This week we review a recent survey study on the topic of junctional rhythm and sinus node dysfunction in the Fontan. How important is this finding in our Fontan patients? When should a patient with a Fontan undergo pacemaker insertion? Is the loss of AV synchrony the more important hemodynamic effect of junctional rhythm or is it chronotropic incompetence? Who should be considered for a possible endocardial, transvenous atrial pacemaker in the Fontan patient? These are amongst the questions posed to this week's guest, noted pediatric electrophysiologist and Professor of Pediatrics at OHSU, Dr. Seshadri Balaji.  https://doi.org/10.1007/s00246-023-03296-6