This week we delve into the world of interventional cardiology and congenital heart surgery when we review a recent report from the team at Toronto Sick Children's Hospital about their experience with interventions in the pulmonary arteries following the arterial switch operation. How often are branch or main pulmonary artery narrowings serious enough to warrant intervention? What degree of RV pressure should warrant a cath or intervention? How commonly did simple balloon dilation result in a meaningful degree of reduction in pulmonary artery obstruction and/or RV pressure? How commonly were complications observed? These are amongst the questions reviewed this week with the work's first author, senior cardiology fellow at the University of Toronto, Dr. Michael N. Gritti. https://doi.org/10.1007/s00246-024-03408-w