The largest cohort to date of patients with congenital heart disease and severe pulmonary regurgitation (PR) who received the Harmony transcatheter pulmonary valve demonstrated favorable clinical and hemodynamic outcomes at 1 year. Daniel S. Levi, MD, of Mattel Children’s Hospital at UCLA presented these results Thursday as late-breaking science at the Society for Cardiovascular Angiography & Interventions (SCAI) 2022 Scientific Sessions. The Harmony transcatheter pulmonary valve (TPV) is the first approved device to treat severe PR in the native or surgically repaired right ventricular outflow tract (RVOT). The pooled analysis evaluated the 1-year safety and effectiveness in patients from the Harmony Native Outflow Tract Early Feasibility Study (EFS), Harmony transcatheter pulmonary valve (TPV) pivotal trial, and the continued access study (CAS). Three iterations of the Harmony valve (Medtronic) were included in the analysis. The TPV22 is an amino-oleic acid (AOA) treated porcine pericardial tissue valve, designed with a knitted polyester cloth covering and self-expanding nitinol frame. The valve comes in 22 mm and 25 mm diameters with a single 25-French delivery system. An early iteration of the 25-mm valve, called the clinical TPV25 (cTPV25), was designed to treat a wider range of patients, but it was discontinued after it was found to have less predictable deployment The modified TPV25 (mTPV25), which along with the TPV22 is still in use, was modified to improve the predictability of valve deployment. Previous studies have demonstrated stable position and sustained valve function of the TPV22 through 5 years in the EFS, and favorable clinical and hemodynamic outcomes of the TPV22 and mTPV25 through 1 year in the pivotal trial and 6 months in the CAS. Patients with severe PR on echocardiography or PR fraction ≥30% by cardiac magnetic resonance imaging with a clinical indication for pulmonary valve replacement were included in the pooled analysis. A total of 108 patients who had completed 1-year follow-up were catheterized (21 EFS, 50 pivotal trial and 37 CAS) and 106 had valves implanted. Of these, 67 pivotal and CAS patients were implanted with TPV22 or mTPV25 valves, 20 EFS patients received the TPV22 valve, and remaining 19 pivotal-trial patients received the cTPV25. At baseline, the patients’ mean age was 29.0 ± 12.7 years, 38% were female, and 86.1% had a diagnosis of Tetralogy of Fallot. Nearly all patients, 96.3%, had severe PR by echocardiography. The primary safety endpoint was freedom from procedure- or device-related mortality at 30 days. The primary efficacy endpoint was the proportion of patients with favorable hemodynamics at 6 months’ follow-up such as mean RVOT gradient ≤40 mmHg, and PR fraction <20%. A clinical events committee adjudicated adverse events. Of 106 patients with TPV implant, and 104 remained implanted for >24 hours, and two patients with the cTPV25 valve required surgery. The primary safety endpoint of freedom from all-cause mortality was 100% at 1 year, and there was no endocarditis in any of the patients. Levi added that ventricular tachycardia occurred in 17.6% of patients, but none of it was sustained tachycardia. At 1 year, 92% of patients had none or trace PR, 3% had mild PR, and 4% had moderate PR.. The majority of patients, with TPV22 (95.1%) and mTPV25 (89.7%) were free from PR, pulmonary stenosis and interventions at 1 year. Major stent fracture was noted in one EFS patient at 1-month follow-up. There were four explants, two with the TPV22 in the EFS cohort and two with the discontinued cTPV25. Four patients needed reinterventions, two with the discontinued cTPV25 and two with the mTPV25. When asked during a press conference about the lower freedom from PR, stenosis and interventions of the newer mTPV25 compared with the older TPV22, Levi explained that one mTPV25 patient had neointimal growth on the valve and another patient’s valve was mis-sized, meaning both of those patients had to be reimplanted with new valves. With the study’s relatively small sample size, Levi said, those two patients “probably skewed the results.” “It is a good pickup,” Levi acknowledged, “because we would probably like that number to be bigger than 90%.” Levi concluded that the favorable clinical and hemodynamic outcomes at 1 year confirm the earlier short-term results and demonstrate continued device safety and effectiveness of valve types at 1-year. “Even a year after implant, the valve is continuing to function well without significant interventions, obstruction or regurgitation,” he said in a news release announcing the results. “This gives us confidence that we are going down the right treatment path with this pulmonary valve.” The study, which was sponsored by Medtronic, will continue follow up through 10 years. Jason Wermers contributed to this report. Image Credit: U.S. Food and Drug Administration