Objective: Pulmonary regurgitation is the predominant problem in the long-term follow-up of tetralogy of Fallot (TOF) patients after primary repair. Apart from standard homograft implantation, a percutaneous valve delivery approach has been described recently. A right ventricular outflow tract (RVOT) diameter of greater than 22mm, however, precludes percutaneous valve delivery. We describe a novel technique with a transventricular implantation of a stented bio-prosthesis without cardiopulmonary bypass that allows for implantation of prosthesis with diameters greater than 22mm.
Methods: All patients (9-27 years of age) had undergone total correction of TOF at a mean age of 4.2+/-4.0 years. The RVOT was enlarged at that time with a transannular patch in all but one patient. All patients presented with severe pulmonary regurgitation without any significant RVOT obstruction. Mean MRI pulmonary regurgitation was 53+/-8%. The mean magnetic resonance imaging (MRI) right ventricular end diastolic volume index (RVEDVI) was 143+/-23ml/m(2), with a mean MRI right ventricular ejection fraction (RVEF) of 46+/-9%. In another two patients indication for treatment was based on reduced exercise capacity with patients being in NYHA Class III. After repeat sternotomy, a porcine valve mounted inside a self-expandable stent, covered with No-React treated porcine pericardium (Shelhigh, Model NR-4000MIS), was introduced just beneath the RVOT without use of cardiopulmonary bypass. External sutures were placed at the proximal and distal site of the valve to ensure fixation.
Results: The implantations were uneventful, with the patients hemodynamically stable throughout the procedure. One patient with severely dilated RVOT (up to 31mm) exhibited paravalvular leakage and the valve was replaced by a homograft after 2 days. At 6-12 month follow-up the remaining five patients exhibited no more than mild pulmonary regurgitation. The mean MRI RVEDVI was 94+/-18ml/m(2), with a mean MRI RVEF of 58+/-27%.
Conclusions: Cardiopulmonary bypass for repeat RVOT interventions can be avoided in selected patients with this newly available device. In combination with a wide range of prosthesis sizes it offers yet another important treatment option.