Augmented Long-Axis Acquisition in Cardiac Magnetic Resonance Imaging Improves Cardiac Strain Accuracy

Cine cardiac magnetic resonance (CMR) imaging is a common imaging modality in the clinical assessment of several cardiovascular diseases. Structural indices, such as cardiac strains obtained through cardiac motion analysis, are important in the early-stage assessment of structural heart diseases. Despite the benefits of such imaging techniques, motion estimation algorithms are susceptible to variability. Accurate motion tracking is challenged by factors such as image artifacts and spatiotemporal strain heterogeneity. This study systematically investigates CMR-based strain calculations to evaluate the most suitable image acquisition strategy for capturing the heterogeneous variations in radial and circumferential strains. A parametric study evaluating cardiac strains using synthetic heart model phantoms and mouse-specific CMR imaging is used to identify the association between various image acqui-sition strategies and accurate motion tracking. Through structural similarity and mean squared error analysis, a combined stack of short-axis and two long-axis images was observed to capture the distinct variations in anatomical strain patterns, with improvements over standard cine imaging practices. In essence, incorporating dynamic imaging data and pursuing temporal strain tracking could broaden the clinical relevance of regional strain markers and thus improve diagnostic capabilities and treatment planning.