BackgroundComplete revascularization of coronary artery disease has been linked to improved outcomes in patients with preserved left ventricular (LV) function. ObjectivesThis study sought to identify the impact of complete revascularization in patients with severe LV dysfunction. MethodsPatients enrolled in the REVIVED-BCIS2 (Revascularization for Ischemic Ventricular Dysfunction) trial were eligible if baseline/procedural angiograms and viability studies were available for analysis by independent core laboratories. Anatomical and viability-guided completeness of revascularization were measured by the coronary and myocardial revascularization indices (RIcoro and RImyo), respectively, where RIcoro = (change in British Cardiovascular Intervention Society Jeopardy score [BCIS-JS]) / (baseline BCIS-JS) and RImyo= (number of revascularized viable segments) / (number of viable segments supplied by diseased vessels). The percutaneous coronary intervention (PCI) group was classified as having complete or incomplete revascularization by median RIcoro and RImyo. The primary outcome was death or hospitalization for heart failure. ResultsOf 700 randomized patients, 670 were included. The baseline BCIS-JS and SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) scores were 8 (Q1-Q3: 6-10) and 22 (Q1-Q3: 15-29), respectively. In those patients assigned to PCI, median RIcoro and RImyo values were 67% and 85%, respectively. Compared with the group assigned to optimal medical therapy alone, there was no difference in the likelihood of the primary outcome in those patients receiving complete anatomical or viability-guided revascularization (HR: 0.90; 95% CI: 0.62-1.32; and HR: 0.95; 95% CI: 0.66-1.35, respectively). A sensitivity analysis by residual SYNTAX score showed no association with outcome. ConclusionsIn patients with severe LV dysfunction, neither complete anatomical nor viability-guided revascularization was associated with improved event-free survival compared with incomplete revascularization or treatment with medical therapy alone. (Revascularization for Ischemic Ventricular Dysfunction) [REVIVED-BCIS2]; NCT01920048)