Related Experiment Video
Updated: May 21, 2026
12:45
Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Unusual cause of desynchronization in a cardiac resynchronization device
S S Barold1, M Steiner, A Kucher
1Florida Heart Rhythm Institute, Tampa General Circle, 33606, Tampa, FL, USA. ssbarold@aol.com
Herzschrittmachertherapie & Elektrophysiologie
|June 5, 2012
Summary
A new cause of cardiac resynchronization device desynchronization is identified. Programming the left ventricular (LV) maximum trigger rate correctly prevents stimulation inhibition during sensor-driven pacing.
Area of Science:
- Cardiology
- Biomedical Engineering
- Medical Device Technology
Background:
- Cardiac resynchronization therapy (CRT) devices improve heart function in eligible patients.
- VVIR mode pacing uses sensor input to adjust heart rate.
- Left ventricular (LV) stimulation is a key component of CRT.
Observation:
- Desynchronization occurred in a CRT device operating in VVIR mode.
- LV stimulation was unexpectedly inhibited.
- Inhibition happened when the sensor-driven heart rate surpassed the programmed LV maximum trigger rate.
Findings:
- A novel cause of CRT desynchronization was identified.
- The desynchronization resulted from an improperly programmed LV maximum trigger interval.
- The LV maximum trigger interval must be set to a rate equal to or faster than the sensor-driven upper rate.
Implications:
- Correct programming of the LV maximum trigger interval is crucial for effective CRT.
- Physicians must be aware of this potential desynchronization issue.
- Ensuring appropriate device settings can optimize patient outcomes and prevent adverse events.
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