Cardiac Outpouchings: Definitions, Differential Diagnosis, and Therapeutic Approach

Table 1

Characterizing features of cardiac outpouchings.

Cardiac outpouching features	Aneurysm	Pseudoaneurysm	Diverticulum	Herniation
Common anatomic location	Cardiac apex; LV anterior wall	LV posterior wall	Cardiac apex (apical); LV anterior wall; subaortic (nonapical)	Variable
Neck	Wide	Narrow	Variable	Variable
Neck/chamber ratio	0.9–1.0	0.25–0.5	Variable	Variable
Contractility	Dyskinesia	Akinesia	Synchronous	Synchronous
MRI appearance	Delayed enhancement of the myocardial wall	Delayed enhancement of the overlying pericardium	Normal myocardial and pericardial signal intensity	Normal myocardial signal intensity and discontinuity of overlying pericardium
Histology	Fibrous tissue interposed to spared myocardium	Pericardium with mural thrombus	Endocardium, myocardium, and pericardium	Endocardium and myocardium

LV: left ventricle; MRI: magnetic resonance imaging.