Failure of mechanical valves in Ebstein's malformation.

Five patients with Ebstein's malformation were operated on with closure of the atrial septal defect and implantation of a mechanical prosthesis at the right atrioventricular junction. The 4 patients who survived showed an excellent early recovery. Three of the patients noticed the disappearance of the valve clicks 6 months after the operation. At re-examination using echophonocardiography, peripheral dye dilution curves and catheterization, these valves were found to be stuck in the open position in 2 patients and in the closed position in 1 patient. The last patient had a paravalvar channel supplying blood into the right ventricle. One patient who had a St. Jude prosthesis was doing excellently 4 years postoperatively and the valve was functioning well. Two years after the operation, the other patient with a St. Jude valve again noticed valve clicks after over 1 year of silence. Examination revealed the prosthesis to be functioning normally. The totally occluded Björk-Shiley prosthesis (10 years postoperatively) was excised at re-operation and replaced by an Ionescu-Shiley bioprosthesis. The patient with a jammed Björk-Shiley prosthesis (10 years postoperatively) declined a re-operation and is doing well, albeit under close observation.