Resuscitation great. Karel Wenckebach: the story behind the block.

The first documentation of a human atrioventricular (AV) block dates back to 1873, when A.L. Galabin reported a 34-year-old patient using an apexcardiogram. This was followed the same year by Luciani, recording 2nd degree AV blocks while studying frogs. In 1899, Karel F. Wenckebach provided the cardiology field with the criteria of what he called "Luciani periods", what we now know as Wenckebach Periodicity or Mobitz I AV block. The classic electrocardiographic presentation of Mobitz I/Wenckebach periodicity is characterized by progressive prolongation of the PR interval on the electrocardiogram (EKG) on consecutive beats followed by a blocked P wave. This clinical entity is the first and most common of two types of 2nd degree AV block. This manuscript reviews the life of Karel F. Wenckebach and the events that led this great Dutch physician to make one of the most important contributions to the field of cardiology.