body mass index on adverse events after implantation of left ventricular assist devices: An IMACS registry analysis

Academic Article


  • BACKGROUND: Limited data exist describing impact of body mass index (BMI) on post‒left ventricular assist device (post-LVAD) outcomes. We sought to define the relationship between body mass index (BMI) and adverse events (AEs) after LVAD implantation by examining the ISHLT Mechanically Assisted Circulatory Support (IMACS) registry. METHODS: Patients implanted with a contemporary continuous flow (CF)-LVAD were stratified into 4 groups using pre-operative BMI: underweight (UW; BMI ≤18.5 kg/m2); non-obese (NO; BMI >18.5 to <30 kg/m2); obese (OB; BMI ≥30 to <40 kg/m2); and morbidly obese (MO; BMI ≥40 kg/m2). Freedom from AEs was evaluated using the Kaplan–Meier method and risk factors for development of first AE were identified using multiphase parametric hazard modeling. AEs included infection, thromboembolic events, bleeding, device malfunction, and neurologic dysfunction. RESULTS: Between 2013 and 2015, a total of 9,408 patients underwent implantation of a CF-LVAD, which consisted of 368 (4%) UW, 5,719 (61%) NO, 2,770 (29%) OB, and 444 (5%) MO patients. Survival among the 4 BMI cohorts was similar at 2 years (70.8% to 75.8%, p = 0.24). MO patients were less likely to be free from a non‒VAD-related infection (p < 0.0001) or device-related infection (p = 0.0014) at 2 years (50.3%, 70.7%) when compared with OB (58.3%, 78.7%), NO (65.2%, 81.4%), and UW (68.9%, 77.4%) patients. UW (81.5%) and NO (81.3%) patients were more likely to be free from device malfunction at 2 years when compared with OB (78.3%) and MO (72.6%) (p = 0.0006). Thromboembolic events were rare and more common in the UW cohort (p = 0.026). CONCLUSIONS: Although BMI was not correlated with 2-year mortality, an increased rate of infectious and device-related AEs was noted in OB and MO LVAD patients. In a group with few options for transplant, the event morbidity in obese patients can be expected to impact morbidity with longer support durations.
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    Author List

  • Forest SJ; Xie R; Kirklin JK; Cowger J; Xia Y; Dipchand AI; Sivathasan C; Merry C; Lund LH; Kormos R
  • Start Page

  • 1207
  • End Page

  • 1217
  • Volume

  • 37
  • Issue

  • 10