Harmony Feasibility Trial: Acute and Short-Term Outcomes With a Self-Expanding Transcatheter Pulmonary Valve

Objectives: This study sought to obtain in vivo data to confirm assumptions on device loading conditions and assess procedural feasibility, safety, and valve performance.

Background: The Harmony transcatheter pulmonary valve (Medtronic, Minneapolis, Minnesota) was designed for patients with severe pulmonary regurgitation who require pulmonary valve replacement.

Methods: Three sites participated in this first Food and Drug Administration-approved early feasibility study using an innovative device design to accommodate the complex anatomy of the right ventricular outflow tract. Potentially eligible patients underwent review by a screening committee to determine implant eligibility. Six-month outcomes are reported.

Results: Between May 2013 and May 2015, 66 subjects were enrolled, and 21 were approved for implant and underwent catheterization; 20 were implanted. Catheterized patients had a median age of 25 years, were predominantly diagnosed with tetralogy of Fallot (95%), had severe pulmonary regurgitation (95%), and had trivial or mild stenosis. The device was delivered in the desired location in 19 of 20 (95%) patients. Proximal migration occurred in 1 patient during delivery system removal. Two devices were surgically explanted. Premature ventricular contractions related to the procedure were reported in 3 patients; 2 were resolved without treatment. One patient had ventricular arrhythmias that required treatment and later were resolved. At 1 month, echocardiography revealed none or trivial pulmonary regurgitation in all and a mean right ventricular outflow tract gradient of 16 ± 8 mm Hg (range 6 to 31 mm Hg).

Conclusions: In this feasibility study of the Harmony transcatheter pulmonary valve device, there was high procedural success and safety, and favorable acute device performance.