Pulmonary stenosis is a narrowing of the outlet from the right ventricle or pulmonary artery valve, and is classified by severity.
What is pulmonary stenosis?
Pulmonary stenosis is a narrowing in the outflow tract between the right ventricle and the pulmonary artery. The pulmonary valve is located between the pulmonary artery and the right ventricle. It is through it that deoxygenated blood enters the lungs. Thus, the valve is a valve responsible for controlling blood flow. It is a congenital heart defect that occurs either in isolation or can be part of a complex heart defect. Overall, three different types of pulmonary stenosis can be distinguished:
- Subvalvular pulmonary stenosis: narrowing of the outlet from the right ventricle due to excess tissue
- Valvular pulmonary stenosis: involves the valve itself, in which case the valve leaflets are partially fused or thickened and the valve opening is not complete.
- Supravalvular pulmonary stenosis: narrowing above the valve and narrowing of the pulmonary artery.
The most common type here is valvular pulmonary stenosis, which affects more than 90 percent of cases.
Causes
In many cases, pulmonary stenosis is a congenital heart defect, although the causes are unknown. In some circumstances, however, a genetic predisposition may be responsible. It is also possible that the pulmonary valve is not fully formed during pregnancy. In addition, pulmonary stenosis may also occur in addition to a congenital heart defect or in the course of rheumatic fever or cancerous tumors in the digestive tract.
Symptoms, complaints, and signs
Symptoms of pulmonary stenosis vary widely and depend on the severity of the narrowing. If the narrowing is only very mild, there are usually no symptoms. In severe cases, there is shortness of breath (dyspnea), which is mainly observed when the heart is strained. In addition, those affected suffer from peripheral cyanosis, which means that the patients are not supplied with sufficient oxygen. The heart is unable to deliver enough oxygen-depleted blood to the lungs. As a result, the red blood cells, which are responsible for transporting oxygen and exchanging it for carbon dioxide, do not receive new oxygen. Thus, they are unable to release the carbon dioxide. Peripheral cyanosis can be detected by a blood test, in which case the level of carbon dioxide in the red blood cells is greatly increased. For the heart, the constant attempt to pump the blood through the heart valve means an extremely great effort. As a result, the blood presses on the heart muscle, which grows as it has to adapt to the pressure conditions. If the narrowing of the heart valve is very severe, it can also lead to heart failure. Other possible symptoms include fatigue, protruding abdomen, fainting and a bluish tinge to the skin.
Diagnosis and course of the disease
Pulmonary stenosis can be diagnosed in several ways. First, the doctor listens to the affected person with a stethoscope. This allows him or her to hear heart sounds, and in the case of pulmonary stenosis, a so-called split second heart sound may be heard, which is due to the narrowing. A murmur may also be heard as blood flows out of the ventricle, which is called a “systolic.” Very often, an ECG is also performed, and changes can be detected if the narrowing is severe. Another examination method is the echocardiogram. This is an ultrasound examination in which the physician can visualize the structure of the heart. The heart or the heart valves can be viewed on a monitor and the direction of blood flow can be determined with the help of a color Doppler. An enlarged right heart can also be seen in an X-ray. The pulmonary vessels, on the other hand, are only very faintly imaged, which is a sign that only a small amount of blood is being transported to the lungs through the narrowed heart valve. A so-called invasive method is a right heart catheter, which can provide very precise information about a possible heart defect. With the help of a catheter, it is possible to estimate the severity of the narrowing.To do this, the physician inserts a catheter into a vessel in the thigh and then advances the catheter to the heart, where the tip of the catheter can measure the pressures in the pulmonary artery and the heart chambers, respectively.
Complications
As a result of pulmonary stenosis, in most cases those affected suffer from heart problems or breathing difficulties. At the same time, the resilience of the affected persons also decreases significantly due to the disease and there is a permanent fatigue and also fatigue of the patients. The internal organs are also supplied with less oxygen due to pulmonary stenosis and can be damaged as a result. In the worst case, carbon dioxide poisoning also occurs in those affected. Because the heart must also carry an increased amount of blood, heart failure or other cardiac conditions can result. In the worst case, the affected person dies of heart failure. Usually, without treatment, the patient’s life expectancy is significantly reduced. The treatment of this disease can be done by surgical intervention. No particular complications occur in this process. However, the affected person can no longer perform strenuous activities or sports. Furthermore, the patient is also dependent on medication to prevent further symptoms. With successful treatment of pulmonary stenosis, life expectancy is not affected in most cases. A healthy lifestyle can also have a very positive effect on this disease.
When should you see a doctor?
Pulmonary stenosis must always be treated by a physician. In the worst case, it can lead to the death of the affected person, so early diagnosis and treatment always have a very positive effect on the further course of the disease. As a rule, pulmonary stenosis is manifested by shortness of breath. Especially during strenuous activities or sports activities, shortness of breath may occur, and the affected person may also completely lose consciousness. Cyanosis may also indicate pulmonary stenosis and should be investigated if it occurs over a long period of time and reduces the patient’s quality of life. Furthermore, persistent fatigue or a severely protruding abdomen also indicates the disease and must be examined by a physician. In the first place, the disease can be examined by a general practitioner or by a cardiologist. However, if there is an emergency or loss of consciousness, then an emergency physician should be called or the hospital should be visited.
Treatment and therapy
A commonly chosen method for treating pulmonary stenosis is to dilate the narrowed heart valve using a balloon. In this procedure, the balloon is placed at the same level as the pulmonary stenosis using a cardiac catheter and then inflated. This allows the altered heart muscle to regress. In the case of very severe stenoses, however, surgery may be necessary. In this operation, the pulmonary valve is reconstructed or a heart valve is implanted. Newborns suffering from severe pulmonary stenosis require intensive medical care. In addition, the physician may prescribe medications to facilitate blood flow. These include, for example, medications for cardiac arrhythmias, water pills to allow increased water excretion, blood thinners, and prostaglandins to improve blood flow.
Prevention
Because pulmonary stenoses are very often congenital heart defects, they cannot be prevented. However, those affected should lead a heart-friendly and healthy lifestyle and avoid cigarettes. A healthy diet and regular exercise are also important.
Aftercare
The different severities and causes of pulmonary stenosis lead to different forms of therapy. The spectrum of possible treatment ranges from dietary changes to balloon dilatation, insertion of a stent, and surgical replacement of the pulmonary valve in the right ventricle. The need for follow-up treatment and follow-up examinations is correspondingly differentiated. Starting from a milder form of pulmonary stenosis, the need for follow-up examinations arises above all. This serves to determine whether the severity of the stenosis has been permanently reduced or whether the disease continues to progress, so that further treatment or surgery is indicated.The most important diagnostic devices for follow-up examinations are stethoscope, ECG and the Doppler ultrasound device. Regular follow-up examinations are also recommended after balloon dilatation or endoprosthetic replacement of the pulmonary valve. As a follow-up examination, Doppler sonography is of particular importance. It can be used to monitor whether thickening of the heart wall of the right ventricle (hypertrophy) is regressing, which can be taken as an indication that the intended purpose of the therapy has been achieved. For control purposes, further follow-up examinations are recommended from time to time, since a renewed narrowing of the pulmonary valve often occurs initially without symptoms. There is a risk that the renewed narrowing of the pulmonary circulation may not be noticed until very late, which may complicate subsequent therapy.
