[Unusual manifestations of dual atrioventricular nodal conduction]

In three case reports the unusual patterns of dual atrioventricular nodal conduction are shown - intermittent complete block in the fast pathway, Wenckebach-type block in the fast pathway, and parallel simultaneous conduction through both the nodal pathways with a double ventricular response. The importance of these phenomena consists at least in the differential diagnostics.