Multicenter Pivotal Study of the Alterra Adaptive Prestent for the Treatment of Pulmonary Regurgitation

Abstract

Background: A dilated native right ventricular outflow tract (RVOT) presents unique challenges for transcatheter management using balloon-expandable valves. The Alterra Adaptive Prestent was designed to expand transcatheter therapy to treat patients with dilated RVOTs.

Objectives: The aim of this study was to report 2-year outcomes of the main cohort of the ALTERRA (Multicenter Study of Congenital Pulmonic Valve Dysfunction Studying the SAPIEN 3 THV With the Alterra Adaptive Prestent) pivotal trial using the prestent with transcatheter pulmonary valve replacement.

Methods: The prestent device used with the 29 mm SAPIEN 3 transcatheter heart valve (THV) was evaluated for the management of patients with moderate or greater pulmonary valve regurgitation (PR). The primary endpoint was THV dysfunction at 6 months, defined as a nonhierarchical composite of RVOT/pulmonary valve reintervention, moderate or greater total PR on transthoracic echocardiography, and mean RVOT/pulmonary valve gradient 35 mm Hg or greater on transthoracic echocardiography. The primary endpoint and outcomes through 2 years are presented in this analysis.

Results: Of 97 patients screened, 60 underwent prestent and THV implantation. There was 1 staged procedure. No patients had THV dysfunction at 6 months. At 2 years, the majority of patients (92.5%) had mild or less PR, with no reports of coronary compression, stent fractures warranting reintervention, or endocarditis. Of the 21 patients (34.4%) who experienced early (days 0-1) arrhythmias, 12 had episodes of nonsustained ventricular tachycardia that resolved with medication. One patient underwent reintervention secondary to an iatrogenic RVOT obstruction; there were no deaths or explantations through 2 years.

Conclusions: The Alterra prestent in combination with the SAPIEN 3 THV has excellent outcomes at 2 years, with no significant valve dysfunction in the main pivotal cohort.

Keywords: Alterra Adaptive Prestent; SAPIEN 3 THV; pulmonary regurgitation; right ventricular outflow tract/pulmonary valve dysfunction; transcatheter pulmonary valve replacement.