Aortic dissection and aortic aneurysm surgery.

During the last year, the role of noninvasive studies for aortic dissection--magnetic resonance imaging, computed tomography scanning, and transesophageal echocardiography--has become better defined. Both magnetic resonance imaging and transesophageal echocardiography are highly accurate in detecting aortic dissection. On transesophageal echocardiographic imaging of the ascending aorta, artifacts may be present that mimic an intimal flap (septum). These linear echo densities have characteristic features which distinguish them from a true intimal flap (septum). Their recognition is critical in avoiding false positive transesophageal echocardiography findings. The general consensus on operations for ascending aorta and aortic arch dissection is that patients should be operated upon immediately. Controversy still remains, however, as to whether the aortic arch needs replacement at the time of the ascending and proximal aortic arch repair. Most authors agree that deep hypothermia with circulatory arrest is the preferable technique for acute aortic dissection repair and for surgery on the aortic arch in adults. Retrograde perfusion of the jugular veins is an added advantage. For acute aortic dissection involving the descending thoracic or thoracoabdominal aorta, evidence continues to accumulate that initial medical therapy with beta-blockers and antihypertensives is the preferable mode of treatment unless complications requiring surgery arise. Percutaneous techniques are increasingly being described, including fenestration of the aortic dissection septum, stenting of the aorta or aortic branches, and insertion of intraluminal aortic tube grafts. The safety of surgery on the thoracoabdominal aorta and on the descending thoracic aorta, including the prevention of complications, is reviewed.