Abstract 19214: Does Melody Pulmonary Valve Replacement Improve Exercise Tolerance Over a Five-Year Period?
Introduction: Percutaneous Melody valve implant is an alternative to surgical valve replacement for right ventricular outflow tract (RVOT) conduit obstruction or insufficiency. However, the long-term benefits of Melody valve implant on exercise capacity remain undefined.
Hypothesis: Melody valve implant results in improvement of objective measures of exercise capacity.
Methods: As part of the phase I Melody valve clinical trial, 136 patients with congenital heart disease underwent serial cardiopulmonary exercise testing (CPET) prior to, 6 months after, and annually for 5 years at implanting centers. CPET was performed on a mechanically braked cycle ergometer. Assessment was performed with baseline pulmonary function testing and ventilation ratios measured at ventilatory anaerobic threshold (VAT).
Results: Mean age at Melody valve implantation was 22.4±0.9 yrs, range 7-53 yrs. There were sustained improvements in predicted maximum workload from 62% pre-implant to a peak of 72% 4 yrs post-implant (p=0.005). Improvements were demonstrated in the ventilatory equivalents for CO2 (VE/VCO2; p=0.01) and O2 (VE/VO2; p<0.001) at VAT. Maximal oxygen consumption (peak VO2) and peak heart rate were not significantly changed (p>0.05). There were significant improvements in forced vital capacity (75% pre-implant vs peak 81% at 4 yrs, p=0.02) and first second forced expiratory volume (73% pre-implant vs peak 78% at 4 yrs, p=0.01), with some decline in the spirometric values noted at 5 yrs. Observed improvements in measures of exercise capacity occurred primarily in the first 6 months post-implant.
Conclusions: Melody valve implant is associated with initial improvements in exercise tolerance and ventilation-perfusion matching at 6 months that were sustained throughout follow-up. Observed changes indicate improvement in restrictive lung physiology, which may be related to RV dilation prior to implant.
Author Disclosures: B. Priromprintr: None. M.J. Silka: None. J. Rhodes: None. A.S. Batra: Research Grant; Modest; Medtronic, Inc..
- © 2016 by American Heart Association, Inc.