[Role of electrical interference between adjacent portions of the myocardium in the origin of arrhythmias].

Excitation propagation was studied in the papillary muscle of cat's heart and on a mathematical model of homogenous fibre, considerable inhomogeneity being created in the duration of the action potential (DAP) in the left and right part of the object studied. Gradual changes in DAP were observed during excitation propagation period, therefore rough differences in DAP of neighbouring myocardial areas may be excluded. No arrhythmia was observed. It is shwon that the arrhythmia which occurred previously [7] with an increase of DAP in one part of the preparation after EDTA addition was not connected with DAP differences in the neighbouring myocardial areas.