Pulse amplitude adjustment provides immediate pacemaker longevity gain.
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).


CONCLUSIONS
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.
Zlatanovic
Nenad
N
Institute for Heart Diseases, University Clinical Center, Skopje, Republic of Macedonia. zlic2009@ukim.edu.mk
Kedev
Sasko
S
Gjorgov
Nikola
N
Miletic
Branislav
B
Georgiev
Antonio
A
Kovacevic
Dejan
D
Trajkov
Ivan
I
Kaev
Mitko
M
Borozanov
Vladimir
V
Boskov
Vladimir
V
D000368:Aged; D001919:Bradycardia / Q000628:therapy*; D002304:Cardiac Pacing, Artificial; D004567:Electrodes, Implanted; D004867:Equipment Design; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010138:Pacemaker, Artificial