Impact of Digoxin Use on Guideline-Directed Medical Therapy in Patients With Heart Failure With Reduced Ejection Fraction

BACKGROUND: Digoxin was one of the first agents used in the management of heart failure with reduced ejection fraction (HFrEF). Concerns over its safety, efficacy, and the introduction of guideline-directed medical therapy (GDMT) have relegated it to a secondary role. The efficacy of digoxin is still under debate, and its use in patients on GDMT remains unclear. We aim to evaluate whether patients with HFrEF on digoxin can tolerate higher doses of a β-blocker (BB), angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blocker (ARB), mineralocorticoid receptor antagonists (MRAs), and angiotensin receptor-neprilysin inhibitor (ARNI). METHODS: A retrospective chart review was performed on 233 patients with HFrEF managed at a tertiary care center in Cleveland, Ohio. A bivariate analysis was performed to compare patients on digoxin with patients not on digoxin in terms of ability to progress the dosing of BB, ACEI, MRA, ARB, or ARNI. RESULTS: Thirty-four (14.6%) of our 233 patients were receiving digoxin at baseline visit. The digoxin group was more likely to have lower initial and last systolic blood pressure, initial diastolic blood pressure, and left ventricular ejection fraction. Mean follow-up duration and baseline sodium level were higher in the digoxin group. There was no significant difference between the two groups in terms of patients receiving higher doses of BB (P = 0.235), ACEI/ARB (P = 0.903), MRA (P = 0.331), or ARNI (P = 0.717). CONCLUSIONS: There was no significant difference between the doses of BB, ACEI, ARB, MRA, or ARNI among HFrEF patients on digoxin compared to those that were not. Randomized control trials with a larger sample are needed to establish our findings of digoxin not significantly affecting the ability to up titrate GDMT in HFrEF patients.