The individual myofibers around in sheets comprised of multiple layers

The individual myofibers around in sheets comprised of multiple layers, in a rotating orientation (see figure 3). Throughout the layers of heart wall, the fibre direction is not uniform. It changes from longitudinal to circumferential and then towards the longitudinal direction again (14).
Myocytes form parallel sheets in line with the epicardial surface of the heart. Here, the myocytes align at a negative angle with respect to the circumferential axis, with the amount of rotation varying throughout the LV (14, 15). Conversely, the myocytes nearest the endocardial surface align in a positive direction.
This configuration provides the myocardium with strength in the longitudinal and circumferential direction. These directions experience the highest stresses throughout contraction. The arrangement of the myocytes in this way results in the generation of ventricular torsion when the myocytes contract and relax (16).