ECG characteristics of left and right ventricular origin in outflow tract premature ventricular contraction with V3 migration of precordial lead / 中国综合临床

ABSTRACT

Objective:To investigate the electrocardiographic characteristics of left and right ventricles origin of premature ventricular contractions(PVCs) during V3 transition of precordial leads, right ventricular outflow tract (RVOT) anterior septum and right coronary sinus (RCC), and RVOT middle-posterior septum and left coronary sinus (LCC).Methods:From January 2017 to September 2019, 91 patients with ventricular extrasystole of outflow tract who had V3 transition in precordial lead and had successful radiofrequency ablation in RVOT anterior septum, middle posterior septum, LCC and RCC were selected for retrospective case control study.The electrocardiography measurements of PVCs were compared between the anteroseptal RVOT group and RCC group, as well as the middle-posterior septal RVOT group and the LCC group, respectively.The measurements included the R-wave amplitude in lead Ⅰ, Ⅱ, Ⅲ and aVF, R amplitude ratio in leads Ⅲ to Ⅱ, Q-wave amplitude in lead aVL and aVR, Q amplitude ratio in leads aVL to aVR, R-wave and S-wave amplitude from leads V1 to V3, the V2S/V3R index, the transition zone index, and the V2 transition ratio.Results:Thirty-six cases originated from the anteroseptal RVOT, and 11 from the LCC.Lead I R-wave amplitude in anterior septal RVOT was higher than LCC group((0.22±0.25) mV vs.(-0.17±0.33) mV; P=0.003). R-wave amplitude in lead Ⅱ was lower than that in the LCC group((1.59±0.35) mV vs.(1.76±0.27) mV; P=0.035). R-wave amplitude in lead aVF was lower compared with the LCC group((1.53±0.35) mV vs.(1.78±0.39) mV; P=0.050). The V2S/V3R index showed a significant difference between these two groups(1.99±0.66 vs.0.76±0.38; P<0.001). The V2 transition ratio also appeared a significant difference between the two groups(0.69±0.43 vs.1.05±0.35; P=0.005). PVCs arose from the middle-posterior septal RVOT in 32 cases, and from the RCC in 12 cases.Compared with RCC group, lead Ⅰ R-wave amplitude showed lower ((0.25±0.31) mV vs.(0.57±0.12) mV; P<0.001); R amplitude ratio in leads Ⅲ to Ⅱ higher (0.89±0.14 vs.0.72±0.18; P=0.002); Q amplitude in lead aVL((0.72±0.24) mV vs.(0.51±0.16) mV; P=0.002)higher, and Q amplitude ratio in leads aVL to aVR higher in the middle-posterior septal RVOT(0.76±0.23 vs.0.50±0.21; P=0.002). Conclusion:Among the cases with lead V3 transition, PVCs originated from the anteroseptal RVOT show significantly different R wave in lead Ⅰ, Ⅱ, aVF, V2S/V3R index, and the V2 transition ratio compared with those from the LCC.The PVCs from the middle-posterior septal RVOT and the RCC have different R wave in lead Ⅰ, R amplitude ratio in leads Ⅱ and Ⅲ, Q amplitude ratio in leads aVL and aVR.Combined with its different characteristics, it can help to identify the origin of left and right ventricles.