Subendocardial Fat in Myocardial Infarction

Fig: Axial contrast-enhanced CT image shows a curvilinear low attenuation in the subendocardial portion of the left anterior descending (LAD) coronary artery territory of the left ventricle. The patient had a history of remote myocardial infarction (MI).

Myocardial Fat

• Common entity, found histologically in 68% of ischemic heart disease patients and 84% of patients with history of MI.
• May result from inability of ischemic myocytes to metabolize fatty acids.
  
• Can be shown on cardiac MRI and CT.
• In one study, it was detected in 22% of cases and it was most commonly seen in LAD territory.
  

What does it mean?

• It is associated with greater infarct age
• Patients with myocardial fat had more severe regional wall motion abnormalities on echocardiography

Reference:
Ahn SS, et al. CT detection of subendocardial fat in myocardial infarction. AJR 2009;192:532-537.