Microcirculatory dysfunction in ST-elevation myocardial infarction: cause, consequence, or both?

AIMS: Despite advancements over the past years, normal reperfusion at the myocardial level is not achieved in approximately every other patient with ST-elevation myocardial infarction. In the current work, we aimed at reviewing the role of the coronary microcirculation in the development and outcome of this acute coronary syndrome entity. METHODS AND RESULTS: A PubMed/Medline search was performed with the key words acute coronary syndrome, acute myocardial infarction, coronary artery disease, endothelial dysfunction, microcirculation, and reperfusion. The synthesis of the information points to myocardial microcirculatory dysfunction as a consequence of a primary epicardial event, based on the vulnerable plaque concept. As an alternative theory, microcirculatory dysfunction may contribute to the clinical course of the acute coronary event, based on the vulnerable patient concept. The pros and cons of these two viewpoints are to be discussed and their influence on patient management is to be considered. CONCLUSION: Microcirculatory dysfunction in ST-elevation myocardial infarction can be cause, consequence or both according to non-traditional and traditional concepts.