Abstract：Objective To analyze the ECG characteristics of patients with idiopathic outflow tract premature ventricular contraction (PVC) and summarize the algorithm of predicting the origin sites of idiopathic outflow tract PVC. Methods One hundred and two patients with successful radiofrequency ablation for PVC were enrolled in our study. Multiple ECG indicators were analyzed for all patients, and multiple ECG indicators of different parts of the outflow tract were statistically analyzed. The number of cases with various characteristic indicators in different parts of the idiopathic outflow tract PVC were statistically analyzed. Results The figure of left bundle branch block is the best evaluation index to distinguish origin sites of PVC among the right ventricular outflow tract and the aortic valve area close to its anatomical position and other left ventricular outflow tract. The V2 leading index of the right ventricular outflow tract was much lower than that of the aortic valve region. Ratio of R/S amplitude index≥30% in leads V1 and V2 of right ventricular outflow tract was significantly lower than that of aortic valve area of left ventricular outflow tract or left ventricular outflow tract aortic valvemitral valve junction area. The ratio of Rwave time limit index≥50% in leads V1 and V2 of right ventricular outflow tract was significantly lower than that in aortic valve area of left ventricular outflow tract. Conclusion The ECG of different origin sites of idiopathic outflow tract PVC has different characteristic manifestations, which is of great significance for accurate positioning of radiofrequency ablation.
