Pulmonary atresia

Introduction Pulmonary Atresia with Intact Ventricular Septum (PAIVS) refers to one or more of the main pulmonary artery, pulmonary valve, and left and right bifurcation of the pulmonary artery, usually accompanied by varying degrees of right ventricle. , tricuspid dysplasia. The ventricular septum is intact and the aorta is normal.

Cause

Most of these congenital malformations involve pulmonary atresia alone and should be distinguished from pulmonary atresia with congenital anomalies. Unlike complex malformations with right aortic and transposition of the aorta (eg, pulmonary atresia with ventricular septal defect, with or without transposition of the aorta), unequal division of the conical trunk is the underlying cause of dysplasia of this type of malformed pulmonary artery. The normal connection between the semilunar valve and the open right ventricular funnel suggests that pulmonary atresia is a primary independent pathological change. Because the embryonic trunk ridges are initially separated from each other, and the three leaflets fuse into a non-porous membranous structure, indicating that this is a secondary change in the later stages of development. Despite the right ventricular outflow tract occlusion, many patients still have three parts of the right ventricle, and the right ventricular cavity is mild to moderately dysplastic. This supports the theory that the pathological changes in the right ventricle are secondary to the severity of tricuspid regurgitation, and that tricuspid regurgitation affects right ventricular filling. Significant tricuspid regurgitation increases the right ventricular volume, resulting in a certain size of the right ventricular cavity. Tricuspid valve function can also be accompanied by right ventricular outflow tract obstruction, which will lead to different degrees of wall bundle hypertrophy, and even the right ventricular trabecular and funnel closure.

The intramyocardial sinus gap described in the literature is a narrow and roundabout gap between the thicker septal bundles, and angiography clearly shows that these voids are consistent with typical sites of the right ventricular trabeculae. Tricuspid and pulmonary valve annulus dysplasia is likely to be the result of the discovery of the dysplasia of the ventricular cavity. During the formation of the cardiac tube, a cystic structure called the mesangial sac is formed on the dorsal side of the cardiac tube. Finally, the structure is located at the two-layer pericardial reflex, and some of the tunica sac are arranged in a longitudinal tunnel. The tunnel is opened in the cardiac lumen along the dorsal side of the cardiac tube. These mesangial sacs form a single layer of vascular wall that eventually develops into a coronary artery system that is connected to the arterial trunk with a cylindrical opening. Therefore, the connection between the coronary system and the right ventricular sinus is the connection between the mesangial sac and the right ventricular trabecular bone during embryonic period. This embryonic connection may explain the presence of coronary artery and right ventricle in some patients. Traffic.

an examination

Diagnosis can be made by signs, chest X-ray, electrocardiogram, cardiac color ultrasound, CT, MRI, right heart catheterization and cardiac angiography. CT and MRI can show the development of pulmonary artery and the establishment of collateral circulation. Right heart catheterization and cardiac angiography are the key to show the disease.

Accurate diagnosis is based on the patient's medical history, clinical manifestations and examinations.

Differential diagnosis

1. The clinical manifestations of ventricular septal defect are similar to those of tetralogy of Fallot, except that cyanosis occurs earlier than quadruple disease, which occurs several days after birth. The systolic murmur is often lighter, and the chest and back may be heard from the artery. Continuous murmur of catheter patency or bronchial collateral circulation. After the first heart sound, the early contraction sound is often heard, and the second heart sound at the bottom of the heart is enhanced and single. X-ray examination showed that the heart shadow increased, the heart and waist were obviously depressed, and the lobes of the bronchus may be seen in the lungs. Echocardiography can confirm the diagnosis.

2. The complete clinical manifestations of ventricular septum are similar to severe pulmonary stenosis, and most of the children die within a few days after birth. If the arterial catheter is continuously open and the hypoxia is mild, the sick child may survive for several weeks, but under normal circumstances, the bruising is significant, the hypoxia is severe, and there is a paroxysmal attack, which is easy to merge with heart failure and enlarge the liver. The jugular vein is only high in waves. Continuous murmurs can often be heard, from patent ductus arteriosus or only mild systolic murmurs, from tricuspid regurgitation, the second heart sound at the bottom of the heart is single, due to the disappearance of the pulmonary valve closure sound, X-ray examination of the heart shadow Mild or extremely increased, the heart and waist are obviously depressed, and the lung field blood vessels are reduced.

The electrocardiogram showed a high P-point and a right ventricular dysplasia, showing left ventricular hypertrophy, but the motor axis was often in the normal range or mild right deviation, which is different from the left axis of the tricuspid atresia. Echocardiography can confirm the diagnosis. Pulmonary atresia, right ventricular cavity size, wall thickness, tricuspid valve morphology and opening and closing function can be displayed, and the size of the foramen ovale or atrial septal defect can be measured. Cardiac catheterization can increase the right atrium and right ventricle. The cardiovascular angiography can confirm that the right ventricle is a blind cavity. The contrast agent is from the right atrium through the atrial septal defect. It enters the left atrium, the left ventricle and the aorta. Enter the passage of the lung circulation.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.