Table 1.

Comparison between conditions that may lead to regional myocardial dysfunction

	Nontransmural Myocardial Infarction	Transmural Myocardial Infarction	Stunned myocardium	Hibernated myocardium	Post-infarction remodeling	Nonischemic cardiomyopathies
Perfusion	Normal or reduced depending on the existence or not of adequate reperfusion or microvascular obstruction	Normal or reduced depending on the existence or not of adequate reperfusion or microvascular obstruction	Normal by definition	Reduced by definition	Normal	Normal
Function	Normal	Reduced	Reduced but reversible with perfusion restoration (hours or weeks)	Reduced but reversible with perfusion restoration (may take months to recover)	Reduced	Normal or reduced(depending on the percentage of the affected area)
Metabolism	Normal or reduced (low FDG uptake)	Reduced (low FDG uptake)	Not reduced (high FDG uptake)	Not reduced (high FDG uptake, perfusion-metabolism mismatch)	Probably normal	Normal or reduced (low FDG uptake)
Histology	Replacement fibrosis	Replacement fibrosis	Normal myocytes	May be normal or present a certain degree of differentiation of the myocytes, with loss and disorganization of cellular elements	Hypertrophy, dilation, and architectural distortion of myocardial fibers	Replacement fibrosis
Delayed Enhancement	Delayed enhancement in the subendocardium (< 50% of the area of the segment). Usually in a coronary territory, unless it has multiple infarctions or the patient has undergone surgery with graft placement	Transmural delayed enhancement that may compromise from the subendocardium to the epicardium (> 50% of the area of the segment). Usually in a coronary territory, unless it has multiple infarctions or the patient has undergone surgery with graft placement	Normal, unless there is a combination of stunned myocardium and myocardial infarction	Normal, unless there is a combination of hibernated myocardium and myocardial infarction	Negative (myocardial dysfunction remote to a large infarction) and, therefore, viable.	Variable, best identified as mesocardial, epicardial, diffuse, or even negative

Table modified from Arai.⁷