Risk Factors for Renal Failure after Continuous-Flow Left Ventricular Assist Device Implantation

Abstract

Renal failure after continuous-flow Left ventricular assist device (CF-LVAD) implantation increases the risk of death. Although CF-LVAD improve hemodynamic status and affect renal function, there was no study which analyzed the relationship of hemodynamics and renal function after CF-LVAD implantation. Then, we investigated that risk factors for renal failure (RF) in the chronic phase after CF-LVAD implantation using postoperative hemodynamic data. Between October 2005 and August 2018, 191 consecutive patients underwent CF-LVAD implantation at Osaka University Hospital. Of these, 76 who recorded postoperative right heart catheterization were included (mean age, 42 ± 13 years; 38% were women). We used 5 different types of CF-LVADs (HeartMate II: 50%, DuraHeart:13%, Jarvik2000:13%, EVAHEART:16%, HeartWare:8%. Preoperative and postoperative RF was defined that estimated glomerular filtration rate (eGFR) < 60mL/min/1.73m2 at preoperative and postoperative 1 year, respectively. We analyzed the course of renal function after CF-LVAD implantation and the risk factors for RF in the chronic phase. Two weeks after implantation, the mean eGFR was improved from 70 (47-90) to 101 (73-131) mL/min/1.73 m2. However, the renal function showed gradual decline and eGFR was 70 (60-93) mL/min/1.73 m2 at postoperative 1year. There were 17(22%) patients who developed RF at postoperative 1year. Multivariate analysis revealed that preoperative RF (OR, 10.2; 1.66-63.2; p = 0.006) and postoperative higher level of systemic vascular resistance index (SVRI) (OR, 1.19; 1.00-1.42; p = 0.020) were risk factors for RF in the chronic phase. On the other hand, among patients with preoperative low cardiac index (CI < 2.2 L/min/m2), preoperative RF was not risk factor for postoperative RF. Renal function improved immediately after CF-LVAD implantation, however, gradually decrease to the baseline after the transient improvement. Patients with preoperative RF significantly related to postoperative RF significantly, which was particularly noticeable in patients with preoperative CI was maintained. Elevated SVRI, which can be related to peripheral circulatory failure, was significant risk factor for postoperative RF and thus adequate management of elevated SVRI has the possibility to maintain postoperative renal function for CF-LVAD patients.