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Updated: Jun 3, 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
Comparison of hemodynamic versus dyssynchrony assessment for interventricular delay optimization with
Adelina Doltra1, Bàrbara Vidal, Etelvino Silva
1Thorax Clinic Institute, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain.
Background:
Best practice for cardiac resynchronization therapy (CRT) device optimization is not established. This study compared Tissue Doppler Imaging (TDI) to study left ventricular (LV) synchrony and left ventricular outflow tract velocity-time integral (LVOT VTI) to assess hemodynamic performance.
Methods:
LVOT VTI and LV synchrony were tested in 50 patients at three interventricular (VV) delays (LV preactivation at -30 ms, simultaneous biventricular pacing, and right ventricular preactivation at +30 ms), selecting the highest VTI and the greatest degree of superposition of the displacement curves, respectively, as the optimum VV delay.
Results:
In 39 patients (81%), both techniques agreed (Kappa = 0.65, p < 0.0001) on the optimum VV delay. LV preactivation (VV - 30) was the interval most frequently chosen.
Conclusions:
Both TDI and LVOT VTI are useful CRT programming methods for VV optimization. The best hemodynamic response correlates with the best synchrony. In most patients, the optimum VV interval is LV preactivation.
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