Scheuble A, Feldman L J, Brochet E, Vahanian A, Steg P G
Service de cardiologie, hôpital Bichat, 46, rue Henri Huchard, 75877 Paris.
Arch Mal Coeur Vaiss. 2003 Jun;96 Spec No 5:25-33.
Coronary flow reserve is the ability of coronary flow to increase above its basal value when the coronary vascular bed is maximally dilated. It is a global parameter of coronary flow, which is early altered in the presence of epicardial coronary artery stenosis or a coronary microcirculation disorder. Until now, clinical use of coronary flow reserve has been hampered by the lack of an easy, reliable and non-invasive method. Recently developed high-frequency transthoracic Doppler echocardiography now allows non-invasive assessment of coronary flow reserve. After an initial learning curve, it is possible to study coronary flow, essentially in the left anterior descending artery. Coronary flow reserve is expressed as the ratio of maximal hyperaemic to basal mean coronary velocity. Maximal hyperaemic flow is obtained with adenosine. Clinical applications of coronary flow reserve are numerous. Coronary flow reserve enables the assessment of hemodynamic relevance of a moderate coronary stenosis. Detection of coronary restenosis is also possible by repeated non-invasive measurement of coronary flow reserve. Moreover, evaluation of the microcirculation is of crucial importance in order to appreciate myocardial reperfusion following successful recanalisation on the infarct-related artery. Transthoracic Doppler echocardiography could allow identification of "no-reflow" by analysis of coronary flow pattern and coronary flow reserve. Furthermore, transthoracic Doppler echocardiography constitutes one of the only available and simple means to evaluate microcirculatory disorders (hypertension, diabetes,...). Finally, the possibility of non-invasive follow-up of arterial bypasses constitutes a major advantage of this technique.
冠状动脉血流储备是指当冠状动脉血管床最大程度扩张时，冠状动脉血流高于其基础值增加的能力。它是冠状动脉血流的一个整体参数，在心外膜冠状动脉狭窄或冠状动脉微循环障碍时会早期发生改变。到目前为止，由于缺乏一种简便、可靠且无创的方法，冠状动脉血流储备的临床应用受到了阻碍。最近开发的高频经胸多普勒超声心动图现在允许对冠状动脉血流储备进行无创评估。经过最初的学习曲线后，基本上可以研究左前降支的冠状动脉血流。冠状动脉血流储备表示为最大充血期与基础平均冠状动脉流速之比。最大充血期血流通过腺苷获得。冠状动脉血流储备的临床应用众多。冠状动脉血流储备能够评估中度冠状动脉狭窄的血流动力学相关性。通过重复无创测量冠状动脉血流储备也可以检测冠状动脉再狭窄。此外，评估微循环对于了解梗死相关动脉成功再通后的心肌再灌注至关重要。经胸多普勒超声心动图可以通过分析冠状动脉血流模式和冠状动脉血流储备来识别“无复流”。此外，经胸多普勒超声心动图是评估微循环障碍（高血压、糖尿病等）的唯一可用且简单的方法之一。最后，对动脉搭桥进行无创随访的可能性是该技术的一个主要优点。
