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Updated: Aug 9, 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
[Tissue Doppler imaging evaluate the effect of optimal biventricular resynchronization for congestive heart disease
Qian Yang1, Jian-an Wang, Liang Dong
1Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University Medical College, Hangzhou 310016, China.
Objective:
To evaluate the immediate change of left ventricular systolic performance and asynchronization between simultaneous biventricular pacing and sequential biventricular pacing by tissue synchronization imaging (TSI) and tissue velocity imaging (TVI) in patients with congestive heart failure. The effect of sequential biventricular resynchronization therapy was also observed.
Methods:
Ten patients with dilated cardiomyopathy who received sequential biventricular resynchronization were enrolled. The TVI and TSI imagings were performed by GE vivid7 with M3S probe. The left ventricular ejection fraction (LVEF), stroke volume (SV), aortic velocity time integral (VTI), left ventricular end diastolic diameter (LVEDd), the standard deviation of the electro-mechanical delay (EMD-SD) of 6 segments and TSI index were measured before implanting of InSync 8042 and 1 month, 3 months, 6 months after implanting respectively.
Results:
After 6 months of implanting, the LVEF, SV and VTI were obviously increased from (22.0 +/- 8.8)% to (38.0 +/- 9.9)%; (36.0 +/- 14.9) ml to (57.0 +/- 15.7) ml; (20.22 +/- 5.72) cm to (26.20 +/- 5.98) cm, P < 0.05, respectively, compared with the before of implanting. The LVEDd was decreased from (6.6 +/- 0.6) cm, to (6.0 +/- 0.9) cm, P < 0.05. The EMD-SD and TSI-index were declined gradually after implanting, which was more evident in the 6 months after implanting, from (83.07 +/- 46.99) ms to (22.37 +/- 16.38) ms; (2.20 +/- 0.36) to (1.50 +/- 0.43), P < 0.05, respectively, but the immediate EMD-SD did not change obviously between simultaneous biventricular pacing and sequential biventricular pacing, whereas, the TSI index and VTI were significantly improved from (1.87 +/- 0.31) to (1.71 +/- 0.29); (22.44 +/- 5.43) cm to (25.44 +/- 5.36) cm, P < 0.05, respectively, in the sequential biventricular pacing.
Conclusion:
Sequential biventricular resynchronization could improve the left ventricular systolic function and synchronism of wall motion in the patients with congestive heart failure, which is more effective than simultaneous biventricular pacing after implanting immediately.
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