The most common cause of aortic arch aneurysm is senile atherosclerotic ascending aorta and arch aneurysm, followed by Marfan’s syndrome combined with arch aneurysm and bifid aortic valve malformation combined with ascending aortic aneurysm involving the arch, while simple arch aneurysm is extremely rare. However, the number of atherosclerotic ascending aortic and arch aneurysms is relatively low due to the low age of the operated cases in this group. Since type A aortic coarctation involves the arch, arch surgery is usually required during surgery, therefore, cases requiring arch surgery are mainly type A aortic coarctation, and such cases account for 78.7% in this group. Foreign literature reports that 70% of patients undergoing aortic arch surgery are type A entrapment cases [4]. Wang Jun, Department of Thoracic Surgery, Shanghai Changhai Hospital The most critical issue in aortic arch surgery is effective intraoperative cerebral protection. The most commonly used methods are DHCA + RCP and DHCA + SCP. 54 of the 74 DHCA patients in our group were treated with RCP for a maximum duration of 86 min. only one case had intracranial punctate hemorrhage confirmed by CT examination after surgery due to transient shallow coma, which may be related to high venous pressure during RCP. 20 cases were treated with DHCA + SCP for a maximum duration of 120 min. Transient postoperative psychiatric abnormalities were not significantly different in 6 cases (11.1%) in the former and 2 cases (10%) in the latter. The literature reports that the safe duration of cerebral protection by DHCA + RCP can be extended to 90 min [5], however, the effectiveness of this method of cerebral protection is still controversial. In our experience, DHCP + RCP is still a safe method for performing aortic arch surgery if the duration of arch surgery does not exceed 70 min, and the clinical results are similar to those of DHCA + SCP. However, if complex root surgery is performed, especially when partial branch vascular anastomosis of the aortic arch is required, DHCA + SCP should be chosen to ensure effective cerebral protection, and in one case in our group, the DHCA time was as long as 120 min, and the postoperative neuropsychiatric recovery was excellent. Because the effect of DHCP + SCP for cerebral protection is really effective, some authors stopped circulation for SCP when cooling to nasopharyngeal temperature of 25°C and anal temperature of 30°C to significantly shorten the cooling and rewarming time [6], although the initial clinical application results are satisfactory, we believe that for complex aortic arch surgery or those who estimate a long arch surgery time (>60 min), cooling to standard temperature should still be performed, which not only conducive to enhancing brain protection, but also to ensure the protection of important organs such as spinal cord, liver and kidney by hypothermia. The surgical approach to the aortic arch must be based on the cause, nature, and extent of the lesion. For true aneurysms, the surgical approach is based only on the extent of the aneurysm, whereas for type A aortic coarctation, the arch surgery must be based on the location of the endothelial rupture. If the endothelial rupture is limited to the ascending aorta, the ascending aorta and half arch replacement are generally performed; if the endothelial rupture is in the small bend of the arch, only the ascending aorta and half arch replacement are performed; if the endothelial rupture is located in the large bend side of the arch or the branch vessels have been involved, full arch replacement must be performed; however, in some cases with small endothelial ruptures, endothelial rupture repair and half arch replacement can be performed. However, this method must be applied to repair the endothelial rupture reliably and reliably, otherwise it will lead to further expansion of the endothelial rupture. When type A coarctation is accompanied by a proximal endothelial rupture of the descending aorta, we applied three surgical methods: first, we applied elephant trunk surgery to seal the endothelial rupture using an artificial vessel placed in the true lumen of the descending aorta (10 cases), and this method was reported in the literature to allow thrombosis of the descending aortic coarctation in 70% of patients after surgery, avoiding reoperation [7]; second, we applied felt pieces to repair the endothelial rupture of the descending aorta ( 3 cases), but this method can only be applied to cases with small fissures, which otherwise cannot be properly repaired [8]; third, the application of intraoperative artificial vascular stents (6 cases), in which the diameter of the descending aorta is first measured intraoperatively and an artificial vascular stent 1 to 2 mm larger than this diameter is selected for implantation into the descending aorta to seal the intimal rupture, and this method is currently considered the simplest and most effective method [9]. Since nearly 30% of cases of DeBakey type I aortic coarctation have a proximal rupture of the descending aorta, descending aortic coarctation is still present in 30-50% of cases after performing a hemi-arch replacement or total arch replacement alone. Based on these factors, in the past year we have routinely placed intracavitary stents in patients with DeBakey type I coarctation and performed only hemi-arch replacement for those without intimal dissection in the arch, while performing total arch replacement for those with intimal dissection in the arch or intimal dissection in the descending aorta near the subclavian artery. We are still following up on whether this approach helps to promote thrombosis in the descending aorta to avoid secondary surgery, and we will have more definite conclusions as the number of cases increases. The mortality rate of aortic arch surgery is about 10%, but when the arch surgery is performed with acute type A coarctation, the mortality rate reaches 20%. In our group, the total surgical mortality rate was 6.7% in 75 cases, among which 28 cases were operated in emergency or limited time due to acute entrapment or acute heart failure, and 4 cases (14.3%) died, while 47 cases were operated electively, and the surgical mortality rate was only 2.1%. The main reason for the relatively low operative mortality rate in this group may be related to the lower age of the patients (mean of 49.3 years in this group) compared to that reported in foreign literature. The main postoperative complications were respiratory insufficiency and renal insufficiency. The main cause of respiratory insufficiency may be related to DHCA and also to long-term preoperative smoking in most patients. While renal insufficiency is related to aortic coarctation, it is also related to preoperative long-term hypertension as well as DHCA. In terms of postoperative management, attention must be paid to preoperative basal blood pressure, and when postoperative blood pressure is controlled at a lower level (100-120 mmHg), for those with preoperative long-term hypertension, they are often prone to inadequate renal perfusion, which affects urine output and renal function. In addition, nine cases in this group developed neuropsychiatric complications after surgery, but they were mainly psychiatric abnormalities, and only one case proved to have intracranial punctate hemorrhage. Therefore, when DHCA and RCP are applied, the right jugular venous pressure must be strictly controlled ≤ 25 mmHg. For those with postoperative psychiatric symptoms, they can generally be cured without sequelae by applying symptomatic treatment.