What is the first-line treatment for a patient presenting to the emergency room with atrial fibrillation and rapid ventricular response (tachycardia)?

From the Guidelines

The first-line treatment for a patient presenting to the emergency room with atrial fibrillation and rapid ventricular response (tachycardia) is rate control with intravenous beta-blockers or calcium channel blockers.

Key Considerations

• The primary goal is to control the ventricular rate and reduce symptoms, as stated in the 2024 ESC guidelines for the management of atrial fibrillation 1.
• Beta-blockers, such as metoprolol, and calcium channel blockers, such as diltiazem, are recommended as first-choice drugs for rate control in patients with AF and LVEF >40% 1.
• For patients with LVEF ≤40%, beta-blockers and/or digoxin are recommended for rate control 1.

Treatment Options

• Metoprolol 5-10 mg IV given slowly over 2-5 minutes, which can be repeated every 5-15 minutes up to a total of 15 mg, is commonly used.
• Diltiazem 0.25 mg/kg IV over 2 minutes (typically 15-20 mg), followed by a second dose of 0.35 mg/kg if needed after 15 minutes, is effective.
• For hemodynamically unstable patients, immediate electrical cardioversion with 120-200 joules is indicated instead.

Additional Recommendations

• Anticoagulation should also be initiated unless contraindicated, typically with heparin or low molecular weight heparin, followed by oral anticoagulants based on stroke risk assessment, as suggested by the 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation 1.
• The choice of treatment should be individualized based on patient symptoms, hemodynamics, and underlying cardiac function, as recommended by the 2010 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care 1.

From the FDA Drug Label

As with other agents which slow AV nodal conduction and do not prolong the refractoriness of the accessory pathway (e.g., verapamil, digoxin), in rare instances patients in atrial fibrillation or atrial flutter associated with an accessory bypass tract may experience a potentially life-threatening increase in heart rate accompanied by hypotension when treated with injectable forms of diltiazem Once familiarity of the patient's response is established, use in an office setting may be acceptable.

The first-line treatment for a patient presenting to the emergency room with atrial fibrillation and rapid ventricular response (tachycardia) is not explicitly stated in the provided drug labels. Key considerations for treatment include:

• The potential risks associated with using injectable forms of diltiazem in patients with atrial fibrillation or atrial flutter, particularly those with accessory bypass tracts.
• The need for careful patient selection and monitoring when using diltiazem in this setting 2.

From the Research

First-Line Treatment for Atrial Fibrillation with Rapid Ventricular Response

The first-line treatment for a patient presenting to the emergency room with atrial fibrillation and rapid ventricular response (tachycardia) involves rate or rhythm control.

• Rate control can be achieved using beta blockers or calcium channel blockers, as stated in the study 3.
• The choice between beta blockers and calcium channel blockers may depend on the patient's specific condition, such as the presence of heart failure.
• A study comparing intravenous metoprolol and diltiazem for rate control in atrial fibrillation found no significant difference in the achievement of rate control between the two medications 4.
• However, another study found that diltiazem reduced heart rate more quickly and resulted in greater heart rate reductions than metoprolol in patients with atrial fibrillation and concomitant heart failure 5.

Considerations for Patients with Heart Failure

• In patients with heart failure with reduced ejection fraction (HFrEF), the use of calcium channel blockers such as diltiazem may be avoided due to their potential negative inotropic effects, as noted by the American Heart Association.
• However, a study found that the incidence of adverse effects was similar between diltiazem and metoprolol in HFrEF patients with atrial fibrillation, although the diltiazem group had a higher incidence of worsening heart failure symptoms 6.
• Another study found that diltiazem was effective in controlling heart rate in patients with atrial fibrillation and concomitant heart failure, with no significant difference in safety outcomes compared to metoprolol 5.

Emergency Department Management

• The management of atrial fibrillation with rapid ventricular response in the emergency department involves assessing the patient's hemodynamic stability and determining the appropriate treatment approach, as outlined in the study 3.
• Emergent cardioversion is indicated in hemodynamically unstable patients, while rate or rhythm control should be pursued in hemodynamically stable patients.
• The use of troponin testing and anticoagulation therapy should also be considered in the management of atrial fibrillation, as discussed in the study 3.