合并室性心动过速的流出道室性早搏体表心电图特点

Electrocardiographic characteristics of idiopathic outflow tract ventricular premature with monomorphic tachycardia

目的通过分析合并持续性单形性室性心动过速(室速)的特发性流出道室性早搏(室早)和未合并室速的流出道室早的心电图指标,寻找流出道室早合并室速的心电图预测因素。方法入选33例合并持续性单形性室速的特发性流出道频发室早患者(室速组)和37例未合并室速的特发性流出道频发室早患者(室早组)。分析比较两组基线数据及心电图相关指标,包括室早指数、联律间期、联律间期指数、T波峰末间期(Tp-Te)、窦性心律QRS波时限、室早前RR间期、QTc、QTS碎裂波等的差异。结果两组患者基线资料无显著差异,室速组患者QRS波时限[(101.33±19. 46) ms vs.(89. 40±14.02) ms]、Tp-Te[(141.1±78.55) ms vs.(76.60±23.29) ms]、联律间期指数(0.71±0.17 vs.0.62±0.10)均明显大于室早组(P均<0.05),室速组的室早指数明显小于室早组(1.34±0.19 vs.1.64±0. 60,P <0.05)。多因素回归分析显示,联律间期指数(OR值=270.03)和Tp-Te(OR值=1.025)是室早合并持续性室速的独立预测指标,其界值分别为0.74(灵敏度45.5%,特异度89.2%)和94 ms(灵敏度57.6%,特异度89.2%)。结论联律间期指数和Tp-Te是特发性流出道室早患者是否合并持续性单形性室速的独立预测指标,流出道室早患者心电图联律间期指数越大和Tp-Te越长,发生持续性室速的风险越高。

Objective To clarify the electrocardiographic characteristics of outflow tract ventricular premature ventricular contraction( OT-PVC) with ventricular tachycardia( VT) by comparing the electrocardiographic parameters between OT-PVC with VT and OT-PVC without VT. Methods Thirty-three patients with sustained OT-VT which had monomorphic QRS morphology( VT group) and 37 patients with frequent OT-PVC( PVC group) were enrolled. The prematurity index( PI),coupling interval( CI),interval from the peak to the end of the T wave( TpTe),duration of QRS complex during sinus rhythm,sinus cycle length,CI index,QT interval,QTc and incidence of fragmented QRS complexes were compared between the two groups. Results No difference existed in baseline characteristics between the two groups. The duration of QRS complex [(101. 33 ± 19. 46) ms vs.(89. 40 ± 14. 02) ms],Tp-Te [(141. 1 ± 78. 55) ms vs.(76. 60 ± 23. 29) ms],CI index(0. 71 ± 0. 17 vs. 0. 62 ± 0. 10) in the VT group were significantly prolonged versus PVC group( P < 0. 05). PI(1. 34 ± 0. 19 vs. 1. 64 ± 0. 60,P < 0. 05) in the VT group was shorter than PVC group. Logistic regression analysis revealed that CI index and Tp-Te were the determinants of transition from OT-PVC to monomorphic OT-VT( odd ratio = 270. 03 and 1. 025,respectively). A CI index value greater than 0. 74 predicted sustained VT with a sensitivety of 45. 5% and specicity of 89. 2%,and a Tp-Te greater than 94 ms predicted sustained VT with a sensitivety of 57. 6% and specicity of 89. 2%. Conclusion PI and Tp-Te may be the predictors of the OT-PVC with monomorphic OT-VT,and OT-PVC with longer PI and Tp-Te may have a higher possibility to transform to OT-VT.