Atrial repair (Mustard and Senning operations) for complete transposition has been replaced in most paediatric cardiology centres by the arterial switch operation, which is performed in the first few days or weeks of life.1 Arterial switch avoids many of the major complications of atrial repair: sinus node damage results in loss of sinus rhythm, atrial arrhythmias, bradycardias, and the need for antiarrhythmic medication and pacemaker implantation.2 ,3Systemic (morphological right) ventricular dysfunction and failure, when it occurs, requires either heart transplantation or takedown of the original repair and conversion to an arterial switch operation.4 ,5 Late sudden death is not always related to these complications and is unpredictable.2 ,3 ,6 Systemic and pulmonary venous pathway obstruction can cause significant morbidity and mortality as does repeat surgery.7 Balloon dilatation and, recently, stent implantation have been used to avoid repeat surgery for pathway obstruction.8-11 A trend towards a “double switch” (Senning or Mustard operationand arterial switch or Rastelli procedure) in patients with congenitally corrected transposition (atrioventricular and ventriculoarterial discordance) and the occasional patient with complete transposition who is unsuitable for an arterial switch operation, suggest that these problems will not be restricted to patients from an earlier surgical era.12

Severe obstruction or occlusion of the systemic venous pathways leads to systemic venous hypertension, which, while occasionally asymptomatic, …