Alterra Adaptive Prestent and SAPIEN 3 THV for Congenital Pulmonic Valve Dysfunction: An Early Feasibility Study

The aim of this study was to demonstrate the safety and functionality of the Alterra Adaptive Prestent and SAPIEN 3 transcatheter heart valve (THV) in patients with dysfunctional, dilated right ventricular outflow tract (RVOT) greater or equal to moderate pulmonary regurgitation (PR).

Significant variations in the size and morphology of the RVOT affect the placement of transcatheter pulmonary valves. The Alterra Prestent internally reduces and reconfigures the RVOT, providing a stable landing zone for the 29-mm SAPIEN 3 THV.

Eligible patients had moderate or greater PR, weighed >20 kg, and had RVOT diameter 27 to 38 mm and length >35 mm. The primary endpoint was device success, a 5-item composite: 1 Alterra Prestent deployed in the desired location, 1 SAPIEN 3 THV implanted in the desired location within the Prestent, right ventricular-to-pulmonary artery peak-to-peak gradient <35 mm Hg after THV implantation, less than moderate PR at discharge, and no explantation 24 h post-implantation. The secondary composite endpoint was freedom from THV dysfunction (RVOT/pulmonary valve (PV) reintervention, greater or equal to moderate total PR, mean RVOT/PV gradient ≥ 35 mm Hg at 30 days and 6 months. Descriptive statistics are reported.

Enrolled patients (N = 15) had a median age and weight of 20 years and 61.7 kg, respectively; 93.3% were in New York Heart Association functional class I or II. Device success was 100%. No staged procedures were necessary. No THV dysfunction was reported to 6 months. No serious safety signals were reported.

This early feasibility study demonstrated the safety and functionality of the Alterra Adaptive Prestent in patients with congenital RVOT dysfunction and moderate or greater PR. Durability and long-term outcome data are needed.