Metabolic Dysfunction in Continuous‐Flow Left Ventricular Assist Devices Patients and Outcomes

Abstract

Background Metabolic impairment is common in heart failure patients. Continuous‐flow left ventricular assist devices (CF‐LVADs) improve hemodynamics and outcomes in patients with advanced heart failure; however, the effect of CF‐LVADs on metabolic status is unknown. This study aims to evaluate the changes in metabolic status following CF‐LVAD implantation and measure the correlation of metabolic status with outcomes. Methods and Results Prospective data on CF‐LVAD patients were obtained. Metabolic evaluation, including hemoglobin A1C, free and total testosterone, thyroid‐stimulating hormone (TSH), and free T4, was obtained before and at multiple time points following implantation. Patients with nonelevated thyroid‐stimulating hormone and normal hemoglobin A1C and testosterone levels were defined as having normal metabolic status. Baseline characteristics, hemodynamics, and outcomes were collected. One hundred six patients were studied, of which 56 had paired data at baseline and 1‐ to 3‐month follow‐up. Before implantation, 75% of patients had insulin resistance, 86% of men and 39% of women had low free testosterone, and 44% of patients had abnormal thyroid function. There was a significant improvement in hemoglobin A1C, free testosterone, and thyroid‐stimulating hormone following implantation (P<0.001 for all). Patients with normal hemoglobin A1C (<5.7%) following implantation had higher 1‐year survival free of heart failure readmissions (78% versus 23%; P<0.001). Patients with normal metabolic status following implantation also had higher 1‐year survival free of heart failure readmissions (92% versus 54%; P=0.04). Conclusions Metabolic dysfunction is highly prevalent in advanced heart failure patients and improves after CF‐LVAD implantation. Normal metabolic status is associated with a significantly higher rate of 1‐year survival free of heart failure readmissions.