Aneurysms of the innominate artery: surgical treatment of 27 patients.

1. Aneurysms of the innominate artery: surgical treatment of 27 patients. John D. Symbas, M.D., Michael E. Joseph B. Whitehead Department of Surgery, Division of Cardiovascular Surgery, Grady Memorial Hospital. J Card Surg 2005;20:455~459

2. Introduction • Aneurysms of the innominate artery (AIA) are widely considered to be a rare entity. We describe our experience with AIAs in the last three decades.

3. Methods • From October 1973 to October 2000, 27 patients were operated with an AIA. • The underlying cause of aneurysm was Takayasu's disease in 7 patients, degenerative disease in 6 patients, syphilis in 5 patients, chronic dissection in 3 patients, trauma in 2 patients, infection in 2 patients, a postoperative complication in 1 patient, and Marfan’s syndrome in 1 patient. • AIA was associated with an aortic aneurysm in 17 patients.

4. Fourteen patients had no symptoms. • The remaining patients had symptoms, with thromboembolic complications in 7 patients, pain without rupture in 3 patients, and a ruptured aneurysm in 3 patients.

5. In two patients at high risk for surgery who had a small AIA with embolic complications, a cervical approach was used as a means of performing distal exclusion and crossover bypass. • In the remaining 25 patients, a midline sternotomy was used.

6. Ten patients underwent a prosthetic replacement of the ascending aorta and/or aortic arch with a separate prosthetic branch to the innominate artery (IA). • Thirteen patients underwent ascending aorta-to-IA prosthetic bypass in association with lateral suture (8 patients) or prosthetic patching (5 patients) of the aorta.

7. One patient with an infected aneurysm was treated by means of resection of the aneurysm, proximal ligation of the IA, and transposition of the right into the left common carotid artery. • Cardiopulmonary bypass with deep hypothermic circulatory arrest was used in 10 patients.

8. Results • Three perioperative deaths occurred (2 of 4 in association with emergency treatment and 1 of 23 with elective treatment). • Respiratory complications requiring prolonged artificial ventilation developed in five patients. • Two patients had transient worsening of preoperative neurologic deficits. • Late results, with a mean follow-up of 85 months, were good.

9. Conclusion • The etiology and presentation of AIAs are variable. • In approximately 85% of the cases, the rupture occurs in the proximal segment of the artery, while 9% occur in the distal segment, and 3% occur in the middle segment.

10. The patients with an isolated innominate artery injury should undergo prompt operative repair. • Median sternotomy is the incision of choice for the repair of rupture with or without extension along the lower anterior border of the right sternocledomastoid muscle. • Graft interposition between the ascending aorta and the distal innominate artery or right common carotid and right subclavian arteries is a safer approach for this injury.

11. Prompt surgical treatment including resection of the aneurysm and adjacent necrotic tissue and bypass grafting to a distal vessel is indicated to minimize the risk of distal embolization or rupture. Surgical management with current cardiovascular techniques achieves excellent results.