During ventricular fibrillation, extra feedback may form in the myocardial structure due to specific features of such fibrillation, specifically, because of highly asynchronous contractions of some parts of the myocardium; these newly forming feedback is conducive to a persistent development of such arrhythmia. The frequency of the waves of mechanical contractions in various segments of the myocardium varies depending on the increase of hypoxia. The waves do not correlate with each other as regards their shape, neither do they correlate with the electrical activity waves. This indicates the complex nature of the mechanisms giving rise to and maintaining ventricular fibrillation. Study of the electromechanical correlations in the myocardium, observed in ventricular fibrillation, and analysis thereof together with the complex staged development of ventricular fibrillation may help better understand the pathological processes in the myocardium and, hence, enable us to develop effective methods to control it.