Primary tumours are exceedingly rare in the heart. According to Berthenson the structure in 30 published cases of primary tumours of the heart was as follows: - Sarcoma 9 (Pure Sarcoma 5, Fibrosarcoma 3, Myxosarcoma 1); Myxoma 7 (Pure Myxoma 4, Fibro-myxoma 3); Fibroma 6; Syphilitic tumours 2: Cancer 3; Fatty tumour 2; Cyst 1.
Secondary tumours are also rare. Sarcomas occurring in the neighbourhood may spread to the heart, and especially those of the mediastinum, involving first the parietal and then the visceral pericardium. Sometimes also a Cancer of the oesophagus extends to the pericardium. Cancers when they become generalized sometimes occur in the heart, in the form of round pale tumours.
Of Parasites, the echinococcus and the cysticerus cellulosae have been found in the heart. The cysticercus of the taenia solium is-frequent in the heart of swine, and that of the taenia mediocanellata in cattle, but they are very rare in man.
Berthenson, Virch. Arch., cxxxii., 390; Fraentzel, Vorles. uber die Krankh. des Herzens, 1891.