Definition Aortic aneurysm repair involves the removal of the dilated portion of the aorta and its replacement with an artificial vessel made of prepared polyester material to ensure continuity of blood flow in the aorta and all branch vessels. Purpose Aortic repair is used to treat aortic dilatation due to necrosis of the middle layer of the ascending aorta or atherosclerosis of the aortic arch and descending segments. Congenital defects of connective tissue are also risk factors for the development of the disease. Prior to the 1950s, syphilitic patients were prone to aortic aneurysms, and 50% of patients may have intra-aortic thrombosis or rupture, and dilatation greater than 10 cm should be surgically repaired. Epidemiologic statistics The typical population distribution of aortic aneurysms is male, with an average age of 65 years, with a history of aortic mesangial necrosis and atherosclerosis. Patients with a history of syphilis or blunt trauma are at higher risk. Congenital connective tissue disorders such as Marfan’s syndrome or Ehlers-Danlos syndrome require close monitoring. Given the persistent expansion of the aneurysm, all patients need to be monitored. Surgical treatment is recommended once the aneurysm exceeds 5.5 cm. When the diameter reaches 10 cm, the risk of rupture increases and surgery is the best treatment. Most patients have no conscious symptoms and often the aneurysm is detected during other tests. Description After general anesthesia, the sternum is incised to repair the ascending aorta, aortic arch, or thoracic aorta, while the abdominal aorta requires a straight incision in the abdominal wall. Depending on the site of the aneurysm, a deep hypothermic stop circulation cardiopulmonary bypass (arch segment), cardiopulmonary bypass (ascending segment) or left heart bypass (thoracic segment) can be performed. All procedures require anticoagulation, and heparin is commonly used to prevent thrombosis. The aorta is blocked to prevent blood flow into the aneurysm lumen, and the lumen is opened up to the normal arterial segment, which is used to anastomose the synthetic woven artificial vessel graft. Blood flow is restored to check that the suture is secure and tight, and if there is any blood leakage, a patch suture is required. At the end of the procedure, the incision is closed and a drainage tube is placed until it heals. Aortic aneurysms can involve either the aortic valve or the coronary artery. Once the aortic valve is involved, an artificial graft with an aortic valve can be replaced, and the coronary artery is reconstructed on the graft. Aortic arch aneurysms require reconstruction of the vessels in the arch: the innominate artery, the left common carotid artery, and the left subclavian artery. To shorten the operative time, these three vessels can be anastomosed as a separate segment (with the patient’s own portion of the aortic wall as a patch) to an artificial vessel graft. Thoracic aortic aneurysms require special attention to protect the blood vessels supplying the spinal cord. The protection of the spinal cord during repair still needs further exploration. Some surgeons believe that rapid implantation of a graft to restore blood supply is the best way to protect the spinal cord. During surgical repair, a bypass graft called a Gott diversion can be used to maintain a local regional blood supply. Left heart bypass serves the same purpose as Gott diversion, a mechanical pump to ensure a reliable blood supply to the abdomen as well as the lower extremities. Rapid graft anastomosis is used to restore circulation as soon as possible in abdominal aortic aneurysms, and reconstruction is also required on the graft if the renal artery is involved, as well as on the trunk abdominal artery, superior and inferior mesenteric arteries if they are involved. Finally, involvement of the bifurcation of the abdominal aorta and bilateral iliac arteries is also common, and a bifurcated prosthetic graft is used to reconstruct bilateral lower extremity blood flow. Diagnosis and preoperative preparation X-rays can provide an early diagnosis of aneurysms. Early diagnosis can be obtained by noninvasive transesophageal cardiography or ultrasound. Further tests such as MRI or CT can obtain further images of the aneurysm. To clarify the severity of the aneurysm, arteriography is recommended. It helps to assess the condition of the vessels and the aortic valve. Postoperative care Postoperatively, the patient is admitted to the ICU for observation, with continuous cardiac monitoring of blood pressure and cardiac function, administration of intravenous fluids, including blood products, and administration of medications to support cardiac function, and discontinuation of the ventilator once the patient returns to spontaneous breathing. The duration of intensive care is approximately 2-5 days, after which the patient can be discharged in 1 week. Risks Risks associated with general anesthesia (not risks associated with aortic aneurysm repair), in addition to risks of cardiopulmonary bypass. Risks vary depending on the site of aneurysm involvement. There is a higher chance of paraplegia with thoracic aortic aneurysm repair based on the fact that surgical repair will affect the blood supply to the spinal cord. Repair of arch and ascending aortic aneurysms affects the function of the coronary artery and aortic valve. Sternal infection can affect the time to recovery. Abdominal aortic aneurysm repair affects renal function, which will eventually improve or resolve. Distant complications of abdominal surgery include intra-abdominal adhesions, small bowel obstruction, incisional hernia, and in arch segment aortic aneurysms, deep hypothermic extracorporeal circulation can present a risk of brain injury. Regression Aneurysm repair can restore normal body circulation. Aneurysm-related pain can be relieved postoperatively. The risk of aneurysm rupture is eliminated. Fatal and Disabling Rates Since 1999, 15,000 deaths from HU aneurysms have been reported in the United States, with a 5-year survival rate of 13% without treatment. Multicenter studies for non-emergency abdominal aortic aneurysm repair have shown a mortality rate of 2-6% 30 days postoperatively, compared to 37% for emergency surgery. The incidence of paraplegia during the treatment of thoracic aortic aneurysms is 6-10%. Posterior recurrent nerve injury may present with left vocal cord paralysis. Multi-organ failure occurs in most cases of death. The most common of these is pulmonary failure, and if the aneurysm involves the upper renal artery, the incidence of renal failure ranges from 4-9%. There are more risks of cardiopulmonary bypass in aneurysm repair of the ascending aortic arch segment, including difficulty in hemostasis, left heart dysfunction, or myocardial dysfunction, and irreversible brain damage is also a risk. Cardiac dysfunction can occur in all patients with thoracic or abdominal aortic aneurysms, and the risk of bleeding increases when the number of anastomoses increases. 40-70% of deaths are associated with cardiac dysfunction and blood loss. Other treatment measures Endoluminal stenting is an alternative treatment to surgery, using minimally invasive techniques to avoid or reduce ICU time, often using basic and epidural anesthesia.