ECG Challenge
ECG Section Editors
Authors: Víctor Expósito, Susana González-Enríquez, Felipe Rodríguez-Entem
UNCOMMON CAUSE OF SYNCOPE IN WPW SYNDROME CASE PRESENTATION – QUESTION:
A 38-year-old man was referred with transient episodes of syncope over a period of 2 years. Attacks occurred at rest and were non-related to exercise. He denied previous episodes of tachyarrhythmia or palpitations preceding loss of consciousness. He had no relevant past medical history and was not receiving any antiarrhythmic drug. Family history was unremarkable for cardiovascular diseases. An ECG showed intermittent WPW syndrome with right antero-septal pattern. Holter monitoring during an event demonstrated prolonged periods of complete heart block, with no ventricular escape (figure 1).

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