Resection of constricted segment and grafting of artificial blood vessel

This operation is mainly for patients with aortic stenosis, congenital aortic coarctation is a more common congenital vascular malformation, accounting for 7% to 14% of congenital heart disease. The narrowing is mostly located in the aortic isthmus, the distal part of the left subclavian artery, and can usually be divided into a pre-catheter type and a post-catheter type. The former is also known as the infant type, the constriction is located at the proximal end of the arterial catheter, and the distal end of the left subclavian artery is often accompanied by patent ductus arteriosus. The latter is also known as the adult type. The constriction is located at the distal end of the arterial catheter or arterial ligament and distal to the left subclavian artery. In most cases, the arterial catheter is closed. A small number of patients can be narrowed in the thoracic aorta or descending aorta diaphragm plane or below the renal artery. Treatment of diseases: aortic stenosis with regurgitation congenital aortic coarctation Indication Constriction resection and vascular grafting are suitable for: 1. The narrowing range is long, and the end-to-end anastomosis cannot be performed after the resection. 2. The aortic wall has degenerative changes and should not be used for end-to-end anastomosis. 3. Intraoperative aortic injury is difficult to suture the repair. Preoperative preparation 1. Children with congestive heart failure should be treated with oxygen and cardiac diuresis to control heart failure. 2. Severe heart failure with acidosis and insufficient circulation of the body should be mechanically assisted breathing, input sodium bicarbonate to correct acidosis. Prostaglandin E can be applied at a dose of 0.1 g/(kg·min). To expand the patent ductus arteriosus to expand systemic perfusion. Patients with renal failure should undergo dialysis before surgery to correct electrolyte imbalance. 3. Choice of basic methods When aortic constriction is performed surgically, it is often necessary to block the descending aorta of the upper and lower ends of the constricted segment. In order to protect the spinal cord and distal organs from ischemic damage during the blockage of the descending aorta, low temperature, temporary vascular bridge and left heart bypass are also used. (1) Low temperature: After general anesthesia, the body surface is cooled to about 32 °C. The application indications were: 1 adult patient; 2 collateral circulation dysplasia; 3 aortic or intercostal artery formation near the narrowing segment; 4 re-narrowing the second operation. Dubost used superficial hypothermia in 900 patients with aortic coarctation, and only 1 patient developed transient spinal cord injury after surgery. (2) Temporary vascular bridge: a temporary vascular bridge that descends the narrow section of the main artery at the upper and lower ends of the narrowed section to communicate and block the blood circulation of the upper and lower ends of the descending aorta. After the operation, the blood vessel is removed, and the method is simple, and the spinal cord and the abdominal organs can be effectively protected during the operation. DeBakey is used to narrow down the second surgery and difficult cases. No spinal cord damage occurred. (3) Decompression of left heart perfusion: The advantage of this method is that it is easy to operate, can protect the spinal cord and abdominal organs, and can adjust the flow according to the blood pressure of the upper limb at any time, so as to avoid cerebrovascular accident due to high blood pressure in the upper body. The application indications are: 1 the length of the narrowed segment is long; 2 the collateral circulation is poorly developed, the distal pressure drops below 50 mmHg after the descending of the descending aorta; 3 the intercostal artery must be ligated; 4 the descending aorta After the blockage, the proximal pressure rose to above 200 mmHg; the descending aorta near the narrowed section showed a tumor-like dilation. Surgical procedure 1. The left intercostal space of the fourth intercostal space is inserted into the chest. 2. Cut the mediastinal pleura longitudinally along the descending aorta. 3. Free descending segment of the descending aorta. 4. Ligation of the arterial catheter. 5. Place the non-traumatic blocking forceps and remove the stenotic aorta. 6. Select the artificial blood vessel of the same caliber and suitable length for end-to-end anastomosis with the proximal end of the descending aorta. 7. End with the distal end. 8. Stitch the mediastinal pleura. complication 1. Bleeding: often due to thickening of the intercostal artery or expansion of the tumor, caused by suture detachment or rupture of the vessel wall after ligation, or due to the degeneration of the vascular wall caused by suture separation of the anastomotic site, immediate chest exploration Stop bleeding. 2. Postoperative abnormal hypertension: the incidence rate is 5% to 10%. The postoperative upper and lower extremities blood pressure was higher than that before surgery, while the aortic blood flow was not obstructed, and the cause was unknown. More common in patients with collateral circulation dysplasia, or older patients at the time of surgery. In severe cases, blood pressure can rise to 180 ~ 200mmHg. Vasodilators should be given blood pressure to relieve heart and brain load and avoid cerebrovascular accidents. 3. Re-narrowing: The incidence rate is different in the literature. The incidence of re-narrowing of the incision-end-end anastomosis in infants and young children is significantly higher than that in the left subclavian artery. The reasons for further narrowing are: 1 insufficient resection of the narrowing section; 2 anastomotic failure does not increase with the growth and development of infants and young children, especially the use of continuous suture to limit the growth of the anastomosis; 3 residual duct tissue, the duct tissue contains muscle fibers And extended to the aortic wall, when it is fibrotic, can cause re-narrowing; 4 anastomotic embolization should be corrected again. 4. Spinal cord ischemic injury: The incidence rate was 0.41%. Causes and no effective protective measures were taken during the operation; collateral circulation was poorly developed; spinal cord vascular variability and ligation were related to intercostal arteries. Spinal ischemic damage manifests as mild paralysis of the lower extremities, complete paraplegia, Brown-Sequard damage, and the like. 5. Abdominal pain: The patient may have abdominal discomfort after surgery for several days and gradually recover. A small amount of abdominal pain is obviously accompanied by abdominal distension and weakened bowel movements. It should be fasted, rehydration and gastrointestinal decompression. In severe cases, intestinal necrosis or intra-abdominal hemorrhage due to mesenteric arteritis should be explored by laparotomy.

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.