[Quantitative analysis of left ventricular wall motion with MRI tagging].
OBJECTIVE
The purpose of this study was to establish a quantification of different parameters of left ventricular wall motion from tagged MR images. This evaluation method was to be applied to characterize the physiological contraction cycle and to determine pathophysiological changes.


METHODS
Myocardial tagging was performed at a basal, a mid-ventricular and an apical level of the left ventricle. A suitable software was programmed for the automatic quantification of rotation, contraction and circumferential shortening. The evaluation method was used in 8 healthy volunteers, 13 patients suffering from aortic stenosis before and one year after surgery and in 10 patients with myocardial infarction before and after revascularization.


RESULTS
The software allows the quantification of left ventricular wall motion by assessment of rotation, contraction and circumferential shortening. In the healthy volunteers, there was a wringing motion with opposite rotation of base and apex of the heart. Before valve replacement, patients with aortic stenosis showed significantly increased apical rotation and torsion. One year after surgery, left-ventricular torsion had normalized. In patients with myocardial infarction, circumferential shortening increased after revascularization.


CONCLUSIONS
The quantification of left ventricular wall motion using tagged MR images allows to characterize and follow-up changes of left ventricular wall motion in various diseases of the heart.
Johnson
T
T
Institut für Klinische Radiologie, Klinikum Grosshadern der Ludwig-Maximilians-Universität München. thorsten.johnson@med.uni-muenchen.de
Hahn
D
D
Sandstede
J
J
D000368:Aged; D001024:Aortic Valve Stenosis / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D001026:Coronary Artery Bypass; D005260:Female; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D011183:Postoperative Complications / Q000175:diagnosis* / Q000503:physiopathology; D012016:Reference Values; D012680:Sensitivity and Specificity; D012984:Software; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D016277:Ventricular Function, Left / Q000502:physiology*