Cardiologists perform world’s first TAVR procedures with new fully retrievable valve
A new self-expanding transcatheter aortic valve replacement (TAVR) device designed to be retrievable and repositionable at 100% full deployment is associated with encouraging early safety and clinical outcomes, according to a first-in-human study published in The American Journal of Cardiology.[1]
The device in question is the Venus-PowerX TAVR valve developed by China-based Venus MedTech. It includes a wire-controlled mechanism that makes it possible to recapture even after full deployment. The device also features an hourglass-shaped frame and supra-annular porcine pericardial leaflets. Three radiopaque markets are included to assist operators when implanting the valve, and its sealing skirt was built to minimize the risk of paravalvular leak. In addition, parts of the Venus-PowerX TAVR valve were processed using proprietary anti-calcification and dry-tissue technologies to improve long-term durability and allow care teams to store it at room temperature.
“Current-generation self-expanding TAVR systems, which are partially retrievable and repositionable, have shown improved clinical performance in challenging anatomical scenarios,” wrote first author Zhengang Zhao, MD, a cardiologist at West China Hospital in Chengdu, China, and colleagues. “However, there is a risk of valve migration and malposition during final release, necessitating the implant of a second valve or conversion to open-heart surgery. The Venus-PowerX is a fully retrievable self-expanding TAVR system with adaptive seal and dry-tissue leaflets. It has been designed to optimize valve positioning, acute procedural results and long-term clinical benefits.”
Tracking early patient outcomes
This analysis represents the first time the Venus-PowerX valve has been implanted into human patients. A total of 25 patients with severe aortic stenosis were included in this analysis. All patients were treated at one of two facilities in China. The mean patient age was 75.3 years old, 52% of patients were women and 52% of patient presented with a bicuspid aortic valve.
Overall, 100% of TAVR procedures were successful. No major procedural complications were reported, and there were no cases of valve migration or embolization. Valve recapture at 80% partial deployment was attempted 32% of the time, and it was a success each time “without difficulty.” Valve retrieval at 100% deployment was attempted—and completed successfully—8% of the time. The overall technical success rate was 100%.
The implant process for the Venus-PowerX TAVR valve. The delivery system features a wire-controlled mechanism that enables recapture after 100% full deployment. Images courtesy of Zhao et al. and The American Journal of Cardiology.
After 30 days, device success was achieved in 88% of patients and 20% of patients required a permanent pacemaker. Risk factors for requiring a permanent pacemaker included right bundle branch block, a short membranous septum length below the annulus and the use of a 32-mm valve. There were no reports of stroke, myocardial infarction, clinically significant valve thrombosis, infective endocarditis or cardiovascular hospitalizations.
After one year, meanwhile, the overall survival rate was 96%. One patient did die of pneumonia three months following treatment. There were still no reports of stroke, myocardial infarction or cardiovascular rehospitalization.
“Between 30 days and one year, there was no further bleeding events or requirement for new permanent pacemaker implantation,” the authors wrote.
Zhao et al. noted that the mean aortic valve gradient dropped significantly from 56 mmHg to 11.6 mmHg. The mean effective orifice area improved from 0.6 cm2 to 1.8 cm2. One patient had moderate paravalvular leak.
The study's authors did note that much more research is still needed to track the safety and effectiveness of this device in larger patient populations.
Key features of this new-look TAVR valve
“The Venus-PowerX is a fully retrievable self-expanding system, designed for more controllable TAVR procedure,” the authors wrote. “The capacity to retrieve at full deployment could help achieve optimal valve placement while minimize valve migration or embolization. Optimal high implant has been associated with less paravalvular leak, lower risk of new-onset conduction disturbances and more circular expansion at the functioning level for durable valve performance.”
Other than its ability to be retrieved and repositioned at full employment, the one feature that stood out the most to Zhao and colleagues was the device’s dry-issue technology. This should help limit calcification, the group wrote, and make the valve more tolerant to “wear and fatigue.”
“Moreover, the valve has been pre-mounted, pre-packaged and sterilized at manufacturer, thus is ready for use off the shelf and does not need significant on-site valve preparation,” the group explained. “Rapid deployment TAVR, which could be life-saving in the setting of hemodynamic instability or under other emergent circumstances, is possible with the Venus-PowerX Valve. Additionally, as the device can be easily transported and stored, it also confers the potential of facilitating TAVR dissemination to resource-poor regions.”
Click here to read the full analysis.
Michael has more than 18 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.