Arrhythmia Management

Assessment and Initial Management

The American Heart Association and American College of Cardiology recommend assessing hemodynamic stability in patients with atrial flutter or AV block, and if unstable, immediate synchronized cardioversion with 50-100 joules should be performed, with a success rate approaching 95-100% 1, 2, 3, 4
For stable patients, medical management, including rate control with IV beta-blockers (e.g., metoprolol, esmolol) or non-dihydropyridine calcium channel blockers (e.g., diltiazem, verapamil), is recommended, with a target heart rate of initially <110 bpm 2, 3, 4
The European Society of Cardiology suggests that when using Class IC antiarrhythmic drugs, AV nodal blocking agents should always be co-administered to prevent 1:1 conduction 5, 6

The American Heart Association recommends targeting a heart rate initially <110 bpm for rate control in atrial flutter 2, 3, 4
Chemical cardioversion with IV ibutilide (70% success) or oral dofetilide (effective but carries a risk of torsades de pointes, 1.5-3%) can be effective for rhythm control 2, 1
Electrical cardioversion is more effective than pharmacological cardioversion, with success rates >95% 1, 2
Atrial overdrive pacing has a success rate of approximately 82% and is particularly useful in post-cardiac surgery patients with epicardial wires 1

The American College of Cardiology recommends anticoagulation for 3 weeks before and 4 weeks after cardioversion if the duration of atrial flutter is ≥48 hours or unknown, with options including warfarin (INR 2.0-3.0) or direct oral anticoagulants 2, 3
For atrial flutter <48 hours, cardioversion can be performed without prior anticoagulation, but anticoagulation should be started at presentation 1, 3
The American College of Cardiology recommends assessing the need for long-term anticoagulation based on the CHA₂DS₂-VASc score, with guidance from the European Society of Cardiology 7
For complete AV block, the European Heart Rhythm Association recommends evaluating for permanent pacemaker placement, and temporary transcutaneous or transvenous pacing can be used for hemodynamically significant bradycardia in symptomatic AV block 6, 1

The American College of Cardiology advises avoiding AV nodal blocking agents in patients with pre-excitation syndromes (e.g., WPW syndrome) as they may accelerate ventricular rate and precipitate ventricular fibrillation 3, 6
The European Society of Cardiology recommends avoiding non-dihydropyridine calcium channel antagonists in patients with decompensated heart failure as they may worsen hemodynamic status 3
The European Society of Cardiology recommends considering IV amiodarone for patients with severely depressed left ventricular ejection fraction (LVEF) 4
Atrial flutter with varying AV block can result in an irregular rhythm mimicking atrial fibrillation, highlighting the importance of careful ECG analysis 1