AIM  To analyze clinical and electrophysiological characteristics of outflow tract ventricular arrhythmias (OTVA) in patients who have undertaken catheterablation. To evaluate superiority in the origin of OTVA with known clectrocardiogram (ECG) indexes such as the transitional zone (TZ) index, S-wave amplitude in lead V2 divided by R-wave amplitude in lead V3 (V2S/V3R), and R-wave durationindex and R/S-wave amplitude index. To provide a basis for clinical diagnosis and treatment.

  METHODS  Retrospective analysis was performed on the data of 54 inpatients admitted to the general hospital of Ningxia Medical University who had undertaken catheter ablation on January 1, 2011, to December 31, 2017 and who were confirmed to be OTVA by electrophysiology in the operation center. The preoperative 12-lead surface ECG of these patients. R-waveduration index, R/S-wave amplitude index, V2S/V3R index, and TZindex were observed, measured and calculated. The sensitivity, specificity, positive predictive value and negative predictive value, accuracy of ECG for preoperative prediction of OTVA origin site were determined by the above indicators.

  RESULTS  The difference of sensitivity, specificity, positive predictive value, negative predictive value and accuracy were not statistically significant when identifying the OTVA originated from the left and right ventricular outflow tract with the R-wave duration index and R/S-wave amplitude index,V2S/V3R index and TZ index.

  CONCLUSION  There is no significant difference in the predictive value of the three electrocardiogram indexes in predicting the origin of OTVA outflow tract.