Quality of life, functional outcomes improved at 1 year in MitraClip postapproval study

SAN DIEGO — Use of the MitraClip transcatheter mitral valve repair device significantly improved functional, quality-of-life and echocardiographic outcomes at 1 year in patients with degenerative mitral regurgitation, according to postapproval registry data presented at the Society for Cardiovascular Angiography and Interventions Scientific Sessions.

For this registry-based postapproval study (PAS-1) of the MitraClip device (Abbott Vascular), researchers evaluated data from the American College of Cardiology/Society of Thoracic Surgeons Transcatheter Valve Therapy (ACC/STS TVT) registry on the first 2,000 patients treated with the device in the United States since it was approved by the FDA for degenerative mitral regurgitation in 2013.

The mean age of patients was 80 years, 43.5% were women and the mean STS mitral valve replacement score was 10.9%. Additionally, at baseline, 85.6% of patients had NYHA functional class III/IV HF and 94.7% had a mitral regurgitation grade of at least 3+.

The implant rate was 97.1%, with 52.4% of patients requiring one clip, 39.2% requiring two clips and 5.5% requiring three clips or more.

At 1 year, survival was 78.1%, a rate that was on par with observations in other real-world registries, James Hermiller, MD, from the St. Vincent Heart Center of Indianapolis, said during a press conference. Additionally, freedom from stroke was 98.5%. The most common adverse events at 1 year were readmission for HF (6.5%) and mitral valve reintervention (2.4%).

Mitral regurgitation severity improved significantly after implantation of the device, Hermiller noted. At 1 year, mitral regurgitation grades were 1+ in 41% of patients and 2+ in 45.6% of patients, with a notable difference between baseline and 1 year in the proportion of patients who had a mitral regurgitation grade of 2+ or less (5.1% vs. 86.6%; P < .0001).

Additionally, more patients were classified as having NYHA I/II HF at 1 year vs. baseline (83.4% vs. 18.4%; P < .0001). Patients also had a 37.9-m increase in 6-minute walk test distance and a 30-point increase in Kansas City Cardiomyopathy Questionnaire QOL score (P < .0001) from baseline to 1 year.

The researchers also observed favorable changes in left ventricular volume and dimension, with a mean 8.5-mL reduction in LV end-diastolic volume (P = .0201) and a mean 0.2-cm reduction in LV internal diameter at end diastole (P < .0001) from baseline to 1 year after treatment.

These data show that MitraClip “provides meaningful benefits in these prohibitive-risk degenerative mitral regurgitation patients,” Hermiller said.

“The acute 1-year outcomes are consistent with other clinical and real-world high-risk patients,” he said. “The commercial use of the MitraClip device remains a safe and effective option for select patients, and the present study does not present any new concerns during the real-world follow-up of this device.” – by Melissa Foster

Reference:

Hermiller J. Late-Breaking Clinical Science II. Presented at: Society for Cardiovascular Angiography and Interventions Scientific Sessions; April 25-28, 2018; San Diego.

Disclosure: The study was funded by Abbott Vascular. Hermiller reports he is a consultant for and has received honorarium and institutional grants or research support from Abbott Vascular.