Table 1

Abnormal ECG criteria in athletes. Any abnormal finding is considered training-unrelated and suggests the possibility of underlying pathological ciac disease, requiring further diagnostic investigation.

Abnormal ECG findingDefinition
T-wave inversion>1 mm in depth from baseline in two or more adjacent leads not including aVR or V1
ST-segment depression≥1 mm in depth in two or more adjacent leads
Pathological Q waves>3 mm in depth or >0.04 s in duration in two or more leads
Complete left bundle branch blockQRS >0.12 s, predominantly negative QRS complex in lead V1 (QS or rS), and upright monophasic R wave in leads I and V6
Complete right bundle branch blockQRS >0.12 s, terminal R wave in lead V1 (rsR') and wide terminal S wave in leads I and V6
Intraventricular conduction delayNon-specific, QRS >0.12 s
Left atrial enlargementProlonged P wave duration of >0.12 s in leads I or II with negative portion of the P wave ≥1 mm in depth and ≥0.04 s in duration in lead V1
Left axis deviation−30° to 90°
Right atrial enlargementHigh/pointed P wave ≥2.5 mm in leads II and III or V1
Right ventricular hypertrophyRight axis deviation ≥120°, tall R wave in V1+persistent precordial S waves (R–V1+S–V5>10.5 mm)
Mobitz type II 2° AV blockIntermittently non-conducted P waves not preceded by PR prolongation and not followed by PR shortening
3° AV blockComplete heart block
Ventricular pre-excitationPR interval <0.12 s with a δ wave (slurred upstroke in the QRS complex)
Long QT intervalQTc ≥0.47 s (99% men)
QTc ≥0.48 s (99% women)
(QTc ≥0.50 s (unequivocal LQTS)
Short QT intervalQTc ≤0.34 s
Brugada-like ECG patternHigh take-off and downsloping ST-segment elevation in V1−V3
Epsilon waveSmall negative deflection just beyond the QRS in V1 or V2
Profound sinus bradycia<30 BPM or sinus pauses ≥3 s
Atrial tachyarrhythmiasSupraventricular tachycia, atrioventricular nodal re-entrant tachycia, atrial fibrillation, atrial flutter
Premature ventricular contractions≥2 per tracing
Ventricular arrhythmiasCouplets, triplets, non-sustained ventricular tachycia
  • AV, atrioventricular; BPM, beats per minute; LQTS, long QT syndrome.