Microvascular Obstruction and Intramyocardial Hemorrhage in Reperfused Myocardial Infarctions: Pathophysiology and Clinical Insights From Imaging

JACC Cardiovasc Imaging. 2024 Jul;17(7):795-810. doi: 10.1016/j.jcmg.2024.02.003. Epub 2024 Apr 10.

Abstract

Microvascular injury immediately following reperfusion therapy in acute myocardial infarction (MI) has emerged as a driving force behind major adverse cardiovascular events in the postinfarction period. Although postmortem investigations and animal models have aided in developing early understanding of microvascular injury following reperfusion, imaging, particularly serial noninvasive imaging, has played a central role in cultivating critical knowledge of progressive damage to the myocardium from the onset of microvascular injury to months and years after in acute MI patients. This review summarizes the pathophysiological features of microvascular injury and downstream consequences, and the contributions noninvasive imaging has imparted in the development of this understanding. It also highlights the interventional trials that aim to mitigate the adverse consequences of microvascular injury based on imaging, identifies potential future directions of investigations to enable improved detection of disease, and demonstrates how imaging stands to play a major role in the development of novel therapies for improved management of acute MI patients.

Keywords: cardiac imaging; intramyocardial hemorrhage; microvascular obstruction; reperfused MI.

Publication types

  • Review

MeSH terms

  • Animals
  • Coronary Circulation*
  • Coronary Vessels / diagnostic imaging
  • Coronary Vessels / physiopathology
  • Hemorrhage* / diagnostic imaging
  • Hemorrhage* / etiology
  • Hemorrhage* / physiopathology
  • Hemorrhage* / therapy
  • Humans
  • Microcirculation*
  • Microvessels / diagnostic imaging
  • Microvessels / physiopathology
  • Myocardial Infarction* / complications
  • Myocardial Infarction* / diagnostic imaging
  • Myocardial Infarction* / physiopathology
  • Myocardial Infarction* / therapy
  • Myocardial Reperfusion
  • Myocardial Reperfusion Injury / diagnostic imaging
  • Myocardial Reperfusion Injury / etiology
  • Myocardial Reperfusion Injury / physiopathology
  • Myocardium* / pathology
  • Predictive Value of Tests*
  • Prognosis
  • Risk Factors
  • Treatment Outcome