Cardiac tumors represent a relatively rare, yet challenging diagnosis. Secondary tumors are far more frequent than primary tumors of the heart. The majority of primary cardiac tumors is benign in origin, with primary malignant tumors accounting for 25% of cases. Metastatic tumors usually arise from lung, breast, renal cancer, melanomas, and lymphomas. Clinical manifestations of cardiac tumors depend on the size and location of the mass and the infiltration of adjacent tissues rather than the type of the tumor itself. Echocardiography is the main diagnostic tool for the detection of a cardiac mass. Other imaging modalities (C-MRI, C-CT, 3D Echo) may offer further diagnostic information and the establishment of the diagnosis is made with histological examination. Management depends on the type of the tumor and the symptomatology of the patient.
Cardiac tumors are a challenging and bizarre clinical situation. They are differentiated into primary and secondary (metastatic). The prevalence of primary cardiac tumors is 0.001–0.03% in autopsy series [
Myxoma represents the most frequent benign tumor in adult population [
Lipomas represent the second most frequent primary tumor, and they are usually located in the subepicardium, in the left ventricle, the right atrium, and the interatrial septum. Often they are asymptomatic; however, they may cause arrhythmias, conduction system disturbances, and symptoms of heart failure, especially in cases where they reach a large size [
Papillary fibroelastoma is the most common tumor of the cardiac valves, accounting for 75% of valvular tumors. Papillary fibroelastoma usually affects the elderly (age range
Rhabdomyoma represents the most common cardiac tumor in children. Rhabdomyomas are usually multiple, and they affect the right and the left ventricle likewise. They may cause mechanical complications, such as obstruction of the right ventricular outflow tract. It is also common for rhabdomyomas to regress spontaneously after birth [
Fibroma is the second most common cardiac tumor of childhood, although it may also affect the adult population. Fibromas are intramural tumors, located in the left ventricle, mainly in the intraventricular septum, and they are often mistaken for hypertrophic cardiomyopathy or apical thrombus.
Angiomas, teratomas, and mesotheliomas are rare tumors (accounting for 7% of cardiac tumors), and they affect mainly children. Teratomas are located in the pericardium, and they may lead to constrictive pericarditis.
Primary malignant tumors are relatively rare (accounting for 25% of primary cardiac tumors); they affect ages from 30 to 50 years old, and they are usually sarcomas (angiosarcoma, rhabdomyosarcoma, leiomyosarcoma, liposarcoma, osteosarcoma, fibrosarcoma, and malignant fibrous histiocytoma). Most angiosarcomas are usually located in the right chambers of the heart [
Metastatic cardiac tumours are far more frequent (approximately from 30- to 40-fold) than primary tumors of the heart [
The “carcinoid syndrome” leads to lesions usually in the right heart chambers. It affects mainly the cardiac valves with deposition of fibrous plaques, leading to thickening, shortening, and motion restraint of the tricuspid and/or the pulmonic valve and subsequent regurgitation or stenosis of these valves.
Algorithm for the detection and differential diagnosis of a cardiac tumor. TTE: Transthoracic echocardiography, TEE: Transesophageal echocardiography, 3D Echo: Three dimensional echocardiography, C-MRI: cardiac magnetic resonance, C-CT: Cardiac computed tomography.
Diagnosis and differential diagnosis of cardiac tumors often presents a challenge for the physician. Cardiac tumors, either benign or malignant, are difficult to be diagnosed due to their rarity, variety, and nonspecificity of the symptoms that they may cause. Patient’s history, clinical examination, and blood tests rarely lead to an immediate diagnosis of the tumor; therefore, suspicion of this condition is critical for the correct and timely diagnosis of a cardiac tumor. Furthermore, beyond the performance of imaging techniques (discussed below), histological evaluation via biopsy is essential for the final diagnosis to be established.
Clinical manifestations of cardiac tumors are differentiated in to four categories: systematic manifestations, embolic events, cardiac manifestations, and finally manifestations due to metastases.
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Cardiac tumors may be the cause of
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Regarding cardiac manifestations due to
Finally, primary cardiac tumors can cause symptoms through metastases to other organs. Most frequently, sarcomas metastases affect lungs, brain, and bones.
The imaging techniques that are used when there is a suspicion for the occurrence of a cardiac tumor, as well as for the differential diagnosis of other cardiac masses like vegetations and thrombi, are mainly echocardiography, magnetic resonance imaging (MRI), and computed tomography (CT) of the heart. Chest X-ray can offer indirect findings from the enlargement of cardiac chambers, the occurrence of calcification, or pericardial effusion.
Echocardiography represents a substantial imaging technique for the detection of cardiac tumors with a high sensitivity and specificity (90% and 95%, resp.), and it can be easily performed at the patient’s bedside [
Of interest are newer echocardiographic techniques that may aid in the differential diagnosis of cardiac tumors from other cardiac masses.
The use of cardiac magnetic resonance (C-MRI) with its wide imaging range allows for a better assessment of the tumor relation to adjacent structures, in order for a surgical resection technique to be designed. It also allows the detection of myocardial infiltration by the tumor or expansion of the mass to the pericardium or to adjacent structures [
Cardiac computed tomography (C-CT) can also provide useful information, due to its high resolution and its ability to accurately depict cardiac morphology without limitations because of acoustic windows. Disadvantages of the method include the use of radioactivity and of nephrotoxic contrast mediums. C-CT provides less information regarding characterization of tissues in comparison to C-MRI; however, it can provide some information regarding the nature of the tumor by measuring X-ray attenuation and possible tumor expansion to adjacent tissues. Multidetector computed tomography (MDCT) is useful for the evaluation of calcification and fat content within a mass. Furthermore, the high spatial resolution of MDCT is beneficial to define small lesions, making this technique a useful tool for the staging of malignant tumors [
The diagnosis of cardiac tumors and the estimation of their grade cannot be made with the use of imaging methods only, therefore histological confirmation is necessary. This can be achieved with minimally invasive techniques such as cytological examination of pericardial or pleural fluid or echocardiographically aided percutaneous or transvenous cardiac biopsy. In cases where diagnosis cannot be established, biopsy via thoracoscopy or even thoracotomy may be needed.
Therapy of benign primary cardiac tumors is surgical resection, and the urgency to intervene is determined by the symptoms of the patient and the type of the tumor. Regarding myxomas, immediate surgical resection is indicated, regardless of symptoms, because of the high risk of embolic and cardiac complications. Surgical resection of myxomas confers good results (3% possibility of relapse) and is accompanied with small rates of periprocedural mortality (<5%). Papillary fibroelastomas are surgically removed in cases of large (>1 cm) and/or mobile tumors. In cases of small, immobile tumors in the left ventricles, conservative management and close follow-up may be advocated. However, because of their fragile nature, papillary fibroelastomas carry a high risk of embolic complications; therefore, most authors propose surgical management even in asymptomatic patients [
Regarding malignant primary cardiac tumors, their prognosis is dismal, since they tend to infiltrate the myocardium rapidly, cause obstruction of the cardiac chambers and produce metastases. Management of choice in sarcomas is surgical resection, with poor results and high rates of relapse [
Finally, regarding cardiac manifestations due to metastatic extracardiac cancer, priority is given to the management of the primary focus of the disease and the cardiovascular complications that are manifested (i.e., percutaneous balloon pericardiotomy in cases of cardiac tamponade, radiotherapy and chemotherapy in cases of tumors that obstruct flow in the venae cavae, etc.).