The Aortic Uncrossing Procedure for Circumflex Aorta

Abstract

A‘‘circumflex aorta’’ is a rare vascular ring caused by a right aortic arch with a left ligamentum arteriosum and a descending thoracic aorta that crosses posteriorly from right to left above the level of the tracheal carina (Fig. 1). The trachea and esophagus are compressed from the right aortic arch, the left ligamentum, and the posterior crossing aorta causing the typical symptoms of noisy breathing, dyspnea on exertion, dysphagia, and frequent upper respiratory tract infections. Although ligamentum division would divide the ring, that alone would not relieve the compression produced from this abnormal vascular anatomy. The aortic uncrossing procedure was first reported by Drs Planch e and LaCoeur-Gayet 1 (Fig. 2). They also coined the term ‘‘circumflex aorta.’’ They performed the operation in 3 patients, all of whom had previously undergone ligamentum division and had persistent postoperative symptoms. 2 We now have experience with this operation in 4 patients. All vascular ring operations at our institution begin with a preoperative rigid bronchoscopy to assess for unsuspected additional tracheal pathology such as complete tracheal rings and to evaluate the extent and location of compression from the aorta. 3 A circumflex aorta would have both right-sided compression from the right aortic arch as well as posterior compression produced from the circumflex descending aorta. The ‘‘aortic uncrossing’’ procedure is performed through a median sternotomy with cardiopulmonary bypass, hypothermia, and a short period of circulatory arrest (Figs. 3-13). The heart is arrested with cardioplegia, head vessels are snared, and deep hypothermic circulatory arrest is established. The aorta is transected distal to the takeoff of the right subclavian artery and the proximal stump oversewn. The ligamentum arteriosum is ligated and divided. The right and left recurrent laryngeal nerves must be identified and preserved. The descending aorta is dissected from its posterior attachments and brought up on the left side of the ascending aorta. An arteriotomy is performed on the side of the ascending aorta adjacent to the left carotid artery. An anastomosis between the descending aorta and the arteriotomy is performed. The circulation is resumed and the patient is warmed and weaned from cardiopulmonary bypass. This procedure relieves both the posterior compression caused by the circumflex aorta and the right-sided compression of the trachea from the right aortic arch (Fig. 14).