糖尿病患者冠状动脉左前降支远段血流动力学变化的超声研究

目的应用冠脉血流显像技术观察分析糖尿病患者静息状态下左前降支(LAD)远段血流动力学改变,了解该变化与心肌微血管损害之间的关系。方法对31例非胰岛素依赖性糖尿病患者进行冠脉多普勒血流显像检查,观察LAD远段在静息状态下的冠脉血流信号,记录流速曲线,测定收缩期峰值速度(SPV),收缩期速度时间积分(VTIs),舒张期峰值速度(DPV),舒张期速度时间积分(VTId),舒张期加速时间(TPVd),舒张期减速度(DDR)以及舒张期减速时间(DDD),并与正常对照组进行比较。结果31例患者中有2例未测及前降支远段血流,其余29例均能较清晰显示,SPV、DPV与正常对照组比较无显著性意义VTIs、VTId、TPVd和DDD明显低于正常对照组(P<0.01),DDR高于正常对照组(P<0.05)。结论糖尿病患者心肌内微血管的损害可以影响心外膜冠脉的血流动力学,而经胸冠脉多普勒血流显像能直接观测前降支远段冠脉血流,早期发现糖尿病患者潜在的心肌缺血。

Hemodynamic Changes of the Distal Left Anterior Descending Artery by Ultrasound in Diabetic Patients

Objective To observe and analyze the hemodynamic changes of the distal left anterior descending artery by transthoracic color Doppler echocardiography(TTDE) and to determine the relations between those changs and the microvascular impairments.Methods Twenty-four normal subjects and thirty-one patients were studied.The distal LAD flow signal was observed and the pulsed-Doppler velocity curve was recorded by TTDE.Systolic peak velocity(SPV),systolic velocity time integrity(VTIs),diastolic peak velocity(DPV),diastolic velocity time integrity(VTId),time from the beginning of diastole to diastolic peak velocity(TPVd),diastolic deceleration rate (DDR),diastolic deceleration duration(DDD) were measured.Results The distal LAD flow signal could be observed in all cases of normal subjects and 29 cases in patients.SPV,DPV had no significant difference between the patients and the controls.VTIs,VTId,TPVd and DDD were significantly lower in patients than those in controls(P<0.01),DDR was higher in patients than in controls(P<0.05).Conclusions the intramyocardial microvascular impairments in diabetic patients may affect the flow dynamics of epicardial coronary artery.The increased microcirculation resistance and decreased coronary perfused capacity may contribute to the changes.Monitoring of the distal LAD flow velocity by TTDE was useful in early detecting latent myocardial ischemia in diabetic patients.