Frailty and outcomes after implantation of left ventricular assist device as destination therapy

Abstract

Background: Frailty is recognized as a major prognostic indicator in heart failure. There has been interest in understanding whether pre-operative frailty is associated with worse outcomes after implantation of a left ventricular assist device (LVAD) as destination therapy.

Methods: Patients undergoing LVAD implantation as destination therapy at the Mayo Clinic, Rochester, Minnesota, from February 2007 to June 2012, were included in this study. Frailty was assessed using the deficit index (31 impairments, disabilities and comorbidities) and defined as the proportion of deficits present. We divided patients based on tertiles of the deficit index (>0.32 = frail, 0.23 to 0.32 = intermediate frail, <0.23 = not frail). Cox proportional hazard regression models were used to examine the association between frailty and death. Patients were censored at death or last follow-up through October 2013.

Results: Among 99 patients (mean age 65 years, 18% female, 55% with ischemic heart failure), the deficit index ranged from 0.10 to 0.65 (mean 0.29). After a mean follow-up of 1.9 ± 1.6 years, 79% of the patients had been rehospitalized (range 0 to 17 hospitalizations, median 1 per person) and 45% had died. Compared with those who were not frail, patients who were intermediate frail (adjusted HR 1.70, 95% CI 0.71 to 4.31) and frail (HR 3.08, 95% CI 1.40 to 7.48) were at increased risk for death (p for trend = 0.004). The mean (SD) number of days alive out of hospital the first year after LVAD was 293 (107) for not frail, 266 (134) for intermediate frail and 250 (132) for frail patients.

Conclusions: Frailty before destination LVAD implantation is associated with increased risk of death and may represent a significant patient selection consideration.

Keywords: destination; frailty; heart failure; left ventricular assist device; mortality; readmission.

Figure 1. One-Year Mortality According to Tertiles of the Frailty Deficit Index

Figure 2. Risk of Death and Rehospitalization by Frailty Tertiles

The Kaplan Meier curves for death are shown by tertiles of the frailty Deficit Index (lowest= not frail, middle= intermediate frail, highest= frail, panel A). The mean number of hospitalizations over time are shown by frailty tertiles (panel B).

Figure 2. Risk of Death and Rehospitalization by Frailty Tertiles

The Kaplan Meier curves for death are shown by tertiles of the frailty Deficit Index (lowest= not frail, middle= intermediate frail, highest= frail, panel A). The mean number of hospitalizations over time are shown by frailty tertiles (panel B).