T-wave changes of cardiac memory caused by frequent premature ventricular contractions originating from the right ventricular outflow tract

J Cardiovasc Electrophysiol. 2019 Sep;30(9):1549-1556. doi: 10.1111/jce.14008. Epub 2019 Jun 25.

Abstract

Introduction: Cardiac memory is recognized as altered T-waves when the sinus rhythm resumes after an abnormal myocardial activation period that recovers slowly over several weeks. The T-wave changes after ablation of frequent premature ventricular contractions (PVCs) as cardiac memory was not known.

Objective: This study identified whether cardiac memory exists after successful ablation of PVCs from the right ventricular outflow tract (RVOT).

Methods: We investigated 45 patients who underwent successful ablation of PVCs from RVOT and 10 patients who underwent unsuccessful ablation. We analyzed the amplitude of the T-wave, QT intervals, and QRST time-integral values of a 12-lead electrocardiogram before ablation and 1 day, 3 days, and 1 month after ablation.

Results: In the successful ablation group, the amplitude of the T-wave and QRST time-integral values of lead II, III, aVR, aVL, and aVF significantly changed after ablation and gradually normalized within 1 month. In addition, if the number of pre-ablation PVCs was small, then the corresponding impact was also small. However, the greater the number of pre-ablation PVCs, the more prominent the changes. Significant changes were not observed in the unsuccessful ablation group.

Conclusion: When ablation of PVCs from RVOT was successful, primary T-wave changes because of cardiac memory and the gradual normalization of the amplitude of the T-wave were observed. No significant T-wave changes were detected after unsuccessful ablation.

Keywords: T-wave change; ablation; cardiac memory; outflow tract; premature ventricular contraction.

Publication types

  • Comparative Study
  • Observational Study

MeSH terms

  • Action Potentials*
  • Adolescent
  • Adult
  • Aged
  • Catheter Ablation* / adverse effects
  • Child
  • Child, Preschool
  • Electrocardiography
  • Female
  • Heart Conduction System / physiopathology
  • Heart Conduction System / surgery*
  • Heart Rate*
  • Humans
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Recurrence
  • Retrospective Studies
  • Risk Factors
  • Time Factors
  • Treatment Failure
  • Ventricular Premature Complexes / diagnosis
  • Ventricular Premature Complexes / physiopathology
  • Ventricular Premature Complexes / surgery*
  • Young Adult