The available experimental and clinical data still leave many unanswered questions concerning the role of digitalis therapy after acute myocardial infarction. It seems clear that little is to be gained by glycoside administration to patients with uncomplicated infarctions who do not have cardiomegaly. The precise role of digitalis therapy in the treatment of cardiogenic shock remains undefined on the basis of the available data. However, until evidence to the contrary appears, its use should be continued on the basis of experience with experimental cardiogenic shock and the presumption that this state, when observed clinically, is a form of extreme left ventricular failure.Digitalis appears to be indicated in the treatment of atrial fibrillation with rapid ventricular rate complicating acute myocardial infarction. Other supraventricular arrhythmias, such as atrial flutter and ectopic atrial tachycardia, frequently require larger doses of the glycoside, and other means of therapy, such as antiarrhythmic agents or electrical conversion, may be preferable in such instances.Digitalis is commonly utilized early in the treatment of congestive heart failure and cardiomegaly complicating acute myocardial infarction, despite the paucity of experimental and clinical evidence in support of such therapy. Whether the digitalis glycosides should continue to be used routinely in such patients is an important subject for clinical investigation.