Prognostic value of persistent ST-segment elevation after successful primary angioplasty

Introduction and objectives. A variable percentage of patients with myocardial infarction treated with successful primary angioplasty and restoration of coronary flow show persistent ST-segment elevation, probably due to inadequate cellular reperfusion. We studied if persistent STsegment elevation was a predictor of worse prognosis. Patients and method. We comparatively studied the clinical and angiographic results of 116 acute myocardial infarction patients after successful primary angioplasty, which were classified into two groups depending on the persistence (> 50%) or reduction (less than or equal to 50%) of ST-segment elevation between the electrocardiograms recorded before and after coronary angioplasty. Results. In 96 patients (Group I) the ST-segment elevation improved after angioplasty and in 20 patients (Group II) there was no improvement. Baseline characteristics were similar in both groups except for Killip class 4, which was more prevalent in group II (7.2 vs. 25%; p, = 0.01). There were no differences in the characteristics or results of the procedure. There was more myocardial damage in group II (CK 3,149 +/- 1,636 vs. 2,185 +/- 2,010 U/I; p = 0.02), associated with a more impaired left ventricular ejection fraction in the late angiographic control (47 16 vs 55 +/- 16%; p = 0.05). At a one-year follow-up the mortality was 8.3% in group I and 30% in group II (p = 0.01). Conclusions. The persistence of ST-segment elevation after successful primary angioplasty identifies a group of patients that may suffer an increased risk of adverse events in spite of good epicardial flow.