“Wenckebach phenomenon”, a form of arrhythmia.

This monograph contains Wenckebach's obserations on the physiological bases of arrhythmias, along with accounts of their clinical manifestations. Wenckbach was the first to describe extracystoles in man, demonstrating independently of Cushny (1906) that these ineffectual contractions were premature beats. His name is commemorated in the expression "Wenckebachs periods," denoting periodic dropped beats when a conduction defect exists.

Wenckebach was the first to demonstrate (pp. 173-75) the value of quinine (“Wenckebach’s pills”) in the treatment of paroxysmal fibrillation. The same work contains a number of excellent descriptions of various forms of cardiac arrythmia. The second edition, written in co-operation with Heinrich Winterberg, was expanded to 2 vols, Leipzig, Engelmann, 1927.

Wenckebach wrote a classic account of the heart in beriberi.