congenital aortic arch malformation
Introduction
Introduction to congenital aortic arch malformation Congenital aortic arch malformation refers to abnormal development of the aortic arch and its branches, resulting in compression of the trachea and / or esophagus. Hommel described the double aortic arch in 1737. In 1939, Wolman described the clinical manifestations of the bi-aortic arch compression of the trachea and esophagus. Gross performed surgical treatment of the first double aortic arch in 1945, which promoted the discovery and understanding of various types of aortic arch deformities. Diagnostic techniques and treatment methods were also developed and improved, and the curative effect was good. In congenital heart vascular malformations, the aortic arch and its branch deformities account for only 1-2%. basic knowledge The proportion of diseases: congenital diseases, the incidence rate in neonates is about 0.01% - 0.03% Susceptible people: no special people Mode of infection: non-infectious Complications: arrhythmia pulmonary hypertension chronic cardiac insufficiency
Cause
Causes of congenital aortic arch deformity
At the 4th week of embryonic development, the front end of the dorsal aorta bypasses the pharynx and forms the first pair of aortic arch and the left and right primordial aorta on the ventral side of the foregut. The latter fuse with each other to form the aortic sac. The growth of the zygomatic arch has six pairs of radial arches from the aortic sac and is connected with the dorsal aorta. When the third pair of iliac arteries are fully developed, the first and second pairs of radial artery arches disappear, and the third pair The common arterial arch forms the common carotid artery and a part of the internal carotid artery. The fourth pair forms the aortic arch on the left side of the radial artery. The right side forms the innominate artery and the right subclavian artery. The fifth pair of radial artery arch does not exist constantly or disappears immediately. The pulmonary artery is formed in the radial artery, and the distal segment of the right side is disconnected from the dorsal aorta; the left side is persistently called the arterial catheter during the fetal period, and the catheter is closed to become the arterial catheter ligament after birth.
Normal aortic arch embryology
Abnormalities occur during the development of the radial artery or dorsal aorta, and various aortic arches and their branch deformities can be formed after birth. In most cases, only the aortic arch or its branches are deformed, and in a few cases, other cardiac malformations such as Falun IV can be used. Joint disease, aortic dislocation, etc., according to the development of the fourth iliac artery arch and aortic arch branch, the location of the descending aorta and the stroke of the arterial catheter or arterial ligament, can divide the aortic arch and its branch abnormalities into the following types.
Double aortic arch: Both sides of the 4th iliac artery arch survive and grow to form an aortic arch. The ascending aorta is normal. It is divided into left and right aortic arches outside the pericardium. The left aortic arch walks from right to left in front of the trachea. The left main bronchus merges with the right aortic arch to synthesize the descending aorta on the left side of the spine. The right aortic arch spans the right main bronchus in front of the spine, behind the esophagus, across the midline to the left, and the left aortic arch merges to form the descending aorta. The left and right aortic arches each have two branches, that is, the left aortic arch sends out the left common carotid artery and the left subclavian artery, the right aortic arch sends out the right common carotid artery and the right subclavian artery, and the arterial catheter or arterial ligament is located in the left aortic arch. The lower edge of the left subclavian artery starting point and the left pulmonary artery, in most cases, the aortic arch diameter is not equal, generally the right side is thicker.
(1) positive view; (2) side view.
Double aortic arch
In a small number of cases, the descending aorta is located on the right side, the left arterial arch spans the left main bronchus, and the posterior rightward of the esophagus, and the right aortic arch is merged into the descending aorta at the right side of the spine, regardless of whether the descending aorta is located on the left or right side. Because the vascular ring formed by the bilateral aortic arch surrounds the trachea, the esophagus, such as the narrow space between the two arterial arches, can clinically produce compression symptoms.
Sometimes the left aorta may be occluded in the distal segment, resembling a cellulose band. The occlusion site may be located between the left common carotid artery and the left subclavian artery. It may also be located between the left subclavian artery and the arterial catheter or arterial ligament or the arterial catheter (arterial ligament). ) between the confluence of the left and right aortic arches.
6 double aortic arch left arch occlusion
Right aortic arch: the left axillary arch disappeared, the right aortic arch developed, the descending aorta was located on the right side of the spine, and the order from the aortic arch was normal, ie the first branch was the left unnamed artery. Re-issue the left common carotid artery and the left subclavian artery; the second branch is the right common carotid artery; the third branch is the right subclavian artery, sometimes the aortic arch sends out 4 branches, while the left innominate artery does not exist, the arterial catheter or arterial ligament Located in the left innominate artery or between the left subclavian artery and the left pulmonary artery, the avascular tube behind the esophagus does not constitute a vascular ring, the right aortic arch generally does not compress the trachea and esophagus, but there are a few cases of arterial catheter or arterial ligament, from the left pulmonary artery The left esophagus is connected to the distal part of the right aortic arch, or the left subclavian artery originates from the proximal descending aorta. The posterior esophagus enters the left upper limb. The arterial catheter or arterial ligament can also be located in the left left pulmonary artery and the left subclavian artery. Between, or between the left pulmonary artery and the left subclavian artery originating from the descending aorta, in these cases, such as an arterial catheter Arterial shorter ligament may be involved in a ring form part of a blood vessel, resulting in trachea, esophagus compression symptoms.
(1) right aortic arch; (2) right aortic arch left subclavian artery caused compression.
Right aortic arch
Left aortic arch: the left aortic arch rarely forms a vascular ring. In some cases, the left subclavian artery ectopic originates from the aortic arch distal to the left subclavian artery, and passes over the esophagus to the right upper extremity. Sometimes the arterial catheter or arterial ligament is ectopically connected. Between the right subclavian artery and the right pulmonary artery; and the left aortic arch with the right descending aorta, the left aortic arch is connected to the descending aorta around the esophagus, and the right arterial catheter or arterial ligament is involved in the formation of the vascular ring, or The ectopic left subclavian artery originates from the proximal part of the descending aorta and enters the left upper limb through the esophagus. These conditions can form a vascular ring and produce compression symptoms.
Left aortic arch ectopic right sublingual artery compression esophagus
Anonymous artery abnormality: the aortic arch and its branches develop normally, but the part of the innominate artery from the aortic arch is biased to the left side, and the right anterior wall of the trachea is turned up and to the right to the top of the right chest. If the innominate artery is long and loose, no symptoms are produced, but the blood vessels are thick. Short and tight, it can severely compress the trachea.
Ectopic vagus left pulmonary artery: Glaevecke and Doehle first reported in 1897 that the ectopic vagus left pulmonary artery originated from the posterior pulmonary artery, then crossed the right main bronchus to the left, and entered the left hilar between the trachea and the esophagus, thus forming a wrapped right The main bronchus and the sling of the lower trachea produce compression symptoms, which may be associated with dysplasia of the lower trachea and right main bronchus. Half of the patients present symptoms after birth, and about 2/3 of the cases appear symptoms 1 month after birth, the most common Symptoms are respiratory obstruction, wheezing during exhalation, often recurrent acute respiratory obstruction and respiratory infection, but does not present symptoms of dysphagia.
Chest X-ray examination can be found on both sides of the lungs with different transmittance, the right lung is over-inflated, the chest flat film in the bulge area between the trachea, esophagus, can show abnormal left pulmonary artery block shadow, left pulmonary artery in the left hilar Biliary bronchoscopy or bronchography can show coexisting tracheobronchial abnormalities, but these tests can cause aggravation of respiratory infarction. Chest X-ray examination can detect differences in tracheal width on both sides, and sometimes pulmonary angiography can confirm the diagnosis.
Prevention
Congenital aortic arch deformity prevention
The disease is a congenital disease, so there is no effective preventive measures. At present, the operative mortality rate has dropped to 5-10%, and there are no other cases of congenital cardiovascular malformation, and the long-term curative effect is good.
Complication
Congenital aortic arch malformation complications Complications arrhythmia pulmonary hypertension chronic cardiac insufficiency
1, cardiac insufficiency
Cardiac systolic function is abnormal, so that when the circulating blood volume and vasomotor function are normal, the blood pumped by the heart can not meet the needs of the tissue, or can only meet the metabolic needs when the ventricular filling pressure is increased; at this time, the neurohumoral factor is Activation of participation compensation, the formation of a clinical syndrome with hemodynamic function director and neurohumoral activation features, for patients, cardiac dysfunction is a heavy topic, because it is a syndrome, fatigue, shortness of breath, palpitations, Weight loss, muscle relaxation and atrophy, bed rest throughout the day, is a common clinical syndrome, its incidence is high, mortality is also high, the main causes of chronic heart failure are various chronic myocardial lesions and long-term ventricular overload.
2, arrhythmia
Refers to any abnormality in the origin of heart rhythm, heart rate and rhythm, and impulse conduction. The ECG record at the onset of arrhythmia is an important basis for the diagnosis of arrhythmia. It should include a longer II or V1 lead record, pay attention to P and QRS. Wave morphology, P-QRS relationship, PP, PR and RR interval, determine whether the basic heart rhythm is sinus or ectopic, and find the origin of P wave and QRS complex when the chamber is independent (Selection II, aVF, aVR, V1 and V5, V6 lead), when the P wave is not obvious, try to increase the voltage or speed up the paper speed, make a long record of the obvious lead of the P wave, if necessary, you can also use the esophageal lead or the right atrial electrical The figure shows the P wave. When the above method is used to consciously search for QRS, ST and T waves but there is still no P wave, consider atrial fibrillation, fluttering, atrioventricular junction rhythm or atrial pause, etc., by analyzing one by one. Or delay the nature and source of the heartbeat, and finally judge the nature of the arrhythmia.
3, pulmonary hypertension crisis
Pulmonary hypertension after cardiac surgery is a serious pathological condition caused by a vicious circle of hypoxia-pulmonary contraction-pulmonary hypertension, which can threaten the lives of patients at any time.
Symptom
Congenital aortic arch deformity symptoms Common symptoms Dyspnea traumatic purpura dysphagia Dyspnea refusal to eat stagnation hardening persistent cough breath sound rough
Chest X-ray examination: no other cases of congenital heart malformation, chest radiographs can be abnormal, the double aortic arch case can show bilateral aortic arch bulge, the right side is more obvious, esophagoscopy can be displayed in the thoracic vertebra In the upper third and fourth levels of the esophagus on both sides of the esophagus, the right aortic arch caused by a larger impression and higher position, the left aortic arch caused by lesser and lower position, the body layer may show signs of compression of the tracheal cavity In the right aortic arch, the chest X-ray showed only the aortic arch bulge on the right side, but the left side was absent. The esophagic angiography was performed at the aortic arch site. The esophagus was pushed to the left and showed the impression. The ectopic subclavian artery case Esophageal angiography can show that the posterior wall of the esophagus is subjected to oblique or spiral compression by vascular compression. In infants, esophageal angiography should be performed with iodized oil or water-soluble contrast agent, because the contrast agent such as inhalation tracheobronchial is aggravated. Difficulty breathing or risk of aspiration pneumonia.
Bronchoscopy: Bronchoscopy can identify the site of compression of the trachea, and can observe pulsation of the blood vessels under pressure, but the respiratory mucosal trauma and edema can increase the obstruction of the respiratory tract, which must be very careful.
Aortic angiography: Aortic angiography is the most reliable diagnostic method for the diagnosis of aortic arch and its branch malformation. A catheter is inserted into the ascending aorta, contrast agent is injected for aorta and its branch angiography, and a two-way film examination can show the aortic arch and its The origin, direction, thickness and other anomalies of the branch are used to confirm the diagnosis.
Aortic arch and its branch malformation itself have no effect on circulatory physiology and hemodynamics, but if the vascular ring or vascular ring together with fibrin or ectopic aortic arch branches against the trachea and esophagus, it can be clinically significant. If the respiratory tract is stressed and/or dysphagia, severe cases can lead to death.
Trachea, severe esophageal compression, after birth can show inspiratory wheezing with expiratory wheezing and shortness of breath, rough breath, persistent cough, crying hoarseness, sometimes breathing difficulties, cyanosis, short Respiratory pause or loss of consciousness, when eating and lying on the back, the symptoms of dyspnea are aggravated. When lying on the side and head and neck, the symptoms can be alleviated. If the respiratory tract is severe, the upper clavicle and the lower edge of the rib can be retracted. Repeated episodes of respiratory infections, increased symptoms of respiratory obstruction at the time of onset, cases of esophageal compression, often refused to eat and presented dysphagia, often with seizures when eating, accompanied by vomiting, increased difficulty in breathing and other symptoms, nutritional dysplasia.
In most cases, the above-mentioned trachea and esophageal compression symptoms begin to appear within 6 months after birth. Symptoms of severe compression can present symptoms within a few days after birth. These diseases, for example, are untreated and often die before the first birthday of birth. In milder cases, the symptoms that appear only 6 months after birth and do not continue to worsen may gradually disappear during the growth phase, but when the respiratory infection is complicated, the symptoms are aggravated, due to the ectopic origin of the subclavian artery compression. Symptoms of dysphagia caused by esophagus may appear after middle-aged (40 years old), ectopic arteriosclerotic lesions enlarge and thicken, and symptoms may appear. Sometimes ectopic subclavian artery may develop aneurysm-like enlargement.
Examine
Examination of congenital aortic arch deformity
Chest X-ray examination: no other cases of congenital heart malformation, chest radiographs can be abnormal, the double aortic arch case can show bilateral aortic arch bulge, the right side is more obvious, esophagoscopy can be displayed in the thoracic vertebra In the upper third and fourth levels of the esophagus on both sides of the esophagus, the right aortic arch caused by a larger impression and higher position, the left aortic arch caused by lesser and lower position, the body layer may show signs of compression of the tracheal cavity In the right aortic arch, the chest X-ray showed only the aortic arch bulge on the right side, but the left side was absent. The esophagic angiography was performed at the aortic arch site. The esophagus was pushed to the left and showed the impression. The ectopic subclavian artery case Esophageal angiography can show that the posterior wall of the esophagus is subjected to oblique or spiral compression by vascular compression. In infants, esophageal angiography should be performed with iodized oil or water-soluble contrast agent, because the contrast agent such as inhalation tracheobronchial is aggravated. Difficulty breathing or risk of aspiration pneumonia.
Bronchoscopy: Bronchoscopy can identify the site of compression of the trachea, and can observe pulsation of the blood vessels under pressure, but the respiratory mucosal trauma and edema can increase the obstruction of the respiratory tract, which must be very careful.
Aortic angiography: Aortic angiography is the most reliable diagnostic method for the diagnosis of aortic arch and its branch malformation. A catheter is inserted into the ascending aorta, contrast agent is injected for aorta and its branch angiography, and a two-way film examination can show the aortic arch and its The origin, direction, thickness and other anomalies of the branch are used to confirm the diagnosis.
Diagnosis
Diagnosis and diagnosis of congenital aortic arch deformity
For the diagnosis of this disease, various types of congenital aortic arch malformations should be identified clinically, including obstructive congenital aortic arch deformities such as aortic coarctation and aortic arch interruption, non-obstructive congenital aortic arch deformities such as double aortic arch and right aortic arch With the vagus left subclavian artery, etc., it may also include shunt congenital aortic arch deformity such as patent ductus arteriosus.
1, aortic coarctation
The main lesion is aortic limited stenosis or occlusion caused by aortic blood flow disorder. The majority of the lesions in the aortic constriction (more than 95%) are at the junction of the distal aortic arch and the descending aorta. That is, the aortic isthmus, adjacent to the arterial catheter or the ligament region of the artery, but in a few cases, the narrowing segment can be located in the aortic arch, the descending thoracic aorta or even the abdominal aorta. Sometimes the aorta can be narrowed in two places, and very few patients have a family. History, the disease is more common in men, the ratio of male to female is 3 to 5:1, the clinical manifestations of aortic coarctation, with the narrowing of the lesion, the degree of narrowing, whether there are other cardiovascular vascular malformations and different age groups .
2, aortic arch interruption
Aortic arch interruption (AII) refers to luminal atresia or a part of the aortic arch. The anatomical aortic arch is dissected, and the distal lumen is discontinuous, resulting in a cross between the two parts of the aortic arch or the aortic arch. The blood flow between the descending aorta is interrupted, and the aortic arch interruption is almost always combined with the coarse PDA and VSD. It can also be combined with other abnormalities of the intracardiac malformation and the connection between the large blood vessels and the ventricle. The PDA is the aortic arch interrupted to survive after birth. The condition of the interruption of the distal aortic arch and the descending aorta is from the right atrium or / and the right ventricle through ASD or VSD, provided by PDA, the child's postoperative pressure gradient due to decreased pulmonary circulation, left and right ventricles Increase, left-to-right shunt through VSD, leading to congestive heart failure, if combined with PDA small or left ventricular outflow tract obstruction, can lead to refractory heart failure, most cases die in the neonatal period, a small number of survivors appear Secondary pulmonary tuberculosis leads to pulmonary hypertension and progressive to heart failure.
3, double aortic arch
Both sides of the 4th iliac artery arches survive and grow to form the aortic arch, the ascending aorta is normal, divided into left and right aortic arches outside the pericardium, and the left aortic arch walks from right to left in front of the trachea, crossing the left main bronchus On the left side of the spine and the right aortic arch merge to form the descending aorta, the right aortic arch spans the right main bronchus in front of the spine, behind the esophagus, across the midline to the left, and the left aortic arch merges into the descending aorta, left and right The aortic arches are divided into two branches, that is, the left aortic arch sends out the left common carotid artery and the left subclavian artery, the right aortic arch sends out the right common carotid artery and the right subclavian artery, and the arterial catheter or arterial ligament is located in the left aortic arch, under the left subclavian bone. Between the lower edge of the arterial starting point and the left pulmonary artery, the aortic arch diameter is not equal on most sides of the case, generally the right side is thicker. In a few cases, the descending aorta is located on the right side, the left arterial arch crosses the left main bronchus, and backwards to the right. Behind the esophagus, the right aortic arch and the right aorta arch merge into a descending aorta, regardless of whether the descending aorta is located to the left or right. On the side, because the vascular ring formed by the bilateral aortic arch surrounds the trachea, the esophagus, such as the narrow space between the two arterial arches, can clinically produce compression symptoms.
4, right aortic arch with vagus left subclavian artery
Right aortic arch and left vagus subclavian artery This is the most common type of right aortic arch deformity. This abnormality rarely causes symptoms and complicated other cardiac malformations. Therefore, adults with right aortic arch are almost all of this type, but in Older patients may have esophageal or tracheal compression symptoms due to hardening and distortion of large blood vessels. The development process is the interruption of the left arch of this embryo between the left subclavian artery and the left common carotid artery, and the distal end of the left arch of the embryo. Partially developed into an arterial diverticulum, when the vagus left subclavian artery originated at this time, often produces a large occupying effect behind the esophagus, the descending aorta can descend to the left or right side of the spine, and on the right side Common, when the esophageal indentation is not obvious, esophageal angiography only shows a small transverse line of the posterior esophagus, which is caused by the vagus left subclavian artery across the spine. In a few cases, the posterior segment of the right aortic arch crosses the esophagus. When the midline falls to the left side of the spine, the chest radiograph is misinterpreted as a double aortic arch. Esophageal angiography shows the esophageal advancement. CT scan is mainly used to exclude the mediastinal mass. To further understand the type of blood vessels, CT showed that the position of the right aortic arch was usually higher, mostly at the level of the left forearm vein, and it was closer to the sagittal direction than the oblique direction. There were four branches on the arch, from the proximal end of the aortic arch. The order of the distal to the left common carotid artery, the right common carotid artery, the right subclavian artery and the left subclavian artery, the left subclavian artery is usually larger, from the back of the esophagus to the left side of the trachea to the left side of the trachea.
5, patent ductus arteriosus
Patent ductus arteriosusi (pda) is one of the most common congenital heart diseases in children. The arterial catheter is the main physiological blood flow channel in the fetal blood circulation. It is normally closed after birth, and then dissected. Closed, but under the influence of certain pathological conditions, the arterial catheter remains open, which means that the patent ductus arteriosus is closed. Because the aortic pressure is higher than the pulmonary artery pressure, blood is blocked from the aorta through the patent in the systolic or diastolic phase. The catheter is shunted to the pulmonary artery, which causes the left ventricular volume overload and pulmonary blood flow to increase significantly, resulting in pulmonary hypertension and right ventricular overload. Pulmonary hypertension begins to develop from dynamic to resistive, and finally right to left shunt. The catheter is small, the flow rate is small, there is no self-consciousness, the middle of the catheter has difficulty breathing during exercise, it is easy to get tired on weekdays, recurrent respiratory infection or heart failure, or complicated with bacterial endocarditis, there is a symptom of systemic infection. Such as fever, chest pain and peripheral blood vessel embolism symptoms.
