Regional assessment of left ventricular torsion by CMR tagging

• Published in: Journal of cardiovascular magnetic resonance Vol. 10; no. 1; p. 26
• Main Authors: Rüssel, Iris K, Götte, Marco J, Kuijer, Joost P, Marcus, J Tim
• Format: Journal Article
• Language: English
• Published: London BioMed Central 27.05.2008; BioMed Central Ltd; Elsevier
• Subjects: Adult; Angiology; Cardiology; Diagnosis; Female; Heart diseases; Heart Ventricles - anatomy & histology; Humans; Imaging; Magnetic resonance; Magnetic Resonance Imaging, Cine; Male; Medicine; Medicine & Public Health; Middle Aged; Models, Anatomic; Radiology; Torsion, Mechanical; Ventricular Function, Left; Netherlands; Right Ventricle; Aortic Valve Closure; Diffusion Tensor Imaging Fiber Tracking; Analytical Test Case; Left Ventricular Rotation
• ISSN: 1097-6647; 1532-429X; 1532-429X
• DOI: 10.1186/1532-429X-10-26

Purpose To introduce a standardized method for calculation of left ventricular torsion by CMR tagging and to determine the accuracy of torsion analysis in regions using an analytical model. Methods Torsion between base and apex, base and mid, and mid and apex levels was calculated using CSPAMM tagging and Harmonic Phase tracking. The accuracy of torsion analysis on a regional basis (circumferential segments and transmural layers) was analyzed using an analytical model of a deforming cylinder with a displaced axis of rotation (AoR). Regional peak torsion values from twelve healthy volunteers calculated by the described method were compared to literature. Results The deviation from the analytical torsion per % AoR-displacement (of the radius) was 0.90 ± 0.44% for the circumferential segments and only 0.05% for the transmural layers. In the subjects, circumferentially, anterolateral torsion was larger than inferior (12.4 ± 3.9° vs. 5.0 ± 3.3°, N.S.). Transmurally, endocardial torsion was smaller than epicardial (7.5 ± 1.3° vs. 8.0 ± 1.5°, p < 0.001). Conclusion Variability in the position of the AoR causes a large variability in torsion in circumferential segments. This effect was negligible for global torsion, and torsion calculated in transmural layers. Results were documented for the healthy human heart and are in agreement with data from literature.