A left posterolateral thoracotomy in the fourth intercostal space is the approach most commonly preferred. A right thoracotomy is indicated if the left aortic arch is dominant, which occurs rarely.

The left lung is retracted anteriorly and inferiorly toward the diaphragm to bring into view the area of the aortic arch and ductus arteriosus or ligamentum. The parietal pleura is incised longitudinally on the anterior surface of the descending aorta and left subclavian artery. The pleural flap containing the vagus nerve and its branches is retracted anteriorly; meticulous dissection is carried out to identify the local anatomy precisely. The surgeon should be aware that pulling the nerve toward the pulmonary artery causes the recurrent nerve to lie along a diagonal course behind the ductus or ligamentum, thereby increasing the risk of injury to the nerve.

The aorta and ductus or ligamentum are then mobilized by sharp dissection. The ductus or ligamentum is divided after ligating both ends.

The smaller (usually left anterior) aortic arch is dissected free and divided between clamps. The ends are then oversewn with 5-0 or 6-0 Prolene suture in two layers (Figs. 17-2 and 17-3).