Myocarditis and myocardial interstitial fibrosis in constrictive pericarditis--an extended pathological spectrum?

We performed endomyocardial biopsy in six patients with constrictive pericarditis, revealing the presence of myocarditis and myocardial interstitial fibrosis in all regardless of the endocardial thickening. These findings suggest that the presence of endomyocardial involvement in the setting of restrictive heart disease should not be deemed specific for endomyocardial fibrosis when the clinical evaluation suggests constrictive pericarditis.