Chronic pulmonary heart disease (abbreviated as pulmonary heart disease) is a disease caused by increased resistance to pulmonary circulation and pulmonary hypertension due to chronic lesions of the lungs, thorax or pulmonary arteries, which in turn causes hypertrophy and enlargement of the right ventricle and even the development of right heart failure. Clinically, it is characterized by recurrent coughing and wheezing, coughing and sputum, cyanosis and edema.
Pulmonary hypertension is defined as a persistent increase in pulmonary artery pressure caused by various causes, and is defined as pulmonary hypertension when it exceeds the highest normal value. Normally, pulmonary artery pressure is 2.4-4.0/0.8-1.6 kPa (18-30/6-12 mm Hg) at quiet time, with an average pressure of 1.7-2.3 kPa (13-17 mm Hg). When the systolic pressure of the pulmonary artery exceeds 4.O kPa (30 mm Hg), the diastolic pressure exceeds 2.0 kPa (15 mm Hg) or the mean pressure is higher than 2.7 kPa (20 mm Hg), it is called pulmonary hypertension. The normal total pulmonary vascular resistance is 0.02-0.03 N. If it is greater than 0.03, it indicates increased resistance.
I. Among the many causes of pulmonary heart disease, chronic obstructive pulmonary disease is the most common. The causes of pulmonary hypertension due to chronic obstructive pulmonary disease include.
1, hypoxia interferes with vascular smooth muscle cell membrane potassium and sodium ion exchange and induces the release of vasoactive substances from mast cells, causing spasm of small pulmonary arteries.
2, Hypoxia can also lead to changes in pulmonary vascular configuration, resulting in hypertrophy of the middle membrane of small pulmonary arteries and muscularization of non-muscular fine arteries, which leads to increased resistance of pulmonary circulation and pulmonary hypertension.
3, Abnormal enlargement of the alveolar cavity, increase in lung volume, and increase in intra-alveolar pressure lead to pulmonary vascular compression, luminal narrowing, and increased vascular pressure.
4, The increase in lung volume strains some of the vessels causing them to break, the number of vessels decreases, and the total area of the vascular bed decreases. When the area of the vascular bed in the lung is reduced to 70% of the original, there will be an increase in pulmonary artery pressure.
5. Increased blood volume and increased blood viscosity, secondary to increased RBCs produced by chronic hypoxia, increased blood viscosity, increased resistance to blood flow, hypoxia can also increase aldosterone, water and sodium retention, which in turn increases pulmonary artery pressure.
Pulmonary heart disease develops slowly, and the clinical manifestations are mainly signs and symptoms of respiratory insufficiency and right heart failure that appear gradually in addition to the signs and symptoms of the original lung disease. Acute attacks of pulmonary heart disease can be triggered by cold, upper respiratory tract infection, acute attacks of chronic bronchitis, pneumonia and exertion. Each acute attack will further aggravate the damage of heart and lung function, and finally lead to respiratory and circulatory failure.
Diagnostic criteria.
X-ray diagnostic criteria: 1.
1. Dilatation of the right inferior pulmonary artery trunk: transverse diameter >15mm, ratio of transverse diameter to trachea >1.07, wider than normal by more than 2mm
2. Protrusion of the middle part of the pulmonary artery or its height >=3mm
3. Dilated central pulmonary artery and slender peripheral pulmonary artery, with significant contrast
4. Significant protrusion of the cone (45 degrees in right anterior oblique position) or cone height >=7mm
5, right ventricular enlargement
C. Electrocardiographic diagnostic criteria.
1, frontal mean electric axis >= +90 degrees (right-sided electric axis)
2, V1 R/S<=1
3. Severe cis-clockwise translocation V5 R/S<=1
4. RV1+SV5>1.05mV
5, aVR R/S<1 R/Q>=1
6, V1-3 showed QS, Qs, qr (except myocardial infarction)
7, pulmonary P wave (P wave hyperacute)
IV. Secondary conditions.
1. Limb conduction hypovoltage;
2. right bundle branch block
V. Treatment.
1, acute exacerbation period
(1) Control of infection should be early and adequate, active and effective. Sensitive antibiotics can be used according to the drug sensitivity results.
(2) Ventilate the airway and improve respiratory function. Correct hypoxia and carbon dioxide retention. Assist ventilation if necessary.
(3) Control heart failure. Patients with pulmonary heart disease usually have improvement in heart failure symptoms after active control of infection.
(1) Diuretics: reduce blood volume, reduce right heart load and reduce the role of swelling. In principle, it is advisable to use diuretics with light effects and small doses, such as hydrochlorothiazide and aminoglutethimide.
The application of diuretics will make the sputum sticky and not easy to be expelled, so patients with large and sticky sputum need to weigh the pros and cons. At the same time, the use of diuretics will make the blood concentrated and cause hypercoagulation, so attention must be paid to prevent thrombosis.
②Indications for the application of positive inotropic agents are: a. Patients with heart failure whose infection has been controlled, respiratory function has improved, and diuretics cannot get good efficacy and repeated swelling; b. Patients with right heart failure as the main manifestation without obvious infection; c. Patients with acute left heart failure. Cardiac stimulants are mostly used in small doses, about 1/2 or 2/3 of the conventional dose, and drugs with fast action and fast excretion are selected.
(3) Vasodilators are applied to reduce the anterior and posterior loads on the heart, reduce myocardial oxygen consumption and increase myocardial contraction.
(4) Control arrhythmias, which can be relieved or disappear after anti-infection, and selective drug therapy for persistence.
(5) Strengthen nursing care.
2.Relief period
In principle, comprehensive measures combining Chinese and Western medicine are used, aiming to enhance the patient’s immune function, remove triggering factors, reduce or avoid the occurrence of acute exacerbation period, hoping to gradually make partial or full recovery of lung and heart function. Such as long-term oxygen therapy, adjustment of immune function, etc.
3.Nutritional therapy
The caloric supply is at least 12.5KJ/Kg per day, of which carbohydrates should not be too high.