Pre-participation Screening ECG Abnormality Score (International Criteria)

Pre-participation Screening ECG Abnormality Score (International Criteria): Explanation and Clinical Context The International Criteria provide a systematic approach to differentiate physiological, training-related ECG changes from patterns suggestive of cardiac pathology in athletes aged roughly 12–35 years. Borderline findings (left/right axis deviation, left/right atrial enlargement, and complete right bundle branch block) are common variants; a single borderline finding in isolation does not require further work-up, but the presence of two or more borderline findings places the ECG into the abnormal category and warrants clinical evaluation. Abnormal findings include (among others) T-wave inversion outside recognized age/ethnicity exceptions, ST-segment depression, pathological Q waves, complete left bundle branch block, ventricular pre-excitation (WPW), Brugada type 1 pattern, epsilon waves/ARVC patterns, significant ventricular ectopy or ventricular arrhythmias on a standard 10-second tracing, atrial tachyarrhythmias, and marked rate or conduction abnormalities (e.g., sinus bradycardia <30 bpm or pauses ≥3 s, PR ≥400 ms, Mobitz II, complete AV block).

QTc prolongation is considered abnormal at ≥470 ms in males and ≥480 ms in females (marked at ≥500 ms). Age and ethnicity modify interpretation of anterior T-wave inversion: TWI confined to V1–V3 in athletes <16 years, and TWI confined to V1–V4 in Black athletes when preceded by convex ST-segment elevation, can be benign adaptations. Lateral or inferolateral TWI in any athlete is abnormal and should prompt evaluation for occult cardiomyopathy.

These rules, when applied consistently, reduce false positives while maintaining sensitivity for conditions linked to sudden cardiac death (e.g., HCM, ARVC, channelopathies).