Table 2

Criteria for a positive 12-lead ECG in the present study according to the 2005 European Society of Cardiology guidelines17

CriterionNoCases in present study (% overall)Percentage of positive ECGs
P wave
    Negative portion of the P wave in lead V1 ⩾0.1 mV in depth and ⩾0.04 s in duration000
    Peaked P wave in leads II and III or V1⩾0.25 mV in amplitude000
QRS complex
    Frontal plane axis deviation: right ⩾+120° or left −30° to −90°000
    Increased voltage: amplitude of R or S wave in a standard lead ⩾2 mV, S wave in lead V1 or V2⩾3 mV, or R wave in lead V5 or V6⩾3 mV0*00
    Abnormal Q waves ⩾0.04 s in duration or ⩾25% of the height of the ensuing R wave or QS pattern in two or more leads21.35
    Right or left bundle branch block with QRS duration ⩾0.12 s42.610
    R or R′ wave in lead V1⩾0.5 mV in amplitude and R/S ratio ⩾1000
ST-segment, T-wave, QT interval
    ST-segment depression or T-wave flattening or inversion in two or more leads312077.5
    Prolongation of heart rate corrected QT interval >0.44 s in males and>0.46 s in females000
Rhythm and conduction abnormalities
    Premature ventricular beats or more severe ventricular arrhythmias000
    Supraventricular tachycardias, atrial flutter or atrial fibrillation000
    Short PR interval (<0.12 s) with or without “delta” wave31.97.5
    Sinus bradycardia with resting heart rate ⩽40 beats/min (only if increasing less than 100/min in stress test)000
    First-degree (PR⩾0.21 s) AV block (only if not shortening through hyperventilation or exercise test)000
    Second- or third-degree AV block000
  • Only the leading ECG finding is listed when a player had more than one positive finding.

  • *No athlete had the exclusive finding of increased ECG voltage. Voltage changes considered to be significant were always associated with another leading ECG finding.