Evaluation of left ventricular function using left ventricular twist and torsion parameters.

Masaaki Takeuchi1, Yutaka Otsuji, Roberto M Lang

  • 1Second Department of Internal Medicine, University of Occupational and Environmental Health, School of Medicine, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan. takeuchi@med.uoeh-u.ac.jp

Summary

Left ventricular twist, a key heart function, can now be measured noninvasively using 2D speckle tracking echocardiography. This technique offers a practical approach to assessing heart mechanics and clinical function.

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Pre-Procedural Preparation
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In materials that exhibit elastic and plastic behavior, known as elastoplastic materials, residual stresses can accumulate when these materials experience plastic deformation. This deformation arises from either high levels of shearing stress or significant strains. Residual stresses are internal stresses that persist within a material after removing the external force causing deformation. This phenomenon is demonstrated when observing the behavior of a shaft under torque; notably, the shaft's...
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