The earliest published electrocardiogram showing ventricular preexcitation.

When in 1930, Wolff, Parkinson, and White published what is today known as the WPW, or preexcitation syndrome, they, and subsequently others, found few comparable cases in the preceding literature. Among these the report of Cohn and Fraser, published in 1913, was the earliest. However, another even earlier documentation in a 1909 article by Hoffmann escaped notice till now. The ECG of a patient with paroxysmal tachycardia reveals a short PR interval and a delta-wave-induced widening of the QRS complex, even though the reproduced tachycardia was not preexcitation related. The interpretation of this poorly reproduced ECG can be confirmed by another and more detailed description of the patient in an electrocardiography textbook published in 1914 by the same author. Thus, the earliest publication of an ECG showing ventricular preexcitation now can be dated back to 1909. Moreover, the Hoffmann monograph contains two additional examples of the WPW syndrome not noticed until now. All three cases published by Hoffmann had their first ECG recordings in 1912 or earlier.