(CCSP031) TWO-YEAR OUTCOMES IN AN EXPANDED COHORT OF HARMONY TRANSCATHETER PULMONARY VALVE RECIPIENTS

Background: The Harmony transcatheter pulmonary valve (TPV), the first United States FDA-approved device for severe pulmonary regurgitation (PR) in the native or surgically repaired right ventricular outflow tract (RVOT), is now approved in Canada. The purpose of this study is to report 2-year safety and effectiveness in patients from an expanded cohort of Harmony clinical trial participants. Due to data availability at the time of submission, the 1-year outcomes are reported here, and the 2-year outcomes by valve type will be presented. This is an encore submission of data that will be presented at SCAI on 20 May 2023 and will be submitted for consideration as an encore presentation at PICS 2023.

METHODS AND RESULTS: The analysis included patients who received a commercially available TPV22 or TPV25 device (Medtronic, Minneapolis, MN) as part of the Harmony Native Outflow Tract Early Feasibility Study (EFS), Harmony TPV Pivotal Trial, and Continued Access Study. Eligible patients had severe PR by echocardiography or PR fraction ≥30% by cardiac magnetic resonance imaging and a clinical indication for pulmonary valve replacement. There were 86 patients in the implanted cohort (42 TPV22; 44 TPV25); an additional patient had a valve-in-valve procedure on Day 0 and was not included in the implanted cohort. Median (Q1, Q3) patient age at treatment was 29 (18, 39) years and 87% had an original diagnosis of tetralogy of Fallot. At 1 year, all patients were alive, and freedom from the composite of PR, stenosis, and reintervention (defined as ≥moderate PR, mean RVOT gradient >40 mmHg, device-related RVOT reoperation, and catheter reintervention) was 95% in TPV22 and 91% in TPV25 patients. One-year freedom from major stent fracture was 98% in TPV22 and 100% in TPV25 patients. None/trace or mild PR was present in 98% of TPV22 and 100% of TPV25 patients at 1 year. Two TPV22 patients from the EFS were explanted on Day 2 and Day 39, respectively. One TPV25 patient in the implanted cohort underwent a valve-in-valve procedure on Day 303. Fourteen (3 TPV22, 11 TPV25) patients had nonsustained ventricular tachycardia (NSVT), which initiated during the implant procedure in 13 patients and at 1-day postimplant in 1 patient. There were no serious adverse events related to the NSVT.

Conclusion: Harmony TPV patients in this expanded analysis cohort had favorable clinical and hemodynamic outcomes across studies and valve types through 1 year, and the upcoming 2-year analysis will expand our understanding of this patient population.