A new treatment option for pulmonary valvar insufficiency: first experiences with implantation of a self-expanding stented valve without use of cardiopulmonary bypass.Eur J Cardiothorac Surg. 2007 Jan; 31(1):26-30.EJ
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.
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.
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%.
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.