Contrast-Enhanced Echocardiography in Spindle Cell Sarcoma of the Pericardium
A 37-year-old male was admitted from the emergency department for evaluation of symptoms of congestive heart failure. He presented having experienced atypical chest pain, progressive dyspnea, and swelling of the legs for 2 weeks. Physical examination was notable for tachycardia, elevated jugular venous pressure, muffled heart sounds, and bilateral pitting pedal edema. An ECG showed sinus tachycardia and low-voltage complexes, and chest x-ray revealed cardiomegaly. A 2-dimensional echocardiogram was done to evaluate cardiac chambers and left ventricular function. Surprisingly, it showed compression of the right atrium and right ventricle by a large mass possibly originating from the pericardium, dilated inferior vena cava, no significant respiratory variation in transmitral and tricuspid Doppler velocities, and expiratory reversal of flow in the hepatic veins. A contrast echocardiogram was performed to further assess the cardiac chambers and their relationship to the mass. One milliliter of optison (Amersham Health, Princeton, NJ) was injected, and the mass was imaged in real time (SONOS 7500, Philips Medical systems, Andover, Mass). The gain and compression settings were optimized for visualization of perfusion. The contrast injection confirmed the compression of right-sided chambers and exquisitely demonstrated distribution of contrast in the mass, suggesting it to be highly vascular (Figure 1 and Movie I). The echocardiograph findings were confirmed by cardiac magnetic resonance imaging (Figure 2). The patient underwent ultrasound-guided core biopsy of the mass, which showed the tumor to be pericardial spindle cell sarcoma (Figure 3). Immunostaining was negative for thymoma and lymphoma.
Radiologic imaging suggested the tumor to be large, with the possibility of local invasion. The patient received neoadjuvant chemotherapy with 5 cycles of mesran, adriamycin, and ifosfamide in addition to radiotherapy. This resulted in significant reduction in tumor size. The patient subsequently underwent surgery, and the tumor (Figure 4), measuring about 21 cm in size, was removed through a median sternotomy. During surgery, the mass was found to originate from the pericardium, encasing the whole anterior aspect of the heart except at the base, and invading the right ventricular apex. Histopathological examination of the surgical specimen confirmed the predominant involvement of the pericardium and invasion of the myocardium by the tumor. A postoperative contrast echocardiogram revealed complete decompression of the right atrium and right ventricle. Minimal contrast enhancement and a vascular pedicle were visualized in the residual tumor close to the right ventricle (Figure 5 and Movie II).
Transthoracic echocardiography is the primary diagnostic modality used for the evaluation of cardiac masses.1,2 Recently, microbubble agents have been used to enhance image acquisition; they also have been found useful for differentiating malignant tumors from benign or avascular thrombus.3–5 Malignant tumor is characterized by increased vascularity and is identified by greater pixel intensity in the mass than in the adjacent myocardium during perfusion imaging. This differentiation has major therapeutic implications.
Increased vascularity is illustrated by the tumor blush and its origination from the myocardium. Contrast echocardiography indicated that the tumor was likely malignant and possibly invaded the right ventricular myocardium. These findings significantly correlated with surgical and histopathological results.
The online-only Data Supplement, consisting of movies I and II, is available with this article at http://circ.ahajournals.org/cgi/content/full/115/11/e329/DC1.