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[Premature outflow tract ventricular contraction combined with complete bundle branch block: the characteristic

C Y Di, Z Wan1, K Li

  • 1Centre of Cardiology, Tianjin Medical University General Hospital, Tianjin 300052, China.

Zhonghua Nei Ke Za Zhi
|December 5, 2017
PubMed

Insights

Electrocardiogram (ECG) analysis for premature ventricular contraction (PVC) in patients with complete left/right bundle branch block (CL/RBBB) can be misleading. Mapping and ablation are crucial for accurate PVC origin determination in these cases.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Diagnostics

Background:

  • Bundle branch blocks (BBB) can complicate electrocardiogram (ECG) interpretation.
  • Premature ventricular contractions (PVCs) originating in patients with BBB require careful analysis to determine their source.

Purpose of the Study:

  • To investigate ECG characteristics of PVCs in patients with complete left or right bundle branch block (CL/RBBB).
  • To identify potential ECG features for PVC origin in CL/RBBB patients.
  • To compare ECG findings between patients with and without CL/RBBB.

Main Methods:

  • Retrospective analysis of 8 outflow tract PVC patients with CL/RBBB undergoing radiofrequency ablation.
  • Division of patients into complete right bundle branch block (CRBBB) and complete left bundle branch block (CLBBB) groups.
  • Comparison of ECG characteristics and potential features with a control group without CL/RBBB.

Main Results:

  • Most PVCs showed a precordial R/S>1 transition at lead V4, with exceptions in CRBBB and CLBBB groups.
  • Precordial R/S>1 transition was not delayed compared to sinus rhythm in the CLBBB group.
  • No significant difference in QRS duration between sinus rhythm and PVC in CL/RBBB patients, unlike the control group.

Conclusions:

  • Bundle branch block can lead to misinterpretation of PVC origin on ECG during sinus rhythm.
  • Accurate determination of PVC origin in CL/RBBB patients relies on electrophysiological mapping and ablation results.

Keywords:
Bundle-branch blockElectrocardiogramRadiofrequency catheter ablationVentricular premature

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