Predictors of Increased Length of Hospital Stay in Patients with Severe Cardiomyopathy Undergoing Coronary Artery Bypass Grafting

Abstract

Objective: Predictors of operative outcome in patients with severely depressed left ventricular ejection fraction (LVEF) undergoing coronary artery bypass grafting (CABG) remain poorly defined. This study aims to identify preoperative variables that are associated with increased postoperative length of hospital stay or operative mortality in this patient population.

Design: Retrospective study.

Setting: Single tertiary care university hospital.

Participants: Patients undergoing isolated CABG between January 2012 and March 2017 with an LVEF ≤ 25%.

Interventions: Isolated CABG.

Measurements and main results: Primary endpoint was a composite of prolonged length of stay, defined as postoperative length of stay >7 days or operative mortality. Of the 201 patients, 99 (49.3%) met the primary endpoint. Patient comorbidities, clinical presentation, presence of Q-waves on electrocardiogram, and echocardiographic parameters including ventricular dimensions and right heart dysfunction were not associated with the primary endpoint. On multivariable analysis, patients who were not on preoperative beta-blockers, patients with preoperative albumin of <3.5 g/dL, and higher Society of Thoracic Surgeons Predicted Risk of Mortality score were associated with increased prolonged length of stay or death.

Conclusions: More than half of patients with severely depressed LVEF undergoing isolated CABG are able to be discharged within 7 days postoperatively. The absence of preoperative beta-blockers, low preoperative albumin levels, and higher Society of Thoracic Surgeons Predicted Risk of Mortality score are associated with more complicated or slower postoperative recovery after CABG in this patient population.

Keywords: cardiomyopathy; coronary artery bypass; length of stay; outcomes.