Efficiency of a pacemaker clinic to prevent sudden pacing failures.

Two hundredpatients with implantedpacemakers werefollowed in a pacemaker clinic over a period of 3years. The follow-up times ranged from I to 36 months, with a mean of 22 months. The material represents 366 patient-years ofpacing and 361 pacemakers. One hundred and twenty replacements were done. Most of these were elective (93%) and based on gradual deterioration of the pacing detected by photoanalysis of the gener- ator impulse. Of the single variables the duration of the impulse and the discharge rate were most revealing; recording changes in these two variables led to 96 per cent failure detection. There were 28 deaths within the follow-up time: 3 of them were related to pacing failure and 5 were possibly so. When these sudden fatal events were added to the sudden nonfatal failures not detected by the routine control system a I6 per cent failure rate of detection emerged. The total annual mortality was 7.7 per cent. The mortality caused by pacing failures was 2 2 per cent per annum.