Transcatheter mitral valve repair linked to reduced mitral regurgitation

WASHINGTON — Most patients from a real-world registry of transcatheter mitral valve repair procedures had low levels of mitral regurgitation after the procedure, according to data presented at the American College of Cardiology Scientific Session.

Paul Sorajja, MD, director of the Center for Valve and Structural Heart Disease at Minneapolis Heart Institute and cardiologist at Abbott Northwestern Hospital, Minneapolis, and colleagues analyzed acute, 30-day and 1-year outcomes of commercial use of the transcatheter mitral valve repair system (MitraClip, Abbott Vascular).

“Thus far, there have been over 40,000 patients treated worldwide,” he said. “To gain insight into that commercial experience, we undertook this study.”

Paul Sorajja

Sorajja presented patient and procedural characteristics and acute outcomes from 2,952 patients with mitral regurgitation (mean age, 82 years; 56% men) in the Society of Thoracic Surgeons/ACC Transcatheter Valve Therapy registry and 1-year events from linked CMS claims data for 1,867 of those patients.

For the acute outcomes, 92.8% of patients had a mitral regurgitation severity grade of 2 or less after the procedure, and the acute procedural success was 91.8%, Sorajja said.

In addition, 2.7% of patients died in the hospital, 1.5% had single leaflet device attachment and 85.9% were discharged home after a median length of stay of 2 days, showing overall positive outcomes consistent with previous datasets, Sorajja said.

The rate of 1-year outcomes were as follows: death, 25.9%; HF rehospitalization, 20.2%; composite of death and HF rehospitalization, 37.9%; repeat procedure with MitraClip, 6.2%; and mitral valve surgery, 2.1%.

According to Sorajja, at 1 year, compared with those with degenerative mitral regurgitation, those with functional mitral regurgitation had higher rates of death (31.2% vs. 24.7%; P = .028) and the composite of death and HF rehospitalization (49% vs. 35.7%; P = .002). He said the early results for COAPT, the landmark trial for MitraClip in functional mitral regurgitation, are promising and may prove a reliable alternative to surgery in treating the condition.

Severity of postprocedural mitral regurgitation was associated with risk for death at 1 year (grades 3 and 4, 48.9%; grade 2, 29.2%; grades 0 and 1, 21.7%; P < .0001), he said.

After adjustments, predictors of 1-year mortality included age per 5 years (P = .005), dialysis (P = .004), moderate or severe lung disease (P = .02), left ventricular ejection fraction per 5% (P < .0001), and residual mitral regurgitation grade (P for grade 3 or 4 vs. grade 2 = .004; P for grade 0 or 1 vs. grade 2 = .005).

“Our study demonstrates the acute effectiveness and safety of transcatheter mitral repair in the United States,” Sorajja said. “There is a subset of these patients who are high risk, who may suffer multiple comorbidities, and who have persistent risk for mortality as well as HF hospitalization at 1 year. There are certain clinical variables, and also the degree of [mitral regurgitation] reduction, which can help predict the reduction of those long-term adverse outcomes.” – by Erik Swain

Reference:

Sorajja P, et al. Featured Clinical Research II: Interventional. Presented at: American College of Cardiology Scientific Session; March 17-19, 2017; Washington, D.C.

Disclosure: The study was funded in part by a grant from Abbott Vascular. Sorajja reports financial ties with Abbott Vascular, Boston Scientific, Integer and Medtronic.