Cerebral perfusion (CP) techniques were developed to reduce these risks. Prolonged hypothermic circulatory arrest (HCA) is associated with increased mortality, neurologic morbidity, and other complications. Most aortic arch repairs necessitate a period of systemic circulatory arrest combined with varying degrees of hypothermia to protect the brain and other vital organs. The arch is particularly challenging to repair because-unlike other aortic sections-its replacement usually necessitates interrupting both cerebral and distal aortic perfusion, leaving the brain, spinal cord, and other organs vulnerable. When significant coronary artery disease is identified in an elective surgical candidate, myocardial revascularization is recommended before aortic replacement. Additional investigation may include pulmonary function testing, cardiac stress testing, nuclear imaging, and coronary catheterization. The risk of stroke is significant during aortic arch repair, and because there is a well-known association between aneurysmal aortic disease and carotid artery stenosis, it is useful to perform a screening ultrasound of these arteries. Cannulation strategies may need to be adjusted in patients on the basis of preoperative findings, such as anomalies of branching arch vessels. The diameter of the aorta throughout the diseased and nonaneurysmal portions is determined, and potential sites for cannulation are reviewed for calcification, dissection, and mural thrombus. Common scenarios in which aortic dissection occurs include uncontrolled hypertension, connective tissue disorders (such as Marfan syndrome), and bicuspid aortic valve aortic dissection may cause cerebral malperfusion and result in symptoms such as syncope and neurologic deficits.Įxcept in those patients who require emergent repair, all patients should undergo a thorough preoperative evaluation emphasizing cardiac, pulmonary, and renal function, as well as a careful review of imaging studies. Arch aneurysms can rupture into the pleural cavity (usually on the left), mediastinum, esophagus, or tracheobronchial tree. New severe pain usually indicates aneurysm rupture or acute dissection. Chest wall compression can cause chronic dull or aching retrosternal or mid-scapular pain. Other problems that can arise from aneurysms involving the aortic arch and the adjacent segments include thromboembolic events such as stroke, and aortic valve regurgitation from associated root enlargement. Patients may have dysphagia from esophageal compression, respiratory symptoms due to airway compression, or edema of the upper body from superior vena caval compression. The onset of symptoms is usually considered an indication of impending rupture or significant malperfusion and should prompt urgent evaluation and repair. The aorta descends on the left.When specific symptoms are present, they are usually related to aneurysmal expansion and compression of surrounding structures or to malperfusion related to aortic dissection. There is no aortic arch in the normal location. Below: Frontal radiograph of the chest demonstrates the cervical arch at the apex of the left lung (white arrow) above the clavicles. Above: Axial, contrast-enhanced CT scan of the upper thorax shows the aortic arch (black arrow) extending above the level of the clavicles. Surgical treatment may be indicated for relief of tracheal and esophageal compression symptoms or for correction of associated vascular defectsĬervical Aortic Arch.Left-side lesions more often associated with coarctation.Right-sided lesions more often associated with intracardiac abnormalities like VSD or conotruncal abnormalities.Right-sided lesions have been associated with the 22q11.2 deletion syndrome.Buckling of the aorta from a pseudocoarctation may present a similar picture.Do not usually displace the trachea and esophagus forward.Aorta usually descends on the left (70%).Aortic knob appears at apex of left lung.Branching of major vessels may be mirror-image.Displace the trachea and esophagus forward.Right-side cervical arches usually descend on the left.Displacement of the trachea to the side opposite the arch.Right aortic arch and right descending aorta Ipsilateral descending aorta with normal sequence of brachiocephalic branching Haughton Classification of Cervical Aortic ArchesĬontralateral descending aorta and absence of one common carotid artery (separate external and internal carotid artery branches)Ĭontralateral descending aorta and presence of both common carotid arteriesĬontralateral descending aorta and bi-carotid trunk Usually defined as a supraclavicular position of the aortic arch.
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