Background
The Melody transcatheter pulmonary valve (TPV) Post-Approval Study demonstrated excellent 1-y performance in a real-world cohort with a high procedural success rate, excellent short-term TPV function, and low reintervention and reoperation rates. Intermediate and long-term follow-up results have not been reported.
Methods
This nonrandomized, prospective study at 10 US centers enrolled 131 patients with dysfunctional right ventricular outflow tract (RVOT) conduits with an indication for intervention from July 2010 to July 2012. Mean age was 20.1±9.8 y; 84 patients (64.1%) were ≤21 y; 87 patients (66.4%) were male. Patients were followed for 5 y.
Results
Ten patients were ineligible for implant, and 121 patients underwent catheterization. The TPV was implanted in 100 patients; the valve was explanted from 1 patient within 24 h. Mean follow-up for the remaining 99 patients was 4.5±1.3 y (range 0.2-6.2 y) with 65 patients completing 5-y follow-up. Two deaths occurred during follow-up (at >2 y and >4 y postimplant) and were not considered to be related to the device. However, 1 patient had endocarditis at the time of death. In all, there were 16 cases of TPV-related endocarditis in 13 patients; 9 cases were treated with antibiotics only, and 7 required surgery. Major stent fracture occurred in 6 patients, 5 of whom underwent conduit pre-stenting. Kaplan-Meier freedom from event rates at 5 y were as follows: all-cause death (n=121), 97.5%; major stent fracture (n=99), 93.0%; catheter reintervention (n=99), 92.8%; TPV-related endocarditis (n=100), 84.9%; and conduit reoperation (n=99), 82.4%. At 5-y follow up, the mean RVOT gradient on echocardiography was 17.2±12.1 mmHg (n=31), and the degree of pulmonary regurgitation (PR) was mild in 4/34 (11.8%) patients, moderate in 2 (5.9%), and severe in 1 (2.9%); the remainder had no/trace PR. Most patients (53/66, 85.5%) were in NYHA class I.
Conclusions
This real-world experience with the Melody TPV demonstrates continued excellent valve function and low reintervention and reoperation rates with a promising safety profile at 5 y following implantation. Endocarditis is, however, an important adverse outcome. Ongoing studies exploring long-term performance of the Melody TPV are necessary.