Entrapped Coronary Arteries in Constrictive Pericarditis.

Pericardial constriction can be present without pericardial calcium and often without pericardial thickening. This epicardial coronary artery motion abnormality due to entrapment in a thickened, fibrotic pericardium, is characteristic of constrictive pericarditis, and differentiates this entity from other close differential diagnoses, such as restrictive and dilated cardiomyopathy.