Right-heart overload happens relatively rarely in sarcoidosis, even with fibroemphysematous changes. Of 21 cases that we studied, six (28%) had clinical and/or electrocardiographic features of cor pulmonale. The cause of cor pulmonale often evoked is an invasion of the walls of pulmonary vessels by sarcoid granulomas or their compression by the fibrotic process. Pathological studies in one patient showed compression of large pulmonary arteries associated with specific sarcoid lesions in small small and medium-sized arteries.