Benign Primary Cardiac Tumors
Myxoma is the most frequent of the benign cardiac tumors (Fig. 20-1, Video 20-01), accounting for 30% to 50% and affecting mostly women1 in the third through sixth decades; more than 90% are sporadic. They are located mostly in the left atrium (75%),2–4 and rarely elsewhere (right atrium 18%, right ventricle 4%, and left ventricle 4%). Myxomas can present as multiple lesions, are pedunculated (typically attached by a narrow stalk to the endocardial surface of the left atrial side of the fossa ovalis), and are rarely sessile, polypoid, or multilobar, sometimes with a smooth and rounded surface. Myxomas are friable tumors, contain a mucopolysaccharide myxoid matrix, and have a nonhomogeneous appearance on transesophageal echocardiography (TEE) because of the presence of channels, cystic areas, hemorrhage, or calcifications (Fig. 20-2, Video 20-02). Their morphology can be analyzed with real-time 3D echocardiography5 to enable differentiation from thrombus (less frequently located in the interatrial septum and with a small, less organized stalk) and diagnose underlying mitral valve disease (Fig. 20-1B).
Left atrial myxoma in midesophageal two-chamber (A) and 3D five-chamber views (B) seen partially occluding the left atrial appendage (asterisk). LA, left atrium; LV, left ventricle.
Video 20-01: Left atrial myxoma in midesophageal long-axis view.
Right atrial myxoma attached to the interatrial septum. Midesophageal four-chamber view rotated toward the right demonstrating a heterogeneous appearance with calcification and translucent zones. LA, left atrium; RA, right atrium.
Video 20-02: Right atrial myxoma attached to the interatrial septum.
A typical triad of symptoms includes embolization (brain, coronary, or any systemic vessel), obstruction, and constitutional symptoms such as dyspnea, position-related palpitations, syncope, congestive heart failure, and even sudden death. Obstructive symptoms vary from turbulence on color flow Doppler due to ventricular inflow obstruction (atrial myxoma)6 (Fig. 20-3), or ventricular outflow obstruction (subaortic or right ventricular myxoma).7 Right atrial myxomas tend to be more solid, have wider attachments, and may be fixed to the inferior rim of the fossa ovalis, the tricuspid valve, or the Eustachian valve (Fig. 20-2).
Left atrial myxoma seen in the midesophageal four-chamber view with color flow Doppler demonstrating obstruction of blood flow through the mitral valve. LA, left atrium; LV, left ventricle; RV, right ventricle.
Rhabdomyoma is the most frequent cardiac tumor in infants and children and is associated with tuberous sclerosis.8,...