We conducted a thorough search of databases such as PubMed, Google Scholar, and Cochrane Library, from inception until 20th Aug 2023. Studies that explored the relationship between serum digoxin concentration and mortality, morbidity, or other clinical endpoints in AF and HFrEF patients (ejection fraction ≤45 %) were eligible for inclusion.

The selected studies exhibited a wide range of designs, patient cohorts, and measured outcomes. The association between serum digoxin concentration, mortality and morbidity endpoints like hospitalization rates and cardiovascular events were assessed in these studies. Despite the methodological diversity, our systematic review uncovered consistent trends across the studies, suggesting that elevated serum digoxin concentrations may correlate with higher mortality and morbidity in AF and HFrEF patients.

This systematic review emphasizes the need for cautious management of serum digoxin levels in patients with concurrent AF and HFrEF. While digoxin remains a valuable treatment for heart failure, its potential adverse effects on outcomes in this specific patient subgroup call for vigilant monitoring and individualized treatment approaches. Further research is required to elucidate the dose-response relationship and potential confounding factors influencing outcomes associated with serum digoxin concentration in AF and HFrEF patients. Clinicians should consider these findings when making therapeutic decisions to enhance patient care and outcomes.