A 12-year-old previously healthy boy presented with a heart murmur and was found by transthoracic echocardiography to have a single mobile tumor in the right ventricular outflow tract with mild obstruction (Movies I and II). A cardiac MRI was performed to determine the tumor’s tissue type and further depict its relationship to other cardiac structures. A diagnosis of probable cardiac hemangioma was made on the basis of its MRI signal intensity characteristics, including rapid enhancement during first-pass gadolinium contrast infusion, indicating high vascularity (Figure 1 and Movies III and IV). Other cardiac tumors that may have strong gadolinium enhancement include pheochomocytoma, angiosarcoma, myxoma, and rhabdomyosarcoma; however, these all were considered unlikely on the basis of the patient’s age, tumor location, and clinical presentation. The tumor was surgically excised through a small infundibulotomy, and the patient had an uneventful recovery, except for a single episode of unsustained ventricular tachycardia on the first postoperative night. Pathology examination showed an endocardial pedunculated lesion composed of thin-walled dilated channels with intervening diffuse capillary proliferation, an immunohistochemical profile consistent with hemangioma, and a normal karyotype (Figure 2). Vascular primary cardiac tumors such as hemangioma account for <10% of all primary cardiac tumors in children and are usually asymptomatic when diagnosed after infancy.1 This case illustrates how vascular cardiac tumors can be diagnosed noninvasively by MRI via a combination of imaging sequences for tissue characterization.
The Data Supplement, which contains 4 movies, is available at http://circ.ahajournals.org/cgi/content/full/112/8/e103/DC1.
Mackie AS, Kozakewich HP, Geva T, Perez-Atayde AR, Mulliken JB. Vascular tumors of the heart in infants and children: case series and review of the literature. Pediatr Cardiol. Published ahead of print November 18, 2004. DOI: 10.1007/s00246-004-0717-2. Available at: http://www.springerlink.com/link.asp?id=jhcwjp3anfb47deg. Accessed July 27, 2005.