Outcomes and Predictors of In-Hospital Mortality After Isolated Coronary Artery Bypass Grafting in Patients with Severe Ischemic Cardiomyopathy: A Single-Centre Retrospective Analysis

Background: Patients with coronary artery disease (CAD) and severely reduced left ventricular ejection fraction (LVEF) ≤ 30% represent a high-risk group for coronary artery bypass grafting (CABG). Outcomes are of significant concern; therefore, real-world outcome data and predictors of early mortality remain important for perioperative decision-making. Aim: This study aims to evaluate early and mid-term outcomes in patients with severe ischemic cardiomyopathy (LVEF ≤ 30%) undergoing isolated CABG and to identify independent predictors of in-hospital mortality. Methods: We conducted a retrospective single-centre cohort analysis including patients with preoperative LVEF ≤ 30% undergoing isolated CABG (2017–2021). Early outcomes included in-hospital and 30-day mortality. The mid-term outcome was all-cause mortality up to 36 months. Multivariable logistic regression was used to identify independent predictors of in-hospital mortality. A predefined subgroup comparison was performed for LVEF ≤ 20% versus LVEF 20–30%. Results: The study comprised 147 patients with LVEF ≤ 30% undergoing isolated CABG. Overall, in-hospital mortality was 21.1%, and 30-day mortality was 23.8%. Cumulative all-cause mortality was 31.3%, 37.4%, and 42.9% at 12, 24 and 36 months respectively. Patients with LVEF ≤ 20% showed significantly higher early mortality (in-hospital 37.2% vs. 14.4%; 30-day 41.9% vs. 16.3%) and 36-month mortality (58.1% vs. 36.5%) compared with those with LVEF at 20–30%. Independent predictors of in-hospital mortality included preoperative hemodynamic instability, elevated operative risk scores, emergency status, prolonged cardiopulmonary bypass time, and major postoperative complications (all p < 0.05). Conclusions: CABG in patients with LVEF ≤ 30% is associated with substantial early mortality, while mid-term survival remains acceptable. Severely reduced LVEF identifies a particularly high-risk subgroup requiring careful perioperative risk stratification.