Echocardiography in malignant cardiac tumors (diagnosis, approach, and follow-up)





Key points




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    Most malignant cardiac tumors are metastatic, most commonly from lung and breast carcinomas, melanomas, soft tissue sarcomas, and renal carcinomas.


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    Malignant primary cardiac tumors are rare and mostly consist of various sarcomas and lymphomas.


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    Twenty-five percent of primary cardiac tumors are malignant.


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    Echocardiography is a readily available, portable, low-cost imaging modality that gives the first clue as to the etiology of a cardiac mass. The characteristics of a mass such as location, mobility, attachment, and appearance can help determine whether a mass is benign or malignant.


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    Magnetic resonance imaging offers incremental value owing to its larger field of view, superior tissue contrast, versatility in image planes, and unique ability to enable the discrimination of different tissue characteristics such as water and fat content, causing particular signal patterns with T1- and T2-weighted techniques ( Table 9.1 ; Chart 9.2 ; Figs. 9.3 and 9.4 ).



    Table 9.1

    Imaging features suggesting benign and malignant cardiac tumors .






























































    Imaging features suggesting benign and malignant cardiac tumors
    Features Benign Malignant
    Site/number Small (< 5 cm), single lesion Large (≥ 5 cm), multiple lesions
    Location Left ≫ Right Right ≫ Left
    Morphology Intracameral Intramural
    Attachment Narrow stalk, pedunculated Broad base
    Borders Smooth/well defined Irregular
    Invasion None Free wall and adjacent structures
    Pericardial effusion None May be present
    Calcification Rare Large foci in osteosarcomas
    CT enhancement Absent/minimal Modest/intense
    CMR T1W-TSE Predominantly isointense Predominantly isointense
    CMR T2W-TSE Predominantly hyperintense Predominantly hyperintense or isointense
    First-pass perfusion May be present Very frequent (70%)
    Delayed enhancement Usually present Very frequent (80%)

    CMR , cardiac magnetic resonance; CT , computed tomography; T1W-TSE , T1-weighted sequences turbo-spin-echo; T2W-TSE , T2-weighted sequences turbo-spin-echo.



    Chart 9.2


    (Left) World Health Organization classification of malignant cardiac tumors. (Right) The image depicts the frequency distribution of cardiac sarcomas.



    Fig. 9.3


    The images illustrate the mechanisms of cardiac involvement in neoplasms .



    Fig. 9.4


    The images demonstrate a lymphoma visualized by transthoracic echocardiography in a 24-year-old man with a history of a mediastinal lymphoma 2 years previously subjected to chemotherapy and radiotherapy. The patient presented with fatigue and exertional dyspnea (functional class II). The echocardiographic findings reveal a large, mural, echogenic mass in the right ventricular outflow tract (white arrows) , measuring about 3.5 cm × 4.7 cm in size. The mass results in a moderate obstruction (peak gradient = 52 mmHg) and extends into the pulmonary artery branches. Additionally, a large heterogeneous pericardial effusion can be observed with the tumoral involvement of the pericardial cavity (yellow arrows) .



Primary cardiac lymphomas are extremely rare in that they account for fewer than 2% of heart tumors. The most common pathological type is diffuse large B-cell lymphomas, followed by Burkitt lymphomas, T-cell lymphomas, small lymphocyte lymphomas, and plasmablastic lymphomas. The most frequent pathological types of secondary cardiac lymphoma are diffuse large B-cell lymphomas, T-lymphoblastic lymphomas, and Hodgkin lymphomas. Because most cardiac lymphomas are secondary, tumors outside the heart appear before cardiac tumors. Through the invasion of the mediastinum or the surrounding mass, the lymphatic circulation, or blood dissemination, the heart is involved and heart-related symptoms appear. Therefore most of the relevant cardiac symptoms are late or mild, indicating that they can be easily ignored .


Cardiac lymphomas are easily missed or misdiagnosed, and medical personnel must increase their awareness of this malignancy. Echocardiography cannot be excluded from diagnostic examinations. In addition, the extensive application of positron emission tomography, which combines imaging and functional metabolism, effectively reveals the proliferation and metabolism of tumors throughout the body. It represents a more accurate method for the diagnosis and treatment of lymphomas with cardiac involvement ( Fig. 9.5 ).




Fig. 9.5


The images illustrate cardiac metastases of an osteosarcoma. The transthoracic echocardiographic examination of a 61-year-old woman with a history of an osteosarcoma with lung metastases shows a large homogeneous left atrial mass (4.6 cm × 4 cm), which almost fills the atrium and originates from the left pulmonary veins and extends into the left atrium (black arrows) . The mass is the extension of the lung tumor from the pulmonary veins into the heart.


Although osteosarcomas are known to spread hematogenously, few imaging findings of cardiovascular involvement by osteosarcomas have been reported. Imaging findings of cardiovascular involvement by osteosarcomas can be subtle and are, thus, likely to be missed or misinterpreted, with potentially undesirable consequences. The incidence of cardiovascular metastases and the impact of its early recognition are not clear. Cardiovascular involvement usually happens early in the course of the disease within the systemic vein draining the primary tumor and in small pulmonary arterial branches, and in advanced cases within the veins draining the lung and extrapulmonary metastases. Extension into the left atrium is generally considered a feature of advanced osteosarcomas ( Figs. 9.6–9.8 ).




Fig. 9.6


The images show mediastinal germ cell tumors. The parasternal short-axis view shows that the right atrium is filled with a large heterogeneous mass (A, white arrow ). The pulmonary trunk is infiltrated with a huge, heterogeneous mass that compresses the branches (A, black arrows ), resulting in right ventricular dilatation and dysfunction. The chest X-ray shows the right-heart border silhouette (B, white arrows ), suggestive of right-side enlargement with a mediastinal origin. Mediastinal germ cell neoplasms are rare and account for between 10% and 15% of all the mediastinal tumors. These tumors are usually asymptomatic and discovered incidentally during routine chest X-rays. Considering the close relationship between mediastinal germ cell tumors and the heart, echocardiography by an experienced cardiologist may be necessary for early detection .



Fig. 9.7


The images depict metastatic melanomas involving the heart visualized by transthoracic echocardiography in 2 patients. A huge, semimobile, heterogeneous mass (A, white arrows ) is seen attached to the mitral-annular intervalvular fibrosa, causing a life-threatening left ventricular outflow obstruction ( Supplementary Video 9.S1 ). Multiple heterogeneous lesions can be seen with myocardial and pericardial invasions (B, C, and D, black arrows ), suggestive of metastatic lesions. Malignant melanomas involve the heart frequently. However, they are diagnosed late in the course of the disease due to the absence of specific clinical signs and the low sensitivity of routine examinations. Complementary imaging modalities, including transesophageal echocardiography, cardiac magnetic resonance, and fluorodeoxyglucose-positron emission tomography, represent major advances in the assessment of metastatic melanomas .

The images depict metastatic melanomas involving the heart visualized by transthoracic echocardiography in 2 patients. A huge, semimobile, heterogeneous mass (A, white arrows ) is seen attached to the mitral-annular intervalvular fibrosa, causing a life-threatening left ventricular outflow obstruction (Supplementary Video 9.S1 in the online version at https://doi.org/10.1016/B978-0-323-84906-7.00001-7 ). Multiple heterogeneous lesions can be seen with myocardial and pericardial invasions (B, C, and D, black arrows ), suggestive of metastatic lesions. Malignant melanomas involve the heart frequently. However, they are diagnosed late in the course of the disease due to the absence of specific clinical signs and the low sensitivity of routine examinations. Complementary imaging modalities, including transesophageal echocardiography, cardiac magnetic resonance, and fluorodeoxyglucose-positron emission tomography, represent major advances in the assessment of metastatic melanomas .



Fig. 9.8


The images illustrate 2 cases of cardiac metastases of hepatocellular carcinomas. (A and B) A large, multilobulated, semimobile, heterogeneous mass is seen in the right atrium (A, white arrows ). The axial image in the computed tomography scan shows a large mass in the liver and its invasion to the right atrium (B, white arrows ). The parasternal long-axis (C), parasternal short-axis (B), and apical 4-chamber (E) views of the transthoracic echocardiographic examination of a patient with a history of a hepatocellular carcinoma with metastases to the lung show a mobile mass with infiltration to the left atrium through a pulmonary vein.


Advanced hepatocellular carcinomas represent a disease with a poor prognosis and a median survival time of 4 to 7 months. Hepatocellular carcinoma metastases tend to spread through the intrahepatic blood vessels and the lymphatic system or direct infiltration. They frequently invade the vascular system at points such as the portal and hepatic veins. The extrahepatic metastases of hepatocellular carcinomas may reach around 18%, with the most common sites of involvement being the lungs, lymph nodes, adrenal glands, and bones. The intracardiac involvement of hepatocellular carcinomas rarely develops (2%), and the main mechanism of metastases into the cardiac cavity is the direct extension of the tumor to the heart via the hepatic vein and the inferior vena cava. The prognosis of hepatocellular carcinomas with intracardiac metastases is poor, with a median survival range of 1 to 4 months. The most common causes of death in patients with hepatocellular carcinomas with intracardiac involvement are heart failure and sudden death, which account for 25% of the patients. Most patients with right-sided metastases will have signs and symptoms of right-sided heart failure, or they could be totally asymptomatic. Irrespective of the symptoms, the presence of right-sided metastases renders the prognosis extremely poor. Other cardiac symptoms or findings such as dyspnea, lower extremity edema, dilatation of the jugular veins, and sudden death are generally seen in hepatocellular carcinomas with intracardiac involvement. Echocardiography is widely available, and it provides a simple, noninvasive technique for the initial evaluation of the cardiac involvement of any tumor. Echocardiography images both the myocardium and the cardiac chambers and can usually identify the presence of a mass in conjunction with its mobility and functional effects. Both computed tomography (CT) and magnetic resonance imaging (MRI) provide noninvasive, high-resolution images of the heart and the liver. MRI is generally preferred since, in addition to furnishing detailed anatomic images, it offers clues as to the type of tumor ( Fig. 9.9 ).


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Nov 10, 2024 | Posted by in CARDIOLOGY | Comments Off on Echocardiography in malignant cardiac tumors (diagnosis, approach, and follow-up)

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