Risk of VF Undersensing in Extra-Vascular ICD Due to Concomitant Leadless Pacing

Area of Science:

• Cardiology
• Biomedical Engineering
• Electrophysiology

Background:

• Extravascular implantable cardioverter-defibrillators (EV-ICDs) offer advanced cardiac rhythm management but have limited pacing capabilities.
• Patients with EV-ICDs may require additional pacing support, potentially from leadless pacemakers such as Micra.
• Concomitant use of EV-ICDs and leadless pacemakers raises concerns about potential device interference.

Purpose of the Study:

• To investigate the potential interference between Micra pacemaker pacing pulses and EV-ICD arrhythmia detection algorithms.
• To determine the impact of pacing amplitudes and pulse widths on the EV-ICD's ability to accurately detect ventricular fibrillation (VF).

Main Methods:

• Analysis of a ventricular fibrillation (VF) database to simulate interference scenarios.
• Evaluation of the effect of varying pacing amplitudes and pulse widths on EV-ICD detection of VF.
• Identification of critical thresholds for pacing parameters that could affect VF detection accuracy.

Main Results:

• EV-ICD's detection of VF is not confounded by pacing pulses with amplitudes up to approximately 0.99±0.56 mV (1.3 times VF amplitude).
• Pacing pulse widths exceeding 0.24 ms significantly impair the EV-ICD's ability to detect VF.
• Specific pacing parameter thresholds were identified that could impact device performance.

Conclusions:

• Optimizing pacing parameter configuration is crucial for the safe and effective combined use of EV-ICDs and leadless pacemakers.
• Careful selection of pacing amplitudes and pulse widths can prevent interference with EV-ICD arrhythmia detection.
• This research provides essential data for establishing guidelines for dual-device therapy in cardiac rhythm management.