RESUMO
UNLABELLED: Proper functioning of a pacemaker depends exclusively on the detection of intrinsic cardiac signals. Conventional devices merely establish the presence of an endocavitary potential, but do not evaluate it qualitatively. The recent incorporation of digital signal processing of sensed events in pacemaker permits diagnostic characterization heretofore impossible. METHODS: Digital processing was used in 268 cardiac cycles recorded from 5 patients during elective dual chamber pacemaker replacement, The signals were classified in real time by an external pacemaker equipped with hardware and software capabilities for this purpose. RESULTS: The parameters used for morphological analysis were the minimum value of the slope signal and the minimum value of the filtered signal. The discrimination of a true atrial signal from a far-field R wave was correct in every patient (p < 0.0001). CONCLUSION: Digital devices may monitor and classify every event continually, and dramatically increase device reliability and the amount of information that can be processed and stored.