Early identification of impaired myocardial reperfusion with serial assessment of ST segments after percutaneous transluminal coronary angioplasty during acute myocardial infarction

To evaluate the relation between ST-segment analysis and microvascular reperfusion in patients with acute myocardial infarction (AMI), we studied 51 patients with first AMI who were successfully treated by percutaneous transluminal coronary angioplasty (PTCA). The lead showing the greatest ST-segment elevation on the 12-lead electrocardiogram (ECG) was serially investigated until 24 hours after PTCA. Successful reperfusion was determined by technetium-99m tetrofosmin single-photon emission computed tomography. Impaired reperfusion (group 1: 0 mm change in ST segment from before to 30 minutes after PTCA >0) were in group 1, whereas 23 of 37 patients (62%) with ST-segment resolution (ΔST ≤0) were in group 2. The sensitivity and specificity of persistent ST-segment elevation for predicting impaired microvascular reperfusion were 42% and 85%, respectively. Thus, persistent ST-segment elevation 30 minutes after primary PTCA was a highly specific electrocardiographic marker of impaired reperfusion in patients with AMI.