Mitral Regurgitation (MR)

Mitral regurgitation refers to the leakage of mitral valve, which is a heart valve that controls blood flow between left atrium and left ventricle (see picture).




The main causes of mitral regurgitation (MR) are mitral valve prolapse and rheumatic heart disease. Dilated heart chambers resulting from heart attacks also cause MR.

In principle, corrective surgery should be performed before left ventricular (LV) chamber becomes dysfunctional and fails. Patients usually do not recover well after surgery if the contractile power of left chamber (LVEF) is < 40 percent before surgery. Therefore, doctors may recommend periodical echocardiography to assess left ventricular chamber and determine the need and timing of surgery.

If surgery is not indicated, many patients may benefits from several heart medications, especially hydralazine.

MR is often associated with atrial fibrillation, an irregularly irregular hear rhythm, which can result in formation of blood clots. Doctors may recommend conversion to normal heart rhythm or blood thinners to prevent risk of stroke.

According to 2007 guidelines by American Heart Association, patients with MR may not need antibiotic prophylaxis before dental or surgical procedures. However, those patients with artificial mitral valve still need antibiotic prophylaxis.