Post-repolarization refractoriness in the ventricular muscle

The authors extend an experimental model to a two-dimensional analysis of post-repolarization refractoriness (PRR) and ventricular arrhythmias. The rectifying potassium channel in the plateau phase of the model plays a major role in the near-synchronous repolarization in the normal tissue. With changes in the time constant of inactivation of inward currents and with the concentration changes in calcium and potassium ion, the action potential duration can be seen to be affected adversely. This, coupled with the poor cellular communication observed, affects the slow recovery of subthreshold currents, leading to PRR