What is the Mitral Valve?​

The mitral valve is located between the left atrium and the left ventricle and is composed of two flaps. Normally the flaps are held tightly closed during left ventricular contraction (systole) by the chordae tendineae (small tendon "cords" that connect the flaps to the muscles of the heart). In Mitral Valve Prolapse (MVP), the flaps enlarge and stretch inward toward the left atrium, sometimes "snapping" during systole, and may allow some backflow of blood into the left atrium (regurgitation). 
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What is Mitral valve Prolapse?

Mitral valve prolapse, also known as click-murmur syndrome, Barlow's syndrome, balloon mitral valve, or floppy valve syndrome, is the bulging of one or both of the mitral valve flaps (leaflets) into the left atrium during the contraction of the heart. One or both of the flaps may not close properly, allowing the blood to leak backward (regurgitation). This regurgitation may result in a murmur (abnormal sound in the heart due to turbulent blood flow). Mitral regurgitation (backward flow of blood), if present at all, is generally mild.

It is estimated that mitral valve prolapse occurs in less than 3 percent of the population.
How is Mitral Valve Regurgitation (including Mitral Valve Prolapse) Treated?

The standard of care for patients with symptomatic mitral regurgitation (including mitral valve prolapse) is mitral valve surgery repair or replacement.   
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What is Mitral Valve Repair?
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Mitral valve repair is the best option for nearly all patients with a mitral regurgitation (a leaking valve) and for many with a mitral stenosis (a narrowed valve).  When possible valve repair is preferable, because a person's own tissues are used.

Mitral valve repair can be performed minimally invasively and with a catheter (Mitraclip)
What are the advantages of mitral valve repair?
  • A significantly lower risk of stroke
  • A lower rate of infection.
  • Improved long-term survival with mitral valve repair.
  • After mitral valve repair, blood thinners are not required.
  • After a successful valve repair the need for reoperation is less than 5 in 100 at 20 years
What is the risk of mitral valve surgery?
​For asympotmatic patients undgoing mitral valve surgery, the risk of peri-operative death is significantly less than 1 in 100.  Furthermore, after a successful valve repair the need for reoperation is less than 5 in 100 at 20 years.
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What are the Causes of Mitral Regurgitation?
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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. This causes a stretching out of the valve leaflets and the chordae tendineae. The elongation of the valve leaflets and the chordae tendineae prevent the valve leaflets from fully coapting when the valve is closed, causing the valve leaflets to prolapse into the left atrium, thereby causing mitral regurgitation.

Ischemic heart disease causes mitral regurgitation by the combination of ischemic dysfunction of the papillary muscles, and the dilatation of the left ventricle that is present in ischemic heart disease, with the subsequent displacement of the papillary muscles and the dilatation of the mitral valve annulus.

Rheumatic fever and connective tissue disease (e.g. Marfan's syndrome and Ehlers Danlos Syndrome) are other typical causes of mitral regurgitation. 

Secondary mitral regurgitation is 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. It is also called functional mitral regurgitation, because the papillary muscles, chordae, and valve leaflets are usually normal.

​Acute mitral regurgitation is most often caused by infaction of the heart valve. Papillary muscle rupture or dysfunction, including mitral valve prolapse are also common causes in acute cases.
What is Mitral Valve Regurgitation?​

Mitral valve regurgitation (MR), also known as a leaking mitral valve, Barlow's syndrome, occurs when one or both of the flaps may not close properly, allowing the blood to leak backward (regurgitation). This regurgitation may result in a murmur (abnormal sound in the heart due to turbulent blood flow). Mitral regurgitation (backward flow of blood), if present at all, is generally mild.
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What are the symptoms of MR?

Depending on the severity of the leak, each individual may experience symptoms differently. Symptoms may include:

  • Weakness
  • Fatigue
  • Shortness of breath.​
  • Atrial Fibrillation and/or Palpitations
  • Chest pain 
  • The left atrium and/or left ventricle may become enlarged
  • Depending on the severity of the leak into the left atrium during systole (mitral regurgitation), the left atrium and/or left ventricle may become enlarged, leading to symptoms of heart failure. These symptoms include weakness, fatigue, and shortness of breath.​
How is MR Diagnosed?

Persons with MR often have no symptoms and detection of a murmur may be discovered during a routine examination.

MR may be detected by listening with a stethoscope revealing a a murmur. The murmur is caused by some of the blood leaking back into the left atrium. 

In addition to a complete medical history and physical examination, diagnostic procedures for MR may include any, or a combination, of the following:

  • electrocardiogram (ECG or EKG) - a test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle damage. 
  • echocardiogram (also called echo) - a noninvasive test that uses sound waves to produce a study of the motion of the heart's chambers and valves. The echo sound waves create an image on the monitor as an ultrasound transducer is passed over the heart. Echocardiography is the most useful diagnostic test for MVP. 

In some situations where symptoms are more severe, additional diagnostic procedures may be performed. Additional procedures may include:

  • stress test (also called treadmill or exercise ECG) - a test that is performed while a patient walks on a treadmill to monitor the heart during exercise. Breathing and blood pressure rates are also monitored.
  • cardiac catheterization - with this procedure, x-rays are taken after a contrast agent is injected into an artery to locate the narrowing, occlusions, and other abnormalities of specific arteries. In addition, the function of the heart and the valves may be assessed.