It’s completely predictable that as clinicians climb the experience curve with a new technology, so results improve. It’s reassuring to have it play out in practice however, as new data from the ADVANCE registry confirms that mortality rates with transcatheter aortic-valve implantation (TAVI) have dropped steadily since the devices’ earliest clinical trials. The study’s principal investigator believes there is still some room for improvement.
At TCT 2012, Dr Axel Linke (University of Leipzig Heart Center, Germany) presented one-year results from the ADVANCE study of the Medtronic CoreValve. As reported by heartwire, ADVANCE includes 1015 TAVI patients treated between March 2010 and July 2011 at 44 centers in 12 European countries. The patients’ average age was 81, with a mean logistic EuroSCORE of 19.2.
Linke pointed out that the mortality rates seen in ADVANCE compare very favorably with the 24.2% one-year all-cause mortality in the TAVI patients in the PARTNER A pivotal trial of the Edwards Sapien TAVI system. They also are in line with the one-year results from the SOURCE registry with Sapien, where one-year survival was 76.1% in the overall cohort (although survival was higher in the transfemoral subgroup, at 81.1%). The latest results are also better than those seen in registries just a few years ago. For example, one-year mortality with CoreValve in the UK registry of 877 TAVI procedures between January 2007 and December 2009 was 21.7%.
These new ADVANCE data show “we have learned a lot with regard to the procedure. We’re preventing complications, and this affects long-term survival in a positive way,” Linke told heartwire.
Linke believes that TAVI mortality in this high-risk population will eventually level off around 15%. “It will be hard to come down lower than 15% because these patients have comorbidities—they die from pulmonary disease, infections, etc—that are not related to the procedure itself. So at some point, there will be a limit.”
If TAVI moves into a lower-risk population—such as the intermediate-risk population enrolling in the SURTAVI and PARTNER IIa trials—the mortality rate may drop even lower, but that is years away, Linke said.
“There is more room to grow with adjustment of devices. The next generations will address paravalvular leaks, and we’ve seen that paravalvular leaks affect mortality,” he said. Linke also believes that, in time, researchers and TAVI operators can reduce the one-month mortality rate with TAVI in high-risk patients to around 2%, which is the rate seen in less sick patients with conventional surgery, he said. “I hope that when we’re as good as conventional surgery at 30 days [and reduce paravalvular leaks], we’ll be as good as conventional surgery at one year.”
References: Linke A. The ADVANCE TAVR registry. TCT 2012; October 22, 2012; Miami, FL.
Medtronic. New study results show high survival rates and improved quality of life for patients with Medtronic CoreValve system (press release)