Aorto-pulmonary septal defect
Introduction
Introduction to primary-pulmonary septal defect The main-pulmonary septal defect or the main-pulmonary window is a rare congenital major vascular malformation. According to Stansel in 1977, there are fewer than 100 cases of surgical procedures reported in the literature. The defect or window is located in the ascending aorta. The pathophysiology and clinical manifestations between the common pulmonary arteries resemble patent ductus arteriosus. At the 5th to 8th week of the embryonic period, the main-pulmonary artery divides the arterial trunk into the ascending aorta and the common pulmonary artery. During the same period, the interventricular septum divides the ventricular cavity into the left and right ventricles. The lower part of the final arterial septum merges with the upper part of the interventricular septum, allowing the left and right ventricles to communicate with the aorta and pulmonary artery, respectively. If the above separation is not perfect, according to its position, the main-pulmonary artery septal defect, persistent arterial trunk or high ventricular septal defect are formed. basic knowledge The proportion of sickness: 0.01% Susceptible people: no special people Mode of infection: non-infectious Complications: congestive heart failure, pulmonary hypertension, septal defect
Cause
Main-pulmonary artery septal defect
Pathogenesis
The main-pulmonary septal defect leads to a cyclical physiological abnormality. In the early stage, due to the large amount of blood flow, the autonomic artery was shunted to the pulmonary artery, and the blood volume of the pulmonary venous return to the left heart chamber increased, which aggravated the left ventricular burden, thus causing left ventricular hypertrophy and strain, while the systemic blood flow was relatively insufficient, resulting in dysplasia or retardation. . Due to congestion of the lungs, it is easy to cause respiratory infections. In the later stage, secondary lesions such as thickening of the wall and small lumen of the pulmonary arterioles increased pulmonary resistance, increased pressure, and excessive load on the right ventricle, causing hypertrophy of the left and right ventricles. When the pulmonary artery pressure is higher than the aorta, a reverse (right to left) shunt is formed, and systemic purpura appears.
Pathological change
A typical primary-pulmonary septal defect is anatomically located just above the aortic valve, forming an aortic root that communicates with the common pulmonary artery. Defective diameters can range from a few millimeters to a few centimeters, typically above 1 cm. Some patients have larger diameters and the lower edge is very close to the aortic valve, which is difficult to distinguish from the persistent arterial trunk.
Prevention
Primary-pulmonary septal defect prevention
The disease is congenital macrovascular malformation, so there is no effective preventive measures at present, early detection and early treatment should be found early.
Complication
Main-pulmonary septal defect complications Complications, congestive heart failure, pulmonary hypertension, atrial septal defect
Many patients die of congestive heart failure in infants or early childhood. Survivors are prone to respiratory tract infections and dysplasia. When the advanced pulmonary hypertension is severely reversed, systemic purpura occurs. This disease is often combined with other diseases. Congenital heart malformations, such as atrial septal defect.
Symptom
Symptoms of main-pulmonary septal defect common symptoms purpura, irritability, tremor, ventricular hypertrophy, capillary pulsation
The clinical manifestations mainly depend on the amount of blood flow from the aorta to the pulmonary artery, and whether secondary pulmonary hypertension and its degree occur. Because the defect is generally larger than the diameter of the aortic catheter and the location of the shunt is close to the heart, many patients In infants or early childhood, they die of congestive heart failure. Survivors are palpitations, shortness of breath, fatigue, and are prone to respiratory infections and dysplasia. They are generally more prominent than patent ductus arteriosus. When advanced pulmonary hypertension is severely reversed, Systemic purpura (rather than lower abdominal purpura in patients with patent ductus arteriosus), endocarditis has been rare since the widespread use of antibiotics.
Examine
Primary-pulmonary septal defect examination
At the time of physical examination, continuous machine-like murmurs can be heard between the 3rd and 4th ribs on the left sternal border. If there is obvious pulmonary hypertension, only systolic murmurs can be heard. The murmur is generally louder than the patent ductus arteriosus and is superficial. The same site can be tremor and tremor, the second sound of the pulmonary artery is hyperthyroidism, or accompanied by a murmur of the pulmonary insufficiency (Graham Steell murmur). When the flow rate is large, the diastolic murmur caused by the relative stenosis of the tricuspid valve can often be heard at the apex of the apex. Due to the widening of the pulse pressure, signs such as water impulses, femoral artery gunshots, and capillary pulsations are more pronounced than those of patent ductus arteriosus.
Electrocardiogram examination showed hypertrophy of the left ventricle or hypertrophy of the left and right ventricles.
Chest X-ray examination showed a marked enlargement of the heart, prominent pulmonary artery segments, and enlarged ascending aorta.
Ultrasound imaging showed an abnormal passage between the ascending aorta and the pulmonary artery.
Diagnosis
Diagnosis and diagnosis of main-pulmonary septal defect
The disease needs to be closed with patent ductus arteriosus, permanent arterial trunk, aortic sinus tumor broken into the right heart chamber, and the right side of the coronary artery is differentiated.
1, patent ductus arteriosus
Patent ductus arteriosus refers to a vessel that communicates between the left pulmonary artery root and the descending aortic isthmus that communicates between the pulmonary artery and the descending aorta without closure after birth.
The symptoms of patent ductus arteriosus depend on the thickness of the catheter, the size of the flow, the level of pulmonary vascular resistance, the age of the patient, and the combined intracardiac malformation. Although the catheter is thick in full-term infants, it needs 6-8 weeks after birth. Symptoms appear after the vascular resistance is reduced. In premature infants, because the pulmonary arterioles have less smooth muscle and vascular resistance declines earlier, symptoms can occur in the first week, often with shortness of breath, tachycardia and acute dyspnea. It is more obvious, and is prone to colds and upper respiratory tract infections, pneumonia, etc. After that, it is compensated in childhood, and there are few self-conscious symptoms. It is only poorly developed and thin. Some children are tired and guilty only after exertion. Patients with moderately sized catheters are generally asymptomatic. It is not until after severe activity in their 20s that there is an air urgency, palpitations and other symptoms of decompensation. Although pulmonary hypertension can occur below 2 years of age, the obvious signs of pulmonary hypertension are mostly in age. Larger to show dizziness, shortness of breath, hemoptysis, cyanosis after activity (more than half of the body is obvious), if accompanied by subacute endocarditis, there is fever , systemic symptoms such as loss of appetite, sweating, endocarditis rarely occurs in childhood, but more common in adolescence.
In patients with large patent ductus arteriosus, the left thoracic abdomen is slightly elevated, and the apex beats are enhanced. Generally, the second and third intercostal ridges and localized tremor can be seen on the left sternal border, and a loud continuous machine-like sample III can be heard. Cardiac murmur above grade IV, mainly to the left lateral thoracic, left subclavian or left neck, the loudness of the diastolic component decreases with the increase of pulmonary artery pressure, and only systolic murmur is left in severe pulmonary hypertension, accompanied by tremor See also weakened or even disappeared. In addition, in the apical area, the soft diastolic grade II heart murmur produced by functional mitral stenosis can be heard in the apical region. The second heart sound in the pulmonary valve area of pulmonary hypertension is often Machine-like noise can't be covered, and pulmonary hypertension can cause pulmonary stenosis to cause dysfunction. Graham S. reell Murmur can still hear pulmonary regurgitation above the left sternal border.
Blood pressure can be normal, but when the flow rate is large, the systolic blood pressure tends to increase, and the diastolic blood pressure drops, even to zero point. Therefore, peripheral vascular signs appear, such as increased pulse pressure, large pulse, enhanced carotid pulsation, and water pulse. Capillary pulsation in the nail bed or skin; and the sound of gunshots can be heard, and these vascular signs are alleviated and disappear with the increase of pulmonary artery pressure.
2, permanent arterial trunk type I
Perpetual arterial trunk refers to the left and right ventricles all emitting blood to a common arterial trunk. The semilunar valve of the arterial trunk rides over the high ventricular septal defect. The anatomy only sees the total trunk, and there is no occluded main, the remains of the pulmonary artery. The systemic circulation, pulmonary circulation and coronary circulation blood supply are directly from the arteries. The permanent arterial trunk type I refers to the partial division of the arterial trunk. The pulmonary trunk originates from the proximal end of the arterial trunk, and the left and right ascending aorta are in the same plane. The blood of both sides of the ventricle is common, accounting for about 48%. The baby has high pulmonary vascular bed resistance, few pulmonary blood flow, and the clinical symptoms are not obvious within a few weeks after birth. Symptoms of heart failure and pulmonary infection may occur. People with increased pulmonary blood flow often have difficulty breathing, heart failure and tachycardia, and decreased blood flow in the lungs, accompanied by erythrocytosis and clubbing (toe).
