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

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.

Electrophysiological ventricular substrate of stroke: a prospective cohort study in the Atherosclerosis Risk in Communities (ARIC) study

“…It is well known that PVCs can induce cardiac memory, which is manifested by a wide QRS-T angle 56 57 and a large QRST integral. 58 In this study, the response of the specific electrophysiological ventricular substrate measures (PVCs, spatial QRS-T angle and SAIQRST) on stepwise adjustment (models 1–4, figure 2 ) was similar, supporting the notion that spatial QRS-T angle and SAIQRST reflect cardiac memory. We also observed a gradual, ‘dose-dependent’ association of QRS-T angle and SAIQRST with the hazard of cardio-ES ( figure 3A ).…”

Does Ventricular Substrate Play a Role in Incident Stroke? The Atherosclerosis Risk in Communities (ARIC) Study

“…It is well-known that PVCs can induce cardiac memory, which is manifested by a wide QRS-T angle 57, 58 , and a large QRST integral. 59 In this study, the response of the specific ventricular substrate measures (PVCs, spatial QRS-T angle, and SAI QRST) on stepwise adjustment (models 1-4, Figure 2) was similar, supporting the notion that spatial QRS-T angle and SAI QRST reflect cardiac memory. We also observed a gradual, “dose-dependent” association of QRS-T angle and SAI QRST with the hazard of cardioembolic stroke (Figure 3).…”

Editorial: Cardiac or T wave memory after radiofrequency ablation of right ventricular outflow tract ectopics

“…In those with <5000, the only change was in the amplitude of the T wave in lead 3. Significant changes were not observed in the unsuccessful group . These findings proved that the T wave changes were related to ablation of ectopics and not due to the myocardial damage related to the delivery of RF energy.…”

“…T wave memory after ablation of RVOT ectopics by Sakomoto et al is a worthy addition to the literature on this subject.…”

“…In this issue of Journal of Cardiovascular Electrophysiology , Sakomoto et al describe T wave changes of cardiac memory following radiofrequency (RF) ablation of frequent premature ventricular contractions (PVCs) originating from the right ventricular outflow tract (RVOT). They compared 45 patients who underwent successful ablation defined as <1% PVCs 1 month after ablation, with 10 patients who had unsuccessful ablation.…”