Therapeutic Range of Digoxin's Efficacy in Heart Failure: What Is the Evidence?

Abstract

Clinical studies have solidified the utility of digoxin in patients with left ventricular dysfunction and normal sinus rhythm. No definitive data have been published to clarify the range of serum digoxin concentrations associated with clinical benefit. The traditional therapeutic range of 0.8-2.0 ng/ml was developed originally to classify digoxin toxicity, not efficacy. In addition, this reference range was used before publication of the Digitalis Investigators Group trial. Clinical and neurohormonal studies have attempted to characterize serum concentrations that are associated with clinical efficacy.

Association of Serum Digoxin Concentration and Outcomes in Patients With Heart Failure

“…5,25,26 Thus, our findings are consistent with the hypothesis that digoxin provides a neurohormonal benefit with minimal inotropic-associated risk at lower SDCs. 3,20,21,25,26 As the SDC increases, the inotropic action of digoxin becomes stronger and begins to offset the therapeutic benefits provided by neurohormonal modulation and may account for The figure presents the crude all-cause mortality rate with 95% confidence intervals and the risk-adjusted rate for patients assigned to digoxin according to their serum digoxin concentration. The mortality rate in patients assigned to placebo is presented for comparison.…”

Therapeutic Ranges of Serum Digoxin Concentrations in Patients With Heart Failure

“…However, this explanation is, at best, only partly explanatory because articles in nonspecialty journals have critically reviewed currently accepted SDCs and strongly encouraged the adoption of more appropriate (lower) serum reference ranges for the previous decade or so. 36,37 …”

Evidence Based Digoxin Therapeutic Monitoring - A Lower and Narrower Therapeutic Range

“…The target serum digoxin concentration should be 0.5 to 1.0 ng/mL (0.6 to 1.3 nmol/L). Evidence rating is at B level (inconsistent or limited-quality patient-oriented evidence) [16,20,30].…”