Coinvestigator Dr. Murat Tuzcu, vice chair of the department of cardiovascular medicine at the Cleveland Clinic, stressed that the results were accomplished only through unprecedented teamwork among cardiologists, surgeons, and imaging experts, who consulted on each case in the trial.
"I want to emphasize that if we fail to pay equal attention to what we have done in this trial after the device is approved, I don’t think we will be able to replicate the same results," he said.
Several speakers at the press conference noted the balancing act that all clinicians will face regarding public demand for the new procedure.
Dr. Michael Crawford, chief of clinical cardiology at the University of California, San Francisco, observed that centers will face substantial up-front costs in the adoption of TAVR, including hybrid surgical/interventional suites, and that this will restrict initial uptake to high-volume centers of excellence.
The 3.4% mortality rate represents an "amazing effort," particularly in the use of the larger, first-generation device, said invited discussant Dr. Martyn Thomas, clinical director of cardiothoracic services at St. Thomas’ Hospital, London. The delivery catheters used in PARTNER are sized at 22 and 24 French, which corresponds to an outside diameter of 7-8 mm. The size of catheters is down to 16-Fr in Europe, where more than 5,000 TAVR procedures have been done and where both the Edwards Lifesciences Corp.’s Sapien valve that was used in PARTNER and the Medtronic Inc.’s CoreValve are already on the market.
Recruitment began in February for the PARTNER II trial that evaluated the smaller Edwards Sapien XT device and the later generation NovaFlex delivery system among inoperable patients with symptomatic severe aortic stenosis. The trial is expected to enroll 600 patients, and is targeted for primary completion in December 2011.
When asked whether the advent of newer, thinner devices will mean adoption in patients with lower risk, Dr. Smith replied that the adoption of TAVR will "march steadily down the risk categories."
Edwards Lifesciences sponsored the trial. Dr. Smith and his coauthors reported no conflicts of interest.