[Effect of N-propylajmaline bromide on the normal and abnormal automatism of Purkinje fibers in the dog].

The effects of prajmalium bromide on normal and abnormal automaticity were studied in Purkinje fibers from dog hearts at late stages of experimental myocardial infarction. Prajmalium bromide (1.2 micromol/l) moderately reduced the frequency of normal and abnormal automaticity by 16 and 20% respectively. Prajmalium bromide induced early after-depolarizations, increased the frequency of spontaneous firing and decreased the maximum diastolic potential in the fibers that initially developed the automaticity of an intermediate type between normal and abnormal. It is suggested that antiarrhythmic effects of prajmalium bromide in the late stage of experimental myocardial infarction are not related to the influence of the drug on the abnormal automaticity in Purkinje fibers.