Ventricular arrhythmias remain a challenge in the care of adults with congenital heart disease (ACHD). This Heart review1 outlines the current frameworks for arrhythmia management while drawing our attention to the knowledge gaps and opportunities to better inform ourselves about the development, presence and treatment of ventricular arrhythmias in ACHD.

The development of evidence-based guidelines in ACHD is particularly difficult for several reasons. Randomised controlled trials (RCTs) provide the foundation of data for most other cardiac guidelines; however, heterogeneity of diagnoses and physiological variations leads to relatively small populations in ACHD, which require long recruitment periods. Today, individuals also emerge from childhood surgery with a different footprint than those in prior decades, further complicating the interpretation, and relevance of past RCTs. Therefore, thorough observational studies have been crucial to the development of ACHD guidelines, and with consensus statements inform much of the ACHD literature.

As highlighted in this review, some recommendations mirror those in general cardiology, such as the management of acute ventricular arrhythmias, while drawing attention to the physiological differences in certain congenital diagnoses (such as lower resting blood pressure or hypoxia, possible meso-position or dextro-position of the heart) and the haemodynamic reserve and stability of some young patients despite ventricular tachycardia (VT). Similar to general guidelines, implantable cardioverter-defibrillators (ICDs) have …