| Popis: |
The most relevant issues in the assessment of patients with valvular heart disease are the detection of valve lesion severity, the morphological description of heart valve and subvalvular structures, and the assessment of changes of the ventricles and the pulmonary circulation. MR imaging is an excellent, accurate and reproducible tool for the assessment of valve lesion severity and to monitor cardiac adaptation to volume and/or pressureoverload. An excellent overview of MR imaging in valvular disease is given by Schwitter 42. Due to the unique capability of MR techniques to measure flow, MR flow-velocity mapping may be particularly useful in quantification of regurgitant lesions and also in the serial assessment of changes of the heart. In the determination of stenotic lesion severity, MR imaging offers no direct advantages over echocardiography provided that echocardiographic window is adequate. Generally, 2-D echocardiography is the first method of choice in the assessment of valve lesion severity. Currently, MR techniques are generally accepted as a highly accurate technique for noninvasive measurement of blood flow, quantification of chamber dimensions, and assessment of ventricular function. With MR imaging it is possible to acquire data of lesion severity, left ventricular dimensions, and left ventricular function within 1 hour or less. In the near future, real time imaging capabilities will become routine and will shorten MR studies substantially. Consequently, there is a growing potential for application of MR imaging in patients with suspected or known valvular heart disease. |
