Indications for repair include symptomatic aneurysms and aneurysms greater than 6 cm in diameter.
Operative management consists of tube graft replacement along with anastomosis of major branches to the graft. Aneurysms involving the thoracic and proximal abdominal aortic segments may be approached through a left posterolateral thoracotomy extended to the umbilicus. Left heart partial bypass (atriofemoral) is often used, both to protect the heart from overdistention andto provide distal blood flow while the aorta is clamped. Sodium nitroprusside may be given before cross-clamping to reduce proximal blood pressure, and cerebrospinal fluid drainage is used as an adjunct to decrease the incidence of postoperative paraplegia. The thoracic aorta is clamped and opened to perform the proximal anastomosis while visceral perfusion is maintained retrograde. The aorta is clamped distally opening the remaining aneurysm. The orifices of all major aortic branches are occluded with balloon catheters or vascular clamps. Temporary perfusion can be maintained to those branches during aneurysm repair by using balloon catheters connected to the atriofemoral bypass. The anastomoses of significant aortic branches to the graft are performed as an island patch or separate bypasses. The clamp is moved to the graft below the renal arteries to reperfuse all visceral vessels in a prograde fashion. The distal anastomosis is made either to the uninvolved aorta or to the iliac arteries.
