Broillet A, Puginier J, Ventrone R, Schneider M
Bracco Research, SA, Carouge-Geneva, Switzerland.
Invest Radiol. 1998 Apr;33(4):209-15. doi: 10.1097/00004424-199804000-00003.
The authors evaluated the potential of SonoVue, a new echo contrast agent, for the detection of myocardial perfusion abnormalities using intermittent harmonic power Doppler (IHPD) imaging and different pulse repetition frequencies (PRFs).
Experiments were performed in vitro (in a tissue-mimicking phantom) and in vivo (in minipigs) in harmonic power Doppler using an ATL HDI 3000 with second harmonic software. SonoVue was injected intravenously in an auricular vein in bolus (dose range 0.01-0.05 mL/kg) in closed-chest animals or as an infusion (rate = 0.1 mL/kg/minute) in open-chest minipigs with reversible left anterior descending coronary artery (LAD) occlusion. The animals were imaged using IHPD gated on the electrocardiogram at end-systole (pulsing interval at each cardiac cycle). The efficacy of SonoVue was evaluated at six PRFs from 500 to 6000 Hz either qualitatively using a subjective scoring system or quantitatively using a digital image analyzer.
SonoVue at a dose of 0.01 mL/kg produced a strong and homogeneous myocardial opacification in IHPD. Higher doses prolonged the duration of the contrast effect. Varying the PRF allowed the discrimination of flow velocities in vitro and the detection of perfusion differences within the myocardium during transient LAD occlusion and during immediate reperfusion in vivo. Low PRFs were particularly useful to differentiate the ischemic bed from the healthy one during LAD occlusion. The high flows caused by coronary hyperemia during immediate reperfusion were detected clearly in the reperfused area at high PRFs.
SonoVue is a promising agent for myocardial opacification studies using IHPD. The latter imaging modality is particularly well suited for blood flow detection in tissues. Varying the PRF provides additional information on flow velocity and improves the detection of perfusion differences in the myocardium.
作者评估了新型超声造影剂声诺维（SonoVue）在使用间歇性谐波功率多普勒（IHPD）成像及不同脉冲重复频率（PRF）检测心肌灌注异常方面的潜力。
实验分别在体外（组织模拟体模）和体内（小型猪）进行，使用配备二次谐波软件的ATL HDI 3000进行谐波功率多普勒检查。在闭胸动物的耳静脉中静脉推注声诺维（剂量范围0.01 - 0.05 mL/kg），或在开胸小型猪中以0.1 mL/kg/分钟的速率输注声诺维，这些小型猪存在可逆性左前降支冠状动脉（LAD）闭塞。在心电图的收缩末期（每个心动周期的脉冲间隔）使用IHPD对动物进行成像。使用主观评分系统定性或使用数字图像分析仪定量评估声诺维在500至6000 Hz的六个PRF下的效果。
剂量为0.01 mL/kg的声诺维在IHPD中产生强烈且均匀的心肌显影。更高剂量可延长造影效果的持续时间。改变PRF能够在体外区分流速，并在体内检测LAD短暂闭塞期间及即刻再灌注期间心肌内的灌注差异。低PRF在LAD闭塞期间特别有助于区分缺血区和健康区。在高PRF下，再灌注区域能清晰检测到即刻再灌注期间冠状动脉充血引起的高血流。
声诺维是一种有前景的用于IHPD心肌显影研究的造影剂。后一种成像方式特别适合于组织内血流检测。改变PRF可提供关于流速的额外信息，并改善心肌灌注差异的检测。
