INFLUENCE OF BYPASS-GRAFTING TO THE INFARCT ARTERY ON LATE POTENTIALSIN CORONARY OPERATIONS

Background. Late potentials (LPs) after myocardial infarction identify the risk of arrhythmic events and sudden death, and the absence of an terograde flow in the infarct-causing occluded coronary artery frequen tly is associated with LPs on signal-averaged electrocardiography. The present study was designed to clarify the influence of revascularizat ion of the infarct artery on the LPs in the late course after myocardi al infarction. Methods. We studied 21 patients after myocardial infarc tion with positive LPs who had at least one occluded infarct coronary artery. We investigated the LPs on signal-averaged electrocardiograms on the day of elective coronary artery bypass grafting (CABG) and 1 we ek after CABG. Results. There were 25 infarct arteries in the study pa tients, 13 of which were grafted. The positive LPs disappeared soon af ter CABG in 13 patients, 10 of whom had grafts to all of the infarct a rteries. The LPs persisted in 8, who received no graft to the infarct artery. One week after CABG, the LPs were still present in 4, all of w hom had no graft to the infarct right coronary artery. Conclusions. In patients with positive LPs late after myocardial infarction, grafting to the infarct artery eliminated the LPs soon after CABG.