Related Experiment Videos
Role of calcium antagonists for heart rate control in atrial fibrillation
1Department of Medicine, Medical College of Virginia, Richmond.
Insights
Rapid heart rate control in atrial fibrillation is crucial. New intravenous calcium antagonist infusions offer sustained and effective management, improving upon older methods like digoxin and beta blockers.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Atrial fibrillation is a common arrhythmia causing symptoms, especially with rapid ventricular rates (>120 bpm).
- Intravenous digoxin and beta-blockers have limitations including ineffectiveness, toxicity, and hypotension.
- Current bolus administration of calcium antagonists like diltiazem or verapamil has short duration and limits fine-tuning of heart rate.
Purpose of the Study:
- To evaluate the effectiveness of new intravenous calcium antagonist infusion techniques for controlling ventricular rate in atrial fibrillation.
- To compare the sustained control offered by infusion techniques versus traditional bolus methods.
Main Methods:
- Review of recent studies on intravenous calcium antagonist administration for atrial arrhythmias.
- Focus on bolus plus maintenance infusion techniques with diltiazem.
Main Results:
- Intravenous calcium antagonists, particularly diltiazem, show promise in acute rate control.
- A novel bolus plus maintenance infusion technique with diltiazem demonstrates potential for sustained heart rate management.
- Continuous infusion techniques are emerging as a future strategy.
Conclusions:
- Continuous infusion of intravenous calcium antagonists is expected to provide safe and effective sustained control of ventricular response in atrial arrhythmias.
- This approach may overcome the limitations of current bolus-only methods.
- Future research should focus on optimizing and validating these infusion strategies.
Abstract:
Atrial fibrillation is one of the most common symptomatic sustained arrhythmias seen in clinical practice. Many patients with atrial fibrillation and a ventricular response greater than 120 beats/min will experience cardiac symptoms. In the past, control of heart rate in these patients consisted of administration of intravenous digoxin, but this often proved to be ineffective or limited by toxicity. Recently, intravenous beta blockers such as esmolol have been used to slow the ventricular rate during atrial arrhythmias, but in some studies their use has been limited by hypotension. Alternatively, a bolus of an intravenous calcium antagonist, e.g., diltiazem or verapamil, may be administered to achieve acute slowing of the ventricular response. An intravenous bolus of diltiazem or verapamil may be effective, but use of either may be limited by its short duration of action and the inability to administer repeated boluses to tightly control or "fine tune" the heart rate. However, a new bolus plus maintenance infusion technique with diltiazem has shown promise in initial studies. It appears that in the future, continuous infusion techniques with intravenous calcium antagonists will be available that provide safe and effective sustained control of the ventricular response during atrial arrhythmias.