The prognostic significance of microvascular obstruction after myocardial infarction as defined by cardiovascular magnetic resonance

Abstract

This editorial refers to ‘Sequelae of acute myocardial infarction regarding cardiac structure and function and their prognostic significance as assessed by magnetic resonance imaging’† by V. Hombach et al. , on page 549 Cardiac magnetic resonance imaging (CMR) has evolved into an important imaging tool in the assessment of patients with myocardial infarction (MI), with or without reperfusion. CMR is a gold standard technique for measuring left ventricular volumes and global function.1 The technique of delayed contrast enhancement has been carefully validated in animal markers as a measure of infarct size.2 The presence of hypo-enhanced regions at the core of hyper-enhanced infarctions is a marker of microvascular obstruction (MO)3 and a predictor of lack of functional recovery in the infarct zone4 and poor cardiovascular outcome in the patient post-MI.5 The paper by Hombach et al. 6 is the largest report to date of these CMR techniques used in sequential fashion in patients with acute MI and thus is quite instructive regarding prognostic factors derived from CMR. These authors studied 110 patients at a mean of day 6 after acute MI, which is a relatively late initial time point as patients currently are typically discharged before day 6. Of the original 110 patients, 89 returned for follow-up imaging at an average of ∼9 months after MI. The remainder died ( n =7), refused follow-up ( n =11), or had … *Corresponding author. Tel: 434 243 6060; fax: 434 982 1618. E-mail address : ckramer{at}virginia.edu