Interactions between a rapid atrial stimulator and a multiprogrammable ventricular demand pacemaker

A patient with drug-resistant supraventricular tachycardia was well controlled for 8 years with a patient-activated rapid atrial pacemaker until she developed symptomatic bradycardic episodes. A multiprogrammable ventricular pacemaker was implanted. Assessment of the interactions between the two pacemakers demonstrated inhibition of VVI pacing by the atrial stimulator initially. Two months after implant no interaction was seen. At no time was VVT pacing affected by the atrial stimulator. Thus, interactions between these two units can occur and a multiprogrammable pacemaker should be used in this situation as it offers the flexibility to minimize any interaction that might be present.