Interruption of cardiac resynchronization therapy by atrial premature complexes
S Serge Barold1, Andreas Kucher2
1Department of Medicine, University of Rochester, School of Medicine and Dentistry, Rochester, NY, United States.
Journal of Electrocardiology
|November 23, 2017
Summary
Cardiac resynchronization therapy (CRT) with defibrillation (CRT-D) devices can experience pacing interruptions. Atrial premature complexes can trigger left ventricular sensing, inhibiting pacing and causing desynchronization.
Area of Science:
- Cardiology
- Biomedical Engineering
- Electrophysiology
Background:
- Biotronik's third-generation CRT-D devices (i-family) feature left ventricular (LV) sensing capabilities.
- LV sensing, while beneficial, can under specific conditions lead to loss of cardiac resynchronization therapy (CRT).
- These devices can record electrograms during "CRT pacing interrupt" episodes.
Observation:
- Three cases of sudden "CRT pacing interrupt" were observed, initiated by atrial premature complexes (APCs).
- APCs caused a realignment of LV timing cycles, leading to inhibition of LV pacing.
- This inhibition initiated a self-perpetuating desynchronization process.
Findings:
- Repeated LV sensed events prevented LV pacing by displacing the LV upper rate interval.
- The observed desynchronization was triggered by APCs interacting with the device's LV sensing algorithm.
- The i-family CRT-D's ability to record event-triggered tracings was crucial in identifying this phenomenon.
Implications:
- Understanding this mechanism is vital for managing patients with CRT-D devices.
- Programming an LV upper rate faster than the maximum sensor-driven rate or right ventricular upper rate can prevent desynchronization.
- This highlights the importance of device programming in maintaining effective CRT.
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