Endovascular aneurysm repair (EVAR) is a technique that uses a stented artificial vessel graft, usually through a small incision in the iliofemoral artery, to access the aortic lumen using an interventional technique. It is delivered to the aortic lumen at a predetermined location and released to close the rupture of the coarctation in the aortic lumen, open the true lumen of the aorta and the branch arteries, and close the flow of the coarctation. Compared with the open surgical method, it has the advantages of less trauma, lower perioperative mortality and rapid recovery. It is mainly used in the treatment of Stanford type B clot, with satisfactory efficacy, and is currently recognized as the treatment of choice for type B clot. In contrast, EVAR treatment has been carried out in a few units for Stanford A type of entrapment, but there is no dedicated device yet, and the efficacy is in the process of follow-up. 2. Pre-surgical evaluation Pre-surgical evaluation of the aorta for endoluminal repair of aortic coarctation is first performed. Aortic CTA is generally performed to get a full picture of the coarctation, focusing on the aortic caliber, location, size and number of coarctation fistulas, and to determine the type of stent graft based on the aortic measurement data. The state and course of the true and false lumen of the aorta should also be carefully observed, whether the blood supply of important branch arteries originates from the true or false lumen, and the changes in blood supply after closure of the fistula should be expected. The state of the access vessel, whether there are stenosis, occlusion, tortuosity, thrombosis, rupture, and other conditions affecting the introduction of the stent. The favorable access for surgery should be clarified before surgery to prevent intraoperative difficulties. 3, the choice of anesthesia The commonly used method is general anesthesia, which is conducive to the control of blood pressure during surgery, and can obtain clearer photographic images and a calmer and safer stent release process. For patients with strong tolerance, easy blood pressure control, uncomplicated lesions and willing to cooperate with the surgeon, local anesthesia can be considered to complete the operation. Some units are currently using intralesional anesthesia, which should be avoided as much as possible to prevent complications of intralesional bleeding because systemic heparinization is given during surgery. The commonly used surgical access is the femoral artery, and the iliac artery of good caliber, without severe tortuosity or stenosis, and easily accessible to the true cavity is generally used as the access vessel. The external iliac artery can also be used as an access vessel, and in some cases it can even be introduced in the abdominal aorta, but this is extremely rare. There are 2 ways to expose the vessels, one is the traditional straight femoral incision and the other is the superior inguinal oblique incision, which has a quick postoperative recovery, less pain and fewer lymphatic leaks. However, the surgical operation is slightly complicated and should not be chosen by those who are not technically skilled. 4.2. Finding the true lumen is an important surgical step in EVAR surgery. Generally, the catheter is not difficult to enter the true lumen in cases where the abdominal aortic coarctation is not wide and the caliber of the true lumen is superior, but in some cases of true lumen stenosis, especially when the true lumen of the abdominal aorta is severely stenosed by the presence of fistula, the catheter can easily enter the false lumen by mistake. Therefore, the catheter must be confirmed to be in the true lumen when it reaches the abdominal aorta before proceeding upward and continue to be angiographically confirmed in a different location above. The use of a pigtail catheter during the upstroke facilitates catheter travel in the true lumen and helps to prevent catheter entry into the fistula. After the catheter reaches the ascending aorta, the catheter is re-imaged to determine that the catheter is in the true lumen of the aorta before proceeding to the next step of the procedure. 4.3. Photographic method In the narrower true lumen of the aorta, a hand-pushed fluoroscopic image can be used to determine the catheter location. Aortography above the thoracic aorta is usually performed with a pigtail catheter and a high-pressure syringe with a common flow rate of 20 ml/sec and a total volume of 25-30 ml. For the imaging of the abdominal branch arteries, an orthogonal position is generally chosen, and for the imaging of the aortic arch, a left anterior oblique position is generally chosen, and the angle size should be corrected according to the patient’s different arterial arch angles to select the best angle. For bilateral vertebral arteries, the orthogonal position is usually chosen, and the amount of contrast can be reduced by showing both sides in one image. The fistula is located in the anterior, lateral, medial and posterior sides of the aorta. The fistula is located in the lateral side because the stent is fully expanded and the closure effect is good; if it is located in the medial side, there may be a small chance of internal leakage because the stent is in a stacked tile structure in the medial side. If the fistula is located anteriorly or posteriorly, it may be difficult to find the tangential position and there are difficulties in determining the fistula position, which should be determined according to the preoperative CTA images to prevent incorrect stent position. 4.4. Stent preparation The selection of stent should be evaluated before surgery according to the different conditions and changes in vascular anatomy to select a suitable stent. It is important to accurately measure the aortic caliber according to the CTA images to prevent errors that could result in incorrect stent graft selection. If a satisfactory cross-sectional image is not seen on the CTA film, the measurement should be performed on the CT machine. The general oversize of stent grafts is often in the range of 10% to 20%, however, each patient should be selected individually according to the status of the patient’s entrapment, such as patients in the acute phase, true luminal stenosis of the descending aorta, weak arterial wall, etc. The selection should be on the small side, and currently, it is clinically found that some cases have recurrent rupture at the distal part of the stent after surgery, so the oversize selection is generally in the range of 10% to Therefore, the oversize selection is generally between 10% and 15% most commonly, and in some cases even a ratio of less than 10% is used, and rarely a ratio of more than 20% is used. The correct judgment of the anchorage area plays an important role in the success of surgery, and it is very important to make detailed judgment based on preoperative CTA and intraoperative DSA images. 4.5, stent release There are two methods of stent positioning, the commonly used method is to place a pigtail catheter through the left or right radial artery puncture to the ascending aorta as a contrast catheter, which does not affect the process of stent placement and release; the other omits both this step, by passing through the true lumen up to the ascending aorta after the measurement catheter contrast, directly mark on the screen, and after rapid replacement of the exchange guidewire, enter the stent to The marker point is used as a marker to release the stent. This method generally requires a high level of experience and competence of the surgeon and is mostly used in simple cases and is not recommended for beginners. There are some differences in the way the stent is released and how the stent is positioned when it is opened, which may result in inaccurate positioning and displacement of the stent if the characteristics of the stent are not understood. Generally, the stent is slightly positioned forward to release the bare stent and most of the first section of the overlapping stent and then slightly withdrawn backward, and the stent is opened in a homeopathic manner after good contrast positioning. Individual models of stents will jump slightly backward after release, and there should be reserved space for backward retraction. Generally, cases with high and steep arch descending section and wide interlayer have a high chance of jumping backward. The caudal end of the pusher should be strictly fixed at the time of release to prevent the stent from moving backward. The stent should be released throughout as soon as possible after the positioning of the anterior end of the stent is completed. The aortic blood flow is blocked during this process, and a long dwell time may displace the stent downward under the push of blood flow. The stent caudal end should be opened slowly to prevent excessive force on the inner diaphragm when opening. 4.6. Treatment of special cases A second stent can be placed to correct the fistula if the fistula is too large and the stent graft is bulging into the fistula; a phase I closure of the subclavian artery can be considered if the fistula is too close to the left subclavian artery, and if there is obvious poor blood flow to the left upper extremity or vertebral artery theft a carotid-subclavian artery bypass can be performed to reconstruct blood flow; if the left side is dominant or a single vertebral artery, vertebral artery blood flow reconstruction should be performed first before Although the incidence of paraplegia after implantation of EVAR long-segment aortic endoluminal grafts is not high (about 10%), the consequences of complications are serious, and to prevent paraplegia, the transverse lumbar artery should not be closed unless very necessary, and the stent should not If the thoracic aortic fistula has been closed, but the true lumen of the abdominal aorta is still unsatisfactorily open and the branch arteries have poor blood flow, the use of a bare stent placed in the true lumen to enlarge its caliber can be considered to restore and maintain its unobstructed blood flow. Type II endovascular fistula mainly comes from the left subclavian artery and can be closed with a spring ring or blocker. The type II endovascular fistula mainly comes from the left subclavian artery and can be closed with a spring ring or blocker. With the rapid development of endovascular surgery in recent years, endovascular repair with overlapping stents has become the main treatment for Stanford type B aortic coarctation. This procedure has obvious advantages over traditional open surgery due to its low surgical trauma, low bleeding, few surgical complications and greatly reduced mortality, and is now trending to replace traditional open surgery and is recognized by most scholars. With the continuous improvement of medical devices, interventional techniques and hybridization techniques, the indications for the procedure have been expanded, such as: hybridization techniques to expand the proximal anchorage area of stents, interventional opening of true lumen and branch artery stenosis, and the use of blockers to seal the fistula below, etc. When performing endoluminal repair of Stanford B aortic coarctation, it is important to pay attention not only to the mastery of basic techniques, but also to the management of complex situations and uncertainties in order to obtain good results.