Atrial pacing bigeminy: a manifestation of crosstalk.

Atrial pacing bigeminy, defined as atrial pacing with alternating short and long cycle lengths, was recorded in two out of five DDD-pacemaker implants. Another fascinating feature, the lowering of the effective pacing rate after programming to a higher rate, occurred in one patient. Both phenomena can be explained by crosstalk; appropriate programming resulted in normal DDD-function in all cases. These observations in our patients have led to some interesting conclusions regarding multiprogrammability and nominal settings.