[CME ECC 65: The Athlete's ECG]
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Updated: Dec 26, 2025

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Published on: December 19, 2024
Susanne Markendorf1, Christian M Schmied1, Corinna B Brunckhorst1
1Universitätsspital Zürich, Klinik für Kardiologie.
Abstract:
CME ECC 65: The Athlete's ECG Abstract. Regular, intensive training in athletes causes a modulation of the heart due to higher vagal tone and emerging hypertrophy. To assess these changes, which can be seen in an athlete's ECG as well, an international group of experts constituted contemporary standards for ECG interpretation in athletes, the "Seattle Criteria" which are discussed in this article: Athletes often have a physiologic sinus bradycardia with a heart rate between 30 and 60 bpm and a pronounced respiratory arrhythmia. A junctional rhythm with retrograde depolarisation of the atria frequently occurs as well, especially at rest. Early repolarisation is also an occasional phenomenon in athletes. Depending on its morphology and the history of the athlete it may be regarded as physiologic. This article shall help to evaluate an athlete's ECG in a physician's routine.
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