Anastomotic pseudoaneurysm of the ventricle after homograft placement in children

A pseudoaneurysm of the right ventricle was diagnosed postoperatively in 8 patients between 1986 and 1992. One pseudoaneurysm formed after placement of a CarpentierEdwards conduit and the other seven arose after placement of a homograft between the right ventricle and the pulmonary artery. Both aortic (n = 3) and pulmonary (n = 4) homografts had been used. In 6 patients, the homografts had been augmented proximally with Dacron, Gore-Tex, or pericardium. Pseudoaneurysms originated between the augmentation patch and the homograft in 4 patients, between the homograft or conduit and the myocardium in 3 patients (1 patient with and 2 without an augmentation patch), and between the patch and the myocardium in 1 patient. The prior operations performed were placement of a palliative conduit for tetralogy of Fallot with pulmonary atresia (n = 5), repair of truncus arteriosus (n = 2), and repair of absent pulmonary valve syndrome (n = 1). Pseudoaneurysms were discovered from 5 weeks to 4 years after the operation. Symptoms were present in 3 patients; in the others, diagnosis was made during follow-up on the basis of routine imaging studies. Symptoms, when present, were due to compression of surrounding mediastinal structures. Pseudoaneurysms ranged in diameter from 1.0 to 5.0 cm. Echocardiography and color-flow mapping reliably identified the pseudoaneurysm in the 6 patients in whom it was performed. Characteristic features included a well-defined, narrow aneurysm neck leading to an extracardiac echo-free space. Color-flow mapping demonstrated to-and-fro flow through the neck of the aneurysm. Right ventricular pressure was half the systemic pressure or less in 2 patients and was the same as or exceeded the systemic pressure in 6 patients. The pseudoaneurysm was surgically repaired in 7 patients; in the eighth patient, the neck of the pseudoaneurysm was closed with a double-umbrella, clamshell device in the catheterization laboratory. A pseudoaneurysm of the right ventricle forms infrequently after the placement of a homograft or conduit between the right ventricle and the pulmonary artery and is probably multifactorial in origin, though it is frequently associated with systemic right ventricular pressure. This defect can be diagnosed easily by echocardiography and successfully treated.