OBJECTIVES: Many surgeons develop unique techniques for unmet needs for right ventricular outflow reconstruction to resolve pulmonary regurgitation after corrective surgery for congenital heart diseases. Expanded polytetrafluoroethylene (ePTFE) stands out as a reliable synthetic material, and clinical results with handmade ePTFE valves have been promising. This review focuses on the historical evolution of the use of ePTFE in pulmonary valve replacement and in the techniques for pioneering the translation of the handmade ePTFE trileaflet design for the transcatheter approach. METHODS: We searched for and reviewed publications from 1990 to 2020 in the Pubmed database. Nineteen clinical studies from 2005 to 2019 that focused on ePTFE-based valves were summarized. The evolution of the ePTFE-based valve over 3 decades and recent relevant in vitro studies were investigated. RESULTS: The average freedom from reintervention or surgery in the recorded ePTFE-based valve population was 90.2% at 5 years, and the survival rate was 96.7% at 3 years. CONCLUSIONS: Non-inferior clinical results of this ePTFE handmade valve were revealed compared to allograft or xenograft options for pulmonary valve replacement. Future investigations on transferring ePTFE trileaflet design to transcatheter devices should be considered.

Background: Extracorporeal membrane oxygenation (ECMO) has been proven effective in life support for patients with refractory cardiopulmonary failure. Deteriorating patients who have removed their first ECMO support and required second or more courses of ECMO support have rarely been discussed. Methods and Results: All the records of the patients who experienced at least 2 courses of ECMO during single admission were retrieved. Survival was defined as survival to discharge. Demographic data and clinical information were compared between survival and nonsurvival groups. There were 86 patients who received at least 2 courses of ECMO in the 20-year database, and 27 (31.3%) were <18 years old. Of them, 87.3% received 2 runs of ECMO, 10.4% 3 runs, and 2.3% 4 runs. Overall survival rate was 30.2%. The survival rate for patients with 2 runs of ECMO was 33.3% (25 out of 75), 11.1% (1 out of 9) for 3 runs, and 0% (0 out of 2) for 4 runs. Multivariate analysis revealed that only ARF with hemodialysis was the independent risk factor. Conclusions: The decision to perform repeated ECMO implantation is a complex and difficult process. Despite the arguments debating the consumption of resources and increased complications, there are still nearly 1 out of 3 patients who will survive to discharge. More than 2 courses of ECMO may be carefully considered for further rescue.

OBJECTIVES: Handmade trileaflet expanded polytetrafluoroethylene valved conduit developed using the flip-over method has been tailored for pulmonary valve reconstruction with satisfactory outcomes. We investigated the in vitro performance of the valve design in a mock circulatory system with various conduit sizes. In our study, the design was transformed into a transcatheter stent graft system which could fit in original valved conduits in a valve-in-valve fashion. METHODS: Five different sizes of valved polytetrafluoroethylene vascular grafts (16, 18, 20, 22 and 24 mm) were mounted onto a mock circulatory system with a prism window for direct leaflets motion observation. Transvalvular pressure gradients were recorded using pressure transducers. Mean and instant flows were determined via a rotameter and a flowmeter. Similar flip-over trileaflet valve design was then carried out in 3 available stent graft sizes (23, 26 and 28.5 mm, Gore aortic extender), which were deployed inside the valved conduits. RESULTS: Peak pressure gradient across 5 different sized graft valves, in their appropriate flow setting (2.0, 2.5 and 5.0 l/min), ranged from 4.7 to 13.2 mmHg. No significant valve regurgitation was noted (regurgitant fraction: 1.6–4.9%) in all valve sizes and combinations. Three sizes of the trileaflet-valved stent grafts were implanted in the 4 sizes of valved conduits except for the 16-mm conduit. Peak pressure gradient increase after valved-stent graft-in-valved-conduit setting was <10 mmHg in all 4 conduits. CONCLUSIONS: The study showed excellent in vitro performance of trileaflet polytetrafluoroethylene valved conduits. Its valved stent graft transformation provided data which may serve as a reference for transcatheter valve-in-valve research in the future.