Congenital mitral valve anomalies
Normal heart and heart with mitral valve stenosis
Mitral valve stenosis, shown in the heart on the right, is a condition in which the heart's mitral valve is narrowed. This abnormal valve doesn't open properly, blocking blood flow coming into your left ventricle, the main pumping chamber of your heart. A normal heart is shown on the left.
Mitral valve prolapse and regurgitation
The mitral valve separates the two chambers (atrium and ventricle) of the left side of the heart. In mitral valve prolapse, the leaflets of the mitral valve bulge (prolapse) into the left atrium like a parachute during the heart's contraction. Sometimes mitral valve prolapse causes blood to leak back into the atrium from the ventricle, which is called mitral valve regurgitation.
Congenital mitral valve anomalies are defects present at birth (congenital) that affect the heart's mitral valve. The mitral valve is located between the heart's upper left chamber (left atrium) and lower left chamber (left ventricle).
Various types of mitral valve anomalies exist, including:
- Thickened, stiffened, deformed or fused valve flaps (leaflets)
- Abnormalities with the cords that support the valve, such as short and thick cords, cords attaching to a heart muscle near the mitral valve, or missing cords
- Heart tissue or heart muscle problems near the mitral valve
These mitral valve anomalies can cause the mitral valve to not function normally. Some mitral valve anomalies may lead to mitral valve stenosis, in which the flaps become thick or stiff or fuse together. This causes a narrowed valve opening and reduced blood flow from the left atrium to the left ventricle.
Other mitral valve anomalies may lead to mitral valve regurgitation, in which the flaps don't close tightly, causing blood to leak backward into the left atrium. Mitral valve regurgitation may also be caused by the flaps bulging backward into the left atrium as your heart contracts (mitral valve prolapse). In some cases, people may have both mitral valve stenosis and mitral valve regurgitation.
Some people may have more than one opening in the area of the mitral valve, a condition called double-orifice mitral valve. In these people, one or both of the openings is often either narrowed (stenotic) or leaking (regurgitant).
People with mitral valve anomalies also often have additional congenital heart defects.
Your doctor may review your signs and symptoms, discuss your medical and family history, and conduct a physical exam. Your doctor may listen to your heart with a stethoscope to check for a heart murmur, which can be a sign of mitral valve disease.
Congenital mitral valve anomalies are often diagnosed with an echocardiogram. An echocardiogram uses sound waves to produce video images of your heart in motion. This test can show the structure of the heart, the heart valves and blood flow through the heart. Doctors may use this test to evaluate whether mitral valve stenosis or mitral valve regurgitation is present.
Other tests, such as a chest X-ray or electrocardiogram, may also be conducted.
Your treatment depends on the severity of your condition and if you're experiencing symptoms. Doctors may monitor your condition with regular follow-up appointments. You may eventually need surgery to treat your condition.
Surgery may include:
Mitral valve repair. Your doctor may often recommend mitral valve repair when possible, as it preserves your heart valve and may preserve heart function. Surgeons will generally perform mitral valve repair in children.
To repair a mitral valve, surgeons may patch holes in a valve; reconnect valve flaps; separate valve flaps that have fused; separate, remove or reshape muscle near the valve; separate, shorten, lengthen or replace the cords that support the valve; or remove excess valve tissue so that the leaflets can close tightly. Surgeons may tighten or reinforce the ring around a valve (annulus) by implanting an artificial ring.
Mitral valve replacement. If the mitral valve can't be repaired, surgeons may perform mitral valve replacement. In mitral valve replacement, your surgeon removes the damaged valve and replaces it with a mechanical valve or a valve made from cow, pig or human heart tissue (biological tissue valve).
Biological tissue valves degenerate over time, and often eventually need to be replaced. People with mechanical valves will need to take blood-thinning medications for life to prevent blood clots. Your doctor will discuss with you the benefits and risks of each type of valve and discuss which valve may be appropriate for you.
Biological tissue valves and mechanical valves may be used in children and adults. The specific valve used is decided by the cardiologist, surgeon and family after evaluating the risks and benefits.
Children and adults who have had surgery for congenital mitral valve anomalies or who have congenital mitral valve anomalies will need lifelong care provided by doctors trained in congenital heart conditions, such as pediatric and adult congenital cardiologists. Children and adults will need regular follow-up appointments to monitor for any changes in their condition. In some cases, additional valve repair or replacement surgeries may need to be performed, such as re-repair or replacing a valve that no longer functions.