Regional myocardial function: advances in MR imaging and analysis.

Abstract

Cardiovascular magnetic resonance (MR) imaging can provide three-dimensional analysis of global and regional cardiac function with great accuracy and reproducibility. Quantitative assessment of regional function with cardiac MR imaging previously was limited by long acquisition times and time-consuming analysis. The use of steady-state free precession cine MR imaging substantially improves assessment of myocardial wall motion. Advances in gradient technology and reconstruction techniques have increased MR image acquisition speed and made real-time cine MR imaging possible. Myocardial deformation may be measured with cine MR tagging, and interpretation of the resultant tagged MR images by means of harmonic phase analysis enables prompt and precise strain measurements. Velocity-encoded and stimulated-echo techniques such as phase-contrast MR imaging and displacement encoding with stimulated echoes, or DENSE, provide high-resolution strain maps. Clinical validation of these strain imaging techniques will depend on future assessments of their effect on the management of cardiac disease.