aVL/aVR导联S波振幅比鉴别左冠窦起源室性期前收缩

Lead aVL/aVR S-wave amplitude ratio for identifying premature ventricular contraction originating from left coronary cusp

目的:探索aVL/aVR导联S波振幅比鉴别左冠窦(leftcoronarycusp,LCC)起源室性期前收缩(prematureventricularcontraction,PVC)的实用性。方法:回顾性分析2013年1月至2017年8月于中南大学湘雅二医院心血管内科住院治疗,并经体表心电图初步判断及导管射频消融术中腔内电生理图证实的特发性流出道PVC患者372例。比较起源于不同部位的PVC,其12导联体表心电图QRS波振幅之间的差异。结果:45例PVC起源于LCC,58例起源于右冠窦(right coronary cusp,RCC),269例起源于右室流出道(rightventricularoutflowtract,RVOT)。心电图QRS波相关参数中受试者工作特征曲线下面积(AUC)最大的指标为a VL/aVR导联S波振幅比,其在LCC组(1.69±0.74)高于RCC组(1.29±0.63,P<0.001)和RVOT组(0.84±0.48,P<0.001);其AUC值及95%CI为0.894(0.824～0.964),界值为1.50。a VL/aVR导联S波振幅比>1.50鉴别LCC起源PVC的敏感度、特异度及准确度分别为88.9%,91.4%和91.1%。结论:a VL/aVR导联S波振幅比在LCC起源PVC的鉴别中有一定价值。

Objective： To explore the validity of lead aVL/aVR S-wave amplitude ratio for identifying premature ventricular contractions（PVCs） originating from left coronary cusp（LCC）. Methods： This study retrospectively analyzed 372 PVCs patients who underwent successful radiofrequency catheter ablation at the Second Xiangya Hospital, Central South University between January 2013 and August 2017. We compared the QRS wave amplitudes in the surface 12-lead electrocardiography between PVCs originating from different sites. Results： The origin sites of PVCs were LCC（n=45）, right coronary cusp（RCC, n=58） and right ventricular outflow tract（RVOT, n=269）. The lead aVL/aVR S-wave amplitude ratio was significantly higher in the LCC group（1.69±0.74） than that in the RCC group（1.29±0.63, P〈0.001） and RVOT group（0.84±0.48, P〈0.001）. The area under the receiver operating characteristic curve（AUC） and 95%CI of lead aVL/aVR amplitude ratio which had the largest AUC for identifying LCC origin were 0.894（0.824–0.964）, and the cut-off was 1.50. The lead aVL/aVR S-wave amplitude ratio 1.50 was applied to developing a diagnosed method for identifying LCC origin and the sensitivity, specificity and accuracy were 88.9%, 91.4% and 91.1%, respectively. Conclusion： Lead aVL/aVR S-wave amplitude ratio could help to identify LCC originating PVCs.