Objective: Adjusting pacemaker pulse amplitude influences the longevity of the pacemaker. Our aim was to establish the initial longevity gain.
Methods: Forty randomly selected patients with implanted pacemakers were analyzed. Mean age was 65.58+/-13.7 years. All pacemakers were working on factory settings of pulse amplitude 3.5 V and pulse width of 0.4 ms for average of 3 years before the adjustment. Initial mean longevity was projected to 68.61+/-18.86 months, mean battery voltage 2.78 V, and mean battery current 14.21+/-2.61 microA.
Results: Pulse amplitude threshold test was performed and average value of 0.632+/-0.22 V was obtained. Pulse amplitude was programmed to 2.5 V and pulse width was left unchanged. New readings of battery data were obtained. Battery voltage did not show immediate changes, and battery current decreased to 11.53+/-1.98 microA. New average longevity was projected to 81.03+/-19.82 months, which presents a 12.42 months of initial longevity gain with statistical significance at 95% confidence interval (p=0.003). Positive correlation was found between the new pulse amplitude and new values of battery current (p<0.01).
Conclusion: Pulse amplitude decrease of only 1 V provides significant initial longevity gain of more than a year. If found correlations would have any impact on further longevity gains over longer period of time is yet to be established.