Trends, Outcomes, and Readmissions Among Left Ventricular Assist Device Recipients with Acute Kidney Injury Requiring Hemodialysis

Abstract

Although renal function may improve after left ventricular assist devices (LVAD) implantation, acute kidney injury (AKI) requiring hemodialysis (HD) therapy can occur postoperatively. We used data from the National Readmissions Database to calculate annual rates of in-hospital outcomes and readmissions among patients who underwent implantation and developed acute kidney injury (AKI) requiring hemodialysis (HD) for years 2012–2015. We identified 178 (weighted 469) patients with AKI requiring HD after LVAD implantation. In-hospital mortality was significantly higher among LVAD recipients who required HD for AKI compared with those who did not (42.38% vs. 8.38%, p < 0.001). Rates of in-hospital mortality (from 52.1% in 2012 to 33.9% in 2014, p = 0.046) and length of stay (from 60.3 days in 2012 to 47.1 days in 2014, p = 0.003) decreased significantly, whereas there was a trend toward reduced hospital cost (from $320,414 in 2012 to $267,285 in 2014, p = 0.076) during the study period. However, postoperative bleeding increased significantly (p = 0.01). Acute kidney injury requiring HD after implantation was not associated with significantly higher rates of readmissions compared with LVAD recipients without AKI on HD, after adjustment for clinical and hospital characteristics (41.4% vs. 30.5%; odds ratio 1.28; 95% confidence interval [CI]: 0.85–1.95; P = 0.239). However, 5.42% of these patients required maintenance hemodialysis in readmissions. In-hospital mortality and length of stay are decreasing but remain unacceptably high in patients requiring HD for AKI after LVAD implantation but remain higher than LVAD recipients without AKI on HD. A minority of these patients who survive hospital discharge require maintenance hemodialysis.