Renal Replacement Therapy in Patients Undergoing Continuous-Flow Left Ventricular Assist Devices (LVADs)

Abstract

Purpose Acute renal dysfunction in heart failure patients receiving LVADs is common. Outcomes of patients requiring renal replacement therapy (RRT) after LVAD implant are unclear. The objective of this study is to assess the outcomes of patients undergoing emergent RRT after receiving HeartMateII (HMII) LVADs. Methods and Materials A retrospective chart review of 211 patients receiving HMII LVADs was performed. RRT was defined as post-op intermittent hemodialysis (IHD), and/or continuous veno-venous hemodialysis (CVHHD). Results 19 out of 211 (9%) patients required RRT post-op (15 had HM II, 4 required additional RVAD). Of these, 14 (74%) received temporary CVHHD, while 5 (26%) received IHD following CVVHD (combined RRT). Indications for RRT were ATN (80%), and acidosis/hyperkalemia (20%). Overall in-hospital mortality rate was 53% (9/14 [64%] in CVHHD, and 1/5 [20%] in combined RRT). There were no differences in demographics, comorbidities, and baseline end-organ function between patients requiring RRT and those not requiring RRT, except for reduced baseline GFR in the RRT group ( table 1 ). 15 out of 19 (80%) patients required RRT intervention within 7 days of LVAD implant, and the median number of days on RRT for survivors was 15 days. All survivors returned to baseline renal function at 6 months. Conclusions Majority of patients receiving HMII LVAD do not require RRT. However, the need for RRT in the post implant period is associated with significant post-op mortality. Studies to identify patients at risk for requiring RRT and strategies to optimize renal function in the peri-op period is important to improve clinical outcomes. no RRT RRT p-value Total 192 19 Age 56±15 57.5±7.5 0.4 Male 80% 89% 0.3 Ischemic Etiology 54% 63% 0.5 CHF 89% 89% 0.96 Prior MI 38% 47% 0.4 Prior CVA 7% 5% 0.8 COPD 19% 16% 0.7 Diabetes 37% 42% 0.7 CKD 26% 37% 0.3 Chronic Liver Disease 3% 11% 0.1 Pre-op Creatinine (mg/dL) 1.4±0.6 1.6±0.6 0.08 Pre-op BUN (mg/dL) 32±19 37± 15 0.2 Pre-op GFR (mL/min/1.7m2) 58±21 48.5±21 0.03* Pre-op AST (U/L) 75±304 313±650 0.07