ECG Quiz 4

This ECG is suggestive of:

a) Wenckebach phenomenon
b) Ashman phenomenon
c) Katz-Wachtel phenomenon
d) None of the above

Answer: c) Katz-Wachtel phenomenon.

The Katz-Wachtel sign is tall diphasic RS complexes at least 50 mm in height in lead V2, V3 or V4 – mid precordial leads [Circulation 1963;27;1118-1127 (Free full text at:; original description by Katz and Wachtel was published in 1937: Katz LN and Wachtel H. The diphasic QRS type of electrocardiogram in congenital heart disease. Am Heart J; 1937, 13: 202-206]. The sign has been described in ventricular septal defect with biventricular hypertrophy in children. It can be seen with isolated ventricular septal defect as well as complex ventricular septal defect. In fact the Circulation article cited is on Complete Transposition of the Great Vessels: II. An Electrocardiographic Analysis by Larry P et al.