Transient ST-elevation myocardial infarction: clinical course with intense medical therapy and early invasive...

Patients presenting with ST-elevation myocardial infarction (STEMI), whose symptoms and electrocardiographic changes completely resolve upon admission and before the administration of reperfusion therapy, pose a therapeutic dilemma. The optimal management of this syndrome, termed here as transient STEMI (TSTEMI), has not yet been fully determined. We describe 69 prospectively recorded patients with TSTEMI, of which 63 patients (56.7 +/- 11 years, 48 men) were available for long-term follow-up out of 1244 consecutive patients with acute myocardial infarction (5%). Patients with TSTEMI treated with intravenous isosorbide dinitrate, aspirin, and clopidogrel, and/or with glycoprotein IIb/IIIa inhibitors were compared with a control group of matched patients with STEMI without resolution, who were treated conventionally. The time interval from symptom onset to presentation at the emergency department of patients with TSTEMI was 1.7 +/- 1.3 hours, and to first recording of ST elevations, 1.5 +/- 1.4 hours. Symptoms and electrocardiographic changes fully resolved 1.2 +/- 0.8 hours later, 1 hour after aspirin and nitrate administration. Coronary angiography, performed 36 +/- 39 hours (median, 24 hours) from admission, demonstrated no obstructive lesion or single-vessel obstructive disease in 43 patients (70%). Primary coronary intervention was performed in 48 patients (77%), and 8 patients (13%) were referred to surgery. Left ventricular ejection fraction was within normal limits, and peak creatine kinase was mildly elevated. Patients with TSTEMI had less extensive coronary artery disease (P < .038), better thrombolysis in myocardial infarction flow on angiography (P < .01), lower peak creatine kinase level (P < .001), higher left ventricular ejection fraction (P < .0001), and lower likelihood to sustain a second additional coronary event after index admission (P = .024) than patients with STEMI. Transient STEMI was associated with less myocardial damage, less extensive coronary artery disease, higher thrombolysis in myocardial infarction flow grade in culprit artery, and better cardiac function. These data suggest that immediate intense medical therapy with an early invasive approach is an appropriate therapy in patients with TSTEMI.