Cardiac catheterisations in paediatric patients are not without risk. This is independent from the type of catheterisation undertaken: diagnostic, interventional or electrophysiological studies all carry risks.1 Over decades, the risk decreased only marginally.2 Interventional cardiac catheterisations seem to have a higher complication rate than diagnostic procedures.2 ,3

Possible complications range from most severe (death, cerebral infarction, cardiac injury) to minor events like transient rhythm disturbances requiring no treatment.1 Age and patient size seem to be an independent risk factor for almost all types of complications, with the youngest patients being at the highest risk.1–3

The most frequently observed adverse events are vascular, namely arterial thrombosis, which accounts for almost one-third of all observed complications.1 Again, younger age …