Comparative evaluation of bipolar atrial electrogram amplitude during everyday activities: atrial active fixation versus two types of single pass VDD/R leads

Area of Science:

• Electrophysiology
• Cardiovascular Devices
• Biomedical Engineering

Background:

• P wave amplitude (PWA) is crucial for atrial sensing in pacemakers.
• Limited data exists on PWA stability in single-lead VDD/R pacemakers during daily activities.

Purpose of the Study:

• To investigate PWA variations during daily life activities in patients with DDDR and VDD/R pacemakers.
• To assess the impact of physical activities and maneuvers on PWA and atrial sensing.

Main Methods:

• Telemetry recorded atrial electrograms from 21 DDDR and 29 VDD/R pacemaker patients.
• Analysis of PWA during rest, physical activities (walking), and the Valsalva maneuver (VM).

Main Results:

• Marked individual variability in PWA was observed across activities.
• Significant PWA reduction occurred during walking (Elite II) and VM relaxation phase.
• Atrial sensing failures were noted in 5 patients during VM or walking.

Conclusions:

• Daily activities cause significant PWA variation, dependent on patient, lead type, and maneuver.
• A sensing threshold set at twice the normal PWA may be insufficient for reliable atrial sensing.
• Further research is needed to optimize pacemaker sensing parameters.