Relationships Among Conduit Type, Pre-Stenting, and Outcomes in Patients Undergoing Transcatheter Pulmonary Valve Replacement in the Prospective North American and European Melody Valve Trials

OBJECTIVES This study sought to evaluate the incidence of and risk factors for conduit and stent-related outcomes following transcatheter pulmonary valve replacement (TPVR). BACKGROUND Stent fracture (SF) and right ventricular outflow tract (RVOT) reintervention are among the most important adverse outcomes after TPVR using the Melody valve (Medtronic, Minneapolis, Minnesota). The conduit environment and conduit preparation practices vary among patients who undergo TPVR. METHODS Data from 3 prospective Melody valve multicenter studies were pooled and analyzed. All patients who had successful implant of a Melody valve that was present at hospital discharge comprised the study cohort; patients who had TPVR into a stentless conduit comprised the analysis cohort. SF was diagnosed using protocol-specified or clinical fluoroscopy or radiography, and classified as major or minor. RESULTS Of 358 patients who underwent catheterization with intent to perform TPVR, 309 were discharged with the Melody valve in place (study cohort) of which 251 patients had TPVR into a stentless conduit (analysis cohort). Median follow-up was 5 years. New pre-stents were placed in 68% of patients with a stentless conduit, and 22% received multiple pre-stents. At 3 years, freedom from any SF and major SF was 74 +/- 3% and 85 +/- 2%, respectively, and freedom from RVOT reintervention was 85 +/- 2%. New pre-stents were associated with longer freedom from SF and RVOT reintervention than was no pre-stent. CONCLUSIONS Risks of SF and reintervention after TPVR with a Melody valve were reduced by implantation of pre-stents, which has become standard practice. This study supports pre-stenting as an important component of TPVR therapy. (C) 2017 Published by Elsevier on behalf of the American College of Cardiology Foundation.