Preliminary Results With a Novel Expanded Polytetrafluoroethylene-based Pulmonary Valved Conduit
Christopher W. Baird, Mariana Chavez, Carl L. Backer, Mark E. Galantowicz, and Pedro J. Del Nido
Take Home Points:
- A novel expanded polytetrafluoroethylene-based pulmonary valved conduit was tested with a prospective, multicenter, single-arm study.
- This preliminary evaluation suggested promising valve function with no thromboembolic, no infectious complications, no valve-related re-interventions, no valve-related adverse events or unexpected findings. Improved right ventricular volumes and encouraging hemodynamic performance were proved by CMRI and through current follow-up.
Commentary from Dr. Masamichi Ono (Munich, Germany), section editor of Congenital Heart Surgery Journal Watch:
Summary:
This is a prospective, multicenter, single-arm study from centers in the USA, reporting results after the implantation of a novel expanded polytetrafluoroethylene (ePTFE)-based pulmonary valved conduit. A total of 17 patients (52.9% male; median age, 12 years; range, 6 to 17 years) were included. One patient had left coronary compression after the implantation of this conduit and was replaced with a biological valved conduit in the operating room. There has been no mortality and 100% freedom from device-related re-interventions. During follow-up, no evidence of worsening valvular insufficiency/stenosis was observed. No patient developed thrombus, calcification, or endocarditis. Six-month postoperative cardiac magnetic resonance imaging in 11 patients suggests favorable right ventricular remodeling with no significant change in ejection fraction.
Comment:
Reconstruction of the RVOT and replacement of pulmonary valves in pediatric and adolescent patients with congenital heart diseases have been ongoing challenges, especially given the lack of a durable prosthesis that is adjustable to the patient’s growth needs and is free of infection risks. Current RVOT reconstruction is limited to cryopreserved homografts, decellularized homografts, bioprosthetic valved conduits, bioprosthetic valves, bovine jugular conduits, and hand-sutured ePTFE grafts. All current conduits pose fundamental limitations. ePTFE has good biocompatibility, and its microporous structure impedes cellular penetration and subsequent calcification. Yamagishi, et al reported that hand-made ePTFE valve conduits have shown improved durability and significantly reduced infection rates.
This novel ePTFE-based valved conduit was industry-manufactured. The study demonstrated the safety and feasibility of this conduit. In this study, only a 20 mm-sized valved conduit was tested. Further studies with other (smaller or larger) sizes are mandatory to prove the usefulness of this conduit. Long-term durability should be also proved in further follow-up studies.
Yamagishi et al developed an ePTFE valved conduit with a fan-shaped configuration consisting of a 0.1-mm-thick ePTFE membrane and bulging sinuses to improve valve mobility. They demonstrated the excellent results of the freedom from reoperation was 98.8% at 5 years and 93.8% at 10 years with a median follow-up period of 4.9 years.
This conduit has been developed based on their experiences. Therefore, the preliminary results with a novel ePTFE pulmonary valve conduit are quite promising. Continued surveillance of these patients will be performed to assess the performance of this valve over time, and further studies with small-sized conduits are desirable.
