Table 2.
International ECG criteria: normal and borderline ECG findings in athletes 35 years and younger [12–14]
| Cardiac adaptation | Normal ECG finding | Borderline ECG finding |
|---|---|---|
| Vagotonia | Sinus bradycardia or arrhythmia | |
| Ectopic atrial or junctional rhythm | ||
| 1st degree AV block | ||
| Wenckebach AV block | ||
| Changes of cavity size and wall thickness (cardiac remodelling) | Incomplete RBBB | Complete RBBB |
| Increased QRS voltage for LVH or RVH | Left atrial enlargement | |
| Early repolarisation/ST-segment elevation | Right atrial enlargement | |
| ST-segment elevation followed by T‑wave inversion leads V1-4 in Afro-Caribbean athletes | Left axis deviation | |
| T-wave inversion leads V1-3 age 16 years and younger | Right axis deviation |
AV atrioventricular, ECG electrocardiogram, RBBB right bundle branch block, LVH left ventricular hypertrophy, RVH right ventricular hypertrophy