Jones TK, McElhinney DB, Vincent JA, Hellenbrand WE, Cheatham JP, Berman DP, Zahn EM, Khan DM, Rhodes JF Jr, Weng S, Bergersen LJ.
Circ Cardiovasc Interv. 2022 Jan;15(1):e010852. doi: 10.1161/CIRCINTERVENTIONS.121.010852. Epub 2021 Dec 21.PMID: 34930015
Commentary from Dr. Milan Prsa (Switzerland, Europe), section editor of Congenital Heart Disease Interventions Journal Watch
Take Home Points:
- In patients with dysfunctional right ventricular outflow tract conduits and bioprosthetic pulmonary valves, transcatheter pulmonary valve replacement with the Melody valve showed an estimated 10-year survival of 90% and an estimated 10-year freedom from reintervention of 60%, which is not inferior to surgical management.
- Implantation at a younger age in a smaller right ventricular outflow tract conduit or bioprosthetic pulmonary valve was a risk factor for reintervention.
- Endocarditis was the leading cause of death with the annualized rate of Melody valve-related endocarditis of 2.0% per patient-year.
The Melody transcatheter pulmonary valve (TPV) has revolutionized the care of patients with dysfunctional right ventricular outflow tract (RVOT) conduits and bioprosthetic pulmonary valves (BPV), decreasing their lifetime burden of repeat surgery. However, data on long-term outcomes beyond 5 years after implant has been seriously lacking. The results of this 10-year follow-up in the US Investigational Device Exemption (IDE) study of the Melody valve are therefore a much-needed addition to the literature.
The trial included patients ≥5 years of age and ≥30 kg who had a dysfunctional RVOT conduit ≥16 mm in diameter or a stented BPV with internal diameter 18-22 mm at time of implant. Conduit or valve dysfunction was defined as moderate (3+) or severe (4+) pulmonary regurgitation (PR), or mean RVOT gradient >35 mmHg for NYHA class II, III, or IV, and severe (4+) PR with RV dilatation or dysfunction, or mean RVOT gradient >40 mmHg for NYHA class I.
149 patients were followed for a median of 8.4 years (5.4–10.1), with 102 patients having completed the 5-year follow-up assessment, and 58 patients having completed the 10-year follow-up assessment.
Estimated 10-year survival was 90% (79%–96%), with 5 of 11 deaths related to endocarditis. Estimated 10-year freedom from TPV dysfunction (RVOT reoperation, catheter reintervention on TPV, or ≥moderate PR and/or mean RVOT gradient >40 mm Hg) was 53% (40%–65%) and was significantly shorter in patients ≤21 years of age at implant (Figure 1).
Figure 1. Kaplan-Meier curves showing estimated freedom from mortality by age (A), overall freedom from TPV dysfunction (B), and freedom from TPV dysfunction by age (C).
Estimated 10-year reintervention-free survival was 55% (45%–63%), freedom from any TPV reintervention was 60% (47%–71%) and freedom from RVOT reoperation was 79% (67%–87%). On multivariable regression analysis, risk factors for reintervention were age ≤21 years, non-stented BPV/RVOT conduit, stenosis as primary indication for TPV replacement (TPVR), more prior open-heart surgeries and higher post-implant RV-pulmonary artery peak-to-peak gradient.
Concerningly, 28 patients (19%) had endocarditis during follow-up. At 10 years, estimated freedom from TPV-related endocarditis was 81% (69%–89%), with an annualized rate of 2.0% per patient-year, and estimated freedom from any endocarditis was 76% (63%–85%), with an annualized rate of 3.0% per patient-year.
Freedom from major stent fracture at 10 years was 84% (70%–92%), unchanged from the 85% (78%–91%) rate at 5 years. Other significant outcomes included mean RVOT gradient <20 mmHg, ≤3% of patients with >mild PR, and ≥75% of patients in NYHA class I (vs. 14% pre-TPVR) over the entire study period.
This extended trial fills an important knowledge gap as it reports on the longest median follow-up of TPVR with the Melody valve. It shows survival and freedom from reintervention rates similar to surgical pulmonary valve replacement with a RVOT conduit in a recent study with comparable median follow-up.1 Not surprisingly, it identifies TPVR in younger patients with a smaller RVOT conduit or BPV as a risk factor for reintervention. Finally, it establishes endocarditis as a serious concern and a main cause of mortality, being unfortunately underpowered to ascertain its risk factors.
- Lewis, M.J., Malm, T., Hallbergson, A. et al. Long-Term Follow-Up of Right Ventricle to Pulmonary Artery Biologic Valved Conduits Used in Pediatric Congenital Heart Surgery. Pediatr Cardiol (2022). https://doi.org/10.1007/s00246-022-02956-3
