Synopsis: ACC/AHA Guidance on Management of Secondary Mitral Regurgitation

The American College of Cardiology and the American Heart Association recently updated their joint guideline for managing patients with valvular heart disease. The full document is published in Circulation.

In JAMA, Sameer Hirji, MD, MPH, and Tsuyoshi Kaneko, MD, of the Division of Thoracic and Cardiac Surgery at Brigham and Women’s Hospital, and colleagues summarize the revised recommendations about caring for patients with secondary mitral regurgitation (SMR) now that transcatheter edge-to-edge mitral repair (TEER) has emerged as a treatment option.

Medical Therapy

Patients with chronic severe SMR (whether symptomatic or not) and heart failure with reduced left ventricular ejection fraction (LVEF) should receive standard heart failure goal-directed medical therapy: angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, beta-blockers, aldosterone antagonists and/or sacubitril/valsartan. Biventricular pacing should be added as indicated.

This is a class 1 (strong) recommendation. It is based on data from several randomized clinical trials showing that medical therapy reduces left ventricular (LV) volume in many patients, which reduces SMR severity.

Transcatheter Edge-to-Edge Mitral Repair

The guideline concludes TEER is reasonable for patients who have appropriate anatomy and persistent symptoms (New York Heart Association class II–IV) from chronic severe SMR related to LV dysfunction (LVEF <50%) despite optimized medical therapy.

This recommendation was primarily based on the COAPT trial, reported in The New England Journal of Medicine, which linked TEER with reduced two-year rates of hospitalization due to heart failure, cardiovascular mortality and the composite. These findings were discordant with the results of MITRA-FR, also reported in NEJM.

The discrepancy between these similarly designed trials might be attributable to their different selection criteria. The COAPT criteria—less advanced SMR than in MITRA-FR and a requirement for optimized medical therapy—are now considered standard, so the data from that trial were used to support the addition of TEER as a class 2a (moderate-strength) recommendation in the guidelines.

Mitral Valve Surgery

The guidelines also include class 2a recommendations that mitral valve surgery is reasonable for:

  • Patients with severe SMR undergoing coronary artery bypass grafting for myocardial ischemia
  • Patients with severe persistent symptoms from chronic severe SMR, despite optimized medical therapy, who have either LV systolic dysfunction or preserved LV function with atrial annular dilation

The first of these recommendations is based on the randomized STICH trial (published in Circulation) and a limited number of observational studies. The other is based on evidence from nonrandomized trials, observational studies, registry studies and meta-analyses, which failed to show a survival benefit but suggest the potential for improvement in symptoms and quality of life.

Patient Counseling

TEER has been accepted as an option for the management of symptomatic chronic SMR based on trials conducted in carefully selected cohorts. Patients considering TEER should be informed that 38% of patients receiving this therapy either die or are rehospitalized for heart failure within one year, according to a medical society registry study reported in the Journal of the American College of Cardiology. Individualized patient selection remains vitally important.