Adenosine Use in Wolff-Parkinson-White Syndrome

Primary Recommendations

The American Heart Association recommends that adenosine should be used with extreme caution in WPW syndrome and is contraindicated in patients with pre-excited atrial fibrillation, as it can precipitate life-threatening ventricular fibrillation by triggering atrial fibrillation with rapid ventricular rates through the accessory pathway 1, 2
The European Society of Cardiology states that adenosine is the preferred agent for acute termination of regular, narrow-complex supraventricular tachycardia in hemodynamically stable WPW patients, as this indicates anterograde conduction is occurring through the AV node rather than the accessory pathway 3, 2

Adenosine terminates approximately 95% of orthodromic AVRT cases by blocking AV nodal conduction, according to the American College of Cardiology 4
The administration of adenosine involves a 6 mg IV push via large proximal vein followed immediately by 20 mL saline flush; if no conversion in 1-2 minutes, give 12 mg IV push, as recommended by the European Heart Rhythm Association 4
A defibrillator must be immediately available when administering adenosine to any patient with known or suspected WPW due to the risk of precipitating rapid atrial fibrillation, as stated by the American Heart Association 4

Adenosine is contraindicated when the QRS complex is wide (≥120 ms) during tachycardia, as this indicates anterograde conduction through the accessory pathway, according to the European Society of Cardiology 1, 2
For wide-complex tachycardia in WPW, the American College of Cardiology recommends using procainamide, ibutilide, or flecainide instead, which slow conduction through the accessory pathway 1, 2
Immediate electrical cardioversion is mandatory for pre-excited AF with hemodynamic instability rather than any pharmacologic agent, as stated by the European Heart Rhythm Association 2, 5

The American Heart Association recommends assessing QRS width during tachycardia and using adenosine only for narrow-complex tachycardia, with a QRS width of less than 120 ms 3, 2
Catheter ablation remains the first-line definitive treatment for symptomatic WPW patients, with success rates exceeding 95% and complication rates under 1-2% in experienced centers, according to the European Society of Cardiology 5, 2