As early as 1845, J.E. Purkinje described the Purkinje fibres named after him and in 1893 W. His jr. described the His bundle. In 1906 L. Aschoff and S. Tawara described the AV knot for the first time.
One year later, the sinus node was discovered as the primary center of stimulation by A. Keith and M. W. Flack. The Wenckebach bundle was described in 1906 / 1907 by K. F. Wenckebach and the Mahaim fibers by I. Mahaim in 1932 (Lewalter 2010).