How often are lead impedances measured in pacing devices?

Lead impedances in pacing devices are typically measured every 3 hours. This regular interval allows for timely detection of any significant changes in the lead's electrical characteristics, which can indicate issues such as lead dislodgement, insulation failure, or other potential problems that may affect the device's performance. Monitoring impedances at this frequency ensures that any anomalies can be addressed promptly, which is essential for patient safety and device functionality.

The other options suggest intervals that are either too frequent or too infrequent for practical monitoring purposes. Measuring every hour might lead to excessive data without providing additional clinical benefit, while daily or weekly checks could delay the recognition of critical changes that need immediate attention. Therefore, the three-hour interval strikes a balance between vigilant monitoring and practical management.