Pre-operative health status and outcomes after continuous-flow left ventricular assist device implantation

Abstract

Background: Health status predicts adverse outcomes in heart failure and cardiac surgery patients, but its prognostic value in left ventricular assist device (LVAD) placement is unknown.

Methods: We examined the association of pre-operative health status, as measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ), with survival and hospitalization after LVAD using the KCCQ score as a continuous variable and stratified by KCCQ score quartile plus missing KCCQ in 1,125 clinical trial participants who received the HeartMate II (Thoratec Corp, Pleasanton, CA) as destination therapy (n = 635) or bridge to transplantation (n = 490).

Results: The mean pre-operative KCCQ score was 29.4 ± 18.7 among survivors (n = 719), and 27.1 ± 18.3 (n = 406) in those who died. In time-to-event analysis for all available follow-up using health status as a continuous variable, the pre-operative KCCQ score did not correlate with overall mortality after LVAD implantation (p = 0.178). Small absolute differences were seen between the pre-operative KCCQ quartile and 30-day survival (Q4 95% vs. Q1 89% vs. missing 87%; p = 0.0009 for trend), 180-day survival (Q4 83% vs. Q1 76% vs missing 79%; p = 0.060 for trend), and days hospitalized at 180 days (Q4 29.8 ± 25.6 vs. Q1 34.1 ± 27.1 vs. missing 36.5 ± 29.9 days; p = 0.009 for trend).

Conclusion: Our findings suggest that pre-operative health status has limited association with outcomes after LVAD implantation. Although these data require further study in a diverse population, mechanical circulatory support may represent a relatively unique clinical situation, distinct from heart failure and other cardiac surgeries, in which heart failure-specific health status measures may be largely reversed.

Keywords: health status; health-related quality of life; heart failure; mechanical circulatory support; risk prediction.