Syndrome pulmonary hypertension

The increase of pressure in system of pulmonary capillaries (pulmonary hypertension, hypertension) is often a secondary disease not directly related to vascular lesions. The initial conditions are not well understood, but proved the role of vasoconstrictor mechanism, thickening the walls of the arteries, fibrosis (seal tissue).

In accordance with the ICD-10 (International classification of diseases) coded only the primary form of pathology as I27.0. All secondary signs join as complications to the main chronic diseases.

The blood pressure in the pulmonary vessels is regulated by:

• Pressor receptors in the vascular wall;
• branches of the vagus nerve;
• the sympathetic nerve.

Extensive receptor zones are located in large and medium-sized arteries, in areas of branching in the veins. Spasm of the arteries leads to impaired blood oxygen saturation. And tissue hypoxia promotes the release into blood of substances that increase the tone and cause pulmonary hypertension.

Irritation of fibers of the vagus nerve increases blood flow through the pulmonary tissue. The sympathetic nerve causes a vasoconstrictor effect. Under normal conditions, their interaction is balanced.

The norm accepted indicators of pressure in the pulmonary artery:

• systolic (upper) — from 23 to 26 mm Hg.St.;
• diastolic — from 7 to 9.

Pulmonary arterial hypertension, according to international experts, starts with a top level of 30 mm Hg. article

Factors that cause hypertension in the pulmonary

The main factors of disease, according to the classification V. Parin, divided into 2 subspecies. Functional factors include:

• constriction of arterioles in response to low oxygen and high concentration of carbon dioxide in the inhaled air;
• the increase in minute volume of the passing blood;
• increased intrabronchial pressure;
• the increase in the viscosity of the blood;
• failure of the left ventricle.

In the anatomical factors include:

• complete obliteration (overlap of the lumen) of blood vessels by thrombus or embolus;
• violated the outflow of the area of the veins due to their compression by aneurysm, tumor, mitral stenosis;
• the change of circulation after the removal of the lung surgically.

What causes secondary pulmonary hypertension?

Secondary pulmonary hypertension occurs as a consequence of known chronic diseases of the lungs and heart. These include:

• chronic inflammatory disease of the bronchi and the lung tissue (pulmonary fibrosis, emphysema, tuberculosis, sarcoidosis);
• turacoena pathology in violation of the structure of the thorax and spine (ankylosing spondylitis, the consequences of thoracoplasty, kyphoscoliosis, Pickwick syndrome in obesepeople);
• mitral stenosis;
• congenital heart defects (e.g., cleft arterial duct, in the interatrial and interventricular septum);
• tumors of the heart and lungs;
• diseases associated with thromboembolism;
• vasculitis in the area of the pulmonary artery.

Classification according to the nature of the flow

Clinicians convenient to divide the hypertension in the pulmonary vessels in terms of development for acute and chronic forms. Such a classification helps to "combine" the most common causes and clinical course.

Acute hypertension is caused due to:

• thromboembolism of the pulmonary artery;
• expressed status asthmaticus;
• respiratory distress syndrome;
• sudden left ventricular failure (the fault of myocardial infarction, hypertensive crisis).

To chronic pulmonary hypertension lead:

• increased pulmonary blood flow;
• the increase resistance in small blood vessels;
• the increase in pressure in the left atrium.

A similar mechanism of development is typical for:

• defects of the interventricular and interatrial septum;
• patent ductus arteriosus;
• mitral valve;
• proliferation myxoma or thrombus in the left atrium;
• gradual decompensation of chronic left ventricular failure, for example, when coronary artery disease or cardiomyopathy.

To chronic pulmonary hypertension cause of the disease:

• hypoxic nature of obstructive diseases of the bronchi and lungs, prolonged oxygen deprivation at altitude, hypoventilation syndrome associated with wounds of the chest, breath hardware;
• mechanical (obstructive) in origin, associated with narrowing of the arteries — a reaction to a drug, all variants of primary pulmonary hypertension, recurrent thromboembolism, connective tissue disease, vasculitis.