向量血流成像技术定量评价冠心病患者左心室心肌局部功能的研究

摘要

Objective To investigate blood flow dynamics adjacent to regional myocardial segments in coronary artery disease(CAD) patients and to explore the association of the two CAD features.Methods In 43 CAD patients,velocity vector imaging (VVI) was used to evaluate the wall motion and classify normal myocardial segments (NS),relatively abnormal and obviously abnormal wall motion segments (RS and OS) by systolic peak strain (Ss).Vector flow mapping (VFM) was used to show blood flow dynamics in the heart chamber,including blood flow (Q) heading towards or away from the apex during a heart beat and time to every peak flow (T).Results Compared with NS,both RS and OS showed a higher systole Q + (blood flow heading towards the apex during systole) and lower diastole Q + (blood flow heading towards the apex during diastole) and shortened T2 (adjusted time interval between E and A peaks).Systole Q + was positively correlated with Ss but negatively with segmental ejection fraction (SEF).Diastole Q + was negatively correlated with early and late diastolic peak velocity (Ve and Va) but positively with Ve/Va.T2 was negatively correlated with Ve but positively with Ve/Va and early diastolic peak strain rate (SRe).Conclusions VFM might be a new tool to quantitatively assess change in regional blood flow dynamics in patients with CAD.%目的 应用向量血流成像(VFM)技术观察冠心病患者缺血心肌及梗死心肌心腔内局部血流动力学的变化,探讨室壁动度与心腔内血流动力学的相关性并寻找能较好反映室壁动度异常导致心腔内血流动力学改变的敏感指标.方法 对43例冠心病患者应用速度向量成像(VVI)技术定量评价心肌运动情况,并根据收缩期峰值应变(Ss)将心肌节段分为正常节段(NS)、临界节段(RS)及明显异常节段(OS).应用VFM技术显示各节段邻近心腔内的血流情况,包括在单个心动周期内朝向(正向)及背离(负向)探头的流量(Q),以及达到峰值流量所需的时间(T).结果 与正常组相比,RS及OS组收缩期正向血流量(systole Q+)增加[(27.08±3.81) cm2/s对(19.00±1.49) cm2/s,P＜0.05和(34.38±6.65) cm2/s对(19.00±1.49) cm2/s,P ＜0.01],舒张期正向血流量(diastole Q+)减低[(81.32±6.55) cm2/s对(103.55±4.37) cm2/s,P＜0.05和(61.92±10.13)cm2/s对(103.55±4.37) cm2/s,P＜0.01],校正后舒张期双峰间隔(T2)缩短[(0.292±0.010)对(0.340±0.005)和(0.099±0.016)对(0.340±0.005),P均＜0.01].Systole Q+与Ss呈正相关,但与心肌节段射血分数(SEF)呈负相关.Diastole Q+与心肌舒张早、晚期峰值速度(Ve和Va)呈负相关,但与Ve/Va呈正相关.T2与Ve呈负相关,但与Ve/Va及舒张早期峰值应变率(SRe)呈正相关.结论 VFM技术有望成为定量评价冠心病患者局部心腔内血流动力学改变的新方法.