[Modification of stimulus threshold increase following heart pacemaker implantation by prednisolone]

In a retrospective study concerning 39 patients with pacemakers is reported on the possibility of a medicamentous influence of so-called increases of the stimulus threshold with exit block. Inflammatory tissue reactions and disturbances of electrolytes as well as microdislocations at the tip of the electrode are given as a cause of the postoperatively appearing deficiency of the stimulation. A differentiation of these causes is not possible with simple paraclinical examination methods. Generally using prednisolone we succeeded in decreasing the stimulus threshold in about half the patients within ca. 3 weeks and thus in removing the exit block. After discussion of the pathophysiological connections recommendations for the therapeutic approach are described.