右室流出道不同部位起搏患者体表心电图的特点

Characteristics of surface electrocardiogram in patients with pacing at different sites of right ventricular outflow tract

目的探讨体表心电图特点与右室流出道不同区域起搏的关系。方法入选186例行右室流出道起搏的患者,根据不同起搏位置,将患者分成间隔上部组(45例)、间隔下部组(24例)、前壁组(101例)及游离壁组(16例)。比较分析4组患者在右心室起搏状态下的体表心电图特点差异。结果 4组患者的临床一般资料比较,差异无统计学意义(P>0.05)。4组患者中,游离壁组QRS波时限为(173±14)ms,长于其他3组(P=0.014);QRS波群额面电轴间隔上部组为(61±47)°,而间隔下部组为(-18±52)°(P=0.01);间隔上部组胸前导联移行区指数(transitional zone Index,TZI)最小,而游离壁组最大(P=0.01);在4组患者肢体导联QRS主波方向比较中,间隔上部组下壁(Ⅱ,Ⅲ,a VF)导联QRS主波向上的比例最大。结论体表心电图特点有助于右室流出道起搏电极在不同区域的定位,但受样本量等的影响,仍需大样本的研究加以验证。

Objective To discuss the relationship between characteristics of surface electrocardiogram （ECG） and pacing at different sites of right ventricular outflow tract （RVOT）. Methods The patients undergone pacing of RVOT （n= 186） were chosen, and then divided into upper interval group （n=45）, lower interval group （n=24）, anterior wall group （n=101） and free wall group （n=16）. The difference in characteristics of surface ECG was compared among 4 groups under right ventricular pacing condition. Results The difference in general clinical data had no statistical significance among 4 groups （P〉0.05）. QRS duration was （173 ＋ 14） ms in free wall group, which was longer than that in other 3 groups （P=0.014）. QRS group frontal plane axis was （61 ± 47）° in upper interval group and （-18 ± 52） ° in lower interval group （P=0.01）. The precordial lead transitional zone index （TZI） was the minimum in upper interval group and the maximum in free wall group （P=0.01）. The comparison in QRS main wave vector in limb leads among 4 groups showed that the percentage of upward QRS main wave in inferior wall leads （ Ⅱ, Ⅲ and aVF） was the maximum in upper interval group. Conclusion The characteristics of surface ECG is conducive to locating the different sites of RVOT pacing, but more studies with larger sample size are needed to confirm the conclusion.