Mitral Valve Repair

Dr. Sabet HashimIt would take some extraordinary mechanical engineering to create a more highly synchronized or more efficient organ than the human heart. 

The mitral valve regulates blood flow between the two chambers in the left heart (left atrium and left ventricle). It is replaceable  by a man-made prosthetic or animal tissue valve, but that should never be the first choice.

At the Heart & Vascular Institute, our goal is to repair, whenever possible, your own precious living valve.


Our results, and multiple studies, confirm that repair is better than replacement, with a reduced risk of complications, no blood thinners (blood can cling to an artificial valve, causing clots), better quality of life and greatly enhanced chances of a longer life.

The repair rate for patients at the Heart & Vascular Institute with leaking mitral valves is close to 100 percent. Our experience is an important part of that success. More than 40 years of research has determined that, for most complex procedures, the hospitals and surgeons who perform them most often have the best patient outcomes. Specifically, a study of mitral valve replacement published in May 2017 in the Journal of the American College of Cardiology found much higher survival rates – and a greater likelihood of valve repair than replacement – when the surgeon had performed the procedure at least 25 times each year. 

Since performing New England’s first mitral valve repair in 1984, I have completed more than 2,000 of these procedures while maintaining the largest mitral valve practice in the state.

I continue to seek new ways to reduce physical intrusion – with incisions now as small as 3 inches -- while minimizing the patient’s recovery period. Not all mitral valves are repairable, but always consult a surgeon experienced in mitral valve repair before agreeing to replacement surgery.

-- Introduction by Dr. Sabet Hashim, chairman of cardiac surgery and co-physician-in-chief of the Heart & Vascular Institute.

 

Causes/Symptoms/Risk Factors

What makes the mitral valve such an important component of a healthy heart? A properly functioning mitral valve, situated between the left atrium left ventricle, opens as the left atrium fills with blood. As the heart expands, blood flows into the heart’s main pumping chamber, the left ventricle. The mitral valve then closes as the heart contracts, pushing oxygenated blood into the body’s largest artery, the aorta. 

When the mitral valve doesn’t work as it should, however, your heart might not pump enough of the oxygen-rich blood to your body. 

Here are the three types of mitral valve disease: 

1. Mitral Valve Regurgitation: The most common heart-valve disorder, when blood leaks backward through the mitral valve and into the left atrium (the heart’s upper chamber) each time the left ventricle contracts. Blood, in effect, is moving in two directions because it’s also flowing from the ventricle through the aortic valve – the heart’s normal function that helps replenish the body with oxygen-rich blood. In this case, however, it’s not enough.    

Causes

A healthy mitral valve, with two flaps of tissue (leaflets), opens as blood flows from the left atrium to the left ventricle before closing to prevent backflow. Regurgitation occurs when a mitral valve that doesn’t close tightly allows blood to flow backward each time the heart beats. 

Symptoms

Sometimes none. But you might experience:

  • Rapid breathing.
  • Cough.
  • Fatigue.
  • Light-headedness.
  • A feeling that your heart is beating fast than usual.
  • Excessive urination at night.
  • Awaking shortly after falling asleep because of trouble breathing.

Risk Factors

  • A heart attack.
  • Coronary heart disease.
  • Infection of the heart valves.
  • Mitral valve prolapse. (See below.)
  • Age. (Normal wear-and-tear on the mitral valve.)

2. Mitral Valve Prolapse (also known as Barlow’s syndrome or click-murmur syndrome): When the mitral valve’s two flaps bulge back, or prolapse, into the left atrium, it’s usually a harmless malfunction that affects 2 percent to 3 percent of the general population. If the valve does not seal properly, however, some blood can flow back from the ventricle into the atrium (regurgitation).

Causes

Researchers have not found a precise cause of mitral valve prolapse, but most patients who have this condition were born with it. People with connective tissue disorders, such as Marfan syndrome, are more likely to experience mitral valve prolapse.

The prolapse, or bulging, is a byproduct of an abnormal mitral valve: A stretched opening or valve flaps that are too big, too thick or “floppy” (stretched tissue). 

Symptoms

Most people with mitral valve prolapse will never have to deal with symptoms, or a significant valve backflow, related to the condition.

Possible symptoms:

  • Shortness of breath.
  • Cough.
  • Migraine.
  • Fatigue.
  • Dizziness.
  • Anxiety.
  • Palpitations.
  • Chest discomfort.

Risk Factors

  • Connective-tissue disorders (such as Marfan syndrome).
  • Skeletal problems (Scoliosis).
  • A history of rheumatic fever.
  • Muscular dystrophy.
  • Graves’ disease (a type of hyperthyroidism).

3. Mitral Valve Stenosis (also known as mitral stenosis): A narrowing of the mitral valve opening, often scarred or stiffened, that restricts blood flow to the left ventricle from the left atrium. This condition, attributed to rheumatic fever, is rare in the United States 

Causes 

Rheumatic fever, a childhood disease now rare in the United States, can cause scarring that damages the mitral valve. This disease, a response to a streptococcal infection, encourages the immune system to attach healthy tissues in the joints and heart. 

It can cause inflammation of the:

  • Myocarditis (heart muscle).
  • Endocarditis (heart lining).
  • Pericarditis (heart membrane).

In the United States, most cases of mitral valve stenosis are concentrated among older adults who had rheumatic fever before antibiotics were more commonly prescribed. 

Other possible causes, though rare:

  • Congenital heart defects.
  • Excess calcium.
  • Blood clots.
  • Tumors.
  • Radiation treatment.

Symptoms 

  • Shortness of breath, especially during or after exercising.
  • Difficulty breathing when sleeping or lying down.
  • Fatigue.
  • Respiratory infections (bronchitis).
  • Palpitations.
  • Dizziness, fainting.
  • Chest discomfort.
  • Cough.
  • Severe headache or stroke-like symptoms. 

Risk Factors

  • Rheumatic fever.
  • Renal falilure (dialysis).
  • Atherosclerosis.
  • Radiation therapy. 

Note: Rheumatic fever, though rare in the United States, is still prevalent in developing nations. 

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Diagnosis/Treatment

Your doctor, using a stethoscope, might detect a problem with a heart valve during a routine physical examination.

Several tests can help a cardiologist diagnose coronary heart disease: 

Electrocardiogram: A device that measures the heart’s electrical activity, its rate and regularity. 

Echocardiogram: An ultrasound test that uses a transducer to send out high-frequency sound waves toward the heart. The device in a traditional echocardiogram, when moved over the chest and abdomen, turns the echoes of sound waves redirected from various parts of the heart into detailed images of organs, blood flow and tissues. A transesophageal echocardiogram, using a device inserted into your esophagus, gives a more detailed picture of your heart.

Stress Test: A measure of your heart rate as you walk on a treadmill that tells doctors if your heart works properly when required to pump more blood. 

Chest X-ray: A picture of the chest area, including the heart and lungs, captured by X-rays.

Cardiac Catheterization: Diagnostic tests and imaging using a flexible tube (catheter) your doctor threads to your heart from a blood vessel in your arm, upper thigh or neck.

Holter Monitor: A portable device worn for two days that records the heart’s electrical activity, including heartbeats. A patient who feels symptoms while wearing the device can press a button that records heart rhythms at that time.

Learn More: Mitral Valve

If You Have The Procedure: The Incision

Anterior Thoracotomy Incision

The anterior thoracotomy approach avoids cutting the sternal bone and instead utilizes a 2-inch horizontal incision lateral to the nipple. The chest is entered between the ribs in the fourth intercostal space. The use of long-shafted instruments and a magnifying camera allow for precise work on the mitral valve. Dr. Hashim favors this new approach over robotic surgery, as it uses the same incisions and access but provides for tactile feedback from the instruments as they navigate the tissues of the valve. 

The Mini Lower Sternotomy Incision

The mini lower sternotomy incision is a 3-inch vertical incision over the lower part of the sternum. This incision avoids the upper sternum and provides the patient in recovery with greater flexibility in movement of the upper chest, enabling for an early return to driving.

Submammary Incision

The submammary approach provides the same inside access as the mini lower sternotomy, but uses a 2-inch curvilinear skin incision located within the bra line. Dr. Hashim developed this technique to provide his female patients who require a lower sternotomy incision with optimal aesthetic results.