Types of narrowing
The obstacle can be located at different levels. Most often, this is valvular stenosis, when the valve leaflets are fused together at the edges and form a dome with a small hole. Less commonly, the narrowing is located below the valve, in the outflow tract of the right ventricle, or above - in the trunk and branches of the pulmonary artery. Severity is determined by the pressure gradient measured by Doppler and the condition of the right ventricle. This determines whether intervention is needed or observation is sufficient.
- Valvular stenosis is the most common option
- Subvalvular (infundibular) stenosis
- Supravalvular and branch stenosis
- Mild degree - observation
- Moderate to severe - intervention
- May be associated with a septal defect
Causes and risk factors
The defect forms in the early stages of pregnancy, when the parts of the heart are formed. As a rule, a specific cause cannot be determined. Infections suffered by the mother, primarily rubella, taking certain medications, poorly controlled diabetes and alcohol in the first trimester increase the likelihood of birth defects. Pulmonary artery stenosis often occurs as part of genetic syndromes and together with other defects, so a child with this diagnosis is thoroughly examined.
- Violation of valve formation in the fetus
- Genetic syndromes
- Rubella and other infections in the mother in the first trimester
- Certain medications during pregnancy
- Poorly controlled maternal diabetes
- Presence of congenital heart defects in the family
Symptoms
With slight narrowing, the child grows and develops normally, and the only finding remains a systolic murmur to the left of the sternum. With moderate stenosis, fatigue and shortness of breath appear during exertion, and in children - during feeding. Severe stenosis in a newborn is manifested by cyanosis and requires emergency care. In adults, a long-term defect can manifest itself as heart failure, swelling of the legs and enlarged liver - signs of right ventricular failure.
- Systolic murmur over the pulmonary artery region
- Shortness of breath and rapid fatigue on exertion
- Difficulty feeding in infants
- Bluishness in severe form
- Dizziness and fainting on exertion
- Swelling of the legs and enlarged liver in adults
Diagnostics
The examination begins with examining and listening to the heart, after which echocardiography is prescribed - it shows the level and degree of narrowing, the thickness of the wall of the right ventricle, the pressure gradient and associated defects. An ECG reveals overload of the right sections, and a chest x-ray reveals a characteristic expansion of the pulmonary artery after narrowing. In newborns, pulse oximetry is performed on the arms and legs. Invasive research with catheterization is most often carried out simultaneously with the treatment procedure.
- EchoCG with Doppler gradient assessment
- ECG: signs of right ventricular overload
- Chest X-ray
- Pulse oximetry in newborns
- Cardiac catheterization during intervention
- Examination for associated defects
Treatment and observation
Mild stenosis usually does not progress and requires only periodic echocardiography. For moderate and severe narrowing, the main method is balloon valvuloplasty: a catheter with a balloon is inserted through the vessel to the valve and the fused leaflets are expanded. The procedure is low-traumatic and well tolerated, including in newborns. If the anatomy is not suitable for a balloon or the valve is grossly altered, surgical correction is performed. After the intervention, the child remains under the supervision of a cardiologist, since a repeat procedure may be necessary over time.
- Observation and control echocardiography for mild forms
- Balloon valvuloplasty as the method of choice
- Surgical correction for complex anatomy
- Supporting blood flow in newborns before intervention
- Prevention of infective endocarditis
- Long-term observation by a cardiologist
