Objectives The aim of this study was to investigate the potential of coronary ultrafast Doppler angiography (CUDA), a novel vascular imaging technique based on ultrafast ultrasound, to image noninvasively with high sensitivity the intramyocardial coronary vasculature and quantify the coronary blood flow dynamics.

Background Noninvasive coronary imaging techniques are currently limited to the observation of the epicardial coronary arteries. However, many studies have highlighted the importance of the coronary microcirculation and microvascular disease.

Methods CUDA was performed in vivo in open-chest procedures in 9 swine. Ultrafast plane-wave imaging at 2,000 frames/s was combined to an adaptive spatiotemporal filtering to achieve ultrahigh-sensitive imaging of the coronary blood flows. Quantification of the flow change was performed during hyperemia after a 30-s left anterior descending (LAD) artery occlusion followed by reperfusion and was compared to gold standard measurements provided by a flowmeter probe placed at a proximal location on the LAD (n = 5). Coronary flow reserve was assessed during intravenous perfusion of adenosine. Vascular damages were evaluated during a second set of experiments in which the LAD was occluded for 90 min, followed by 150 min of reperfusion to induce myocardial infarction (n = 3). Finally, the transthoracic feasibility of CUDA was assessed on 2 adult and 2 pediatric volunteers.

Results Ultrahigh-sensitive cine loops of venous and arterial intramyocardial blood flows were obtained within 1 cardiac cycle. Quantification of the coronary flow changes during hyperemia was in good agreement with gold standard measurements (r² = 0.89), as well as the assessment of coronary flow reserve (2.35 ± 0.65 vs. 2.28 ± 0.84; p = NS). On the infarcted animals, CUDA images revealed the presence of strong hyperemia and the appearance of abnormal coronary vessel structures in the reperfused LAD territory. Finally, the feasibility of transthoracic coronary vasculature imaging was shown on 4 human volunteers.

Conclusions Ultrafast Doppler imaging can map the coronary vasculature with high sensitivity and quantify intramural coronary blood flow changes.

目的本研究的目的是探讨冠状动脉超快多普勒血管造影 (CUDA) 的潜力，这是一种基于超快超声的新型血管成像技术，可对心肌内冠状动脉血管系统进行高灵敏度无创成像并量化冠状动脉血流动力学。

背景无创冠状动脉成像技术目前仅限于心外膜冠状动脉的观察。然而，许多研究强调了冠状动脉微循环和微血管疾病的重要性。

方法CUDA 在 9 头猪体内进行开胸手术。将 2,000 帧/秒的超快平面波成像与自适应时空滤波相结合，以实现对冠状动脉血流的超高灵敏度成像。在 30 秒左前降支 (LAD) 动脉闭塞然后再灌注后充血期间对流量变化进行量化，并与放置在 LAD 近端位置的流量计探头提供的金标准测量值进行比较 (n = 5) . 在腺苷静脉灌注期间评估冠状动脉血流储备。在第二组实验中评估了血管损伤，其中 LAD 被阻塞 90 分钟，然后再灌注 150 分钟以诱导心肌梗塞 (n = 3)。最后，

结果在1个心动周期内获得了超高灵敏度的静脉和动脉心肌内血流循环。充血期间冠状动脉血流变化的量化与金标准测量值 (r ²  = 0.89) 以及冠状动脉血流储备的评估 (2.35 ± 0.65 vs. 2.28 ± 0.84; p = NS) 非常一致。在梗塞的动物身上，CUDA 图像显示在再灌注的 LAD 区域中存在强烈充血和异常冠状血管结构的出现。最后，在 4 名人类志愿者身上展示了经胸冠状动脉血管成像的可行性。

结论超快多普勒成像可以高灵敏度地绘制冠状动脉血管，量化冠状动脉壁内血流变化。