PURPOSE: To evaluate the effect of coronary artery bypass graft surgery (CABG) on ischemic asymptomatic episodes (IAE). METHODS: Twenty eight males (mean age 57.3±9.6 years) with stable angina and no microcirculation abnormalities, who presented with IAE after medication withdrawal, were studied using ambulatory electrocardiography monitoring. Presence of IEA was analyzed before and 4 months after CABG according to its frequency and heart rate (HR) response. CAGB was considered complete in 75% of the cases. RESULTS: The number of IAE was reduced from 162 (9 symptomatic) in the preoperative period to 4 after surgery (p<0.05). In two patients with IAE in the postoperative period, coronariography confirmed obstruction of aortocoronary grafts. Analysis of HR at the beginning and peak of IAE suggested as mechanisms both reduced blood flow and increased oxygen consumption by the myocardium. CONCLUSION: CABC eliminated IAE regardless of HR. When IAE is present after surgery, graft occlusion should be suspected.
coronary artery bypass graft surgery; ischemic asymptomatic episodes
