ECGs in Athletes

Criteria for a positive 12-lead ECG
P wave
left atrial enlargement: negative portion of the P wave in lead V1 � 0.1 mV in depth and �0.04 s in duration right atrial enlargement: peaked P wave in leads II and III or V1 � 0.25 mV in amplitude
QRS complex
frontal plane axis deviation: right ≥ +120° or left –30° to –90°; increased voltage: amplitude of R or S wave in in a standard lead ≥2 mV, S wave in lead V1 or V2 ≥ 3 mV, or R wave in lead V5 or V6 ≥ 3 mV; 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 leads; right or left bundle branch block with QRS duration ≥ 0.12 s; R or R' wave in lead V1 ≥ 0.5 mV in amplitude and R/S ratio ≥ 1.
ST-segment, T-waves, and QT interval
ST-segment depression or T-wave flattening or inversion in two or more leads; prolongation of heart rate corrected QT interval (QTc) > 0.44 s in males and > 0.46 s in females.
Rhythm and conduction abnormalities
premature ventricular beats or more severe ventricular arrhythmias; supraventricular tachycardias, atrial flutter, or atrial fibrillation; short PR interval (< 0.12 s) with or without ‘delta’ wave; sinus bradycardia with resting heart rate ≤ 40 beats/mina;^a first (PR ≥ 0.21 s^b), second or third degree atrioventricular block.
^{a/sup>Increasing less than 100 beats/min during limited exercise test. ^bNot shortening with hyperventilation or limited exercise test.}

References

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