Unprotected Left Main Coronary Artery Disease: Comparison Between Percutaneous Coronary Intervention With Drug-eluting Stents And Coronary Artery Bypass Graft Surgery

BACKGROUND AND OBJECTIVE:based on the clinical benefit in patients treated with coronary artery bypass graft surgery(CABG) over medical therapy, the current guidelines recommend CABG as the standard treatment of unprotected left main coronary artery disease(ULMCA).Since the first percutaneous transluminal coronary angioplasty was performed in 1977, percutaneous coronary intervention of ULMCA has been the focus of interventionist.In the era of bare-metal stents(BMS),several clinical studies showed stents placement in the ULMCA resulted in a higher rate of death and restenosis.So BMS was strictly used in highly selected patients.In recent years,given the lower rate of restenosis using drug-eluting stents(DES)compared with BMS, and improvement in the anti-platelet therapy, intervention therapy of ULMCA gain close attention again. This article aims to assess the prognosis of ULMCA treated with two kinds of strategy, percutaneous coronary intervention with DES and CABG.MATERIAL AND METHODS:From September 2003,to December 2008,458 consecutive patients with ULMCA disease underwent revascularization. Eighty-eight patients(19.2%) failed to conducted telephone contact and were excluded from the analysis, of whom 51 patients in the DES group, and 37 patients in the CABG group(P=0.07).The remaining 370 patients consisituted the retrospective study population. Among them 175 patients received percutaneous coronary intervention with DES, and the others received CABG. The clinical and angiography data was registered referring to the medical history and angiography information.The outcome data was recorded via telephone contact or medical records readmitted. The clinical end points were major adverse cardiac and cerebrovascular event(MACCE),including all caused death, non-fatal myocardial infarction,cerebral vascular events,and target vessel revascularization.RESULTS:The average age of patients were 65±10 years in the DES group,and 67±8 years in the CABG group(P=0.12).Male patients comprised of 84.6% of the DES group, and 89.2% of the CABG group(P=0.18).There were no significant differences between the two groups in the risky factors of hypertention, diabetes mellitus,hyperlipidemia,and smoking history.Compared to the CABG group,more patients received revascularization in the DES group (33.1% vs.10.3%, P<0.01%).There were no significant differences in the clinical diagnosis of stable angina, unstable angina, and acute myocardial infarction. The average Euroscore were 3.8±2.4 in the DES group, and 4.8±2.9 in the CABG group(P<0.01).High risk patients according to the Euroscore system comprised 27.4% of the DES group,and 35.4% of the CABG group(P=0.10).The patients in the DES group were more likely to have isolated left main disease(17.1% vs.3.6%,P<0.01),while the patients in the CABG group had more three vessel diseases and more left main bifurcations.The average SYNTAX score was 21.0±8.2 in the DES group, and 29.6±9.9 in the CABG group(P<0.01).The median follow-up in the PCI group was 790±470 days, and 745±604 days in the CABG group(P=0.45).The 30-day major adverse cardiac and cerebrovascular event(MACCE) rate for DES and CABG was 1.1% and 3.6%,respectively(P=0.24). There were no significant differences between the two groups in the rate of single event such as death, non-fatal myocardial infarction, agent revascularization, and cerebral vascular events.During the follow up, The MACCE-free survival was 88.0% in the DES group, and 76.4% in the CABG group(P=0.02).The patients in the DES group have higher cardiac death-free survival rate than CABG group(98.9% vs.93.3%, P=0.01).The cerebral vascular-free survival rate for DES group and CABG group was 99.4%, and 91.3%, respectively. There was no significant differences in the TVR-free survival rate between DES group and CABG group(93.7%vs.94.9%, P=0.38) The following variables were entered into a stepwise multivariable Cox proportional hazard model for MACCE-free survival and cardiac death-free survival:age, gender, hypertention, diabetes mellitus, smoking, myocardial infarction history, acute myocardial infarction, Euroscore, SYNTAX score, left main plus three vessel diseases and CABG.In the multivariable Cox regression, Euroscore, left main plus three coronary artery diseases were independent predictors of MACCE-free survival and myocardial infarction history, Euroscore, left main plus three coronary artery diseases were independent predictors of cardiac death-free survival. CONCULUSIONS:In our single center experience,the MACCE-free survival was higher in the DES group than CABG group. There were no significant differences in the TVR-free survival between the two groups.CABG group showed a higher rate of cerebral vascular events and cardiac death.