Action of prostaglandins on heart arrhythmias

Depending on the type applied, prostaglandins have different cardiovascular effects both with regard to blood pressure and inotropic action. Results from experiments on animals show that the antiarrhythmic effect seems to be relatively uniform. So far our own clinical investigations have been carried out on 18 patients with disturbances of the heart rhythm predominantly due to organic causes. The response to PGF2 alpha infusions in dosages of 0.5-3.0 mg was not uniform. At constant heart rates, transitory regression of distrubances in the heart rhythm occurred, most pronounced in ventricular extrasytoles. Positive results became particularly evident in patients suffering from myocardial infarction, partially coinciding with the administration of cardiac glycosides. The antiarrhythmic effects cannot be explained by non-specific quinidine-like actions which was also confirmed by the lacking prostaglandin action on the diastolic stimulus threshold.