The present work is aimed at investigating the effects of myocardial infarction and ischemia on induction of ventricular fibrillation. Electrophysiologic effects of global and local ischemia (variation of the dispersion of refractory periods as well as conduction velocity) on initiation of reentry mechanisms was studied by means of computer simulations based on a cellular automata model of propagation of activation wave through a ventricular surface element. A local area of ischemia where effects of the dispersion of refractory periods are investigated (...) is then simulated. This is made using a Gaussian distribution characterized by its mean and standard deviation. These simulations show that ischemia is capable of initiating reentry phenomena which propagate through the whole ventricle; they are responsible for ventricular fibrillation which causes sudden cardiac death, even when ischemia only involves limited parts of the myocardium. Statistical study of the probability of reentries as a function of both of the size of ischemic zones and the rate of dispersion of refractory periods shows that the latter parameter is of primary importance in triggering cardiac reentries. (shrink)

En hommage à Violaine Houdart-Merot, cet ouvrage rassemble des textes qui convergent vers une approche vivante de la littérature où l'esthétique du divers apparaît orientée par une logique de recherche, mais aussi par la ligne de force d'une réflexivité commune sur la nature des Humanités contemporaines. Ces contributions donnent ainsi le ton d'une ultime réconciliation des Anciens et des Modernes et signent l'entrée dans une ère où la considération du littéraire accepte l'expérimentation créative.