右心室流出道起源室性期前收缩患者左心室收缩同步性及时序的研究

目的 分析正常人及右室流出道(right ventricular outflow tract,RVOT)起源室性期前收缩(premature ventricular complexes,PVCs)患者收缩期应变达峰时间,探讨RVOT起源PVCs患者心肌收缩同步性及时序规律.方法 应用斑点追踪成像(speckle tracking imaging,STI)技术测量30例RVOT起源PVCs患者在窦性心搏、室性心搏时及30例正常人纵向(TsL)、环周(TsC)、径向(TsR)收缩期应变达峰时间,分别计算标准差,并分析室性心搏时各方向应变达峰时间时序分布规律.结果 与正常对照组比较,RVOT起源PVCs患者在室性心搏时TsL、TsC、TsR标准差均增大,窦性心搏时TsC、TsR标准差增大.室性心搏时,TsL、TsR从心尖至基底的不同层面间差异显著;TsL、TsC在不同室壁间差异显著.结论 RVOT起源PVCs患者在窦性心搏及室性心搏时均存在失同步状态,其中室性心搏时各方向应变达峰时间时序分布存在规律.

Study of left ventricular systolic synchrony and sequence in patients with premature ventricular complexes from right ventricular outflow tract

Objective To evaluate left ventricular(LV) systolic synchrony and sequence in patients with premature ventricular complexes(PVCs) from right ventricular outflow tract (RVOT).Methods Thirty patients with frequent isolated PVCs from RVOT and 30 healthy subjects as control were included.Speckle tracking imaging (STI) was performed to assess the time-to-peak segmental systolic strain in longit udinal(TsL), circumferential (TsC) and radial (TsR) direction.The standard deviation (SD) of TsL,TsC and TsR of 18 LV segments were calculated respectively.All values of patients with PVCs were recorded during sinus beats(PVC-S) and PVC beats(PVC-V) respectively.LV systolic sequence in PVC-V was analyzed.Results Significant differences were observed in the SD values between the PVC-V and control subjects in three directions,as well as between the PVC-S and control subjects in circumferential and radial direction.In PVC-V significance difference was seen in TsL and TsR from apical to basal level,as well as in TsL and TsC in different walls.Conclusions LV systolic synchrony was demonstrated in patients with PVCs from RVOT during both sinus beats and PVC beats.Systolic sequence in PVC beats from RVOT exhibit certain rules.