Related Experiment Videos
Absence of cardioversion-induced ventricular arrhythmias in patients with therapeutic digoxin levels
Insights
Patients with therapeutic serum digoxin levels can safely undergo cardioversion for atrial fibrillation. This study found no increased risk of ventricular arrhythmias, even without antiarrhythmic drugs.
Area of Science:
- Cardiology
- Clinical Electrophysiology
Background:
- Digoxin is commonly used for rate control in atrial fibrillation.
- Cardioversion is a standard treatment for atrial fibrillation.
- Concerns exist regarding digoxin's proarrhythmic potential during cardioversion.
Purpose of the Study:
- To assess the incidence of ventricular arrhythmias after cardioversion in patients with therapeutic digoxin levels.
- To evaluate the safety of cardioversion in patients on digoxin therapy.
- To determine if digoxin levels or shock energy influence arrhythmia development.
Main Methods:
- Prospective study of 19 patients undergoing elective cardioversion for atrial fibrillation.
- Inclusion criteria: therapeutic serum digoxin levels (0.5-1.9 ng/ml), absence of contraindications.
- 24-hour ambulatory ECG monitoring before and 6 hours after cardioversion.
Main Results:
- No malignant ventricular arrhythmias (ventricular tachycardia/fibrillation) occurred post-cardioversion.
- No significant difference in ventricular premature beats or couplets before and after cardioversion.
- No significant correlation found between serum digoxin levels, shock energy, and arrhythmia frequency.
Conclusions:
- Cardioversion appears safe in patients with therapeutic serum digoxin levels.
- Concomitant use of Class I antiarrhythmic agents may not be necessary.
- Further research could explore broader patient populations and varying digoxin concentrations.
Abstract:
To determine the incidence of cardioversion-induced ventricular arrhythmias in patients with therapeutic serum levels of digoxin, 19 patients (average age [+/- standard deviation] 61 +/- 12 years) undergoing elective direct current cardioversion for atrial fibrillation were studied. Only patients with therapeutic serum digoxin levels (range 0.5 to 1.9 ng/ml; mean 1.1 +/- 0.5) at the time of cardioversion were included. Patients with acute myocardial ischemia or unstable angina, serious electrolyte disturbance or those requiring class I antiarrhythmic agents for control of ventricular or supraventricular arrhythmias were excluded. Ambulatory electrocardiograms were recorded for 24 hours before and 6 hours after cardioversion. No patient developed malignant ventricular arrhythmias (ventricular triplets or tachycardia) in the immediate 3 hour period after cardioversion. Furthermore, there were no significant (p less than 0.05) differences in the frequency of ventricular premature beats or couplets before and after cardioversion. To determine whether the level of serum digoxin or the strength of the applied shock had a significant effect on the development of postcardioversion arrhythmias, the change in frequency of single premature ventricular beats after cardioversion was compared with the serum digoxin level (ng/ml) and the applied energy level (joules) by means of linear regression analysis. There was no significant (p less than 0.05) relation between these variables. These findings suggest that patients with therapeutic serum levels of digoxin may safely undergo cardioversion without the concomitant use of class I antiarrhythmic agents.