ascending aortic aneurysm
Introduction
Introduction to ascending aortic aneurysm Most ascending aortic aneurysms are caused by cystic degeneration in the aortic wall. Most of the patients were young and middle-aged, often accompanied by aortic valve sinus and annulus enlargement. In the case of severe enlargement, the aortic valve leaflets cannot close together when the heart is dilated, showing aortic regurgitation. However, there is no obvious lesion in the aortic valve leaf itself. Some patients may have long heads, high arches on the upper jaw, trunk, limbs, slender fingers, excessive joint extension, chicken chest or funnel chest deformity, congenital eye lens dislocation and other signs of Marfan syndrome. Other causes of ascending aortic aneurysms include atherosclerosis, syphilitic aortitis and chest trauma. basic knowledge Sickness ratio: 0.0001% Susceptible people: mostly young, middle-aged Mode of infection: non-infectious Complications: spinal cord ischemia, renal failure
Cause
Ascending aortic aneurysm
Congenital factors (55%):
Congenital connective tissue abnormalities (ie, Ehlers-Danlos syndrome, Mafang syndrome - typically occur in the middle cystic necrosis, which affects the proximal aorta and can lead to typical fusiform aneurysms. Common thoracic aortic aneurysms The form is to widen the proximal aorta and aortic roots, leading to aortic regurgitation (aortic ring dilatation). About 50% of patients with aortic ring dilatation have horse syndrome or variations of the disease.
Disease factors (45%):
Most of the aneurysms caused by cystic degeneration in the middle are fusiform aneurysms. In the lesion segment, the ascending aorta is enlarged throughout the circumference, and the proximal end may involve the aortic annulus leading to aortic regurgitation; the distal end mostly ends below the beginning of the innominate artery. Muscle necrosis of the aortic wall elastic layer disappears, and often presents a cystic gap containing mucus-like substances. The intima may present with a localized tear and may also develop a dissecting aneurysm. A very small number of syphilitic ascending aortic aneurysms can be in the form of a bag, and the aneurysm is worn out from a weak area of the aortic wall. Generally, the neck of the bag, that is, the aortic wall is slightly broken.
Prevention
Ascending aortic aneurysm prevention
People need to be particularly peaceful, not to lose their temper, the more tempered, the easier it is to get cardiovascular disease. Have a good attitude. Usually exercise properly to improve your immunity.
Complication
Ascending aortic aneurysm Complications spinal cord ischemia and kidney failure
1. Major bleeding is the most dangerous complication of surgery, and it is also the main cause of death. Therefore, the use of imported artificial blood vessels or domestic artificial blood vessels to pre-coagulate with albumin can effectively prevent oozing blood of artificial blood vessels. Artificial blood vessels should be matched to the diameter of the aorta as much as possible to avoid anastomotic leakage. Vascular anastomosis is performed by continuous suture.
2, neurological complications is another serious complication of aneurysm surgery, the use of low temperature to protect the nervous system. The aortic root or the operation involving the arch is applied to the hypothermic cardiopulmonary bypass. The right subclavian artery cannula can be applied when the circulation is needed, and the selective cerebral perfusion can be performed. The descending aortic surgery can protect the spinal cord and the kidney by left heart bypass. Longer range, need to remove the longer aorta, the intercostal vascular should be anastomosed to the artificial blood vessel, use adrenal cortex hormone to protect nerve cells, strengthen perioperative management, control blood pressure before surgery to correct heart failure, pay attention to blood pressure during operation Control, especially before blocking the opening, should pay attention to blood pressure and circulation capacity, while correcting acidosis and electrolyte imbalance, to prevent cardiac arrest after opening blood pressure.
3. Most abdominal aortic aneurysms are located below the level of the renal artery. The abdominal aorta below the renal artery is less likely to have spinal cord ischemia or renal failure, but there may be a lower extremity blood supply disorder, so the abdominal aorta The blocking time should be as short as possible. 2% to 7% of abdominal aortic aneurysm surgery should be blocked above the level of the renal artery and even above the level of the celiac artery.
4, aneurysm surgery exposure range, long time, surgical trauma, low temperature and extracorporeal circulation have an impact on the body's immunity, so postoperative infection is easy, prevent all links that may lead to infection, and pay attention to the rational use of antibiotics, avoid antibiotics A double infection caused by improperness.
Symptom
Ascending aortic aneurysm symptoms Common symptoms Severe pain Aortic and pulmonary arteries partial vertebral artery Left ventricular hypertrophy Pulse pressure widened heart failure Water rushing thoracic deformity Aortic ring dilatation
Ascending aortic aneurysms that do not invade the aortic annulus may not present clinical symptoms in the early stages. When the aneurysm grows up and compresses the superior vena cava or the innominate vein, the neck and upper extremity veins swell and expand. In advanced cases, aneurysms grow up in the chest wall and erode the sternum, causing severe pain, or even wearing the chest wall, presenting a pulsatile mass. Aneurysmal lesions lead to aortic annulus enlargement, aortic valve insufficiency, clinical symptoms of congestive heart failure.
Physical examination can detect diastolic murmurs caused by aortic regurgitation, pulse pressure widening and water impulses. Chest X-ray examination revealed ascending aorta and left ventricular enlargement. Electrocardiogram examination often shows left ventricular hypertrophy and strain. Aortic angiography revealed ascending aorta and aortic valve sinus enlargement. The ascending aortic aneurysm caused by the middle cystic degeneration is mostly confined to the ascending aorta. From the beginning of the innominate artery, the outer diameter of the aorta is close to normal. With aortic regurgitation, the contrast agent returns to the left ventricle when the heart is diastolic. According to the amount of contrast agent reflux, the severity of aortic regurgitation can be determined.
Examine
Ascending aortic aneurysm
(1) X-ray plain film examination: can display calcified tumor wall.
(2) Arteriography: To determine the location, extent, size, etc. of the aneurysm, it is helpful to confirm the diagnosis and formulate the surgical plan.
(3) Ultrasound examination: the size, pulsation and noise of an aneurysm can be measured.
(4) Reactive hyperemia test: Observe whether the collateral circulation of the affected limb has been fully established.
Diagnosis
Diagnosis and differentiation of ascending aortic aneurysm
Thoracic aortic aneurysms are usually seen on chest X-rays. CT and MRI are particularly helpful in confirming their range and size. Transthoracic ultrasonography can accurately measure the size of the ascending aortic aneurysm, but not for the descending aorta, and both can be accurately measured by transesophageal ultrasonography. Most of the indications for thoracic aortic aneurysm before resection are aortic contrast angiography or magnetic resonance aorta angiography.
For syphilitic aneurysms, serum tests, especially the fluorescence T. pallidum antibody adsorption test and the Treponema pallidum immunoassay, were mostly positive.
