ECGs in Athletes

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.

Criteria for a positive 12-lead ECG

QRS complex
frontal plane axis deviation: right �þ1208 or left –308 to –908;	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 R0 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 .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;	first (PR 0.21 s), second or third degree atrioventricular block.
Increasing less than 100 beats/min during limited exercise test.	Not shortening with hyperventilation or limited exercise test.

References

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