A Recognition of Digitalis Intoxication in the Presence of Atrial Fibrillation

In the presence of atrial fibrillation, digitalis toxicity can produce A-V nodal escape rhythm or non-paroxysmal A-V nodal tachycardia, and both of these are characterized by a regular ventricular rhythm. Non-paroxysmal A-V nodal tachycardia with exit block or the intermittent appearance of A-V nodal tachycardia, A-V nodal escape rhythm or ventricular premature contractions can produce an irregular rhythm which simulates uncomplicated atrial fibrillation. These digitalis-induced arrhythmias are not frequently associated with gastrointestinal symptoms and therefore an electrocardiogram is essential for diagnosis.