['There are few data on successful recanalization of acutely occluded modified aortopulmonary shunts in infants in whom the major component of pulmonary flow is shunt-dependent.', 'Seven infants (age range 6 days to 7 months) with modified (polytetrafluoroethylene) aortopulmonary shunts (central shunt n = 6, modified Blalock-Taussig shunt n = 1), in whom acute shunt occlusion was documented following surgery (interval from shunt surgery 2-6 days) underwent emergency cardiac catheterization with a view to reopening the shunt. Anterograde right ventricle to pulmonary artery flow was present in three patient; two other had additional aortopulmonary collateral vessels, and intravenous prostaglandin E (PGE1) infusion was restarted in three infants to achieve or maintain ductal patency. All occluded shunts could be crossed with a 4F endhole catheter and various guidewire combinations. Balloon dilation was performed using a balloon with the same nominal diameter as the shunt (5 or 6 mm).', 'All shunts were successfully recanalized. Two infants with recurrent cyanotic episodes underwent stent implantation in the right ventricular outflow tract (RVOT) during the same procedure. One infant required shunt revision 24 h following balloon angioplasty, during which a small clot was evacuated from the distal end of the shunt. An immediate improvement in oxygen saturation could be documented in all patients. In the remaining six infants, shunt patency was confirmed at follow-up, until further definitive repair. One infant died of non-cardiac causes, while awaiting definitive repair.'] Does transcatheter recanalization of acutely occluded modified systemic to pulmonary artery shunt in infancy?