Wolff-Parkinson-White Alternans (WPW Alternans) ECG

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ECG Findings:

1. Sinus Tachycardia

2. Wolff-Parkinson-White Syndrome with Alternans

When every other beat conducts through an accessory pathway causing a short PR interval and a delta wave, the term WPW alternans is used. The accessory pathway that is exists is refractory on an alternating basis creating this appearance. This is a relatively rare ECG finding.