MECHANICS OF THE LEFT VENTRICLE: EFFECTS OF RADIAL ACTIVATION AND TWISTING MOTION.

The mechanical effects resulting from the normal transmural delay of electrical depolarization of the myocardium and from the application of an externally applied moment that presents left ventricle torsion are investigated. An activation sequence having a finite radial propagation velocity from endocardium to epicardium is introduced into the equations of ventricular mechanics. The resulting equilibrium system of coupled integral equations is solved using a perturbation method based on the small ratio of transmural propagation time to cardiac period. Numerical results are presented and analyzed.