transposition, as part of the “double switch” procedure (see Chapter 38) Mustard and Senning Procedures These procedures involve removal of the atrial septum and redirection of the systemic venous pathways to the subpulmonary left ventricle and of the pulmonary venous blood to the systemic right ventricle In the Senning operation, this redirection of systemic venous blood is achieved by means of an infolding of the atrial walls, whereas in the Mustard operation this is achieved using synthetic or pericardial tissue One of the most popular modifications of the Mustard operation involved creation of a trouser-shaped baffle, with the legs anastomosed to the superior and inferior caval venous inflows.57 By the 1980s, such atrial redirection procedures were associated with early postoperative rates of survival exceeding 95%.58 Arterial Switch Operation An important impediment to the early success of anatomic correction was the requirement to relocate the coronary arteries The advent of coronary arterial bypass surgery in adults in the late 1960s and the development of microvascular techniques set the stage for coronary arterial translocation and, in turn, anatomic correction for the infant with transposition The first successful arterial switch operation was reported by Jatene and colleagues in 1975,52 in an older infant with an associated ventricular septal defect Despite initial increases in mortality related to this procedure compared with atrial redirection,59 others around the world quickly followed suit, such that by the early 1990s the arterial switch supplanted the atrial switch as the favored procedure in most institutions During the first decade of anatomic correction, the pioneers of the arterial switch undertook the operation in infants with associated ventricular septal defects, which were generally beyond the early neonatal period The first report of successful correction of a neonate with an intact ventricular septum appeared in 1984.60 It rapidly became clear that an important determinant of early outcome was the condition of the left ventricle prior to surgery, which determined its ability to support the systemic circulation afterwards Hence the introduction of two-stage repair for patients with a “deconditioned” left ventricle, with banding of the pulmonary trunk and, if required, placement of a systemic-to-pulmonary arterial shunt These first-stage procedures “trained” the left ventricle, in preparation for a subsequent arterial switch operation.61 This approach is still used in the treatment of the patient who presents late (discussed later) Another important modification to the arterial switch was introduced in 1981 Now widely referred to as the LeCompte maneuver, this involves the forward looping of the bifurcation of the pulmonary arteries over the divided aorta, leaving the neoaorta lying posteriorly (Fig 37.17, Video 37.4) Following this maneuver, the pulmonary trunk itself is positioned anteriorly, allowing its anastomosis with the original aortic root without creating anatomic distortion.62 This procedure is still incorporated by most surgeons performing the arterial switch operation FIG 37.17 Anterior view of the completed LeCompte maneuver using computed tomography scan with volume rendering technique The pulmonary arteries are brought anterior to the aorta to minimize distortion LPA, Left pulmonary artery; RPA, right pulmonary artery The procedure as currently performed involves the transection of the aorta and the pulmonary trunk The coronary arteries are then detached from the aorta, along with a 1- to 2-mm cuff or “button” of aortic tissue and transferred to the proximal end of the divided pulmonary trunk, thus forming the new aortic root, or the neoaorta Extreme care should be taken to avoid tension, torsion, or angulation of the relocated coronary arteries because proper translocation is known to be the most crucial factor for a successful outcome The defects in the original aortic root left subsequent to detachment of the coronary arteries are repaired with pericardium The LeCompte maneuver is performed The distal end of the divided aorta is then anastomosed to the neoaorta, thereby connecting the morphologically left ventricle to the systemic circulation The anastomosis of the pulmonary artery to the neopulmonary valve completes the procedure (Fig 37.18; Video 37.5) FIG 37.18 Typical postoperative appearance as seen by the surgeon after completion of the arterial switch operation The arterial switch is currently the procedure of choice for almost all neonates In the current era, the overall mortality is very low, with an operative mortality rate of 2.7% in patients with an intact interventricular septum and 5.3%