Hemodynamic effects of digoxin on congestive heart failure

To assess the hemodynamic effects of digoxin (0.01 mg/kg) on congestive heart failure, we evaluated 19 patients with decreased contraction force of left ventricle (old myocardial infarction n = 9, and dilated cardiomyopathy n = 10, group 1) and 8 patients with mechanical impaired left ventricular filing (mitral stenosis n = 8, group 2). In groups 1 and 2, heart rate and pulmonary capillary pressure significantly decreased (p less than 0.05). In group 1, stroke volume increased, but not significantly. In group 2, stroke volume increased significantly (p less than 0.05). There were no significant changes in blood pressure and systemic vascular resistance in either group. We divided group 1 into two groups (group 1A: cardiac index increased more than 15%, group 1B: cardiac index increased less than 15%). In group 1A, cardiac index and % fractional shortening before digoxin administration were lower than in group 1B (1.97 + 0.27 vs 2.80 + 0.481/min/m2, p less than 0.001, and 10.9 + 8.0 vs. 19.5 +11.9%, p less than 0.05, respectively). These data suggested that digoxin exerted a positive inotropic effect with decreased pulmonary capillary pressure but cardiac index did not always increase in congestive heart failure.