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Updated: Jul 11, 2026
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
Efficiency, reproducibility and agreement of five different hemodynamic measures for optimization of cardiac
Zachary I Whinnett1, Justin E R Davies, Gemma Nott
1International Centre for Circulatory Health, St Mary's Hospital and Imperial College, 59-61 North Wharf Road, W2 1LA, London, United Kingdom.
Insights
Optimizing cardiac resynchronization therapy (CRT) AV delay using systolic blood pressure (SBP) offers the best efficiency and reproducibility. Pulse pressure (PP) and mean arterial pressure (MAP) are viable alternatives for CRT optimization.
Area of Science:
- Cardiology
- Biomedical Engineering
- Medical Devices
Background:
- Cardiac resynchronization therapy (CRT) optimization involves adjusting the atrioventricular (AV) delay.
- Hemodynamic measures like pulse pressure (PP), systolic blood pressure (SBP), and cardiac output (CO) are used for AV delay optimization.
Purpose of the Study:
- To determine if different hemodynamic measures identify the same optimal AV delay for CRT.
- To compare the efficiency and reproducibility of PP, SBP, and CO in identifying the optimal AV delay.
Main Methods:
- Twenty-two patients with CRT underwent AV delay adjustments during atrial pacing.
- Systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), mean arterial pressure (MAP), and cardiac output (CO) were recorded.
- Signal-to-noise ratios and correlation coefficients were used to assess efficiency and reproducibility.
Main Results:
- SBP, PP, and CO demonstrated similar signal-to-noise ratios, indicating comparable efficiency.
- Optimal AV delays identified by SBP, PP, MAP, and DBP were highly correlated.
- Cardiac output (CO) showed poor correlation with other measures for optimal AV delay identification.
- Reproducibility was highest for SBP, followed by MAP and PP.
Conclusions:
- The optimal AV delay for CRT is consistently identified using SBP, PP, MAP, or DBP.
- Optimizing CRT AV delay with SBP provides the best balance of efficiency and reproducibility.
- PP and MAP serve as effective alternative parameters for CRT AV delay optimization.
Background:
Several hemodynamic measures have been used for optimization of the AV delay of cardiac resynchronization therapy (CRT), including pulse pressure (PP), systolic blood pressure (SBP) and cardiac output (CO). We aimed to determine whether these measures identify the same optimum and whether they have the same efficiency and reproducibility at identifying this optimum.
Methods And Results:
In 22 patients with cardiac resynchronization therapy, we adjusted the AV delay while atrially pacing at 110 bpm and simultaneously recording SBP, diastolic blood pressure (DBP), PP, mean arterial pressure (MAP) and CO. SBP, PP and CO all had essentially the same signal-to-noise ratios (15.4+/-5.4, 15.5+/-6.4, 15.3+/-7.4 respectively p=NS). In contrast, MAP and DBP had significantly worse signal-to-noise ratios than SBP (14.2+/-5.6, p=0.003 and 12.1+/-4.4, p<0.0001 respectively). The optimal AV delay was very similar between SBP, PP, MAP and DBP. For example, the optima identified by SBP correlated strongly with those identified by PP (r=0.94), MAP (r=0.96) and DBP (r=0.90). In contrast, the optima detected by CO was poorly related to these (e.g. r=0.36 with SBP optima). Reproducibility was best for optima detected by SBP followed by MAP and PP.
Conclusions:
Essentially the same AV optimum is identified, regardless of whether the parameter chosen for maximization is SBP, PP, MAP or DBP. We conclude that optimizing the CRT AV delay using SBP gives the best combination of efficiency and reproducibility, with PP and MAP being reasonable alternatives.
