The Neutrophil-Lymphocyte Ratio and Survival During Left Ventricular Assist Device Support

Abstract

Systolic heart failure (HF) is a low-grade systemic inflammatory state. Neutrophil-lymphocyte ratio (NLR) is a nonspecific inflammatory marker with prognostic value in HF. We aimed to determine the relationship between NLR and mortality during left ventricular assist device (LVAD) support. We retrospectively reviewed LVAD recipients implanted in the years 2010-2018. NLR was recorded before LVAD implantation and at intervals during LVAD support; pre-LVAD and 90-day LVAD NLRs were compared. Cox proportional hazard models were constructed to study the impact of NLR, both before LVAD implantation and at 90 days with LVAD, on mortality during subsequent LVAD support. Among 301 subjects, the median pre-LVAD NLR was 4.7 (interquartile range 3.0-8.0). Higher pre-LVAD NLR was independently associated with increased mortality during a median 324 days of LVAD support (adjusted hazard ratio [HR] 1.03, 95% confidence interval [CI] 1.01-1.06; P = .012, adjusted for pre-LVAD age, HF etiology, white blood count, hemoglobin, blood urea nitrogen, and sodium). After LVAD implantation, the NLR rose initially and then plateaued lower by day 90. Despite the mean decrease, higher 90-day LVAD NLR remained independently associated with increased mortality (adjusted HR 1.06, 95% CI 1.01-1.13; P = .033, stratified by early infection events). Higher pre-LVAD NLR is independently associated with mortality during LVAD support. NLR improves during LVAD support, but even accounting for early infections, a higher NLR at day 90 remains associated with subsequent mortality.