DIGITALIS AND EXPERIMENTAL MYOCARDIAL INFARCTION

Acetylstrophanthidin tolerance tests were carried out in a series of farm pigs in the conscious unrestrained state. Serial testing of these animals showed that the dose to produce cardiac arrhythmias, the duration of the arrhythmias, and the gastrointestinal toxic dose were predictable and stable measures. Three groups of animals were compared: a control group, a sham operated group, and a group who experienced gradual circumflex coronary occlusion and subsequent infarction. The experimental infarction was induced by an Ameroid constrictor. With this technique, it was possible to carry out serial observations of acetylstrophanthidin tolerance during the evolution of the infarction. The toxic dose, the duration and the arrhythmias, and the gastrointestinal intoxicating dose remained unchanged in the control and sham groups. In the 8 animals studied during the evolution of experimental myocardial infarction, the average intoxicating dose was reduced by approximately 1 3, the arrhythmias lasted twice as long and the usual pattern of cardiac intoxication preceding G1 symptoms was reversed. © 1969.