Epicardial electrodes implanted in 20 patients between 1959 and 1962 had a short-term
effectiveness. A change to endocardial stimulation was later necessary in 15 of these
patients. Endocardial electrodes inserted between 1962 and 1967 in 306 patients were
included in this study; 121 (40 %) of these patients survived for 10 years or more.
Seventy-five (62 %) of the long-term survivors had no problems with their electrodes.
In 39 of these patients the stimulation thresholds were measured after both 5 and
10 years and found to be 2.3 ± 0.6 volts and 2.2 ± 0.8 volts, respectively. Hence,
long-term complication-free endocardial pacing can be accomplished.
Cardiac pacing electrodes
