Mitral Regurgitation

Basic Facts

  • The mitral valve separates the top and bottom chambers of the left side of the heart, the left atrium and left ventricle. 
  • In mitral regurgitation (MR) the mitral valve is not closing properly. This allows some of the blood being pumped out of the left ventricle to leak back into the left atrium. This mixes with the next round of blood coming in from the lungs, and is thus “regurgitated.” 
  • Typically occurs gradually over time.
  • May eventually lead to valve repair or replacement surgery.  

Usually there are no symptoms until the valve leak is more severe, because mitral regurgitation usually advances slowly over years, giving the body time to adjust.  

As it advances to severe, it typically leads to shortness of breath on exertion, resulting in decreased exercise tolerance. 

If it happens acutely, it is more likely to present with rapid atrial fibrillation, CHF, chest pain, and/or sudden shortness of breath. 

In the USA, mitral regurgitation is most commonly due to degenerative changes in the valve over time. However, there are other potential causes and risk factors such as: 

  • Mitral valve prolapse can lead to MR over time. 

  • Trauma or structural heart changes that can occur with cardiomyopathy or MI.  

  • Connective tissue disorders like Marfan and Ehlers-Danlos Syndrome.

  • Inflammatory disorders, such as lupus or scleroderma.

  • Mitral Regurgitation can be caused by bacterial infections of the valve (endocarditis), though rare in the USA. 

Your healthcare provider may hear a murmur in your chest with their stethoscope. In mitral regurgitation, this murmur is caused by the sound of blood “whooshing” through the leaky mitral valve. Other tests may include: 

  • ECG – measures the electrical activity of the heart, regularity of heartbeats, and screens for thickening of the heart muscle (hypertrophy) and/or heart-muscle damage. 
  • Echocardiogram – painless, noninvasive study that uses ultrasound waves to evaluate heart structure & function, including the heart valves, in real time.  
  • Cardiac catheterization - threading a small tube (catheter) up a blood vessel into the heart chambers to measure pressures across the valve and to inject dye during a moving X-ray to detect/measure the regurgitation. 
  • Follow prevention tips for a heart healthy lifestyle.
  • Control blood pressure, as high pressure increases wear and tear on the valve over time. 
  • Mild to moderate MR is followed with a “watch and wait” approach, with a visit and/or echo every 1-2 years.
  • For severe MR, the damaged valve is often repaired rather than replaced surgically. However, the type of procedure depends on the patient’s age, condition, and their specific anatomy.
  • Most replacement valves nowadays are made from animal tissue (bioprosthetic valves). 
  • Some may be made from metal (mechanical valves). 
  • If mitral valve surgery is not an option for a patient, we offer a procedure via a cardiac catheterization called MitraClip to reduce the amount of leak through the valve. 
  • Patients do not need antibiotics for dental visits for mitral regurgitation, unless it was due to prior endocarditis (infection in the heart) or surgery was performed on the heart valve(s).