Metastatic involvement of the heart and pericardium: CT and MR imaging

Metastases to the heart and pericardium are much more common than primary c ardiac tumors and are generally associated with a poor prognosis. Tumors th at are most likely to involve the heart and pericardium include cancers of the lung and breast, melanoma, and lymphoma. Tumor may involve the heart an d pericardium by one of four pathways: retrograde lymphatic extension, hema togenous spread, direct contiguous extension, or transvenous extension. Met astatic involvement of the heart and pericardium. may go unrecognized until autopsy. Impairment of cardiac function occurs in approximately 30% of pat ients and is usually attributable to pericardial effusion. The clinical pre sentation includes shortness of breath, which may be out of proportion to r adiographic findings in patients with pericardial effusion or may be the re sult of associated pleural effusion. Patients may also present with cough, anterior thoracic pain, pleuritic chest pain, or peripheral edema. The diff erential diagnosis of pericardial effusion in a patient with known malignan cy includes malignant pericardial effusion, radiation-induced pericarditis, drug-induced pericarditis, and idiopathic pericarditis. Any disease proces s that causes thickening or nodularity of the pericardium or myocardium or masses within the cardiac chambers can mimic metastatic disease.