Overview
Clinical Meaning
Digoxin is a cardiac glycoside with two clinically useful effects: it increases myocardial contractility and slows conduction through the atrioventricular (AV) node.
Digoxin is a cardiac glycoside with two clinically useful effects: it increases myocardial contractility and slows conduction through the atrioventricular (AV) node. In selected adults with mild-to-moderate chronic heart failure, stronger contraction can improve symptoms and functional status. In chronic atrial fibrillation, increased vagal tone slows AV-node conduction and can reduce the ventricular rate. Pediatric heart-failure patients may also receive digoxin to increase contractility. Its benefits come with a narrow therapeutic window. The same mechanism that slows AV conduction can produce bradycardia or heart block when exposure becomes excessive, while increased intracellular calcium can promote dangerous ventricular irritability. Digoxin toxicity therefore does not have one single rhythm pattern. A patient may develop a slow pulse, ventricular ectopy, AV block, ventricular tachycardia, or more than one rhythm abnormality over time. The mechanism explains why the nurse must connect the medication history with the patient’s renal function, electrolytes, symptoms, and ECG. A new nausea complaint in a patient taking digoxin is not automatically a gastrointestinal problem. If it occurs with yellow-green visual halos, confusion, a rising creatinine, or a new rhythm change,...