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intervention, and complexity of the anatomy Generally, earlier debate has given way to a preference in most centers for performing surgery at or shortly after presentation at any age This is supported by a lower incidence of late hypertension when repair is undertaken early There have been reports of a higher incidence of recoarctation with earlier repair, but with advances in technique, many large studies show an acceptable rate of recurrence even with neonatal repair Similarly, for interrupted aortic arch, most patients should be medically stabilized before being taken to the operating room for definitive repair within several days of their presentation Although these infants are seldom operated on electively, there is rarely a need to rush a patient to the operating room before correction of the numerous metabolic abnormalities that occur as the ductus closes unless the patient does not respond to prostaglandin treatment In adults found to have interrupted aortic arch, it is preferable to repair the arch unless the patient elects for medical management.40 Strategies for Surgical Treatment Surgical Management of Simple Coarctation Resection and End-to-End Repair The era of coarctation repair started during the Second World War, when Blalock performed the first experimental repairs using the turned-down left subclavian artery technique.89 Gross, in Boston, had also demonstrated experimentally that resection with end-to-end anastomosis was feasible.90 The first end-to-end coarctation repair including resection was performed by Crafoord in Stockholm.91 A slight modification of this original technique, the extended end-to-end repair, is the most commonly practiced technique currently After excision of the coarctation, an incision on the aortic arch is extended proximally on the underside of the arch to underneath the carotid ostia and a matching incision on the distal aorta is completed laterally so that it can slide under the distal arch This technique has consistently excellent outcomes with low mortality and a low incidence of recoarctation or aneurysm formation This repair can address distal arch hypoplasia between the left carotid and left subclavian arteries as well Modifications of the technique have been suggested, including the combination of resection and end-to-end repair with a subclavian flap angioplasty Recent reports suggest this to be a safe technique when used in infants, producing no mortality and very good resolution of the gradients.92 There are as yet no proper randomized controlled trials comparing the many techniques used for surgical repair Because of this, retrospective studies are used to provide the evidence required to guide optimal treatment Most studies seem to find a lower incidence of recoarctation and aneurysm formation after some form of end-to-end anastomosis.93 Left Subclavian Patch Aortoplasty Initial reports of a high incidence of recoarctation with end-to-end repair in infants, probably secondary to leaving residual ductal tissue, caused surgeons to develop still other approaches The conception of the left subclavian patch aortoplasty by Waldhausen and Nahrwold in 1966 eliminated the concern of the circumferential anastomosis with end-to-end anastomosis and the obstruction caused by early use of interposition grafts.94 It has undergone modification since its introduction to improve results and is not widely practiced, but it is used by many for certain situations such as extreme low birth weight, inability to mobilize the aorta well, and the need to minimize clamp time This technique (Fig 45.19) consists of mobilization of the subclavian artery through a standard left thoracotomy and ligation of the subclavian artery at its first branch Care should be taken to preserve the thyrocervical trunk and the internal thoracic artery in order to improve perfusion to the left arm.95 The vertebral artery should be ligated to prevent subsequent subclavian steal, leading to cerebral ischemia The reported benefits of using this technique over others include the use of exclusively native material, with a consequent decreased risk of infection, and improved potential for growth,95 no circumferential anastomosis, less extensive dissection, and less tension on the suture lines compared with the end-to-end repair FIG 45.19 Subclavian flap aortoplasty The dotted lines show the site of initial surgical incisions into the narrowed arterial pathways The obvious disadvantage is the loss of the main arterial supply to the left arm, and deleterious effects on growth of the arm have been reported These range from mild discrepancy in length of the arm, similar to that following a Blalock-Taussig shunt, to rare reports of gangrene.96–98 Attempts have been made to address the loss of the subclavian artery using techniques involving reimplantation99,100 or use of the internal thoracic artery to preserve the arterial supply to the arm.101 Aneurysms have also been described102 but are less
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