Pulmonary hypertension is a threatening pathological condition caused by a persistent increase in blood pressure in the vascular bed of the pulmonary artery. The increase in pulmonary hypertension is gradual, progressive in nature and ultimately causes the development of right ventricular heart failure, leading to the death of the patient. The most common pulmonary hypertension occurs in young women 30-40 years old, who suffer from this disease 4 times more often than men. The low-symptom course of compensated pulmonary hypertension leads to the fact that it is often diagnosed only in severe stages, when patients have heart rhythm disturbances, hypertensive crises, hemoptysis, attacks of pulmonary edema. Vasodilators, disaggregants, anticoagulants, oxygen inhalations, diuretics are used in the treatment of pulmonary hypertension.
Causes of pulmonary hypertension
Reliable causes of pulmonary hypertension have not been determined. Primary form is a rare disease with an unknown etiology. It is assumed that such factors as autoimmune diseases (systemic lupus erythematosus, scleroderma, rheumatoid arthritis), family history, oral contraception are related to its occurrence.
Many diseases and defects of the heart, blood vessels and lungs can play a role in the development of secondary form. Most often, secondary form is a consequence of congestive heart failure, mitral stenosis, atrial septal defect, chronic obstructive pulmonary diseases, thrombosis of pulmonary veins and branches of the pulmonary artery, hypoventilation of the lungs, coronary heart disease, myocarditis, liver cirrhosis, etc. It is believed that the risk of developing disease is higher in HIV-infected patients, drug addicts, people taking appetite suppressants. In different ways, each of these conditions can cause an increase in blood pressure in the pulmonary artery.
The development of pulmonary hypertension is preceded by a gradual narrowing of the lumen of the small and medium vascular branches of the pulmonary artery system (capillaries, arterioles) due to thickening of the inner vascular membrane – the endothelium. With severe damage to the pulmonary artery, inflammatory destruction of the muscular layer of the vascular wall is possible. Damage to the walls of blood vessels leads to the development of chronic thrombosis and vascular obliteration.
These changes in the vascular bed of the pulmonary artery cause a progressive increase in intravascular pressure. Constantly increased blood pressure in the pulmonary artery increases the load on the right ventricle, causing hypertrophy of its walls. The progression of pathology leads to a decrease in the contractility of the right ventricle and its decompensation – right ventricular heart failure (pulmonary heart) develops.
To determine the severity of pulmonary hypertension, there are 4 classes of patients with cardiopulmonary circulatory insufficiency.
- Class I – patients without impaired physical activity. Normal loads do not cause dizziness, shortness of breath, chest pain, weakness.
- Class II – patients, causing a slight violation of physical activity. The state of rest does not cause discomfort, however, the usual physical activity is accompanied by dizziness, shortness of breath, chest pain, weakness.
- Class III – patients, which causes a significant violation of physical activity. Minor physical activity is accompanied by dizziness, shortness of breath, chest pain, weakness.
- Class IV – patients, accompanied by severe dizziness, shortness of breath, chest pain, weakness with minimal exertion and even at rest.
Pulmonary hypertension symptoms
In the compensation stage, pulmonary hypertension can be asymptomatic, so the disease is often diagnosed in severe forms. The initial manifestations of pulmonary hypertension are noted with an increase in pressure in the pulmonary artery system by 2 or more times compared to the physiological norm.
With the development of this disease, unexplained shortness of breath, weight loss, fatigue during physical activity, palpitations, cough, hoarseness of voice appear. Relatively early in the clinic of pathology, dizziness and fainting may occur due to a violation of the heart rhythm or the development of acute hypoxia of the brain. Later manifestations of pulmonary hypertension are hemoptysis, chest pain, swelling of the legs and feet, pain in the liver.
The low specificity of the symptoms of pulmonary hypertension does not allow to make a diagnosis based on subjective complaints. The most common complication of pulmonary hypertension is right ventricular heart failure, accompanied by rhythm disturbance – atrial fibrillation. In severe stages of pulmonary hypertension, thrombosis of the arterioles of the lungs develops.
With pulmonary hypertension, hypertensive crises may occur in the vascular bed of the pulmonary artery, manifested by attacks of pulmonary edema: a sharp increase in suffocation (more often at night), a strong cough with sputum, hemoptysis, pronounced general cyanosis, psychomotor agitation, swelling and pulsation of the cervical veins. The crisis ends with the release of a large volume of urine of light color and low density, involuntary defecation. With complications of pulmonary hypertension, a fatal outcome is possible due to acute or chronic cardiopulmonary insufficiency, as well as pulmonary embolism.
Usually, patients who do not know about their disease go to the doctor with complaints of shortness of breath. Examination of the patient reveals cyanosis, and with prolonged pulmonary hypertension – deformation of the distal phalanges of the fingers in the form of “drumsticks”, and nails — in the form of “watch glasses”. With auscultation of the heart, the accent of the II tone and its splitting in the projection of the pulmonary artery are determined, with percussion – the expansion of the boundaries of the pulmonary artery.
Diagnosis of pulmonary hypertension requires the joint participation of a cardiologist and a pulmonologist. To recognize pulmonary hypertension, it is necessary to conduct a whole diagnostic complex, including:
- ECG – to detect hypertrophy of the right parts of the heart.
- Echocardiography – to examine the vessels and cavities of the heart, to determine the speed of blood flow in the pulmonary artery system.
- Computed tomography – layered images of the chest organs show enlarged pulmonary arteries, as well as concomitant pulmonary hypertension diseases of the heart and lungs.
- Lung x-ray – determines the bulging of the main trunk of the pulmonary artery, the expansion of its main branches and the narrowing of smaller vessels, allows you to indirectly confirm the presence of pulmonary hypertension in the detection of other lung and heart diseases.
Catheterization of the pulmonary artery and the right parts of the heart is performed to determine the blood pressure in the pulmonary artery. It is the most reliable method of diagnosing pulmonary hypertension. Through a puncture in the jugular vein, the probe is brought to the right parts of the heart and blood pressure in the right ventricle and pulmonary arteries is determined using a pressure monitor on the probe. Cardiac catheterization is a minimally invasive technique that practically does not involve the risk of complications.
Angiopulmonography is an X–ray contrast examination of the vessels of the lungs in order to determine the vascular pattern in the pulmonary artery system and vascular blood flow. It is carried out in a specially equipped X-ray room with the observance of precautionary measures, because the introduction of a contrast agent can provoke a pulmonary hypertensive crisis.
Treatment for pulmonary hypertension
The main goals in the treatment of pulmonary hypertension are: eliminating its cause, lowering blood pressure in the pulmonary artery and preventing thrombosis in the pulmonary vessels. The complex of treatment of patients includes:
- Administration of vasodilating agents that relax the smooth muscle layer of blood vessels (prazosin, hydralazine, nifedipine). Vasodilators are effective in the early stages of the development of pulmonary hypertension before the occurrence of pronounced changes in arterioles, their occlusions and obliterations. In this regard, early diagnosis of the disease and the establishment of the etiology of disease is of great importance.
- Reception of disaggregants and anticoagulants of indirect action that reduce blood viscosity (acetyl-salicylic acid, dipyridamole, etc.). With pronounced blood thickening, bloodletting is resorted to. Optimal in patients with pulmonary hypertension is the level of hemoglobin in the blood up to 170 g / l.
- Oxygen inhalation as symptomatic therapy for severe dyspnea and hypoxia.
- Taking diuretics for pulmonary hypertension complicated by right ventricular insufficiency.
- Heart and lung transplantation in extremely severe cases of pulmonary hypertension. The experience of such operations is still small, but it testifies to the effectiveness of this technique.
Prognosis and prevention
The further prognosis for already developed disease depends on its root cause and the level of blood pressure in the pulmonary artery. With a good response to the therapy, the prognosis is more favorable. The higher and more stable the pressure level in the pulmonary artery system, the worse the prognosis. With pronounced decompensation phenomena and a pressure level in the pulmonary artery of more than 50 mm Hg, a significant part of patients die within the next 5 years. Prognostically, primary form is extremely unfavorable.
Preventive measures are aimed at early detection and active treatment of pathologies leading to pulmonary hypertension.