Morphological and functional evidences of the helical heart from non-invasive cardiac imaging.

The non-invasive study of cardiac mechanics has been improved after the recent introduction of advanced magnetic resonance and echocardiographic imaging techniques. Tagged and diffusion-sensitive cardiac magnetic resonance allows the study of myocardial torsion dynamics as well as the anatomical disposition of myocardial fibers. Local myocardial strain and synchronicity of myocardial contraction can also be determined with Doppler tissue imaging (DTI) echocardiography. Published results with these techniques demonstrate a mechanical behavior that is a consequence of a myocardial helical fiber orientation and strongly support the evidence of the double-loop single muscular band model described by Torrent-Guasp.