Extent of Coronary and Myocardial Disease and Benefit From Surgical Revascularization in LV Dysfunction

Abstract

BackgroundPatients with ischemic left ventricular dysfunction have higher operative risk with coronary artery bypass graft surgery (CABG). However, those whose early risk is surpassed by subsequent survival benefit have not been identified. ObjectivesThis study sought to examine the impact of anatomic variables associated with poor prognosis on the effect of CABG in ischemic cardiomyopathy. MethodsAll 1,212 patients in the STICH (Surgical Treatment of IsChemic Heart failure) surgical revascularization trial were included. Patients had coronary artery disease (CAD) and ejection fraction (EF) of ≤35% and were randomized to receive CABG plus medical therapy or optimal medical therapy (OMT) alone. This study focused on 3 prognostic factors: presence of 3-vessel CAD, EF below the median (27%), and end-systolic volume index (ESVI) above the median (79 ml/m2). Patients were categorized as having 0 to 1 or 2 to 3 of these factors. ResultsPatients with 2 to 3 prognostic factors (n = 636) had reduced mortality with CABG compared with those who received OMT (hazard ratio [HR]: 0.71; 95% confidence interval [CI]: 0.56 to 0.89; p = 0.004); CABG had no such effect in patients with 0 to 1 factor (HR: 1.08; 95% CI: 0.81 to 1.44; p = 0.591). There was a significant interaction between the number of factors and the effect of CABG on mortality (p = 0.022). Although 30-day risk with CABG was higher, a net beneficial effect of CABG relative to OMT was observed at >2 years in patients with 2 to 3 factors (HR: 0.53; 95% CI: 0.37 to 0.75; p<0.001) but not in those with 0 to 1 factor (HR: 0.88; 95% CI: 0.59 to 1.31; p = 0.535). ConclusionsPatients with more advanced ischemic cardiomyopathy receive greater benefit from CABG. This supports the indication for surgical revascularization in patients with more extensive CAD and worse myocardial dysfunction and remodeling. (Comparison of Surgical and Medical Treatment for Congestive Heart Failure and Coronary Artery Disease [STICH]; NCT00023595)