Abstract 728: Coronary Revascularization Therapy for Chronic Coronary Artery Disease may Increase Cardiac Events Compared with Medical Therapy in Patients with Prior Myocardial Infarction who Showed Less Extent of Ischemia Detected by ECG-Gated Stress Tc-99m Tetrofosmin Myocardial Perfusion SPECT: A Sub-Analysis of the J-ACCESS Study
Coronary revascularization therapy for chronic coronary artery disease (CAD) may reduce cardiac events in patients with greater extent of myocardial ischemia, while medical therapy only without revascularization may improve prognosis in high-risk patients with prior myocardial infarction (MI) who showed less extent of myocardial ischemia. The effects of revascularization on cardiac events were evaluated in chronic CAD patients who underwent gated stress/rest myocardial perfusion SPECT study (n=4360, age=66, LVEF=60%). Coronary revascularization was performed in 375 patients within 60 days after SPECT study. Patients were divided into four groups based on the extent of ischemia and performance of revascularization. Group 1 (ischemic myocardium <10% with revascularization, n=270), group 2 (ischemic myocardium <10% without revascularization, n=3746), group 3 (ischemic myocardium ≥10% with revascularization n=105), group 4 (ischemic myocardium ≥10% without revascularization n=285). The outcome was cardiac death, nonfatal MI, and congestive heart failure requiring hospitalization during a follow-up period of 3 years. Patients with prior MI (n=1327) showed higher incidence of cardiac events than those without (7.6% vs. 3.0%, p<0.001). In patients without prior MI (n=3043), there was no difference in the incidence of cardiac events between patients with revascularization therapy and those without (4.1% in group 1 vs. 2.7% in group 2, p=0.42; 2.8% in group 3 vs. 6.0% in group 4, p=0.31), and the incidence of cardiac events was increased in the patients with greater extent of ischemia (≥10%) compared with those with less extent of ischemia (6.0% vs. 2.7%, p=0.02). In patients with prior MI who showed ischemic myocardium <10%, revascularization therapy increased cardiac events compared with medical therapy only (13.9% vs. 7.0%, p=0.009), although there was no difference in left ventricular ejection fraction between two groups. Coronary revascularization therapy should be carefully chosen in chronic CAD patients with prior MI who showed less extent of myocardial ischemia <10% because medical therapy without revascularization may improve prognosis in those patients.