A thoracic aortic diameter which is ? 50% greater than normal, is considered aneurysm (the normal diameter is dependent on the precise location). Most thoracic aortic aneurysms do not cause symptoms, although some patients have chest or back pain; Other symptoms and signs are usually the result of complications (eg. as dissection, compression of adjacent structures thromboembolism, rupture). The risk of rupture increases proportionally with the size of the aneurysm. The diagnosis is made by ultrasound or CT angiography. The treatment takes about an endovascular stent grafting or surgical.

Thoracic aortic aneurysms (TAA) account for a quarter of aortic aneurysms. Men and women are equally affected. About 40% of the TAA enter into the ascending thoracic aorta (from the aortic valve and brachiocephalic artery or innominate artery), 10% in the aortic arch (which A. brachiocephalic, the carotid arteries and the Aa. Subclaviae including), 35% in the descending thoracic aorta (distal to the left subclavian artery) and 15% in the upper abdomen (like thorakoabdominelle aneurysms).

A thoracic aortic diameter which is ? 50% greater than normal, is considered aneurysm (the normal diameter is dependent on the precise location). Most thoracic aortic aneurysms do not cause symptoms, although some patients have chest or back pain; Other symptoms and signs are usually the result of complications (eg. as dissection, compression of adjacent structures thromboembolism, rupture). The risk of rupture increases proportionally with the size of the aneurysm. The diagnosis is made by ultrasound or CT angiography. The treatment takes about an endovascular stent grafting or surgical. Thoracic aortic aneurysms (TAA) account for a quarter of aortic aneurysms. Men and women are equally affected. About 40% of the TAA enter into the ascending thoracic aorta (from the aortic valve and brachiocephalic artery or innominate artery), 10% in the aortic arch (which A. brachiocephalic, the carotid arteries and the Aa. Subclaviae including), 35% in the descending thoracic aorta (distal to the left subclavian artery) and 15% in the upper abdomen (like thorakoabdominelle aneurysms). TAA can dissect (aortic dissection) compress or erode into adjacent structures and cause thromboembolism, leak or rupture. Aneurysm of the ascending aorta sometimes affect the aortic root, causing aortic insufficiency or occlusion of the coronary artery ostia, which in turn lead to angina, MI, or syncope. Etiology Most TAA are caused by atherosclerosis. Risk factors for both include a persistent arterial hypertension, dyslipidemia and smoking; Additional risk factors for TAA are the presence of aneurysms elsewhere and older age (peak incidence at the age of 65-70 years). Congenital connective tissue diseases (eg. As Marfan syndrome, Ehlers-Danlos syndrome) lead to cystic medial necrosis. This is a degenerative change, which leads to TAA and aortic dissection (aortic dissection) and the widening of the proximal aorta and the aortic valve (anuloaortaler ectasia), which leads to an aortic valve insufficiency, become complicated. The Marfan syndrome is responsible for 50% of cases with anuloaortaler ectasia, but the cystic medial and its complications can arise in young people even if no congenital connective tissue disease is present. Infected (fungal) TAA caused by hematogenous spread of systemic or local infection (z. B. sepsis, pneumonia), by lymphangiitische scattering (z. B. in tuberculosis) or by a direct spread (eg. As in osteomyelitis or pericarditis) , Bacterial endocarditis and a tertiary syphilis are rare causes. TAA occur with some connective tissue diseases (e.g., B. temporal arteritis, Takayasu’s arteritis, granulomatosis with polyangiitis [Wegener’s granulomatosis]) on. A blunt chest trauma caused pseudoaneurysms (extramural hematoma due to blood, which has leaked through the torn aortic wall). Symptoms and signs Most TAA are asymptomatic until complications develop (eg. As thromboembolism, rupture, aortic regurgitation, dissection). However, the compression of adjacent structures can chest and back pain, cough, wheezing, dysphagia, hoarseness (due to a compression of the recurrent laryngeal nerve, or of the vagus nerve), chest pain (due to compression of the coronary arteries) and V. cava superior cause syndrome. The erosion of aneurysms in the lungs caused hemoptysis or pneumonia; Erosion in the esophagus (aortoesophageal fistula) causes massive hematemesis. A dissection manifested by tearing pain, often radiating to the back. Thromboembolism can stroke, abdominal pain lead (due to Mesenterialembolien), or limb pain. Patients who do not immediately die from the rupture of an aneurysm presenting with severe chest or back pain and hypotension or shock; Blood leakage takes place in the pleural or pericardial space most often. Additional characters are a Horner syndrome due to the compression of the sympathetic ganglia, a tactile pushing down the trachea with each cardiac contraction (tracheal tug), and deviation of the trachea. A visible or palpable Brustwandpulsation, occasionally prominent than the left ventricular pulse, are uncommon but occur. Syphilitic aneurysms of the aortic root cause classically for aortic regurgitation and an inflammatory stenosis of the coronary ostia, which may manifest as chest pain or myocardial ischemia. Syphilitic aneurysms not dissect. Diagnosis incidental findings on radiographs confirmed by CT angiography (CTA), magnetic resonance angiography (MRA) or transesophageal echocardiography (TEE) TAA are usually assumed for the first time when a chest x-ray absorption randomly shows a widened mediastinum or an enlargement of the Aortenknopfs. However, the chest x-ray recording a low sensitivity for TAA and provides no reliable screening method is (eg. As in patients with chest pain). These findings or symptoms that speak for an aneurysm should be tracked over the course of a three-dimensional imaging techniques. The CTA can describe the size of the aneurysm and the proximal and distal expansion, discovering a leak and simultaneously observe the existing pathologies. An MRA can provide similar details. A transesophageal echocardiography (TEE), the size and the extent of aneurysms of the thoracic aorta ascendens, but does not describe the descending aorta, and detect a leak; the TEE can fully visualize the thoracic aorta and is therefore particularly helpful in recognizing aortic dissection. A contrast angiography provides the best images of the arterial lumen, but no information on the extraluminal structure; the method is invasive and has a significant risk of renal and peripheral arterial embolism as well as for a Kontrastmittelnephropathie. The choice of imaging method depends on the availability and the local experience; However, when a rupture is suspected, a TEE or a CTA is carried out in dependence on the availability immediately. A widening of the aortic root or unexplained aneurysms of the ascending aorta require a serological investigation with respect to a syphilis. When a mycotic aneurysm is suspected, blood cultures are taken for bacteria and fungi. Forecast TAA have increased by an average of 3-5 mm / year, the risk factors for rapid expansion include a greater expansion of the aneurysm, the localization in the descending aorta and the presence of mural thrombi. The mid diameter at an aneurysm rupture is 6 cm for ascending aneurysms and 7 cm for descending aneurysms, but the rupture of smaller aneurysms may occur in patients with Marfan syndrome. The survival rate of patients with untreated major TAA is 65% after one year and 20% after five years. Endovascular Stent therapy transplantation or open surgery setting of hypertension If anatomically possible, the treatment should be an endovascular stent graft; in more complex aneurysms open surgery is performed. An immediate cessation of hypertension is essential. Untreated ruptured TAA are almost always fatal; they require immediate intervention as well as aneurysms with a leak and those that cause acute dissection or acute aortic valve insufficiency. The surgical procedure consists of a median sternotomy (for ascending aneurysms and Aortenbogenaneurysmen) or left-sided thoracotomy (for descending and thorakoabdominelle aneurysms) and subsequent excision and replacement of the aneurysm with a synthetic graft. Catheter-placed endovascular stent graft (endo-grafts) for the descending aorta are currently being used more often as a less invasive alternative to open surgery. With the emergency surgical care even the one-month mortality rate is 40-50%. Among patients who survive, the incidence of serious complications (eg. As kidney failure, lung failure, severe neurological damage) is high. Elective surgery has been for large aneurysms indicated (diameter> 5-6 cm in the ascending aorta,> 6-7 cm in the descending aorta and in patients with Marfan syndrome> 5 cm at each location) and also for aneurysms, the rapidly enlarge (> 1 cm / year). (Editor’s note:. Indication for surgery from> 5 cm in patients with Mafan Syndrome> 4.5 cm, s Guidelines of the European Society of Cardiology) Elective surgery is also indicated for symptomatic, traumatic and syphilitic aneurysms. In syphilitic aneurysms benzathine penicillin is 2.4 million units once / week i.m. postoperatively administered for three weeks. Tetracycline or erythromycin 500 mg for patients with a penicillin allergy p.o. four times a day acceptable for 30 days. Although the surgical treatment of an intact TAA improves the results, the mortality rate can be still 5 to 10% after 30 days and 40-50% after 10 years. The risk of mortality increases significantly if the aneurysms are complicated (eg. As in the aortic arch or in the thoracoabdominal aorta) or if patients have coronary heart disease, age and older are asymptomatic or have a pre-existing renal disease. The perioperative complications (eg., Stroke, spinal cord injury, kidney failure) occurs in 10-20%. Asymptomatic aneurysms that do not meet the criteria for an elective surgery, are used for aggressive blood pressure control with ?-blockers, and if necessary, other antihypertensive agents treated. It is essential to quit smoking. Frequent follow-up to check the appearance of new symptoms, as well as serial CT scans every 6-12 months are necessary in many patients. Key points The thoracic aortic aneurysm (TAA) is an increase of ? 50% of the diameter of the aorta. TAA can dissect, compress or erode into adjacent structures and cause thromboembolism, leak or rupture. The mid diameter at an aneurysm rupture is 6 cm for ascending aneurysms and 7 cm for descending aneurysms. The diagnosis is often first detected on the basis of a random X-ray or CT findings and confirmed by CTA, MRA or TEA. Small, asymptomatic TAAs are treated with an aggressive control of blood pressure and dyslipidemia, as well as smoking cessation. If anatomically possible, treating larger or symptomatic TAAs should be an endovascular stent graft; in more complex aneurysms open surgery is performed.

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