What are the preferred intravenous (IV) medications for atrial fibrillation (AFib) with rapid ventricular response (RVR)?

From the Guidelines

For atrial fibrillation with rapid ventricular response (AFib with RVR), the preferred IV medications include beta blockers, nondihydropyridine calcium channel antagonists, and amiodarone, with the choice depending on patient factors such as heart failure status and hemodynamic stability. The most recent and highest quality study 1 recommends the use of IV beta blockers or nondihydropyridine calcium channel antagonists to slow the ventricular response to AF in the acute setting, with caution needed in patients with overt congestion, hypotension, or heart failure with reduced left ventricular ejection fraction (LVEF). In patients with heart failure, IV digoxin or amiodarone is recommended to control heart rate acutely 1. The dosing for these medications can vary, but typical regimens include:

• Beta blockers such as metoprolol, administered as 5 mg IV boluses every 5 minutes for up to 3 doses (15 mg total)
• Nondihydropyridine calcium channel antagonists such as diltiazem, given as a 0.25 mg/kg IV bolus (usually 15-20 mg) over 2 minutes, followed by a continuous infusion of 5-15 mg/hour if needed
• Amiodarone, given as a 150 mg IV bolus over 10 minutes, followed by 1 mg/min for 6 hours, then 0.5 mg/min for 18 hours It is essential to continuously monitor cardiac function and blood pressure during administration, as these medications can cause hypotension, and to correct electrolyte abnormalities, particularly potassium and magnesium, to optimize treatment efficacy and reduce the risk of proarrhythmia. Key considerations in choosing between these agents include the presence of heart failure, hemodynamic stability, and potential contraindications such as bronchospasm or pre-excitation syndromes. Overall, the goal of treatment is to control the ventricular rate, reduce symptoms, and prevent complications such as heart failure or thromboembolism, while minimizing the risk of adverse effects.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION Direct Intravenous Single Injections (Bolus) The initial dose of diltiazem hydrochloride injection should be 0. 25 mg/kg actual body weight as a bolus administered over 2 minutes (20 mg is a reasonable dose for the average patient). Continuous Intravenous Infusion For continued reduction of the heart rate (up to 24 hours) in patients with atrial fibrillation or atrial flutter, an intravenous infusion of diltiazem hydrochloride injection or diltiazem hydrochloride for injection may be administered

The preferred intravenous (IV) medication for atrial fibrillation (AFib) with rapid ventricular response (RVR) is diltiazem (IV), with an initial dose of 0.25 mg/kg administered over 2 minutes, followed by a continuous infusion of 10 mg/h as needed, up to 15 mg/h for up to 24 hours 2.

• Key points:
  • Initial dose: 0.25 mg/kg IV bolus
  • Continuous infusion: 10 mg/h, adjustable up to 15 mg/h
  • Duration: up to 24 hours
• Note: The information provided is based on the dosage and administration guidelines for diltiazem (IV) and may not be applicable to other medications or patient populations.

From the Research

Preferred Intravenous Medications for Atrial Fibrillation with Rapid Ventricular Response

The following intravenous (IV) medications are preferred for managing atrial fibrillation (AFib) with rapid ventricular response (RVR):

• IV beta blockers, such as metoprolol 3, 4, 5, 6
• IV calcium channel blockers, such as diltiazem 3, 4, 7, 5, 6 and verapamil 5
• IV procainamide for ventricular preexcitation syndrome associated with rapid ventricular rate due to AFib 3

Considerations for Medication Selection

When selecting a medication, consider the following factors:

• Cardiovascular status and associated noncardiac clinical disorders 3
• Presence of concomitant left ventricular failure symptoms 4
• Presence of heart failure with reduced ejection fraction (HFrEF) 6
• Potential for adverse effects, such as hypotension, bradycardia, and worsening heart failure symptoms 6

Dosage and Administration

The dosage and administration of these medications may vary depending on the specific clinical context:

• IV diltiazem may be administered as a bolus or continuous infusion 7
• IV metoprolol may be administered as a bolus or continuous infusion 5, 6
• IV procainamide may be administered as a bolus or continuous infusion 3

Monitoring and Evaluation

Regular monitoring and evaluation are necessary to assess the effectiveness of treatment and potential adverse effects:

• Monitor heart rate and blood pressure closely after administration of IV medications 4, 7, 5, 6
• Evaluate the incidence of adverse effects, such as hypotension, bradycardia, and worsening heart failure symptoms 6
• Assess the need for additional medications or alternative treatments, such as cardioversion or radiofrequency ablation 3, 4