As transcatheter heart valve replacement (TAVR) gains momentum as a viable alternative to open heart surgery for high-risk patients with severe aortic stenosis (AS), a new study shows that increasing wait times could make the procedure less effective for the individuals who need it most.Researchers at the University of Toronto and the Institute for Clinical Evaluative Sciences in Toronto used a mathematical modeling system to simulate the results from a previous TAVR trial with increased wait times. Although TAVR resulted in fewer deaths for inoperable patients regardless of wait time, the benefits of the procedure decreased dramatically when it was delayed, according to study results published in the Canadian Journal of Cardiology. In high-risk surgical candidates with TAVR wait times beyond 60 days, TAVR was less effective compared with conventional surgery, researchers said. "Our findings have implications for care delivery to severe AS patients who are TAVR candidates," said Dr. Harindra Wijeysundera, lead investigator on the study. "The clinical decision of when high-risk surgery is preferable over TAVR should incorporate the program's current TAVR wait time and the associated potential wait-time mortality.Creating such benchmarks for appropriate wait times should be a priority." However, not all physicians agree with the study's findings. Dr. John Webb and colleagues from the Centre for Heart Valve Innovation at St Paul's Hospital in Vancouver, said the analysis by Wijeysundera and her team is based on relatively old data that do not accurately reflect current patients or improved clinical outcomes. Still, "[o]ngoing close monitoring of the true wait times, adverse events, and long term outcomes will inform a much needed thoughtful evaluation of evidence-based benchmarks for waiting for TAVR," the physicians conceded in an accompanying editorial.The study's results could mean big things for companies vying for a place in the TAVR playing field, as devicemakers tout their product's superiority. In March, Edwards Lifesciences ($EW) Sapien XT device beat out Medtronic's ($MDT) CoreValve in the first head-to-head comparison of the companies' competing TAVR products. Medtronic bounced back in April with new data showing that its CoreValve device reduced the rate of death or major stroke in extreme-risk individuals with severe aortic stenosis. Last month, the companies settled their ongoing TAVR patent feud, allowing both CoreValve and Sapien XT to remain on the market. Medtronic and Edwards aren't the only device outfits with their eye on TAVR.In April, Boston Scientific ($BSX) celebrated positive study results from for its Lotus transcatheter heart valve system which found that 85% of patients had no paravalvular aortic regurgitation after being outfitted with the device. Last month, St. Jude ($STJ) completed the first U.S. implants of its transcatheter aortic system, moving the company one step closer to winning stateside approval for its product.Source: FierceMedicalDevices