PRESENCE OF ANGIOGRAPHIC CORONARY COLLATERALS PREDICTS MYOCARDIAL RECOVERY AFTER CORONARY-BYPASS SURGERY IN PATIENTS WITH SEVERE LEFT-VENTRICULAR DYSFUNCTION

Background-Patients with coronary artery disease and left ventricular dysfunction (LVD) may have areas of hibernating myocardium that improv e functionally after revascularization. Coronary collateral circulatio n may sustain ischemic, dysfunctional myocardium and favor myocardial recovery after revascularization. We evaluated the effect of angiograp hic coronary collaterals on myocardial functional recovery after coron ary bypass graft (CABG) surgery in a group of patients with severe LVD . Methods and Results-Forty-one patients with multivessel coronary art ery disease and advanced LVD (left ventricular ejection fraction [LVEF ] 25+/-5%) undergoing CABG were identified from a prospective database , Preoperative coronary angiograms were evaluated for collaterals, whi ch were graded according to Rentrop's classification (0 to 3), and a c ollateral index was calculated (collateral sum divided by 3). Preopera tive and postoperative radionuclide ventriculograms provided global LV EF and regional ejection fractions. Of 123 regions evaluated, 120 were dysfunctional at baseline. Virtually all (122 of 123) regions were su btended by an artery with greater than or equal to 70% stenosis that w as bypassed. Thirty-eight (81%) of 47 dysfunctional regions with grade 2 or 3 collaterals improved regional ejection fraction after surgery versus 38 (52%) of 73 dysfunctional regions with grade 0 or 1 collater als (P=0.0018), Global LVEF was 34+/-10% after surgery (P<0.001 versus before surgery). Among patients with a global LVEF increase greater t han or equal to 10%, collateral index was 1.81 versus 0.83 in those wi th an LVEF increase <10% (P=0.005). Conclusions-In this population of patients with coronary artery disease with severe LVD, the presence of angiographic grade 2 or 3 collaterals predicted recovery of regional and global myocardial function after CABG.