congenital pulmonary arteriovenous fistula
Introduction
Introduction to congenital pulmonary arteriovenous fistula Congenital pulmonary arterio-venous fistula (PAVF), also known as arteriovenous aneurysm, is a common congenital malformation. . About 1/3 of the patients have multiple lesions in the lung, which are dominantly inherited. The patients and their families are often accompanied by hereditary hemorrhagic telangiectasia (such as skin, mucous membrane, etc.), which can affect the gastrointestinal tract. Called Rendu-Osler-Weber disease. See also single non-familial disease. basic knowledge The proportion of illness: 0.001% Susceptible people: no specific population Mode of infection: non-infectious Complications: blood gas chest esophageal chest pain shock cerebral thrombosis brain abscess
Cause
Congenital pulmonary arteriovenous fistula
( 1) Causes of the disease
More common congenital malformations, embryonic pulmonary circulatory arteriovenous capillary anastomosis expansion, the formation of abnormal communication between the pulmonary arteries and veins, about 1/3 of patients with multiple lesions in the lung, is a dominant inheritance.
(two) pathogenesis
Congenital pulmonary arteriovenous fistula is multiple (66%) or single (34%), mostly located in the inferior lobe of the two lungs or in the subpleural pleura of the lungs. It is spherical in the naked eye, dark red, 1mm to several centimeters in diameter, but The microscopic lesions can only be confirmed by microscopic examination by lung biopsy. The microscopic examination shows a thin-walled vascular cavity, the abnormal expansion is cystic, the wall tissue is degenerated, and the dilated afferent artery is connected with the efferent vein.
Prevention
Congenital pulmonary arteriovenous fistula prevention
The disease belongs to the more common congenital malformation, which causes the cause of developmental malformation to be unclear. It may have certain correlation with environmental factors, genetic factors, dietary factors, and mood and nutrition during pregnancy. Therefore, this disease cannot be directly prevented. Early detection, early diagnosis, and early treatment are important for preventing this disease. Regular examination should be done during pregnancy. If the child has a tendency to develop abnormalities, chromosome screening should be done in time, and abortion should be performed in time to avoid the birth of the diseased child.
Complication
Congenital pulmonary arteriovenous fistula complications Complications, blood gas, chest, esophagus, chest pain, cerebral thrombosis, brain abscess
Patients with concurrent blood pneumothorax showed chest pain, shortness of breath and shock, and those with central nervous system lesions showed transient cerebral ischemia and cerebral thrombosis, convulsions and even hemiplegia and brain abscess.
Symptom
Congenital pulmonary arteriovenous fistula symptoms Common symptoms Chest pain heart palpitations pulmonary arteriovenous fistula hemoptysis vascular murmur hairpin hypoxemia clubbing (toe) repeated hematemesis
About 10% of patients develop symptoms in infants and young children, and most of them develop symptoms after adulthood, and can also be free of any symptoms. They are found by routine chest X-ray examination. The symptoms depend on the extent and extent of the lesion. The growth is exacerbated, and eventually clinical symptoms appear. The main symptoms are different degrees of hemoptysis, shortness of breath, palpitations and chest pain. Physical examination shows clubbing (toe) and cyanosis. The adjacent chest wall of the lesion can smell vascular murmur. There are extrapulmonary manifestations such as nosebleeds, hematemesis and skin mucosal telangiectasia.
Examine
Congenital pulmonary arteriovenous fistula examination
1. Blood routine examination: erythrocytosis in chronic hypoxia.
2. Arterial blood gas analysis: severe cases showed hypoxemia, arterial partial pressure of oxygen (PaO2) and arterial oxygen saturation (SaO2) decreased, but arterial blood carbon dioxide partial pressure (PaCO2) did not increase, oxygen is difficult to correct low Oxygenemia.
3. Chest X-ray: visible single or multiple coin-like nodular lesions in the lung, ranging from 1cm to several centimeters in diameter, with increased density and uniformity, sharp borders, mostly located in the medial zone of the middle and lower lung fields, and visible drainage shadows Since the hilar door extends to the nodular shadow and is connected, the chest body slice can be more clearly displayed.
4. Chest X-ray: Checked by valsalva method and Mueller method, the shadow of the mass enlarges when deep inhalation, and shrinks when exhaled, and the pulsation of the ipsilateral hilar vasculature increases.
5. Chest computed tomography (CT) scan and magnetic resonance imaging (MRI): lesions that are not found in the chest radiograph can be detected and the nature of the lesion can be further identified.
6. Angiography: It can help to confirm the diagnosis and clear the scope, especially for those who want to undergo surgery.
7. Cardiac catheterization: There may be an increase in cardiac output, but pulmonary artery pressure is normal.
8. ECG examination: mostly in the normal range.
9. Echocardiography: An extracardiac right-left shunt may be found.
Diagnosis
Diagnosis and diagnosis of congenital pulmonary arteriovenous fistula
A preliminary diagnosis can be made based on hypoxemia, pulmonary vascular murmurs, and typical chest X-ray findings.
Can be distinguished from intrapulmonary tuberculosis, benign, malignant tumors, pulmonary parenchymal hemorrhage, pulmonary infarction, monocytoplasmosis or coccidioidomycosis.
