The pulmonary stenosis. It is a congenital heart defect (present at birth), which occurs due to abnormal development of the fetal heart during the first 8 weeks of pregnancy.
It affects one out of every 8,000 newborns and ranks second among the most common congenital heart defects , comprising between 5 and 10% of all cases.
It consists of the inadequate development of the pulmonary valve (which separates the right ventricle from the pulmonary artery), which causes a narrowing of the valve or the duct that goes from the right ventricle of the heart to the pulmonary artery (pulmonary infundibulum). The pulmonary valve is formed, under normal conditions, by three fins that function as a one-way door, allowing blood to flow into the pulmonary artery, but not back, into the right ventricle.
When there is pulmonary stenosis, problems with the valve prevent the normal opening of these flaps, the blood has difficulty crossing it, and increases the pressure in the right ventricle, also limiting pulmonary blood flow.
Summary
[ hide ]
- 1 Alternative names
- 2 Types of pulmonary stenosis
- 3 Causes
- 4 Symptoms
- 5 Heart involvement
- 6 Treatment
- 7 Expectations (prognosis)
- 8 Complications
- 9 Sources
Alternative names
Stenosis of the pulmonary valve of the heart; pulmonary valve stenosis; pulmonary valve narrowing; pulmonary balloon valvuloplasty
Types of pulmonary stenosis
Pulmonary stenosis can present in various degrees of severity, classified according to obstruction to blood flow from the right ventricle. In children, these problems can include:
- A valve that only has one or two fins instead of three.
- A valve that has three fins that are partially attached.
- A valve that has three thick flaps that do not fully open.
Causes
In most cases, pulmonary stenosis occurs sporadically (randomly) with no clear reason for its development; The cause is unknown but is generally not inherited, so in no case is it the fault of the parents. The most common cause is a malformation (for unknown reasons) during fetal development, which results in a reduction or narrowing in or below the pulmonary valve. This defect can occur alone or with other heart defects.
Symptoms
- Abdominal distension
- Bluish discoloration of the skin ( cyanosis ) in some patients
- Chest pain
- Fainting
- Fatigue
- Low weight gain or developmental delay in babies with severe obstruction
- Breathing difficulty
- Sudden death
Patients with mild or moderate obstruction may be asymptomatic and symptoms may not occur until the disorder is severe. Symptoms, once they occur, can worsen with exercise or activity.
Heart involvement
In pulmonary stenosis, in the absence of associated short circuits, arterial oxygen saturation is normal, making it one of the most common cyanotic diseases (it does not cause blue skin coloration). However, in cases where the stenosis is severe, it causes peripheral cyanosis as cardiac output is decreased. If there is a patent oval hole or a defect in the atrial septum that allows a right-to-left shunt, neither hypocratism nor polycythemia will develop .
Treatment
Sometimes, treatment may not be required if the disorder is mild. When there are also other heart abnormalities, you can use medicine to:
- Aiding blood flow through the heart ( prostaglandins )
- Help the heart beat faster
- Prevent clots ( anticoagulants )
- Eliminate excess fluid ( diuretics )
- Treat abnormal heart rhythms and beats
Pulmonary balloon dilatation ( valvuloplasty ) can be used when no other heart defect is present. This surgery is done through an artery in the groin . The doctor passes a flexible tube ( catheter ) with a balloon attached to the end to the heart. The balloon expands the valve opening. Some patients may need heart surgery to repair or replace the pulmonary valve. The new valve can be made of different materials.
Expectations (prognosis)
Approximately one third of patients with mild stenosis improve, one third remains the same and another third worsens. The clinical outcome is good with successful surgery or balloon dilation. Other heart defects may also be a factor in the prognosis. Some valves can last decades. Others wear out and will need to be replaced.
Complications
- Cyanosis
- Death
- Heart failure
- Retrograde blood flow to the right ventricle (pulmonary regurgitation) after repair
- Right ventricular hypertrophy (enlargement)