Mitral Regurgitation

Mitral Regurgitation

Mitral regurgitation (MR), a valvular heart disease, is the abnormal leaking of blood through the mitral valve, from the left ventricle into the left atrium of the heart.

The heart has four chambers: two atria and two ventricles.

  • The right atrium receives oxygen-poor blood from the body and pumps it to the right ventricle.
  • The right ventricle pumps the oxygen-poor blood to the lungs.
  • The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle.
  • The left ventricle pumps the oxygen-rich blood to the body.

The mitral valve is composed of the valve leaflets, the mitral valve annulus (which forms a ring around the valve leaflets), the papillary muscles (which tether the valve leaflets to the left ventricle, preventing them from prolapsing into the left atrium), and the chordae tendineae (which connect the valve leaflets to the papillary muscles). A dysfunction of any of these portions of the mitral valve apparatus can cause mitral regurgitation.
Primary mitral regurgitationis due to any disease process that affects the mitral valve apparatus itself. The causes of primary mitral regurgitation include:

The most common cause of primary mitral regurgitation in the United States (causing about 50% of primary mitral regurgitation) is myxomatous degeneration of the valve.
Secondary mitral regurgitationis due to the dilatation of the left ventricle, causing stretching of the mitral valve annulus and displacement of the papillary muscles. This dilatation of the left ventricle can be due to any cause of dilated cardiomyopathy, including aortic insufficiency, nonischemic dilated cardiomyopathy and Noncompaction Cardiomyopathy.

Risk factors for mitral valve regurgitation (MR) include:

  • Age. Wear and tear of the mitral valve occurs over time, increasing the likelihood of blood leaking back into the atrium.
  • Having mitral valve prolapse.
  • Having had rheumatic fever, because it can cause scarring on the valve, resulting in incomplete closure.
  • Coronary artery disease (CAD). CAD may cause ischemia (reduced blood flow) or infarction (heart attack), which affects the valve's structure, leading to incomplete closure.

Treatment for chronic mitral valve regurgitation (MR) includes monitoring your heart function and symptoms, as well as treating symptoms as they develop. If MR becomes severe, the mitral valve will need to be repaired or replaced. Treatment for acute MR is immediate. Medicines and urgent surgery are usually necessary.


Less invasive techniques
Doctors are developing less invasive techniques to treat valve disorders, such as repairing or replacing mitral valves using percutaneous heart catheterization techniques and minimally invasive off-pump mini surgeries. These minimally invasive mitral valve procedures are currently being studied in clinical trials. These types of percutaneous surgeries not only reduce procedure time, but provide an option for patients that could not undergo the rigors of an open heart procedure.

Cardiosolutions’ Percu-Pro System uses a percutaneous technique that will significantly reduce or eliminate MR by introducing an implant into the heart valve to help stop the backflow of blood caused by a “leaky valve”. The Mitra-Spacer™ implant is delivered via a catheter inserted into the patient’s femoral vein. The structure of the native valve is not altered during the procedure; the implant is designed to fit inside each unique mitral valve. The implant is intended to be retrievable; the procedure is not a replication of any open cardiac procedure. The implant can be sized or adjusted to address the different etiologies of Mitral regurgitation.