Pulmonary valve stenosis is a condition in which a deformity on or near your pulmonary valve, the valve that influences the blood flow from your heart to your lungs, slows the blood flow. Adults occasionally have the condition as a complication of another illness, but mostly, pulmonary valve stenosis develops before birth as a congenital heart defect.
Pulmonary valve stenosis ranges from mild and without symptoms to severe. Mild pulmonary stenosis doesn't usually worsen over time, but moderate and severe cases may worsen and require surgery. Fortunately, treatment is highly successful, and most people with pulmonary valve stenosis can expect to lead normal lives.
Pulmonary valve stenosis signs and symptoms vary, depending on the extent of the obstruction. People with mild pulmonary stenosis usually don't have symptoms. Those with more significant stenosis often first notice symptoms while exercising.
Pulmonary valve stenosis signs and symptoms may include:
Heart murmur — an abnormal whooshing sound heard using a stethoscope, caused by turbulent blood flow
Shortness of breath, especially during exertion
Loss of consciousness (fainting)
When to see a doctor
Talk to your doctor if you or your child has:
Shortness of breath
If you have pulmonary stenosis or another heart problem, prompt evaluation and treatment can help reduce your risk of complications.
Pulmonary valve stenosis usually occurs when the pulmonary valve doesn't grow properly during fetal development. Babies who have the condition often have other congenital heart abnormalities, as well. It's not known what causes the valve to develop abnormally.
Normal pulmonary valve anatomy
The pulmonary valve is made up of three thin pieces of tissue called leaflets that are arranged in a circle. With each heartbeat, the valve opens in the direction of blood flow — into the pulmonary artery and continuing to the lungs — then closes to prevent blood from flowing backward into the right ventricle of the heart.
What happens in pulmonary valve stenosis
One or more of the leaflets may be defective or too thick, or the leaflets may not separate from each other properly. If this happens, the valve doesn't open correctly, restricting blood flow.
Other contributing conditions
Sometimes other medical conditions or having an artificial valve can cause the condition in older people.
Carcinoid syndrome. This syndrome — a combination of signs and symptoms, including flushing of the skin and diarrhea — results from the release of a chemical, serotonin, from growths called carcinoid tumors in the digestive system.
Rheumatic fever. This complication of an infection caused by streptococcus bacteria, such as strep throat or scarlet fever, may injure the heart valves.
Because pulmonary valve stenosis usually develops before birth, there aren't many known risk factors. However, certain conditions can increase your risk of developing pulmonary valve stenosis later in life, including:
Mild to moderate pulmonary valve stenosis generally doesn't cause complications. Severe pulmonary stenosis may be associated with the following:
Infection. People with structural heart problems, such as pulmonary stenosis, have a higher risk of developing bacterial infections in the inner lining of the heart (infectious endocarditis).
Heart-pumping problems. In severe pulmonary stenosis, the heart's right ventricle must pump harder to force blood into the pulmonary artery. Pumping of the right ventricle against increased pressure causes the muscular wall of the ventricle to thicken and the chamber within the ventricle to enlarge (right ventricular hypertrophy). Eventually, the heart becomes stiff and may weaken.
Heart failure. If the right ventricle is unable to pump efficiently, heart failure develops. This results in swelling of the legs and abdomen and can cause fatigue and shortness of breath.
Irregular heartbeat (arrhythmia). People with pulmonary stenosis are more likely to have an irregular heartbeat. Unless the stenosis is severe, irregular heartbeats associated with pulmonary stenosis usually aren't life-threatening.
Pulmonary valve stenosis is often diagnosed in childhood, but sometimes it isn't detected until later in life. If your doctor hears a heart murmur during a routine checkup and suspects pulmonary stenosis, he or she may then use a variety of tests to confirm the diagnosis.
Electrocardiogram. During this procedure, patches with wires (electrodes) are placed on your chest, wrists and ankles. The electrodes measure electrical activity in your heart, which is recorded on paper. This test helps determine if the muscular wall of your right ventricle is thickened (ventricular hypertrophy).
Echocardiography. Sound waves bounce off your heart and produce moving images that can be viewed on a video screen. This test is useful for checking the structure of the pulmonary valve, the location and severity of the narrowing (stenosis), and right ventricle function.
Other imaging tests. MRI and CT scans are sometimes used to confirm the diagnosis of pulmonary valve stenosis.
Cardiac catheterization. During this procedure, your doctor inserts a thin, flexible tube (catheter) into an artery or vein in your groin and weaves it up to your heart or blood vessels. A dye injected through the catheter makes your blood vessels visible on X-ray. Doctors also use cardiac catheterization to measure the blood pressure in the heart chambers and blood vessels.
Doctors generally use this test only if they suspect that you or your child will need balloon valvuloplasty, a procedure that can be done at the same time as cardiac catheterization.
Pulmonary valve stenosis is classified as mild, moderate or severe, depending on a measurement of the blood pressure difference between the right ventricle and pulmonary artery. Mild pulmonary stenosis doesn't usually require treatment, just routine checkups.
Depending on the degree of obstruction, more-serious cases may need either balloon valvuloplasty or open-heart surgery.
Balloon valvuloplasty. Using the small tube that was threaded through a vein in your leg to your heart for a cardiac catheterization, your doctor places an uninflated balloon through the opening of the narrowed pulmonary valve. He or she then inflates the balloon, widening the narrowed valve to increase blood flow, and then removes the balloon.
The most common side effect of a balloon valvuloplasty is blood leakage back through the pulmonary valve (valve regurgitation). As with most procedures, there is a risk of bleeding, infection or blood clots.
Open-heart surgery. When balloon valvuloplasty isn't an option, you may require open-heart surgery. During surgery, your doctor either repairs the pulmonary artery or valve or replaces the valve with an artificial valve. Repairs to other congenital heart defects can be made during the surgery, as well. There's a slight risk of bleeding, infection or blood clots associated with the surgery.
While there's little you can do to prevent pulmonary valve stenosis, you can take measures to ensure you won't develop complications of your condition and stop it from worsening.
In the past, people with heart valve problems were advised to take antibiotics before certain dental and surgical procedures to prevent bacteria from causing an infection of the inner lining of the heart (infective endocarditis).
However, the American College of Cardiology and the American Heart Association advise that antibiotics are no longer necessary for people who have only pulmonary stenosis. Instead, antibiotics are reserved for people at high risk of serious complications of infective endocarditis, such as those who have other heart conditions or artificial valves or who've had repair with prosthetic material.
If you've had your pulmonary valve replaced, you will still need preventive antibiotics before dental and other procedures.
Adopting a heart-healthy lifestyle decreases your risk of developing other types of heart disease, such as heart attack. Lifestyle changes to talk to your doctor about include:
Quitting smoking. Smoking and other tobacco use is a significant risk factor for heart disease. Try to avoid secondhand smoke, as well.
Eating a heart-healthy diet. Focus on eating a diet that's low in sodium, cholesterol and saturated fat. Try to eat more fruits and vegetables, fish, low-fat dairy products, whole grains, and lean meat.
Maintaining a healthy weight. Excess weight may make you short of breath and may complicate heart surgery if you ever need it. Keep your weight within a range recommended by your doctor.
Exercising. Physical activity may help to keep your body fit and may help you to recover faster if you ever need heart surgery. How long and hard you're able to exercise may depend on what level of activity triggers your symptoms, if any. Ask your doctor for guidance before starting any exercise program.
Seeing your doctor regularly. Establish a regular appointment schedule with your cardiologist or primary care provider. If you had treatment for pulmonary valve stenosis as a child, tell your doctors, even if it hasn't caused any problems for you as an adult.
Pregnancy generally isn't a problem for women who have mild to moderate pulmonary valve stenosis. If you have severe pulmonary valve stenosis, the risks of complications during labor and delivery are higher than those for women without the condition. If necessary, it is possible to undergo balloon valvuloplasty during pregnancy.