SHM Converge Scientific Abstract ePoster Gallery-Digoxin Toxicity: A Case for Not Checking Repeat Levels

Pdf Summary

This case describes an 83-year-old man with atrial fibrillation, severe congestive heart failure, and end-stage renal disease on hemodialysis who developed symptomatic bradycardia after continuing digoxin despite being told to stop it after a recent hospitalization. He presented with dizziness, weakness, dyspnea on exertion, a heart rate in the 30s, and an ECG showing idioventricular rhythm consistent with digoxin toxicity. His initial serum digoxin level was markedly elevated at 4.7 ng/mL, supporting the diagnosis.<br /><br />He was treated in the cardiac critical care unit with digoxin-specific antibody fragments (DSFab), temporary holding of metoprolol and amiodarone, hemodialysis, and continuous renal replacement therapy because of his renal failure and clinical status. A repeat digoxin level after DSFab was 7.2 ng/mL, illustrating that post-treatment levels can be falsely elevated because standard assays detect digoxin bound to DSFab. The patient’s bradycardia resolved by discharge, and he was instructed to permanently stop digoxin and restart metoprolol.<br /><br />The report emphasizes several teaching points: digoxin toxicity is primarily a clinical diagnosis, elevated levels before treatment can help confirm it, but repeat digoxin levels should not be checked after DSFab administration because they are misleading. Patients with end-stage renal disease are at higher risk for rebound toxicity due to DSFab-digoxin complex dissociation and require close monitoring. Dialysis is not a first-line treatment for digoxin toxicity because digoxin has a large volume of distribution, but it may be useful in patients with concurrent renal failure or electrolyte abnormalities.

Asset Subtitle

Prasanti Kotta

Meta Tag

Author List Maria Lee, Michelle Lee, Patrick T Lynch, Prasanti Kotta, Priscilla Liem

Category Clinical Vignettes

Concept Digoxin Toxicity

Concept Digoxin-Specific Antibody Fragments

Concept Clinical Diagnosis

Concept Digoxin Level

Concept False Elevation

Distinguished Non-Finalist

Presenter Organization Baylor College of Medicine

Presenting Author Prasanti Kotta

Track Adult

Keywords

digoxin toxicity

bradycardia

atrial fibrillation

end-stage renal disease

hemodialysis

digoxin-specific antibody fragments

idioventricular rhythm

serum digoxin level

cardiac critical care

renal failure

Digoxin Toxicity

Digoxin-Specific Antibody Fragments

Clinical Diagnosis

Digoxin Level

False Elevation