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The effect of exercise on the atrial electrogram voltage in young patients
B A Ross1, V Zeigler, A Zinner
1Department of Pediatrics, Children's Hospital of King's Daughters, Eastern Virginia Medical School, Norfolk 23507.
Pacing and Clinical Electrophysiology : PACE
|December 1, 1991
Summary
Vigorous exercise significantly reduces atrial electrogram size in patients with pacemakers. This decrease, averaging 33.8%, highlights the need for flexible atrial sensing settings in active individuals.
Area of Science:
- Cardiology
- Biomedical Engineering
- Electrophysiology
Background:
- Atrial electrogram sensing is crucial for dual-chamber pacing systems, especially in active individuals.
- Understanding exercise-induced changes in atrial electrogram size is vital for optimizing pacemaker function.
Purpose of the Study:
- To investigate the impact of vigorous exercise on atrial electrogram amplitude in pediatric and young adult patients.
- To determine if lead fixation type influences exercise-induced changes in atrial electrogram size.
Main Methods:
- Eleven children and young adults with bipolar dual-chamber pacemakers underwent treadmill exercise testing.
- Atrial electrogram size was measured at rest and during exercise using telemetric data.
- Lead fixation types (tined/passive vs. screw-in/active) were analyzed for differences.
Main Results:
- Atrial electrogram size decreased significantly with exercise, from a mean of 5.08 mV to 3.44 mV (P = 0.002).
- This represented a mean reduction of 33.8% (P < 0.001), with no significant difference between lead types.
- Exercise-induced decrease in atrial electrogram size was observed across all participants.
Conclusions:
- Vigorous exercise leads to a substantial decrease in atrial electrogram size.
- This finding suggests that atrial sensitivity settings may need adjustment in active patients.
- Maximal atrial electrograms should be obtained at implant, and flexible pacing systems are recommended for athletes.
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