PRIMARY MYOCARDIAL FIBROMAS: REPORT OF 2 CASES.

Abstract

Primary cardiac tumors, though uncommon, are not as rare as one might think. The recent literature contains several excellent review articles that classify and tabulate the various types of primary benign and malignant cardiac tumors (1, 7, 8, 10, 13). This communication presents 2 cases of primary benign cardiac tumors, i.e., myocardial fibromas. In these the x-ray examination showed an unusual pattern of calcification within the tumor. This has not been described in other case reports of cardiac fibromas or other primary cardiac tumors (5, 12, 16, 17). In earlier literature the term fibroma referred to papillary tumors of the cardiac valves. As described by Yater and Hertzog (1, 2), these were essentially fibrous papillomatous growths with an endothelia covering arising from the surface of a valve. Prichard, in his excellent review article (7), pointed out the difficulty of classification in regard to fibromas versus hamartomas, but he also considered fibromas papillary fibrous tumors arising from heart valves. More recently, fibroma has been used to describe a fibrous neoplasm sometimes called fibrous hamartoma, a nonencapsulated but well demarcated intramyocardial lesion which appears very similar to a leiomyoma in gross (9). They are most common in the first few years of life and most often primary in the left ventricular wall or intraventricular septum (5, 12, 16, 17). Neither the reviews nor the case reports, however, described calcification within the tumor mass. Central and peripheral calcification is seen frequently in myxomas, the most common primary cardiac tumors, and almost always in intracavitary polypoid tumors in the atria (7). Case Reports Two cases of primary benign cardiac tumors are described. The pathologic diagnosis in each case was confirmed by the Armed Forces Institute of Pathology. Case I. This 17-month-old white male was the product of a normal pregnancy but was delivered by cesarean section because of abnormal third trimester vaginal bleeding in the mother. During the first month of life the infant was normal, but from one to four months of age he suffered severe respiratory infection with congestive heart failure and cyanosis. This responded to digitalization. The patient did well until the age of sixteen months when he was seen for pneumonia. Chest radiographs were abnormal, with a homogeneous density in the left lower lobe confluent with the heart shadow. Diagnosis by the referring physician was cyst of the lung, possibly dermoid cyst, and the infant was referred to Wilford Hall USAF Hospital. Admission examination revealed a normally developed child in no acute distress. The pulse was 120 and regular. Oily skin and a fine scaly erythematous rash were present. Respiration was labored with left lower lobe râles. Sinus rhythm was normal without murmurs. The liver was palpable 2 finger-breadths below the right costal margin.