Effect of Mechanical Stretching of the Right Atrium of Isolated Rat Heart on Dispersion of Repolarization before Fibrillation.

The multi-electrode mapping method was used to analyze electrical activity of isolated rat heart under conditions of standard perfusion, pharmacological stimulation of fibrillation, and mechanical stretching of the right atrium both under normal conditions and before cardiac fibrillation. It was shown that stretching of the right atrium prevented the increase of repolarization dispersion and latency of the electrical signal in the myocardium that were observed before cardiac fibrillation.