The Incidence and Risk Factors of Acute Kidney Injury After Left Ventricular Assist Device Implantation

Abstract

Objective: Left ventricular assist device surgery (LVAD) associated acute kidney injury (AKI) is a severe complication of cardiac surgery with 15-45% incidence. The study evaluated AKI in the early postoperative period after LVAD surgery using the Kidney Disease: Improving Global Outcomes (KDIGO) criteria and compare patients with and without AKI to determine the incidence, risk factors, and clinical outcomes.

Materials and Methods: In this retrospective cohort study, the medical records of all patients aged between 18 and 75 years who underwent LVAD implantation from January 2011 to December 2016 were reviewed. Patients were divided into two groups based on the development of AKI to analyze demographic features and perioperative variables. AKI was defined according to the KDIGO criteria.

Results: Out of 57 patients, 10 (18%) were female, and the cohort's mean age was 44.6 +/- 16.1 years. Thirty-six patients (63%) developed AKI following LVAD implantation. Logistic regression analysis revealed the duration of cardiopulmonary bypass (CPB), mean arterial pressure, and cumulative fluid balance on the first postoperative day as independent risk factors for AKI [odds ratio (OR): 1.013, confidence interval (CI) 95% 1.000-1.025, p=0.05; OR: 0.929, CI 95% 0.873-0.989, p=0.02; OR: 1.001, CI 95% 1.000-1.001, p=0.04 respectively]. Hospital mortality (58% vs. 24%, p=0.01) and 30-day mortality (39% vs. 5%, p=0.01) were significantly higher in patients who had AKI.

Conclusion: Risk factors for the occurrence of AKI include a longer duration of CPB, lower mean arterial pressures, and higher cumulative fluid balance on the first postoperative day. Therefore, AKI is one of the most important causes of morbidity and mortality after LVAD.