Reconstruction of arch aneurysm under moderate hypothermia and separate carotid perfusion

Background. Aneurysmal involvement in the transverse aortic arch can be serious enough in most cases to lead to death from rupture. It also poses such potential problems that its treatment is one of the most formidable undertakings in cardiovascular surgery. Successful arch reconstruction depends on a reliable method to preserve cerebral, cardiac and visceral organs, avoid emboli, control postoperative hemorrhage and ensure a durable replace of the diseased aorta. Methods and Results. Between January 1990 and December 1993, 19 patients underwent surgical treatment at the Veterans General Hospital-Taipei for this aneurysm by use of a cardiopulmonary bypass technique with separated cerebral perfusion, moderate hypothermia (26° to 28°C) and topical cooling with cardioplegic infusion for myocardial protection. The 15 men and 4 women had a mean age of 59.85 ± 13.0 (35 to 76 years). The etiology of the aneurysmal disease was aortic dissection in 5 (Group I), and atherosclerotic aneurysm in 14 (Group II). Different types of arch reconstruction were performed under separated carotid perfusion. Pulmonary insufficiency was common in Group II (28.6%). Four patients had ruptured aortic aneurysm and external compression of broncheal tree with collapse of the lung before operation. Two patients developed renal insufficiency (14.3%). A patient in Group II had a minor stroke (7.1%) and died three months later of pneumonia with sepsis. There was one mortality (20%) in Group I because of postoperative, uncontrolled, massive bleeding. No other patient died of bleeding complications, except one (7.1%) in Group II who needed reexploration for checking postoperative bleeding. Follow-up period lasted for a mean of 25 months (range; 7 to 59 months). No evidence of cerebral or distal systemic embolization was apparent in survivors of the surgery. Conclusion. According to this limited experience, moderate hypothemia and separated cerebral perfusion proved to be valuable ajuncts and safe procedures to lower risk in the surgical treatment of the transverse aortic arch aneurysm.