Sudden cardiac death is a truly catastrophic, emotional event in the paediatric athlete and devastating for families of victims, peers, clubs and the sporting community as a whole. A death is often the result of a heart condition detectable by an electrocardiogram (ECG) (graphical display of the hearts electrical activity). The ECG is used as a first line tool in cardiac screening across sports academies throughout the USA, Europe and Asia, before triggering further tests, namely an echocardiogram (ultrasound of the heart). However, until now, recommendations for ECG interpretation have not provided consideration to the unique patterns of a paediatric athlete. In view of this, when the doctor is presented with a young athlete, they are often placed in a conundrum on how best to interpret the ECG.
Increased chance of detecting a heart condition
For the first time, we assessed new international recommendations for ECG interpretation in athletes published in Heart, which provide special consideration to the paediatric athlete, in over 1300 (11–18 years-old) male athletes. At presentation, it is important to know how likely it is that a paediatric athlete has a heart condition that may cause him to suffer sudden cardiac death/arrest. Before undertaking any diagnostic test and using a questionnaire, family history and physical examination, we found there is a 1% chance of detecting a heart condition. If we add a simple ECG into the screening process and apply new international recommendations (which provide special consideration to the paediatric athlete) for ECG interpretation, this increases to an 8% chance of detecting a heart condition. Whilst 8% might seem low, in the context that this heart condition could cause the athlete to suffer sudden cardiac death/arrest, we should undertake further tests. Of further value, should new international recommendations inform us that an athletes ECG is normal, indicative that a heart condition is absent, there is now a 0.4% chance of this test being inaccurate.
Can we do better?
A recent 20-year study recently published in the New England Journal of Medicine found a total of six athletes with normal screening as per ECG and echocardiogram, to suffer sudden cardiac death nearly seven years post-initial evaluation. A finding of particular concern for two reasons: firstly, if a paediatric athlete presented with a normal ECG as per new international recommendations for ECG interpretation a 0.4% chance still exits of missing a heart condition that could result in death; and also, a screening is often based on one-off assessments, and thus it is possible to miss a heart condition that may subsequently develop as the athlete matures.
International recommendations for ECG interpretation in athletes provide special consideration to the paediatric athlete, recognising specific juvenile patterns to be normal in the athlete aged less than 16 years. This recommendation offers obvious simplicity in application, but in reality, when presented with two 15 year-olds, we are likely presented with two individuals at very different stages of their pubertal development. When we consider this recommendation assumes an immature heart, it may be appropriate to consider further information. Biological age may be determined by skeletal age assessment, recognised by the international Olympic committee as the ‘gold-standard’ assessment of maturational status however this would require the athlete to undertake a single wrist x-ray.
Cardiac screening by ECG in athletes appears to be justified, in view of the higher than expected incidence of sudden cardiac death and its ability to effectively trigger further evaluation in those at highest risk. However, it is apparent future work should consider alternative means to better determine when the specific juvenile patterns are not indicative of a heart condition in the paediatric athlete.