Deutsch H J, Smolorz J, Sechtem U, Hombach V, Schicha H, Hilger H H
Medical Clinic III, University of Cologne, FRG.
Int J Card Imaging. 1988;3(1):3-11. doi: 10.1007/BF01801639.
Gated magnetic resonance imaging of the heart displays cardiac structures with excellent resolution. This ability should be useful for assessment of cardiac physiology where acquisition of systolic and diastolic images is required. In this study, left ventricular ejection fraction was determined in 50 patients from oblique long axis views of the left ventricle using the area length formula. Angulated views were obtained by electronic gradient angulation. For comparison, all patients had monoplane angiocardiography in the RAO position. Forty-five patients were also studied by radionuclide ventriculography. Ejection fractions determined by MRI and angiocardiography were closely correlated (r = 0.90). Correlation between MRI and radionuclide ventriculography was also acceptable (r = 0.79). In addition to global left ventricular function, MR images provide information about regional wall motion. In order to acquire a three-dimensional set of images at various phases of the cardiac cycle, shorter imaging times are mandatory. A new imaging technique with potential for functional studies uses low flip angles, short repetition times and gradient refocused echoes. Up to 40 images can be obtained within one cardiac cycle. When displayed in a looped fashion, visual assessment of cardiac motion, intracardiac blood flow, and systolic wall thickening is possible. Potential advantages of functional studies by MRI are the concomitant acquisition of anatomical information and the three dimensional frame of reference.
心脏门控磁共振成像能够以出色的分辨率显示心脏结构。这种能力对于需要获取收缩期和舒张期图像的心脏生理学评估应该是有用的。在本研究中，使用面积长度公式从左心室的斜长轴视图中确定了50例患者的左心室射血分数。通过电子梯度角度调整获得成角度的视图。作为对照，所有患者均在右前斜位进行了单平面心血管造影。45例患者还接受了放射性核素心室造影检查。通过磁共振成像和心血管造影测定的射血分数密切相关（r = 0.90）。磁共振成像与放射性核素心室造影之间的相关性也可以接受（r = 0.79）。除了整体左心室功能外，磁共振图像还提供有关局部室壁运动的信息。为了在心动周期的各个阶段获取三维图像集，必须缩短成像时间。一种具有功能研究潜力的新成像技术使用低翻转角、短重复时间和梯度重聚回波。在一个心动周期内可获得多达40幅图像。当以循环方式显示时，就可以对心脏运动、心腔内血流和收缩期室壁增厚进行视觉评估。磁共振成像功能研究的潜在优势在于可同时获取解剖学信息和三维参考框架。
