Effect of delayed recanalization of occluded acute myocardial infarction-related artery using coronary angioplasty on late potentials

Abstract

Recent evidence suggests that late reperfusion of an occluded infarct-related artery (IRA) after acute myocardial acute infarction (MAI), may reduce the frecuency of subsequent arrhythmic events and sudden death. Mechanical reperfusion of an occluded IRA, performing percutaneous trasluminal coronary angioplasty (PTCA) 48 to 2 weeks after MAI, has a big success rate, and low symptomatic restenosis. Twenty subjects (19 men and 1 women, aged 32 to 77 year) with a first MAI, signal-averaged electrocardiographic (SAECG), and an occluded IRA were prospectively identified. Late potentials were present in 14 patients after MAI. Eighteenth had a successful PTCA of the occluded IRA, 6 to 32 days after MAI. Follow-up SAECG was performed 1 to 8 days later. In the subgroup of 12 patients with successful reperfusion with an abnormal SAECG before PTCS, 7 (58,3%) showed resolution of late potentials at follow-up, the filtered QRS duration showed a significant reduction (112,1 ± 14,2 msec to 96,7 ± 12,6 msec, p=0,02), and there was a tendency for the root-mean-square voltage to increase and the duration of low amplitude signals < 40 µV to decrease after angioplasty. In contrast 2 patients with late potentials before PTCA and usuccessful reperfusion of the culprit vessel way reduce the incidence of abnormalities on the SAECG, if thhis will result in improved longterm survival awaits confirmations in a large trial.