Percutaneous pulmonary valve implantation in patients with dysfunction of a "native" right ventricular outflow tract - Mid-term results.

BACKGROUND: To investigate the feasibility and mid-term results of percutaneous pulmonary valve implantation (PPVI) in patients with conduit free or "native" right ventricular outflow tracts (RVOT). METHODS AND RESULTS: We identified all 18 patients with conduit free or "native" right ventricular outflow tract, who were treated with percutaneous pulmonary valve implantation (PPVI) in our institution. They were divided into two groups - these in whom the central pulmonary artery was used as an anchoring point for the preparation of the landing zone (n=10) for PPVI and these, in whom a pulmonary artery branch was used for this purpose (n=8). PPVI was performed successfully in all patients with significant immediate RVOT gradient and pulmonary regurgitation grade reduction. Four patients had insignificant paravalvular regurgitation. In one patient the valve was explanted after 4months because of bacterial endocarditis. A follow-up of 19 (4-60) months showed sustained good function of the other implanted valves. The MRI indexed right ventricular end diastolic volume significantly decreased from 108(54-174) ml/m2 before the procedure to 76(60-126) ml/m2 six months after PPVI, p=0.01. CONCLUSIONS: PPVI is feasible with good mid-term results in selected patients with a "native" RVOT without a previously implanted conduit. Creating a stable landing zone with a diameter less than the largest available valve (currently 29mm) is crucial for the technical success of the procedure. Further studies and the development of new devices could widen the indications for this novel treatment.