[Mass and geometry of the left ventricle. Contribution of ultrafast computed x-ray tomography and magnetic resonance imaging]. / Masse et géométrie ventriculaire gauche. Apports de la tomodensitométrie ultrarapide et de l'imagerie par résonance magnétique.

ABSTRACT

Ultrafast computed tomography and magnetic resonance imaging are two new methods of cardiac imaging. Measurements of left ventricular volume (end-diastolic, end-systolic volume, stroke volume) and mass have been validated with both methods. The calculations are independent of the geometric shape of the ventricle. Although regional analysis is difficult because of the complex movement of the left ventricle in the tomographic cuts, these methods present a number of advantages excellent temporospatial tomographic resolution, approximately the same in all dimensions, appreciation of endocardial movement from an epicardial centre, the potential to record their transform spatial data in 3 dimensions from initial planar acquisition. However, all potential regional measurements are still being validated as they are operator-dependent and require visual identification and manual tracing of the cardiac contours or local infrastructures which affect the results of these techniques which are still relatively little used in cardiac imaging. In the context of clinical evaluation, these relatively non-invasive methods will become extremely accurate in the appreciation of parameters of left ventricular geometry and function. They will become very useful in the determination of the myocardial effects of drugs, surgery or other interventional procedures in different models of cardiac disease.