Long-term outcome of surgical revascularisation in patients with reduced left ventricular ejection fraction-a population based cohort study

Abstract

BACKGROUND: Surgical revascularization is an established indication for patients with advanced coronary artery disease and reduced left ventricular ejection fraction (LVEF). Long-term outcomes for these patients are not well defined. We studied the long-term outcomes of patients with ischaemic cardiomyopathy who underwent surgical revascularization in a well-defined nationwide cohort. MATERIALS AND METHODS: A retrospective study on 2,005 patients that underwent isolated coronary artery bypass grafting (CABG) in Iceland between 2000-2016. Patients were catagorized into two groups based on their preoperative LVEF; LVEF ≤35% (n = 146, median LVEF 30%) and LVEF >35% (n = 1859, median LVEF 60%). Demographics and major adverse cardiac and cerebrovascular events (MACCE), were compared between groups along with cardiac-specific and overall survival. Mean follow-up was 7.6 years. RESULTS: Demographics were similar in both groups regarding age, gender, and most cardiovascular risk factors. However, patients with LVEF ≤35% more often had diabetes, renal insufficiency, chronic obstructive pulmonary disease and a previous history of myocardial infarction. Thirty-day mortality was four times higher (8% vs 2%, p < 0.001) in the LVEF ≤35%-group compared to controls. MACCE-free survival was 83% and 62% at 1 and 5 years for LVEF ≤35%-group compared to 94% and 82% for the control group. Overall survival was also significantly lower in the same groups, or 87% and 69% (p < 0.001) compared to 98% and 91% (p < 0.001), at 1 and 5 years respectively. CONCLUSIONS: A good long-term outcome after CABG can be expected for patients with reduced LVEF, however, their survival is still significantly inferior to patients with normal ventricular function.