Among 1022 patients who underwent total repair of tetralogy of Fallot, 252 patients received a pericardial patch of the right ventricular outflow tract (RVOT); and of these 10 subsequently developed an aneurysm of the RVOT. Cardiac catheterization and angiography revealed moderate pulmonary unsufficiency in all patients, a residual pressure gradient in the RVOT in seven and a residual ventricular septal defect in two patients. Surgery was indicated in eight patients because of progressive distension of the aneurysm. Reconstruction of the RVOT was accomplished by resection of the aneurysm and insertion of a woven Dacron patch in five patients, primary suture of the pulmonary artery in two and implantation of a woven Dacron conduit containing a Björk-Shiley valve in one patient. No early or late death occured. Although aneurysms of the RVOT with pericardial patches represent a rare complication after total correction of tetralogy of Fallot, we recommend primary reconstruction of the RVOT with a woven Dacron patch.