[The dynamics of the form of the extracellular potentials and of the process of depolarization wave spreading in the intramural layers of the myocardium in dogs with experimental ischemia].

The reversal of directions and local delays or accelerations of the extracellular potentials evolution occurred at arrival of the depolarization wave after coronary occlusion in dogs. General patterns of directions of the activation spread changed relatively little when compared to normal. Apparently, in spite of the ligation of the left anterior descending coronary artery, ischemia was not achieved. There was some additional blood supply to the ischemic myocardium from deep collateral arterial branches. Therefore, the observed abnormalities of electrical potentials and the reversals of the depolarization wave direction only took place in local small zones of ischemic myocardium.