Incidence and Significance of Spontaneous ST Segment Re-elevation After Reperfused Anterior Acute Myocardial Infarction　― Relationship With Infarct Size, Adverse Remodeling, and Events at 1 Year―

Abstract

Background:Up to 25% of patients with ST elevation myocardial infarction (STEMI) have ST segment re-elevation after initial regression post-reperfusion and there are few data regarding its prognostic significance.

Methods and Results:A standard 12-lead electrocardiogram (ECG) was recorded in 662 patients with anterior STEMI referred for primary percutaneous coronary intervention (PPCI). ECGs were recorded 60–90 min after PPCI and at discharge. ST segment re-elevation was defined as a ≥0.1-mV increase in STMax between the post-PPCI and discharge ECGs. Infarct size (assessed as creatine kinase [CK] peak), echocardiography at baseline and follow-up, and all-cause death and heart failure events at 1 year were assessed. In all, 128 patients (19%) had ST segment re-elevation. There was no difference between patients with and without re-elevation in infarct size (CK peak [mean±SD] 4,231±2,656 vs. 3,993±2,819 IU/L; P=0.402), left ventricular (LV) ejection fraction (50.7±11.6% vs. 52.2±10.8%; P=0.186), LV adverse remodeling (20.1±38.9% vs. 18.3±30.9%; P=0.631), or all-cause mortality and heart failure events (22 [19.8%] vs. 106 [19.2%]; P=0.887) at 1 year.

Conclusions:Among anterior STEMI patients treated by PPCI, ST segment re-elevation was present in 19% and was not associated with increased infarct size or major adverse events at 1 year.