What maneuvers can be performed to convert a patient with atrial flutter (AF) and rapid ventricular response (RVR) back to normal sinus rhythm?

From the Guidelines

To convert a patient with atrial flutter and rapid ventricular response back to normal sinus rhythm, synchronized cardioversion is the recommended approach, especially in hemodynamically unstable patients or those who do not respond to pharmacological therapies 1. When considering conversion, several factors must be taken into account, including the patient's hemodynamic stability, anticoagulation status, and the presence of any underlying heart disease.

• For patients who are hemodynamically stable, elective synchronized cardioversion can be indicated as part of a rhythm-control strategy, with the added benefit of potentially avoiding tachycardia-mediated cardiomyopathy 1.
• Pharmacological cardioversion using medications such as ibutilide or dofetilide can also be effective, especially when sedation is not available or not well tolerated, or based on patient preference, with ibutilide converting atrial flutter to sinus rhythm in approximately 60% of cases 1.
• Rate control using beta blockers, diltiazem, or verapamil is useful for acute rate control in hemodynamically stable patients, with intravenous diltiazem being the preferred calcium channel blocker due to its safety and efficacy 1.
• For patients with pacing wires in place, rapid atrial pacing can be a useful method for acute conversion of atrial flutter, effective in terminating flutter in more than 50% of cases 1.
• Vagal maneuvers, while not typically effective for rhythm conversion, can temporarily help control ventricular rate by increasing parasympathetic tone and slowing conduction through the AV node. It's crucial to assess anticoagulation status before any conversion attempt, especially if atrial flutter has lasted more than 48 hours, to mitigate the risk of stroke. The choice of maneuver depends on the individual patient's clinical presentation, underlying conditions, and preferences, with the goal of restoring normal sinus rhythm to improve morbidity, mortality, and quality of life outcomes.

From the FDA Drug Label

Patients with atrial flutter, 53% receiving 1 mg ibutilide fumarate and 70% receiving 2 mg ibutilide fumarate converted, compared to 18% of those receiving sotalol Among patients with atrial flutter, conversion rates at 1.5 hours were: placebo, 4%; 0.25 mg ibutilide fumarate, 56%; 0.5 mg ibutilide fumarate, 61%; and 1 mg ibutilide fumarate, 78% The majority of patients (53% and 72% in the 0.5 mg and 1 mg dose groups, respectively) converted to sinus rhythm remained in sinus rhythm for 24 hours

Maneuvers to convert atrial flutter with RVR to normal sinus rhythm include:

• Administration of ibutilide fumarate injection, with conversion rates ranging from 53% to 78% in clinical trials 2
• The use of other antiarrhythmic drugs, such as sotalol, although ibutilide fumarate was more effective in clinical trials 2
• Electrical cardioversion, which was allowed 90 minutes after the infusion was complete in clinical trials 2 Key considerations:
• Ibutilide fumarate is more effective in patients with atrial flutter than atrial fibrillation 2
• Patients with more recent onset of arrhythmia had a higher rate of conversion 2

From the Research

Maneuvers to Convert Atrial Flutter with RVR to Normal Sinus Rhythm

To convert a patient with atrial flutter (AF) and rapid ventricular response (RVR) back to normal sinus rhythm, several maneuvers can be performed:

• Vagal maneuvers: Although vagal maneuvers are not typically associated with the conversion of atrial fibrillation to sinus rhythm, they can cause an increase in vagal tone, which may help slow down supraventricular tachycardia, including atrial flutter 3.
• Digital rectal exam: A digital rectal exam has been shown to convert atrial fibrillation to sinus rhythm in one reported case, suggesting it may be considered as an additional attempt to convert AF to sinus rhythm in some patients 3.
• Pharmacological cardioversion: Various antiarrhythmic drugs, such as ibutilide, propafenone, dofetilide, and sotalol, have been shown to be effective in converting atrial flutter to sinus rhythm 4.
• Electrical cardioversion: Electrical cardioversion is a highly effective method for converting atrial flutter to sinus rhythm, with reported success rates of 97.9% to 100% 4.

Predictors of Spontaneous Conversion

Some patients with atrial flutter may spontaneously convert to normal sinus rhythm:

• Presentation with symptoms of <24-h duration is a predictor of spontaneous conversion 5.
• Normal left ventricular systolic function is more common among patients with spontaneous conversion, but it is not an independent predictor of conversion 5.

Additional Considerations

Cardioversion of atrial fibrillation or atrial flutter into sinus rhythm can also have benefits beyond converting the arrhythmia:

• Reduction in nocturnal central respiratory events and unmasking of obstructive sleep apnea 6.