March 10, 2013 – The outcomes in PARTNER II were considerably better than the original PARTNER trial.
The PARTNER and PARTNER II trials continue to generate significant interest three years after their initial publications and continue to produce groundbreaking results that are changing how clinicians treat valve disease. In a late-breaking clinical trial session at the American College of Cardiology Scientific Sessions of 2013, researchers shared outcomes of the next-generation transcatheter valve system in patients who were not eligible for traditional heart valve surgery. Overall, there were similar outcomes between the two randomized groups (original system and next generation system), with improved procedural safety in the group that received the next generation system compared with the original system.
The DCRI served as the imaging principal investigator, and Duke conducted all echocardiography, electrocardiography, as well as clinical adjudications for PARTNER. The DCRI’s Pamela Douglas, MD, is the lead investigator for the core labs.
PARTNER (Placement of Aortic Transcatheter Valves) was the first randomized trial for valve implants. Valve implantation, as opposed to surgically replacing heart valves, has opened the door for minimally invasive valve repair surgery, similar to how stents allow for minimally invasive artery procedures. In the PARTNER trial, there were two cohorts; cohort B consisted of patients with severe aortic stenosis who were not candidates for open-heart valve surgery. These patients were able to undergo transcatheter aortic valve replacement (TAVR), and the initial PARTNER results found an absolute 20 percent reduction in one-year mortality rates. However, these patients had a high rate of serious complications after the TAVR procedure, including strokes, vascular events, and serious bleeding complications.
PARTNER II compared the original TAVR system, called SAPIEN, with the next-generation, much smaller system called SAPIEN XT in patients who were not suitable for valve surgery. Approximately 550 patients were randomized to receive one of these two systems. The late-breaking results of PARTNER II were presented Sunday.
There were similar outcomes at 30 days between the two groups of patients, and similar rates of all-cause mortality, disabling stroke, and repeat hospitalization between the two groups one year after the procedure. Researchers observed improved procedural safety in the SAPIEN XT group. The outcomes in PARTNER II were considerably better than the original PARTNER trial, indicating improvements in patient selection, as well as improved surgical experience as surgeons have gained more expertise and experience performing TAVR in the years since the PARTNER trial.
“The work on the PARTNER and PARTNER II trials is changing the face of medical care,” said Dr. Douglas. “Suddenly, patients who were not considered eligible for valve surgery have new treatment options, and the demand is greater than anyone thought. With the TAVR system, these patients can undergo a procedure and be home the next day.”
“The SAPIEN XT system has a 40 percent smaller size than SAPIEN,” continued Dr. Douglas. “With the original system, many of the patients in cohort B experienced strokes, bleeding, and tearing of blood vessels, which were not trivial outcomes. These systems will continue to improve, leading to better clinical outcomes. If you look at stents today, they are very different from stents that would have been used 50 years ago, and the same advances will be made in transcatheter valve replacements.”