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Updated: Jun 5, 2026
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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
Interatrial conduction correlates with optimal atrioventricular timing in cardiac resynchronization therapy devices
Vadim Levin1, Mehdi Razavi, Robert Coll
1Lehigh Valley Hospital, Allentown, Pennsylvania, USA.
Pacing and Clinical Electrophysiology : PACE
|January 7, 2011
Summary
Interatrial conduction time (IACT) is key for optimizing atrioventricular delay (AV) in cardiac resynchronization therapy (CRT). Heart rate adjustments to AV may not benefit CRT patients during atrial pacing.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Optimizing atrioventricular delay (AV) can improve cardiac resynchronization therapy (CRT) outcomes.
- Optimal AV correlates with interatrial conduction time (IACT) during right atrial pacing.
- This study validates this correlation across varying heart rates and during sinus rhythm.
Purpose of the Study:
- To prospectively validate the correlation between IACT and optimal AV.
- To examine this correlation during sinus rhythm and atrial pacing at different rates.
- To assess the impact of heart rate on AV optimization in CRT patients.
Main Methods:
- Electrophysiology catheters used in 33 CRT implant patients.
- IACT measured via coronary sinus electrograms during sinus rhythm and atrial pacing.
- Echocardiographic optimization of AV delay using mitral inflow method post-implant.
Main Results:
- Optimal sensed and paced AVs correlated significantly with IACT during sinus rhythm (R=0.76) and pacing (R=0.75).
- Moderate correlations observed between optimal AV, P-wave duration, and RA-RV intervals.
- Electrical intervals increased with higher atrial pacing rates.
Conclusions:
- IACT is a critical factor for optimal AV programming in CRT.
- Rate-dependent AV shortening may be inappropriate for CRT patients during atrial pacing.
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