Clinical trials of a nonsurgical method of aortic valve replacement showed fewer deaths over a one-year span versus valve implantation through surgery in high-risk patients with severe cases of aortic stenosis.
Results of a pivotal trial involving Medtronic's CoreValve, which implants a prosthetic valve through a catheter, were presented Saturday at the American College of Cardiology's annual scientific session in Washington and published online in the New England Journal of Medicine
. The study marks the first comparison between the new method and open heart surgery in patients who would have been likely to undergo surgical valve replacement.
A total of 747 patients with an average age of 83 years participated in the trial. Of those who underwent transcatheter valve replacement, all-cause mortality after one year was 14.2% compared with 19% for patients who underwent surgical replacement.
“This is the first prospective study of any device that suggests TAVR is superior to (surgery) in a predefined population of patients, and that's a provocative finding,” study co-principal investigator Dr. David Adams, professor and chairman of the Department of Cardiothoracic Surgery at Mount Sinai Medical Center said in a written release.
Transcatheter Aortic Valve Replacement was first approved for use by the Food and Drug Administration in 2011 in patients too sick for surgery. In January, Medtronic's CoreValve became the second prosthetic device approved for use. TAVR has been associated with quicker recovery times compared with surgery since the method does not require opening a chest to implant the valve.
In addition to the death rate, investigators found rates for heart attack and stroke were lower for TAVR patients, with the rate of occurrence at 20.4% compared with 27% for surgical patients.
A possible limitation to the study was the higher dropout rate found among patients assigned to surgery. A total of 40 patients opted not to undergo surgical replacement as opposed to four who decided not to get TAVR.
Though the results of the trial have the potential for expanded use of TAVR over surgery, its widespread implementation may still be years away because of the procedure's high cost. The price of a TAVR prosthesis is about $32,000, compared with $7,000 for a surgical valve.
TAVR and surgical vales replacement is typically used to treat aortic stenosis, when the heart's aortic valve narrows.Follow Steven Ross Johnson on Twitter: @MHsjohnson