Classification of MI

Myocardial infarction is most often categorized by size and location. An infarction can further be classified based on several other clinical factors.


From an anatomic perspective, the two types of MI are transmural and nontransmural.


  • A transmural MI is characterised by ischaemic necrosis of the full thickness of the affected muscle segment(s), extending from the endocardium through the myocardium to the epicardium.
  • A nontransmural MI is defined as an area of ischaemic necrosis that does not extend through the full thickness of myocardial wall segment(s) but is limited either to the endocardium or to the endocardium and the myocardium.


The endocardial and subendocardial zones of the myocardial wall are the least perfused regions of the heart and are most vulnerable to conditions of ischaemia.

Anterior Myocardial Infarction



Lateral Myocardial Infarction


Septal Myocardial Infarction


Inferior Myocardial Infarction


The task force consisting of the American College of Cardiology Foundation, the American Heart Association, the European Society of Cardiology and the World Heart Federation have developed universal classification criteria based on clinical findings.1

Overview of the clinical classification of MI1

Overview of the clinical classification of MI based on clinical findings

Description of the clinical classification of MI1

Detailed definition of different types of clinically classified MI

  1. Thygesen K, et al. Universal definition of myocardial infarction. J Am Coll Cardiol 2012;60(16):1581-1598.