Registry Provides Support for Use of MitraClip in Lower-Risk Patients
LONDON, England—Regardless
of surgical risk, patients treated with transcatheter mitral valve repair
achieve similar reductions in mitral regurgitation (MR) and improvements in
functional class at 1 year, according to data from a registry study presented
September 1, 2015, at the European Society of Cardiology Congress.
Saibel Kar, MD, of
Cedars-Sinai Medical Center (Los Angeles, CA), presented data from EVEREST II
REALISM, a prospective, multicenter, continued access registry of 
the EVEREST II trial,
which assessed mitral repair with MitraClip (Abbott Vascular) vs surgery. The current
study included patients with high risk (n=189) and without high risk (n = 185)
for surgery. All had moderate-to-severe or severe (grade 3+ or 4+) degenerative MR; high risk was defined by an
STS score ≥ 12% or surgeon assessment based on prespecified high-risk factors.
Patients at high risk were older and had a higher incidence of baseline comorbidities, including CAD, congestive heart failure, moderate-to-severe renal disease, diabetes, prior MI, and prior cardiovascular surgery compared with those with lower risk. High-risk patients also were more symptomatic, with 79% being in NYHA class III/IV at baseline vs 50% of the non-high-risk patients.
Less Need for Surgery than Trial Participants
At 1 year, both groups had a high rate of survival, although it was better in the lower-risk group (90.8% vs 80.4%). Stroke rates were similar in both groups, and no device embolization occurred in either group. The proportion of patients in NYHA class I/II increased regardless of risk status.
Additionally, a high proportion of high-risk (82%) and lower-risk (78%) patients achieved and maintained MR reduction to ≤ 2+ at 1 year, accompanied by reductions in LV end-diastolic volumes.
Importantly, patients in the high-risk and lower-risk groups also had high rates of freedom from mitral valve surgery that were even greater than those in the EVEREST II randomized trial (97.8% and 89.9% vs 75.1%).
Dr. Kar attributed the difference in freedom from surgery between the registry groups and the trial to overcoming the learning curve, better case selection, and the use of more than 1 clip in many cases.
Some limitations of the registry data, he acknowledged, are that while they shed light on outcomes between different types of patients treated with MitraClip, they are exploratory and not powered to detect differences in outcomes between patients with various levels of risk.
Registry Gains
EVEREST II REALISM was initially meant to provide additional real-world data in support of the US premarket approval application for MitraClip, which ultimately received FDA clearance in October 2013 for treatment of symptomatic degenerative MR grade ≥ 3 in those at prohibitive surgical risk.
Moderator Randolph P. Martin, MD, of Piedmont Heart Institute (Atlanta, GA), said a question that always comes up with regard to treating lower-risk patients is whether some of them may have mixed pathology as opposed to strictly degenerative MR.
But Dr. Kar said based on the data from the registry, the predominant pathology in the non-high-risk group was degenerative MR.
Audience member and inventor of the MitraClip Frederick St. Goar, MD, of El Camino Hospital (Mountain View, CA), asked Dr. Kar after his presentation whether the data “give you the confidence to move forward with treating patients with non-high risk.”
Dr. Kar said that based on his extensive experience both in performing the procedure and in selecting patients, he would favor a move toward expanding the procedure to intermediate-risk patients first, as has been done with TAVR.
Source:
Kar S. The EVEREST II
REALISM continued access study one-year outcomes in patients with primary
mitral regurgitation. Presented at: European Society of Cardiology Congress;
September 1, 2015; London, England.
Disclosures:
- Dr. Kar reports receiving research grants from Abbott Vascular, Boston Scientific, CardiAQ, and Cardiokinetix and serving as a consultant for Abbott Vascular, Boston Scientific, and Caisson.
Related Stories:
L.A. McKeown is a Senior Medical Journalist for TCTMD, the Section Editor of CV Team Forum, and Senior Medical…
Read Full Bio
Comments