Two-dimensional echocardiographic findings of cardiovascular involvement by invasive thymoma

Pericardial involvement by thymomas. Entirely intrapericardial thymoma and a pericardial metastasis of thymoma with glomeruloid vascular proliferations

Thymomas are usually found in the anterior mediastinum, the normal location of the thymus. Involvement of the pericardium by thymic tumors is seen in invasive or metastasized thymoma. Very rarely, thymomas arise primarily in the pericardium. These tumors are believed to derive from thymic tissue which was misplaced in the pericardium during embryologic development. In contrast to patients with orthotopic thymoma who commonly suffer from paraneoplastic diseases, especially myasthenia gravis, patients with intrapericardial thymoma manifestations mainly have symptoms of congestive heart failure which are caused by local complications of tumor growth. In this study, we present two cases of thymoma involving the pericardium. Both tumors were polygonal-oval cell thymomas. In one of the cases diagnosis of an entirely intrapericardial thymoma was established by autopsy. In the other case, explorative thoracotomy revealed massive pericardial and pleural tumor manifestations. The latter tumor showed a peculiar histological pattern with multiple glomeruloid bodies, a finding reported only once for thymomas.

Echocardiographic manifestations of mediastinal masses compressing or encroaching on the heart

Because of its central position within the thorax, the heart can be encroached upon by masses originating in either anterior, posterior, or superior mediastinum. A distinction may be made between (A) Encroachment: distortion or partial displacement of one or more cardiac chambers by a contiguous mediastinal mass, without adverse hemodynamic effects, and (B) Compression: resulting in clinical manifestations similar to tamponade. Transthoracic and, recently, transesophageal echocardiography have been found useful in detecting mediastinal masses, the information obtained being complementary or preliminary to more complete imaging by CT or MRI. Anterior masses tend to compress the right heart chambers; posterior masses impinge on or compress the left atrium or ventricle, particularly the former. The wide variety of echographic appearances are briefly reviewed. Recently TEE has made it possible to diagnose masses obstructing the superior vena cava or pulmonary veins. A common, though little known, type of posterior mediastinal encroachment that echocardiographers need to be aware of is that of abnormal esophageal/gastric masses including hiatus hernia and esophageal carcinoma, which have typical two-dimensional echo features and may sometimes simulate left atrial masses.

The value of two-dimensional echocardiography in detecting malignant tumors in the heart

Six unusual cases of tumor involvement of the heart and pericardium, diagnosed antemortem by two-dimensional echocardiography (2DE), are described. The tumors consisted one each of sacral chordoma, mediastinal seminoma, leiomyosarcoma of the uterus, osteosarcoma, invasive thymoma, and lung cancer. The current study again recognizes the concept that any type of malignant tumor has a possibility of involving the heart. If cardiac involvement is suspected, 2DE examination should be performed in patients with any kind of malignant tumor. The information obtained not only provides guidance for therapeutic maneuvers, but also is beneficial for follow-up observation of the patients and assessment of the therapy.