Modifications in the activation process during ventricular fibrillation by local hyperthermia

Because of its electrophysiological effects, temperature can influence ´the mechanisms of the ventricular fibrillation (VF). The aim of this work was to investigate, in experimental models, the effects of local hyperrhenniu on the activation frequency during VF, and its hypothetic influence on distant zones. The application of hyperthermia on a limired area of the epicardium was performed by a specijic multielectrode-device. based on thick-film technology and Peltier efect. A significant increase in the Dominant Frequency of the VF signal (DF) in the modiped area was observed. Otherwise. the relative increments of DF in this zone and in the normothermic one, were correlated. In the model used, the effects of heating remitted afrer temperature returned to control value. Our results suggest that the activation process during VF is accelerated, in a reversible manner, by local hyperthermia, and this effect could affect normothermic zones.