HOW TO DO IT
Management of Right-Sided Aortic Arch Aneurysms Barbara L. A. C. Robinson, MD, Edward M. Nadolny, CCP, Michael H. Entrup, MD, and Lars G. Svensson, MD, PhD Center for Aortic Surgery, Departments of Cardiovascular Surgery and Anesthesia, Lahey Clinic, Burlington, Massachusetts
Specific technical problems are associated with the management of patients who have either of the two types of right-sided arches and aneurysms of the aortic arch and descending aorta. Two different approaches to addressing these problems, depending on the predominant congenital vascular anatomy, are presented. (Ann Thorac Surg 2001;72:1764 –5) © 2001 by The Society of Thoracic Surgeons
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pecific technical problems are associated with the management of patients who have either of the two types of right-sided arches and aneurysms of the aortic arch and descending aorta [1, 2]. We present two different approaches of addressing these problems depending on the predominant congenital vascular anatomy.
Technique The first patient had a right-sided aortic arch with aberrant left subclavian artery from the descending aorta (Felson and Palayew type 2) [3]. This patient was 40 years old and had been treated since childhood for wheezing. After admission for pneumonia, bronchoscopy showed a pulsatile compression of the right bronchus. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated the origin of the aneurysm to be in the distal aortic arch, extending into the descending aorta with a large Kommerell’s diverticulum, including an aberrant left subclavian artery. The trachea and right bronchus were compressed between the posterior aberrant left subclavian artery and the anterior aorta (Fig 1). Initially, a left subclavian artery to left common carotid artery bypass was performed. Then, through a right thoracotomy, hypothermic circulatory arrest was achieved with cannulation of the ascending aorta and the right atrium while flooding the operative field with carbon dioxide [4]. The distal aortic arch and descending aorta were then replaced with a no. 26 double-velour woven Hemashield graft, the Kommerell’s diverticulum was resected, and the aberrant left subclavian artery stump was oversewn. Postoperative bronchoscopy confirmed mild residual external compression. Recovery was without incident (Fig 1). The patient no longer had wheezing on subsequent follow-up, but did have one episode of right lower lobe pneumonia. The second patient had right-sided aortic arch with vascular ring (Felson and Palayew type 1) [3]. This patient was a 58-year-old man with dysphagia. The right-sided arch and aneurysmal (6 cm) posterior aorta were the dominant vascular anatomy with the esophagus and trachea displaced anteriorly. In addition, an aberrant Accepted for publication June 13, 2001. Address reprint requests to Dr Svensson, Lahey Clinic, 41 Mall Rd, Burlington, MA 01805; e-mail:
[email protected].
© 2001 by The Society of Thoracic Surgeons Published by Elsevier Science Inc
left-sided type of innominate artery arose from the ascending aorta and crossed anteriorly to the trachea and esophagus before bifurcating into the left common carotid and left subclavian arteries with adherence of these latter two vessels to the descending aorta (Fig 2). In addition, there was a sclerosed ductus arteriosis between the descending aorta and the pulmonary artery compressing the trachea and esophagus. A left thoracotomy was performed with antegrade perfusion through the right subclavian artery and venous drainage through the right femoral vein from the right atrium. With deep hypothermic circulatory arrest, the trachea and esophagus were lifted anteriolaterally and the anastomosis performed to the ascending aorta, to the right of the vertebral bodies, using a 24-mm tube graft. This was done to ensure aneurysmal decompression of the more anterior lying esophagus and trachea (Fig 2). The ductus arteriosis was divided to further free up the trachea and esophagus. The patient was extubated on the second postoperative day, but required surgical reexploration for bleeding. His dysphagia resolved.
Comment Although an aberrant right subclavian artery coming off the Kommerell’s diverticulum on a descending aorta is more common, the mirror image anatomy with a rightsided aortic arch with Kommerell’s diverticulum and aberrant left subclavian artery also occurs [1, 2]. Felson and Palayew [3] classified this variant as a type 2 rightsided aortic arch. The Kommerell’s diverticulum and aberrant left subclavian are a remnant of the left dorsal arch and the right-sided fourth aortic arch and the dorsal aorta persists. We consider it useful to use deep hypothermia with circulatory arrest for type 2 right-sided aortic arch repairs because the innominate artery and left common carotid artery origins can be variable. Also, the aorta is often very friable, particulately if the patient is being treated with steroids as in our patient. Patients with type 1 right-sided arches have a vascular ring resulting from reabsorption of the left fourth aortic arch, right dorsal aorta reabsorption, and a right-sided fourth arch that joins the left dorsal aorta. Adequate decompression of the esophagus and trachea can be a challenge. Of interest, in our patient we had expected that the anterior aberrant left-sided innominate, common carotid, and subclavian arteries would communicate with the adherent descending aorta but that was not found during circulatory arrest. A right-sided approach in this patient would not have alleviated the compression nor would a mediastinal approach have given access to repair the posterior aortic arch and descending aneurysms because the trachea and esophagus lay anterior to the aneurysm. Thus we chose a left thoracotomy even though we realized that the anastomosis would have to be done in the right chest and to the right of the vertebral bodies. 0003-4975/01/$20.00 PII S0003-4975(01)02983-6
Ann Thorac Surg 2001;72:1764 –5
HOW TO DO IT ROBINSON ET AL RIGHT-SIDED AORTIC ARCH ANEURYSMS
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Fig 1. (A) Computed tomography scan showing compression of trachea. (B) Diagram of anatomy. (C) Postoperative diagram. (D) Postoperative magnetic resonance angiography scan.
With reperfusion of the brain through the right subclavian artery, we were then able to test the anastomosis and ensure that there was complete hemostasis at the proximal anastomosis. The small tube graft allowed for complete decompression of the esophagus and trachea. The recurrent laryngeal nerve was well visualized and preserved, and the patient had no hoarseness.
References
Fig 2. Diagram of anatomy.
1. Svensson LG, Crawford ES. Congenital abnormalities of the aorta in adults. In: Svensson LG, Crawford ES. Cardiovascular and vascular disease of the aorta. Philadelphia: WB Saunders, 1997:153–74. 2. Lee R, Maughan RE, Svensson LG. Elephant trunk reconstruction for aberrant right subclavian and aortic aneurysm. Ann Thorac Surg 1997;64:547– 8. 3. Felson B, Palayew MJ. The two types of aortic arch. Radiology 1963;81:745. 4. Nadolny EM, Svensson LG. Carbon dioxide field flooding techniques for open heart surgery: monitoring and minimizing potential adverse effects. Perfusion 2000;15:151–3.