Furber A, Sakuma H, Higgins C B
Service de cardiologie, CHU Angers.
Arch Mal Coeur Vaiss. 1997 Nov;90(11):1501-10.
The high spatial and temporal resolution of MRI provides accurate identification of left ventricular endocardial and epicardial contours. Cine-MRI allows reliable and reproducible measurements of end-systolic and end-diastolic volumes, ejection fraction and left ventricular mass. These measurements are not based on any geometrical hypothesis and so remain valid in presence of ventricular deformation as observed after myocardial infarctions. The value of cine-MRI has been demonstrated in ischaemic heart disease for the study of regional left ventricular function, by analysis of left ventricular segmental function and systolic thickening of the myocardial walls. Cine-MRI may also be performed during pharmacological stress. In coronary patients without ventricular dysfunction at rest, stress cine-MRI enables detection of segmental wall motion abnormalities or reduction of systolic thickening in potentially ischaemic territories. Cine-MRI may contribute to be study of myocardial viability. Regional myocardial perfusion may also be assessed using the rapid sequences of imaging and contrast agents opacifying the intravascular compartment. In coronary patient, underperfused regions may there by be detected. The most rapid imaging techniques enable visualisation of the proximal segments of the coronary arteries and the measurement of blood velocity in the coronary arteries and the calculation of coronary reserve. Simultaneous analysis under basal conditions and after pharmacological stress of global and segmental left ventricular function and of myocardial perfusion, associated with the possibility of imaging the proximal coronary arteries and of measuring the velocity of coronary flow, makes MRI a complete non-invasive method of evaluating patients with ischaemic heart disease.
MRI的高空间和时间分辨率可精确识别左心室的心内膜和心外膜轮廓。电影MRI能够可靠且可重复地测量收缩末期和舒张末期容积、射血分数以及左心室质量。这些测量并非基于任何几何假设，因此在心肌梗死后观察到的心室变形情况下仍然有效。电影MRI在缺血性心脏病中对于研究局部左心室功能的价值已得到证实，通过分析左心室节段功能和心肌壁的收缩增厚情况。电影MRI也可在药物负荷试验期间进行。对于静息时无心室功能障碍的冠心病患者，负荷电影MRI能够检测潜在缺血区域的节段性室壁运动异常或收缩增厚减弱。电影MRI有助于心肌存活情况的研究。也可使用使血管内腔显影的快速成像序列和造影剂来评估局部心肌灌注。在冠心病患者中，由此可检测到灌注不足区域。最快速的成像技术能够显示冠状动脉近端节段，并测量冠状动脉内的血流速度以及计算冠状动脉储备。在基础状态下以及药物负荷试验后对整体和节段性左心室功能以及心肌灌注进行同步分析，再加上能够对冠状动脉近端进行成像以及测量冠状动脉血流速度，使得MRI成为评估缺血性心脏病患者的一种完整的非侵入性方法。
