How to evaluate resting ECG and imaging in children practising sport: a critical review and proposal of an algorithm for ECG interpretation

The athlete's heart is a well-known phenomenon in adults practising competitive sports. Unfortunately, to date, most of the studies on training-induced cardiac remodelling have been conducted in adults and the current recommendations refer mainly to adult individuals. However, an appropriate interpretation of resting ECG and imaging in children practising sports is crucial, given the possibility of early detect life-threatening conditions and managing therapy and eligibility to sports competitions in the rapidly growing paediatric athlete population. While several articles have been published on this topic in adult athletes, a practical guide for the clinical evaluation of paediatric athletes is still missing. In this critical review, we provided a comprehensive description of the current evidence on training-induced remodelling in paediatric athletes with a practical approach for clinicians on how to interpret the resting 12-lead ECG and cardiac imaging in the paediatric athlete. Indeed, given that training may mimic potential cardiovascular disorders, clinicians evaluating children practising sports should pay attention to the risk of missing a diagnosis of a life-threatening condition. However, this risk should be balanced with the risk of overdiagnosis and unwarranted disqualification from sports practice, when interpreting an ECG as pathological while, on the contrary, it may represent a physiological expression of athlete's heart. Accordingly, we proposed an algorithm for the evaluation of normal, borderline, and abnormal ECG findings that can be useful for the readers for their daily clinical practice.