Pulmonary Stenosis Definition, Reason, Symptoms, Treatment & Prevention
Definition
In the heart, blood flow from the right ventricle will flow to the lungs through the pulmonary artery. This blood flow will pass through the pulmonary valve, which is a valve that has three ‘leaves’ and generally functions in one direction. This allows blood to flow through the pulmonary arteries, but not back into the right ventricle from the heart.
Pulmonary stenosis is a term used to describe a condition in which the pulmonary valve is difficult to open (stenosis) so that blood flow from the right ventricle to the pulmonary artery does not run smoothly. This stenosis can be caused by narrowing of the area before or after the pulmonary valve, thickening of the pulmonary valve leaflets making it difficult to open, and part of the valve leaflets being partially attached.
Often, pulmonary stenosis is due to an anatomic abnormality resulting from congenital heart disease. Pulmonary stenosis can be found in 7–10 percent of cases of congenital heart disease. Therefore, this condition is generally diagnosed in childhood.
Symptom
In pulmonary stenosis, there is a blockage of blood flow from the right ventricle to the lungs. This blockage can cause the work of the right ventricle to pump blood to become heavier so that thickening of the heart muscle (hypertrophy) can occur. The greater the blockage, the greater the thickening of the heart muscle in the right ventricle.
Hypertrophy can lead to impaired right ventricular function. The result can be heart rhythm disturbances (arrhythmias), loss of energy, and fluid retention. Increased right ventricular pressure can cause blood to flow back into the right atrium, then into the veins that carry blood from the body to the right side of the heart.
Symptoms that may appear include:
- Heavy or fast breathing
- Difficulty breathing (gasping)
- Easily tired
- Fast heart rate
- Swelling (due to fluid retention) in the legs, face, eyelids, or stomach
- Dizzy
- Faint
- Chest pain
- cyanosis
It is important to remember that the symptoms that appear can vary. These symptoms can also be similar to symptoms due to other medical problems.
Reason
Pulmonary stenosis is caused by abnormal development of the pulmonary valve of the heart. Generally, this situation occurs at eight weeks of gestation. Many factors can play a role in this developmental disorder, however, it often occurs suddenly without a known cause.
Some types of congenital heart disease are also related to genetics, so it may be more common in certain families.
There are four types of pulmonary stenosis, namely:
- Valvar pulmonic stenosis: due to thickened or narrowed leaflets on the pulmonary valve
- Supravalvar pulmonic stenosis: due to narrowing of the pulmonary arteries in the area above the pulmonary valve
- Subvalvar (infundibular) pulmonic stenosis: due to thickening of the muscle in the area below the pulmonary valve, causing narrowing of the blood flow from the right ventricle
- Branch peripheral pulmonic stenosis: there is a narrowing of the right, left, or both pulmonary arteries
Diagnosis
To determine the diagnosis of pulmonary stenosis, a complete evaluation is required which is obtained from:
- Detailed anamnesis or medical interview: where the history of the disease, the signs and symptoms felt, the family history of heart defects can be identified.
- Physical examination: especially a complete cardiac examination to assess the presence of abnormal heart sounds (such as murmurs due to turbulence of blood flow).
- Investigations: for example chest X-rays, cardiac MRI, echocardiography, electrocardiography, cardiac catheterization, and so on.
Treatment
The treatment offered depends on the patient’s condition. In mild pulmonary stenosis, often no special treatment is needed.
If treatment is recommended, surgery will generally be offered to repair the pulmonary valve. Some of the types of procedures to consider are:
- Balloon dilatation or valvuloplasty
- Valvotomy
- Valvectomy
- Enlargement patches
- Pulmonary valve replacement