Acute Microvascular Impairment Post-Reperfused STEMI Is Reversible and Has Additional Clinical Predictive Value: A CMR OxAMI Study

JACC Cardiovasc Imaging. 2019 Sep;12(9):1783-1793. doi: 10.1016/j.jcmg.2018.10.028. Epub 2019 Jan 16.


Objectives: This study sought to investigate the clinical utility and the predictive relevance of absolute rest myocardial blood flow (MBF) by cardiac magnetic resonance (CMR) in acute myocardial infarction.

Background: Microvascular obstruction (MVO) remains one of the worst prognostic factors in patients with reperfused ST-segment elevation myocardial infarction (STEMI). Clinical trials have focused on cardioprotective strategies to maintain microvascular functionality, but there is a need for a noninvasive test to determine their efficacy.

Methods: A total of 64 STEMI patients post-primary percutaneous coronary intervention underwent 3-T CMR scans acutely and at 6 months (6M). The protocol included cine function, T2-weighted edema imaging, pre-contrast T1 mapping, rest first-pass perfusion, and late gadolinium enhancement imaging. Segmental MBF, corrected for rate pressure product (MBFcor), was quantified in remote, edematous, and infarcted myocardium.

Results: Acute MBFcor was significantly reduced in infarcted myocardium compared with remote MBF (MBFinfarct 0.76 ± 0.20 ml/min/g vs. MBFremote 1.02 ± 0.21 ml/min/g, p < 0.001), but it significantly increased at 6M (MBFinfarct 0.76 ± 0.20 ml/min/g acute vs. 0.85 ± 0.22 ml/min/g at 6M, p < 0.001). On a segmental basis, acute MBFcor had incremental prognostic value for infarct size at 6M (odds of no LGE at 6M increased by 1.4:1 [p < 0.001] for each 0.1 ml/min/g increase of acute MBFcor) and functional recovery (odds of wall thickening >45% at 6M increased by 1.38:1 [p < 0.001] for each 0.1 ml/min/g increase of acute MBFcor). In subjects with coronary flow reserve >2 or index of myocardial resistance <40, acute MBF was associated with long-term functional recovery and was an independent predictor of infarct size reduction.

Conclusions: Acute MBF by CMR could represent a novel quantitative imaging biomarker of microvascular reversibility, and it could be used to identify patients who may benefit from more intensive or novel therapies.

Keywords: acute myocardial infarction; magnetic resonance; myocardial blood flow.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Contrast Media / administration & dosage
  • Coronary Circulation*
  • Female
  • Humans
  • Magnetic Resonance Imaging, Cine*
  • Male
  • Meglumine / administration & dosage
  • Microcirculation*
  • Middle Aged
  • Myocardial Perfusion Imaging / methods*
  • Organometallic Compounds / administration & dosage
  • Percutaneous Coronary Intervention / adverse effects*
  • Predictive Value of Tests
  • Prospective Studies
  • Recovery of Function
  • ST Elevation Myocardial Infarction / diagnostic imaging
  • ST Elevation Myocardial Infarction / physiopathology
  • ST Elevation Myocardial Infarction / therapy*
  • Time Factors
  • Treatment Outcome


  • Contrast Media
  • Organometallic Compounds
  • Meglumine
  • gadoterate meglumine