Atrioventricular septal defect repair surgery

Atrioventricular septal defect is a group of congenital heart malformations with extremely morphological changes. It is characterized by the absence or absence of interstitial tissue at or below the atrioventricular valve plane, and the atrioventricular valve has different degrees of malformation. Atrioventricular septal defect, also known as endometrial pad defect and atrioventricular tube malformation, is a relatively common congenital heart disease, with 1.9 cases per 10,000 live births and 4% to 5% in congenital heart disease. In 12044 cases of congenital heart disease in the General Hospital of Shenyang Military Region, 280 cases of atrioventricular septal defect, accounting for 2.3%. In 1936, Abbott recognized the primary ventricular septal defect and common atrioventricular tube malformation. In 1956 and 1958, Wakai and Edward named the above-mentioned malformations as partial and complete atrioventricular tube malformations and added intermediate types. In 1958, Lev described the location of the abnormal atrioventricular node and conduction beam. In 1966, Rastelli divided the complete atrioventricular septal defect into three types: A, B, and C. In 1954, Kirklin applied atrial wells to partially repair some of the atrioventricular septal defects. In 1955, Lillehei reported for the first time that partial and complete atrioventricular septal defects were performed under the cross-circulation. In 1977, Mair and McGoon and others demonstrated that complete atrial septal defect can be performed in infants within 1 year of age, and then the surgery is improved 6 months after birth or 2 to 3 months after birth. In 1962, Maloney and 1976 Trusler reported the use of one and two patches to repair complete atrioventricular septal defect, and advocated suturing the mitral valve fissure, which became the current routine surgical procedure for this deformity. In China, in 1964, Xue Yuxing reported repairing partial atrial septal defect under cardiopulmonary bypass. In 1980, Pan Zhi used two patches to repair complete atrioventricular septal defect, which was successful and was promoted nationwide. Treatment of diseases: atrial septal defect Indication 1. In some cases of partial atrial septal defect with mild or no mitral regurgitation, the elective operation time is 1 to 2 years old. At this time, the surgical valve function is good; if the operation is delayed, the mitral valve fissure thickening and the leaflet deformation and curling may affect its effect. Once mitral regurgitation is aggravated, intracardiac repair should be performed in time. 10% to 20% of patients with congestive heart failure or a common atrium during infancy should be operated within 6 months of life, which can avoid pulmonary vascular disease. If the left lower lobe tissue is absent or a single papillary muscle on the left side, medical treatment should be performed first. In children, a larger type of bilobal mechanical valve is used for mitral valve replacement. Adults over 40 years of age with atrial fibrillation and/or heart failure should undergo intracardiac repair plus right maze surgery to achieve satisfactory results. 2. Patients with complete atrioventricular septal defect have congestive heart failure during infancy and should be operated within 2 to 3 months after birth. In general, if obstructive pulmonary vascular disease can occur at the age of 1 year or earlier, surgery should be performed within 6 months after birth. The advantages of early surgery within 3 to 6 months after birth are: 1 to protect the atrioventricular valve function, to prevent thickening, curling and deformation of the leaflets; 2 to avoid obstructive pulmonary vascular disease after 1 year; 3 to promote growth and development; 4 The surgical mortality rate within 6 months after birth is lower than 7 to 12 months after birth. Congenital stupidity is not a contraindication for surgery. Obstructive pulmonary vascular disease occurs earlier and should be operated within 3 to 6 months after birth. Pulmonary artery atrophy is currently rarely used. 3. Complete atrioventricular septal defect with left ventricular (or) right ventricular dysplasia, bidirectional cavopulmonary bypass should be applied 4 to 6 months after birth, and total vena cava and pulmonary artery connection should be performed at 2 to 4 years old. Contraindications 1. Patients with severe pulmonary hypertension, cyanosis at rest, pulmonary vascular resistance >10U/m2 or lung/systemic vascular resistance ratio >0.75 is a contraindication for intracardiac repair of atrioventricular septal defect. 2. Atrioventricular septal defect combined with other complicated cardiac malformations that cannot be repaired or severe liver and kidney dysfunction. Preoperative preparation 1. Patients with congestive heart failure should first use medical treatment such as digitalis and diuretics to improve cardiac function. If the treatment is ineffective in a short period of time, early surgery should be performed. 2. For patients with complete atrioventricular septal defect and severe pulmonary hypertension, oxygen therapy is used, and pulmonary vascular drugs such as sodium nitroprusside, prostaglandin E1 or carbon monoxide are used to reduce pulmonary vascular resistance. If the patient passes the cardiac catheterization and the pulmonary vascular resistance is between 8 and 10 U/m2, he should be actively prepared for early surgery. 3. Prevent respiratory infections. If the patient has cough, cough and dry and wet voice in the lungs, appropriate antibiotics should be used to prevent respiratory infections on the basis of controlling heart failure. 4. For patients with bacterial endocarditis, routine antibiotics should be used for 1 to 3 months of systemic treatment, until the condition is stable after surgery; but in difficult cases, use strong antibiotics for 5 to 7 days, in infection activities Surgical treatment. 5. Comprehensive analysis of clinical, echocardiography and cardiovascular angiography to further verify the diagnosis and surgical indications. In particular, it is necessary to check whether the left atrioventricular valve double valve, the left ventricle single papillary muscle, the left atrioventricular valve deficiency, and ventricular dysplasia and subaortic stenosis are severe deformities, so as to develop a surgical plan and plan to reduce the surgical mortality. And complications. 6. Planned Fontan surgery, preoperative preparation of bidirectional cavopulmonary bypass and total vena cava connection to the pulmonary artery. Surgical procedure The median incision in the chest, free thymus and most of the resection, biased the right atrium to cut the happy bag, retain a large pericardium to prepare for the repair of the primary hole atrial septal defect. An aortic perfusion tube was inserted under the innominate artery and inserted directly into the right angle tube of the superior and inferior vena cava. After extracorporeal circulation cooling and cardiac arrest, the following various operations were performed. 1. Partial ventricular septal defect repair Through the right atrial incision in the parallel interventricular sulcus, intracardiac exploration of the presence or absence of malformations such as no coronary sinus, pulmonary stenosis and secondary atrial septal defect. The mitral valve must be tested for closure. Only a few cases were not closed, but most of them had reflux at the center of the mitral valve 3 or at the 1 and 2 sides. The left upper valve leaflet and the left lower valve flap were thickened and 3~4 needles were sutured intermittently. Repeated water injection test confirmed that the mitral valve was completely closed. If there is still reflux in the center of the valve, the suture should be sutured at the tip of the left upper left and lower left lobe. If there is reflux on the 1st or 2nd side, the mitral lateral annulus will be partially folded at the corresponding site. After the mitral valve was found to have no stenosis and regurgitation, a large pericardium was used to repair the atrial septal defect. Sew in the danger zone to the root of the right lower lobe of the tricuspid valve. Apply 5 to 6 sutures of the 4-0 polyester tape with the suture to the right leaflet of the adjacent branch, and pass the needle from the ventricular surface through the root of the valve. The needle is placed on the atrial surface and pushed through the pericardium. The 4-0 polypropylene thread was sutured continuously around the outer side of the coronary sinus ostium, the edge of the primary atrial septal defect to the upper edge of the anterior septum, and the defect was closed. The right upper lobe of the tricuspid valve is fixed on the pericardial piece, and the right lower inferior leaflet is made into a 2-needle intermittent type, so that the tricuspid valve is completely closed. Finally suture the right atrial incision. Primary atrial septal defect and common atrium are similar to the above procedure. The origin of the primary atrial septal defect has a normal second and tricuspid valve structure. The root of the lower half of the diaphragm is sewed in the dangerous area, and the outer side of the coronary sinus ostium is also wound. The defect is closed with a pericardium. There are 6 leaflets in the common atrium. The mitral regurgitation must be repaired first, and then the larger pericardium is used to close the atrial septal defect. Simultaneous repair of combined malformations during surgery, such as anterior ligation of patent ductus arteriosus before bypass, intraoperative suture of secondary atrial septal defect, the left superior vena cava into the left atrium (also known as complete nodular coronary sinus syndrome) The tunnel or patch allows the vein to be drained to the right atrium, etc., as well as a pulmonary valve incision and a three-atrial septal resection. 10.2 2. Complete atrioventricular septal defect repair A method of repairing the primary atrial septal defect and ventricular septal defect with two patches through the right atrial incision in the parallel atrioventricular groove. Observe the deformed structure and design a surgical plan. In the water injection test, a 1-needle polyester thread was made at the best joint point of the anterior and posterior bridges, and the line was pulled to the left side to show the chordae and/or papillary muscles at the interventricular septum, and the ventricular septal defect was measured. Length and height, cut into semi-circular patches. The right ventricular surface and the tricuspid valve of the ventricular septal defect edge were attached to the root of the right lower lobes of the annulus with a sacral suture with a shimming, and the ligation was performed. The left and lower left lobes of the mitral valve were raised 1.5 to 2.0 cm to the straight edge of the ventricular septal defect patch, and the pericardium was sandwiched with a discontinuous or continuous wall suture with a gasket to fix it. At this point, the water injection test must be repeated to observe whether the mitral valve is closed or not. Intermittent sutures of the leaflet fissures of the upper left and lower left leaflets are required. Later, the pericardium should be used to repair the primary atrial septal defect. The above procedure is applicable to the Type C of the Rastelli classification. In the case of type C complete atrioventricular septal defect, if it is 4 leaflets, it needs to be biased to the right side, and the anterior and posterior anterior and posterior anterior and posterior anterior and posterior anterior and posterior ventricular septal defects should be removed, and the ventricular septal defect should be repaired. Primary atrial septal defect. The right atrium incision was sutured. As for the complete atrial septal defect of type A and B classified by Rastelli, surgery is relatively easy. Firstly, the ventricular septal defect under the left upper and right upper lobe is repaired, and the valve is raised and fixed on the straight edge of the patch according to the length of the above two leaflets attached to the interventricular septum. After the mitral valve is completely closed, the original is repaired. Hair hole atrial septal defect. 3. Intermediate ventricular septal defect repair surgery Such defects can be divided into the following two types of surgery. (1) There is a large primary hole defect, complete mitral valve fissure and two atrioventricular annulus, but the atrioventricular valve is not completely fused with the lower interventricular septum and remains ventricular septal defect. Intraoperative examination of the shape and number of valvular ventricular septal defect, such as 1 to 2 localized defects, can be done from the ventricular septum, right ventricular surface to the mitral root, 1 or 2 with sutured sutures, The remaining surgical procedures are the same as those of the partial atrioventricular septal defect. More than 3 localized defects or large defects, especially in the lower inferior leaflets, there are many subvalvular fiber bundles attached to the ventricular septum, and should be replaced with complete atrioventricular septal defect repair surgery. (2) There is a common atrioventricular valve. This type of malformation also has a large primary atrial septal defect. After careful exploration in the operation, only one or two of the right ventricular surface were sutured to close the ventricular septal defect. The remaining surgical procedures are the same as those of the partial atrioventricular septal defect. 4. Bidirectional cavopulmonary bypass or total vena cava connection to the pulmonary artery The surgical procedure is the same as "tricuspid atresia". complication 1. Left atrioventricular valve regurgitation After surgery for atrioventricular septal defect, approximately 10% of patients develop left atrioventricular valve insufficiency. This is a common complication after this malformation and is the main cause of postoperative death. Early postoperative application to reduce post-cardiac load drugs such as sodium nitroprusside, nitroglycerin, etc.; long-term use of angiotensin-converting enzyme inhibitors such as captopril. There is a significant mitral regurgitation, and surgery must be performed at an early stage for repair of the left atrioventricular valve or mitral valve replacement. 2. Pulmonary hypertension crisis This crisis occurs in infants 6 to 9 months after birth and delayed withdrawal of tracheal catheters. Patients with complete atrioventricular septal defect were treated with phenoxybenzamine 1 mg/kg during cardiopulmonary bypass and rewarming, and 0.5 mg/kg once every 8 hours after surgery. After returning to the intensive care unit, the left atrial and pulmonary arterial pressures were monitored and sedative drugs were applied. Once the pulmonary hypertension crisis occurs, add anesthesia and muscle relaxant, high ventilation assisted breathing, so that the arterial blood carbon dioxide tension <25mmHg, intravenous infusion of prostaglandin E1 or the use of nitric oxide to reduce pulmonary vascular resistance. After 24 hours of smoothing, the ventilator can be removed. 3. Complete heart block has a high incidence of this complication in the past. Later, due to a detailed understanding of the anatomical location of the atrioventricular node and conduction beam and improved repair methods, the incidence decreased by less than 1%. Sometimes due to heart edema, temporary heart block is generated, temporary cardiac pacing is applied, and sinus rhythm is restored 24 hours after surgery. Permanent cardiac arrest should be placed in patients with permanent heart block. Sinus bradycardia often occurs after ventricular septal defect, and cardiac pacing can be temporarily used. The heart rate gradually returns to normal after 2 or 3 days. Sometimes there is a knot rhythm, especially in patients who have had a right maze with atrial fibrillation. The postoperative heart rate is slow, and temporary cardiac pacing is applied. The sinus rhythm is restored on the 3rd to 7th postoperative day. Frequent ventricular premature beats or ventricular tachycardia are rare, and once a continuous intravenous infusion of low-dose lidocaine occurs, it can be cured. 4. The right to left shunt after operation is due to the incomplete repair of the inferior horn of the primary atrial septal defect, so that the blood of the inferior vena cava returns to the left atrium, and should be repaired again. 5. Patients with residual ventricular septal defect after surgery have obvious indoor left to right shunt, and should be operated again in time. Heart failure occurred in the late stage, and the residual ventricular septal defect was closed after medical treatment.