Major Finding: At 2 years, the composite primary efficacy end point of freedom from death, MV surgery for valve dysfunction (for device patients) or reoperation (for surgery patients), and MR greater than 2+ at 12 months was met by 52% of the percutaneous group and by 66% of the surgery group.
Data Source: A prospective, multi-center, randomized controlled phase II trial of 279 patients with 3+ or 4+ mitral regurgitation.
Disclosures: Dr. Feldman reported consulting fees, honoraria, and research grants from Abbott Vascular. Dr. Stone reported consulting fees and honoraria from Abbott Vascular and numerous other pharmaceutical and device companies. Dr. Bolling reported no relevant disclosures.
NEW ORLEANS – The durability and safety of treating mitral regurgitation with a percutaneous device as compared with that of surgical repair or replacement persisted at 2 years, according to an updated analysis of the EVEREST II trial results presented at the meeting.
“Our fundamental finding is that outcomes are very stable between 1 and 2 years of follow-up,” Dr. Ted Feldman, principal investigator, announced at a press briefing.
“The Kaplan-Meier curves for mortality and reoperation remain literally and completely flat through that time period, and clinical outcomes are durable,” he said.
On the basis of data from the first year of the study, percutaneous repair with the MitraClip was safer than surgery, but surgery yielded more complete reduction in mitral regurgitation (N. Engl. J. Med. 2011;364:1395-1406).
The 2-year results, presented at the meeting, show that both approaches reduced mitral regurgitation, and meaningful clinical benefits persisted, said Dr. Feldman, who is director of the cardiac catheterization laboratory at the NorthShore University HealthSystem in Evanston, Ill.
Clinical outcome measures at 2 years' follow-up showed that mitral regurgitation grade and left ventricular volumes remained stable between 1 and 2 years in both groups. The inter-group comparison showed a more favorable reduction in mitral regurgitation and a greater reduction in left ventricular diastolic volume with surgery at 1 and 2 years, and no difference in systolic volume reduction.
Also, New York Heart Association (NYHA) functional class was stable between years 1 and 2.
“Interestingly, the intergroup comparison showed a more favorable NYHA class outcome at both years with the clip,” Dr. Feldman reported.
The safety profile continued to be favorable, as well. “We saw no percutaneous device embolization; no device fracture, erosion, or migration; and no additional occurrence of single leaflet device attachment,” he reported.
“Stability is the major message in the examination of 2-year outcomes,” Dr. Feldman said.
“The randomized trial represents our very early experience with the device. Our procedural rate was 86% in the trial but in the postrandomization registry is in the 96% range. We are certainly going to get better at doing this.”
At a panel convened to comment on the study results, Dr. Gregg W. Stone, professor of medicine at New York Presbyterian Hospital and Columbia University, New York, said that the follow-up analysis of EVEREST II is “very well done” and has, “for the most part, shown stability and fairly comparable mortality, though 22% of patients still need surgery if they take the route of the percutaneous option.”
Dr. Steven F. Bolling, professor of surgery at the University of Michigan, Ann Arbor, maintained that while EVEREST II “suffers a little from awkward analyses,” the results are promising, pending the right patient selection and longer follow-up.
Patients at high surgical risk and those with cardiomyopathy-associated MR would be the appropriate subset for further study in order to refine the optimal use of the device, said Dr. Bolling.
EVEREST II (Endovascular Valve Edge-to-Edge Repair Study) is a prospective, multicenter, randomized controlled phase II trial comparing the safety and efficacy of the MitraClip System with mitral valve surgery in the treatment of mitral regurgitation. The study enrolled 279 patients with 3+ or 4+ mitral regurgitation who were either symptomatic or were asymptomatic with a baseline left ejection fraction of 60%; 27% had functional mitral regurgitation and 73% had degenerative mitral regurgitation. Approximately half of the patients had NYHA functional class III or IV heart failure.
The patients were randomized 2:1 to receive the MitraClip device (n = 184) or mitral valve (MV) repair or replacement (n = 95). More than 90% of the study cohort was available for the 2-year analysis.
Outcomes through 1 year (primary safety and efficacy end points) were recently reported (N. Engl. J. Med. 2011; 364:1395-406), showing increased safety with the MitraClip device compared to surgery, but greater reduction in mitral regurgitation with surgery. At 30 days, major adverse events occurred in 15% of the percutaneous arm versus 48% of the surgical arm. Left ventricular function improved in both groups, as did NYHA) functional class and quality of life at 1 year.