Electrocardiographic findings in sports medicine: Normal variants and the ones that should not be missed

There are a few “red flag” findings in the history and physical examination of an athlete that may require obtaining an electrocardiogram (ECG) as part of a cardiac evaluation. In this article we discuss the normal variants seen in the ECG brought on by regular physical training and ECG abnormalities that are seen with a few of the structural and conduction abnormalities associated with an increased risk of sudden cardiac death. These conditions are all relatively uncommon and the ECG may reveal the first clue to the presence of a potentially significant underlying abnormality. After reading this article the sports medicine practitioner should be able to 1) confidently return to play those athletes with normal variants on their ECG, and 2) not miss the ECG abnormalities of an athlete who requires further evaluation for potentially significant abnormalities prior to participating in athletics.