Pasquet A, Armstrong G, Rimmerman C, Marwick T H
Department of Cardiology, Cleveland Clinic Foundation, Ohio, USA.
Am J Cardiol. 2000 Mar 1;85(5):536-42. doi: 10.1016/s0002-9149(99)00807-3.
Myocardial Doppler velocity (MDV) imaging may provide an objective correlate of ischemia, thereby reducing the expertise needed for interpreting stress echocardiography and improving its reproducibility. This study sought to independently validate the results of exercise MDV imaging with single-photon emission computed tomography (SPECT) perfusion imaging in 116 patients (age 60+/-12 years, 28 women) referred for exercise SPECT for diagnostic or prognostic assessment of coronary artery disease. Two-dimensional echocardiography was performed with simultaneous color MDV data acquisition before and after exercise treadmill testing. MDV data were processed off-line to display myocardial velocity profiles in each segment at rest and peak exercise. SPECT was analyzed using a 16-segment model and segments were classified as normal or showing resting or stress defects. Resting defects within segments showing normal function were attributed to attenuation. Color MDV data were compared with SPECT results, and a multivariate analysis (including exercise and SPECT results) was performed to identify the determinants of the exercise MDV response. Patients exercised maximally (peak rate-pressure product 27.6+/-6.1x10(3), and SPECT was abnormal in 33 patients. Of the 1,333 left ventricular segments evaluable by SPECT and MDV, 1,217 segments were classified as normal, 43 showed a stress defect, and 73 a rest defect. Segmental comparison of thallium findings and MDV showed that segments with a rest defect had a lower velocity at rest and stress than normal segments (p<0.001). Segments with a stress defect had a marked reduction in peak exercise velocity and less increment in velocity than normal segments. Heart rate, functional capacity, and presence of abnormally perfused segments were independent predictors of myocardial velocity at peak exercise. Thus, color MDV correlates with independent evidence of ischemia, although it is also influenced by exercise capacity and left ventricular function. This technique may permit a feasible approach to quantitation of exercise echocardiography.
心肌多普勒速度（MDV）成像可能提供缺血的客观相关指标，从而减少解读负荷超声心动图所需的专业知识，并提高其可重复性。本研究旨在独立验证116例（年龄60±12岁，28例女性）因诊断或评估冠状动脉疾病预后而接受运动单光子发射计算机断层扫描（SPECT）的患者运动MDV成像结果与SPECT灌注成像结果的一致性。在运动平板试验前后，进行二维超声心动图检查并同步采集彩色MDV数据。MDV数据离线处理，以显示静息和运动高峰时各节段的心肌速度剖面图。SPECT采用16节段模型分析，节段分为正常或显示静息或负荷缺损。功能正常节段内的静息缺损归因于衰减。将彩色MDV数据与SPECT结果进行比较，并进行多因素分析（包括运动和SPECT结果）以确定运动MDV反应的决定因素。患者进行最大运动（峰值心率血压乘积27.6±6.1×10³），33例患者SPECT异常。在可通过SPECT和MDV评估的1333个左心室节段中，1217个节段分类为正常，43个显示负荷缺损，73个显示静息缺损。铊显像结果与MDV的节段比较显示，有静息缺损的节段在静息和负荷时的速度低于正常节段（p<0.001）。有负荷缺损的节段运动高峰时速度明显降低，速度增量低于正常节段。心率﹑功能能力和灌注异常节段的存在是运动高峰时心肌速度的独立预测因素。因此，彩色MDV与缺血的独立证据相关，尽管它也受运动能力和左心室功能的影响。该技术可能为运动超声心动图的定量分析提供一种可行的方法。
