Two patients with primary angiosarcoma of the heart were treated. The first patient presented with spinal cord compression syndrome secondary to metastatic angiosarcoma of the lumbar spine. The primary tumour was found to be a right atrial mass. In contrast, the second patient presented with repeated episodes of pleural and pericardial hemorrhage resulting in effusive constrictive pericardial physiology. Repeated diagnostic attempts failed, and an open thoracotomy found an infiltrative type of pericardial angiosarcoma involving the right atrial wall. For both patients, the angiosarcoma proved to be rapidly fatal. The clinical spectrum of these two cases and a review of the literature suggest two major clinicopathological forms most commonly arising from the right atrium: a large obstructing mass and a less common, less symptomatic, locally infiltrative tumour, offering a greater diagnostic challenge. The prognosis is usually poor. However, a more aggressive diagnostic approach -- especially in the locally infiltrative tumours -- may offer hope for improving survival.