Background: Metastatic tumors of the heart are 20 to 40 times more common than primary tumors. Metastases originate mainly in carcinomas and melanomas, the latter having the greatest propensity for cardiac involvement. On rare occasions this type of tumor may first manifest itself as a cardiac metastasis.
Methods: The authors present clinical, laboratory and imaging data from a patient with a cardiac mass that was the first manifestation of a melanoma. No other tumor location was detected by imaging studies.
Results: The patient presented with exertional dyspnea and tachycardia and was found to have a large mass in the right atrium. He underwent surgical removal of the tumor, but curative excision was not possible. A diagnosis of cardiac metastasis from malignant melanoma was made. The patient died soon afterwards from disseminated metastatic disease.
Conclusions: This case represents a rare manifestation of melanoma located in the right atrium, with unknown origin of the primary tumor. Although surgery may be useful to palliate symptoms and improve survival in certain patients, it may also be associated with dissemination of the disease.