A rare disease of primary cardiac intimal sarcoma at the left atrium presented with mimicking mitral stenosis in a patient with polycystic kidney disease

Left ventricular intimal sarcoma: a case report

Background

Secondary cardiac tumours are much more common compared with primary (100-1000 times). The majority of the primary cardiac tumours are benign; however, almost a quarter are malignant, and 95% of these are sarcomas. The rarest type of primary malignant cardiac sarcoma is intimal (spindle cell) sarcoma.

Case summary

A 37-year-old woman presented with episodes of breathlessness. Initially treated for a chest infection, however, the patient continued to deteriorate and presented to the emergency department. A large pericardial effusion was discovered and drained, with samples sent for analysis. A repeat interval echo confirmed the resolution of the pericardial effusion with preserved left ventricular (LV) systolic function. The computed tomography (CT) of the thorax showed suspicious lesions in the heart and lung while the repeat echo raised suspicion of an infiltrative disease. A cardiac magnetic resonance imaging scan was performed, which suggested evidence of an undifferentiated sarcoma involving the posterior wall of the LV and an overlying thrombus. Computed tomography of the abdomen and pelvis did not show any evidence of abdominal metastasis. A CT-guided lung biopsy was arranged. On histological analysis, the report was overall strongly supportive of a diagnosis of intimal sarcoma. She underwent chemotherapy until recently.

Discussion

Cardiac intimal sarcomas are the least reported type of primary malignant tumours of the heart. They are encountered more commonly in the large arterial blood vessels, including the pulmonary artery and aorta, and are extremely rare in the heart. A prompt diagnosis is essential as they are considered extremely aggressive.

[Pathology of primary cardiac tumors]

Primary heart neoplasms are rare and poorly known by general pathologists. However, they are not exceptionally encountered in pathology laboratories having a recruitment of cardiac surgery specimens. About 80 % of them are benign tumors and 20 % are malignant tumors. Some tumors are specific to the heart or have characteristics when they grow in the heart, including myxoma and papillary fibroelastoma. The classification currently in use is the 4th edition of the WHO classification of heart tumors published in 2015, which takes into account the evolution of knowledge in the field of sarcomas, but which does not yet recognize cardiac intimal sarcoma. recently individualized in its intracardiac location.