WASHINGTON – Transcatheter heart valves (THV) developed for the treatment of symptomatic aortic stenosis have been used off label for the treatment of native aortic valve regurgitation (NAVR), but registry data suggest that outcomes have been disappointing, according to a presentation at CRT 2018 sponsored by the Cardiovascular Research Institute at Washington Hospital Center.
“Although significant improvement was seen with newer-generation THV devices, TAVR [transcatheter aortic valve replacement] for NAVR is a challenging approach associated with limited procedural efficacy,” reported Danny Dvir, MD, a prosthetic heart valve specialist and assistant professor of cardiology at the University of Washington, Seattle.
He based these remarks on data generated by 254 patients in the Valve in Valve International Data Registry who underwent TAVR for the treatment of NAVR. The outcomes were stratified by device generation. Of those in the registry, 109 received a first-generation device, including a device that is now considered obsolete, and 145 were implanted with a second-generation device.Results improved substantially with second-generation devices. For example, Dr. Dvir reported that the rate of device success climbed from 47% to 82% while correct positioning climbed from 67% to 91%. The proportion of patients without moderate or severe aortic regurgitation after placement of the THV climbed from 69% to 96%.
These improvements were reflected in clinical outcomes at 30 days. When second-generation devices were compared with first-generation devices, there was a reduction in all cause mortality (8% vs. 17%) and cardiac mortality (7% vs. 12%). There were also reductions from first- to second-generation devices in noncardiac mortality (1% vs. 5%), valve-related dysfunction (10% vs. 29%), and proportion of patients in New York Heart Association class III or IV (13% vs. 18%).
The improvement in outcomes from first- to second-generation devices is encouraging, but Dr. Dvir indicated that the main message is that TAVR for NAVR is producing success rates that “are suboptimal” and “not comparable to those being achieved when the indication is aortic stenosis.” The reasons cannot be derived from these data, but he suggested that optimal sizing of the device for NAVR might be different than it is for aortic stenosis.
“I wonder if we should have better devices designed specifically for aortic regurgitation,” Dr. Dvir said.