[Restrictive cardiomyopathy versus constrictive pericarditis in patients with diastolic dysfunction: MR imaging features]

Restrictive cardiomyopathies are characterized by diastolic dysfunction while systolic function is usually preserved. MRI is helpful by its ability to characterize tissues, especially the demonstration of interstitial or nodular fibrosis based on the underlying etiology. In the presence of constrictive pericarditis from pericardial inflammation, fibrosis or calcifications, diastolic expansion is impaired resulting in poor diastolic ventricular filling, resulting in a characteristic type of diastolic impairment, adiastole. MRI can demonstrate the underlying anatomical lesion: pericardial thickening, though the presence of a pericardium or normal thickness does not entirely exclude the possibility of constriction. As such, the presence of additional imaging features such as abnormal right ventricular shape, vena cava dilatation, and paradoxical movement of the intraventricular septum, during operator-guided deep respiration.