This animation shows the dynamics of electrical waves both on the surface and inside ventricular tissue during simulated ventricular fibrillation in an otherwise healthy slab of heart tissue. Three-dimensional spiral waves of bioelectricity can be seen directly on the surfaces and also indirectly within the tissue as vortex lines that follow the path of the spiral tip through the tissue. The ends of the vortex lines can be located only along the boundary faces.

In this simulation, the initial three-dimensional spiral wave becomes more complex due to differences in wave speed relative to the orientation of cardiac muscle fibers. Waves propagate about three times faster along cardiac fibers than across fibers. The fibers are oriented roughly parallel to the top and bottom surfaces, with a primary axis that rotates 120 degrees over the depth.

To begin the animation, press Start. Checking the Loop box allows the animation to replay continuously. Different views can be selected from the list at the left. The top surface is transparent while the bottom surface is opaque. Checking the Rotate(z) box causes the animation to rotate continuously while the animation plays. The slab also can be rotated, zoomed, or panned directly using the mouse.

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Fenton FH, Cherry EM, Hastings HM, Evans SJ. Multiple mechansims of spiral wave breakup in a model of cardiac electrical activity. Chaos 2002; 12: 852-892.