The characteristics of a 12-lead electrocardiogram measuring premature ventricular contractions originating from the tricuspid annulus using the clock position method.

OBJECTIVE: This study aimed to analyze the conventional surface electrocardiogram (ECG) characteristics of premature ventricular contractions (PVCs) originating from the tricuspid annulus and to investigate the efficacy of locating their origins according to ECG results. METHODS: Eight patients who underwent radiofrequency ablation in the First Hospital of Shanxi Medical University (China) were included in the study. Pace mapping (PM) was used to analyze the characteristics of the PVCs originating from the tricuspid annulus recorded via 12-lead body surface ECGs. RESULTS: An R-wave was found in leads I, V5 , and V6 . The QRS wave was narrower when the PVCs originated from the septum and shifted in lead V3 (R-wave amplitude/S-wave amplitude in the precordial lead-1). The QRS wave was broadest when the PVCs originated from the 7 to 9 o'clock position. The augmented vector left lead showed RS, QS, or RSR-type waves with a low amplitude when the PVCs originated from the upper part of the annulus. When the PVCs originated from the lower part of the annulus, the augmented vector right lead reflected multidirectional and QS-type waves. CONCLUSION: The ECG-lead characteristics related to the origin of PVCs in the tricuspid annulus indicate some level of significance and can be used to formulate a specific diagnosis.