Effects of physical exercise and glibenclamide on local activation waves during Ventricular Fibrillation

This study is aimed at characterizing cardiac mapping recordings during Ventricular Fibrillation (VF) according to the fragmentation level and occurrence ratio of its Local Activation Waves (LAWs), in order to analyse the effects of physical exercise in the electrical activity of VF, compared to the effects of Glibenclamide drug. Three groups of rabbits were used. G 1: control (sedentary rabbits), G2: trained (rabbits under a running program) and G 3: drugged (sedentary rabbits treated with Glibenclamide). VF was induced during each experiment, and two recordings were acquired: maintained perfusion and ischemic damage. LA Ws were detected using the maximal derivative and were classified according to its fragmentation. The complexity level was measured with the Fractionated LA W Ratio (FLR). Finally, the activation rate was quantified using the LA Ws Occurrence Rate (LOR). The temporal evolution of FLR showed that, with maintained perfusion or ischemic damage, the trained group has the lowest values, and no diferences were found between drugged and control groups. Regarding LOR, the results depend on the perfusion conditions. When perfusion is maintained, drugged group has the lowest values (p<;O.05). On the contrary, when there is ischemic damage, drugged group has the highest LOR values (p<;O.05). No significant diferences were found between LOR of control and trained groups. Obtained results show that physical exercise and Glibenclamide modifY LA Ws properties. Physical exercise reduces its fragmentation, decreasing the complexity of LA Ws. In contrast, Glibenclamide modifies the activation interval, related to speed of fibrillation.