Current myocardial infarction classification does not predict risks of early revascularization.

Background: Compared with non-ST-elevation myocardial infarction (MI), ST-elevation MI has been associated with increased mortality after medical treatment and percutaneous coronary intervention. Our study investigated the prognostic value of MI classification in the setting of surgical revascularization within 21 days of MI.

Methods: We studied 2412 consecutive patients between 1995 and 2007 who underwent an isolated coronary artery bypass grafting procedure within 21 days after MI. The outcomes of interest were in-hospital mortality and major adverse events, which included death, MI, stroke, and renal failure requiring hemodialysis.

Results: Rates of crude in-hospital mortality and major adverse events were higher in ST-elevation MI patients. Stepwise regression analysis suggested that MI subtype (ST-elevation MI vs non-ST-elevation MI) did not predict in-hospital mortality or major adverse events. A secondary analysis using propensity score matching showed similar surgical outcomes between the two cohorts.

Conclusions: Surgical risks of patients with recent MI are independent of MI subtype. Distinguishing ST-elevation MI and non-ST-elevation MI is of limited value in the decision-making process of early surgical intervention.