Predictors and Outcomes of Continuous Veno-venous Hemodialysis Use After Implantation of a Left Ventricular Assist Device

Abstract

Post-operative renal failure is a common complication after left ventricular assist device (LVAD) implantation. This study was designed to evaluate predictors and outcomes of acute renal failure after LVAD insertion. Two-hundred one patients undergoing LVAD implantation at a single institution from June 1996 through April 2004 were retrospectively analyzed. Patients were categorized into 2 groups: those who required post-operative continuous veno-venous hemodialysis (CVVHD) (Group 1, n = 65, 32.3%) and those who did not (Group 2, n = 136, 67.7%). Independent predictors of post-operative renal failure requiring CVVHD were determined using multivariate logistic regression techniques. Patients who had post-operative renal failure requiring CVVHD were older (53.7 +/- 12.9 vs 48.2 +/- 14.2 years, p = 0.009), had a higher incidence of intra-aortic balloon pump use (46.6% vs 26.2%, p = 0.006), and had a higher pre-operative mean LVAD score (5.8 +/- 3.5 vs 3.8 +/- 3.3, p = 0.001) than those without renal failure. LVAD score was the only independent predictor of post-operative renal failure requiring CVVHD (odds ratio = 1.226, p = 0.006). Sepsis rate was higher (33.3% vs 6.9%, p < 0.001) and bridge-to-transplantation rate was lower (52.4% vs 83.5%, p < 0.001) in Group 1 than in Group 2. Post-LVAD survival rates at 1, 3, 5 and 7 years for Group 1 and Group 2 were 43.2%, 39.1%, 34.7% and 34.7% vs 79.2%, 74.0%, 68.3% and 66.4%, respectively (log rank, p < 0.001). Acute renal failure necessitating CVVHD remains a serious complication after LVAD and confers significant morbidity and mortality. Pre-operative evaluation of patient risk factors and optimization of peri-operative hemodynamics are of utmost importance to prevent this major complication.