Risk stratification by cardiac magnetic resonance imaging after ST-elevation myocardial infarction.

Abstract

This review summarizes the currently available evidence for the use of cardiac magnetic resonance (CMR) imaging for risk stratifying patients after ST-elevation myocardial infarction (STEMI). Growing evidence indicates that CMR imaging allows a comprehensive prognosis assessment in patients following STEMI. Multiple trials have shown that markers of cardiac dysfunction, especially left ventricular ejection fraction, are strongly predictive for clinical events beyond traditional risk factors. Recent data indicate that CMR can be an even more specific marker for the prediction of clinical prognosis by determining the extent of irreversible myocardial and microvascular damage for an individual patient. A multiparametric approach by CMR for optimized risk stratification allows exact infarct sizing and tissue characterization of the jeopardized and infarcted myocardium including microvascular injury. Many of these CMR parameters (infarct size, myocardial salvage, microvascular obstruction, intramyocardial hemorrhage) have demonstrated an incremental prognostic value in addition to clinical risk factors and left ventricular ejection fraction. The comprehensive evaluation of STEMI patients by CMR imaging has the potential to provide incremental prognostic information for risk stratification beyond established clinical risk markers. In light of the lack of trials, however, designed to prospectively test the value of a CMR-guided therapeutic strategy in patients with STEMI, the use of CMR for risk stratification of the postinfarction patient awaits further validation and research.