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Updated: Jun 20, 2026

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Published on: April 11, 2025
Wide QRS complex supraventricular tachycardia with negative precordial concordance
Loukas K Pappas1, Michalis Efremidis, Konstantinos P Letsas
1Second Department of Cardiology, Evangelismos General Hospital of Athens, Athens, Greece. lukepappas@hotmail.com
Abstract:
The authors describe the case of a 49-year-old man who experienced an episode of palpitations and dizziness. The results of 24-hour Holter monitoring demonstrated an episode of wide QRS complex regular tachycardia. During the electrophysiological study, a wide QRS complex tachycardia with negative precordial concordance was induced. A diagnosis of orthodromic atrioventricular re-entrant tachycardia involving a left lateral accessory pathway with left bundle branch aberration was made. This case represents a rare exception to the rule that negative precordial QRS concordance is diagnostic of ventricular tachycardia.
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