Risk stratification in coronary artery disease is an ongoing challenge for which few tools are available for quantifying physiology within coronary arteries. Recently, anatomy-driven computational fluid dynamic modeling has enabled the mapping of local flow dynamics in coronary stenoses, with derived parameters such as WSS exhibiting a strong capability for predicting adverse clinical events on a patient-specific basis. As cardiac catheterization is common in patients with coronary artery disease, minimally invasive technologies capable of identifying pathologic flow in situ in real time could have a significant impact on clinical decision- making. As a step toward in vivo quantification of slow flow near the arterial wall, proof-of-concept for 3-D intravascular imaging of blood flow dynamics is provided using a 118-element forward-viewing ring array transducer and a research ultrasound system. Blood flow velocity components are estimated in the direction of primary flow using an unfocused wave Doppler approach, and in the lateral and elevation directions, using a transverse oscillation approach. This intravascular 3-D vector velocity system is illustrated by acquiring real-time 3-D data sets in phantom experiments and in vivo in the femoral artery of a pig. The effect of the catheter on blood flow dynamics is also experimentally assessed in flow phantoms with both straight and stenotic vessels. Results indicate that 3-D flow dynamics can be measured using a small form factor device and that a hollow catheter design may provide minimal disturbance to flow measurements in a stenosis (peak velocity: 54.97 ± 2.13 cm/s without catheter vs. 51.37 ± 1.08 cm/s with hollow catheter, 6.5% error). In the future, such technologies could enable estimation of 3-D flow dynamics near the wall in patients already undergoing catheterization.

冠状动脉疾病的风险分层是一项持续的挑战，很少有工具可用于量化冠状动脉内的生理学。最近，解剖学驱动的计算流体动力学建模能够绘制冠状动脉狭窄中的局部流动动力学，其衍生参数（如 WSS）表现出强大的能力，可以预测特定患者的不良临床事件。由于心导管检查在冠状动脉疾病患者中很常见，因此能够实时识别原位病理流动的微创技术可能会对临床决策产生重大影响。作为迈向体内的一步为了量化动脉壁附近的慢流，使用 118 元件前视环形阵列换能器和研究超声系统提供了血流动力学 3-D 血管内成像的概念验证。使用非聚焦波多普勒方法在主要血流方向上估计血流速度分量，使用横向振荡方法在横向和仰角方向上估计血流速度分量。通过在体模实验和体内获取实时 3-D 数据集来说明这种血管内 3-D 矢量速度系统在猪的股动脉中。导管对血流动力学的影响也在具有直血管和狭窄血管的流动模型中进行了实验评估。结果表明，可以使用小尺寸设备测量 3-D 流动动力学，并且中空导管设计可以对狭窄处的流动测量提供最小干扰（峰值速度：54.97 ± 2.13 cm/s，无导管对比 51.37 ± 1.08 cm/s 中空导管，6.5% 误差）。未来，这些技术可以估计已经接受导管插入术的患者壁附近的 3-D 流动动力学。