Some effects of digoxin on the heart and circulation in man; digoxin in enlarged hearts not in clinical congestive failure.

The early effect of intravenous Digoxin was observed in 12 patients with cardiac enlargement in whom there was no clinical or physiologic evidence of failure. There was either a fall or no change in the cardiac output and the intracardiac pressures did not alter following administration of the drug. The reaction to Digoxin in this type of patient with heart disease was in no way different from the response seen in two normal subjects included in the study but is in sharp contrast to the response elicited in patients in congestive heart failure. P REVIOUS reports have been published on the effects of intravenous Digoxin in left ventricular failure' and iight heart failure2 and these studies have indicated that the failing heart responds with an increase in cardiac output. This effect has been attributed to a myocardial action of the drug. The present study has been undertaken to determine the drug action in patients with enlarged , and hence abnormal, hearts who had no evidence, either clinical or physiologic, of con-gestive cardiac failure. In considering the e-sults, interest has been centered about. twno main problems; first, how does the reaction of the enlarged heart to acute digitalization differ from that of the enlarged and decoInpensated heart and second, what information can be obtained about the circulatory dynamics in the former group of patients. The reaction to D)igoxin in 2 individuals without any evi(lence of heart disease is included in this study for comparison, as is the effect of the drug in one patient in congestive failure. The work described in this paper was supported by, a grant from the Life Insurance Medical Research Fund, with additional support provided b)y the Commonwealth Fund. 366 MATERIAL AND METHODS The 12 patients with enlarged hearts include 2 with hypertensive cardiovascular disease, 5 with arteriosclerotic heart disease, one with syphilitic and 3 with rheumatic heart disease, and one with an unknown variety of heart disease. The criteria used for diagnosis were these of the New York Heart Association. The functional and therapeutic classification represents the status of the patient at the time of the study. The details of the diagnoses can be found in table 1. It should be noted that 3 of the 12 patients had had a recent episode of cardiac failure. In 2 this appeared to be left heart de-canipensation (cases 391 and 418) while in the third patient (case 552) …