cardiovascular disorders
Cardiac Tumors
Classification of Cardiac Tumors
Some of the more common primary and secondary cardiac tumors are listed (see Types of Cardiac Tumors ). Primary cardiac tumors may be Benign (nearly 80% of cases) Malignant (the remaining 20%) Examples are myxomas, papillary fibroelastomas, rhabdomyomas, fibromas, hemangiomas, teratomas, lipomas, paragangliomas, and pericardial cysts. Myxomais most common, accounting for 50% of all primary cardiac tumors. Incidence in women is 2 to 4 times that in men. In uncommon familial forms (Carney complex), men are affected more often. About 75% of myxomas occur in the left atrium, and the rest occur in the other chambers as a solitary tumor or, less commonly, at several sites. Myxomas may be up to 15 cm in diameter. About 75% are pedunculated and may prolapse through the mitral valve and obstruct ventricular filling during diastole. The remainder of the tumors are broad-based and sessile. Myxomas may be myxoid and gelatinous; smooth, firm, and lobular; or friable and irregular. Friable, irregular myxomas increase risk of systemic embolism. Carney complex is a familial, autosomal dominant syndrome of recurrent cardiac myxomas with some combination of cutaneous myxomas, myxoid mammary fibroadenomas, pigmented skin lesions (lentigines, ephelides, blue nevi), Overview of Multiple Endocrine Neoplasias (MEN) (primary pigmented nodular adrenocortical disease causing Papillary fibroelastomasare avascular papillomas that occur on heart valves in > 80% of cases. The papillomas are more likely to occur on the left side of the heart ), predominantly on the aortic and mitral valves. Men and women are affected equally. They have papillary fronds branching from a central core, resembling sea anemones. About 45% are pedunculated. They do not cause valvular dysfunction but increase risk of embolism. affect mainly infants and children, 80% of whom also have Tuberous Sclerosis Complex (TSC) . Rhabdomyomas are usually multiple and located intramurally in the septum or free wall of the left ventricle, where they affect the cardiac conduction system. They are firm, white lobules that typically regress with age. A minority of patients develop tachyarrhythmias and Fibromasoccur mainly in children and are associated with adenoma sebaceum of the skin and kidney tumors. They occur primarily on the left side of the heart, are often located within the ventricular myocardium, and may develop in response to inflammation. They can compress or invade the cardiac conduction system, causing arrhythmias and sudden death. Some fibromas occur as part of a syndrome with generalized body overgrowth, jaw keratocytes, skeletal abnormalities, and various benign and malignant tumors (Gorlin, or basal cell nevus syndrome). Hemangiomascause symptoms in a minority of patients. Most often, they are incidentally detected during examinations done for other reasons. Teratomasof the pericardium affect mainly infants and children. They are often attached to the base of the great vessels. About 90% are located in the anterior mediastinum; the rest, mainly in the posterior mediastinum. can develop at a wide range of ages. They originate in the endocardium or epicardium and have a large pedunculated base. Many are asymptomatic, but some obstruct flow or cause Overview of Arrhythmias . including Pheochromocytoma , rarely occur in the heart; when they do, they are usually localized to the base of the heart near vagus nerve endings. They may manifest with symptoms due to catecholamine secretion (eg, increased heart rate and blood pressure, excessive sweating, tremor). Paragangliomas may be benign or malignant. Pericardial cystsmay resemble a cardiac tumor or pericardial effusion on chest x-ray. They are usually asymptomatic, although some cause compressive symptoms (eg, chest pain, dyspnea, cough). Malignant primary tumors include sarcomas, pericardial mesothelioma, and primary Overview of Lymphoma . is the most common malignant cardiac tumor. Sarcomas affect mainly middle-aged adults (mean, 44 years). Almost 40% are angiosarcomas, most of which originate in the right atrium and involve the pericardium, causing right ventricular inflow tract obstruction, pericardial tamponade, and lung metastasis. Other types include undifferentiated sarcoma, malignant fibrous histiocytoma, leiomyosarcoma, fibrosarcoma, Rhabdomyosarcoma , liposarcoma, and osteosarcoma; these types are more likely to originate in the left atrium, causing mitral valve obstruction and is rare. It affects all ages, males more than females. It causes Cardiac Tamponade and constriction, and can metastasize to the spine, adjacent soft tissues, and brain. is extremely rare. It usually occurs in patients with HIV/AIDS or other people with Overview of Immunodeficiency Disorders . These tumors grow rapidly and cause Melanoma is a tumor with a high propensity for cardiac involvement. Lung and breast carcinoma, soft-tissue sarcoma, and renal cancer are also common sources of metastases to the heart ( 1.Klatt EC, Heitz DR: Cardiac metastases.Cancer65:1456‒1459, 1990. 