Associated factors and clinical outcomes in mechanical circulatory support use in patients undergoing high risk on-pump cardiac surgery: Insights from the LEVO-CTS trial

Abstract

We describe variables and outcomes associated with peri-operative mechanical circulatory support (MCS) utilization among patients enrolled in the Levosimendan in patients with Left Ventricular Systolic Dysfunction Undergoing Cardiac Surgery Requiring Cardiopulmonary Bypass (LEVO-CTS) trial. In the LEVO-CTS trial, MCS utilization (defined as intra-aortic balloon pump, extracorporeal membrane oxygenation, or surgical ventricular assist device) within 5 days of surgery was examined. The association between MCS use and outcomes including 90-day mortality, 30-day renal-replacement therapy, and hospital and critical stay length of stay were determined. Among the 849 patients from 70 centers randomized to levosimendan or placebo, 85 (10.0%) patients were treated with MCS (71 intra-aortic balloon pump, 7 extracorporeal membrane oxygenation, 7 ventricular assist device); with 89.4% started on post-operative day 0. Inter-institutional use ranged from 0% to 100%. Variables independently associated with MCS utilization included combined coronary artery bypass grafting and valve surgery (adjusted odds ratio [OR] 2.73, 95% confidence interval [CI] 1.70-4.37, P < .001), history of lung disease (OR 1.70, 95% CI 1.06-2.70, P=.029), and history of heart failure (OR 2.44, 95% CI 1.10-5.45, P=.027). Adjusted 90-day mortality (22.4% vs 4.1%, hazard ratio 6.11, 95% CI 3.95-9.44, P < .001) was higher, and median critical care length of stay (8.0 vs 4.0 days, P < .001) was longer in patients managed with MCS. In a randomized controlled trial of high-risk cardiac surgical patients in North America, we observed patient, and surgical variables associated with MCS utilization. MCS use was associated with a higher risk of post-operative mortality.