The Effect of Acute Digitalization on the Hemodvnamic Response to Exercise in Coronary Artery Disease

Hemodynamic observations are made at rest and during exercise before and follow-ing the administration of 0.5 mg of ouabain in patients with coronary artery disease and in normal subjects. Patients with coronary artery disease and exertional angina showed evidence of reversible cardiac failure during exercise. The patients with cor-onary artery disease who did not have angina and the normal subjects had normal hemodynamic responses to exercise. Acute digitalization did not prevent angina in any of the symptomatic patients, although there was hemodynamic evidence of improved ventricular performance. In the patients with coronary disease without angina minor hemodynamic changes at rest and during exercise were suggestive of improved left ventricular function. Additional Indexing Words: Digitalis glycosides Ventr Left ventricular end-diastolic pressure ricular failure Ventricular functi Myocardial ischemia on HEMODYNAMIC STUDIES during acute coronary insufficiency occurring either spontaneously " 2 or precipitated by exer-cise, " 3 isoproterenol,5 or atrial pacing'0-'3 have shown depression of left ventricular function. The elevated left ventricular end-diastolic pressure found during exertional an-gina3 ' 6-fl has been considered to be due to altered left ventricular compliance,9 but a more likely explanation is reversible left ven-tricular failure.12 The occurrence of hemodynamic changes suggestive of left ventricular failure during ex-ercise in patients with coronary artery disease has led to limited investigation of the effect of digitalis on the hemodynamic response to ex-ercise and on exercise tolerance. Malmborg4 found that exertional angina was prevented i