Factors Predicting Maintenance of Sinus Rhythm after Direct Current Cardioversion of Atrial Fibrillation and Flutter: A Reanalysis with Recently Acquired Data

Abstract

A prospective study was conducted to evaluate how many patients maintain normal sinus rhythm after direct current (DC) cardioversion of atrial arrhythmias and to assess factors predictive of long-term success. The study group consisted of 61 patients (45 men) aged 18-88 years (mean age 66 ± 11 years) who underwent cardioversion at our department from October 1990 to June 1992. Prior to cardioversion, the patients’ medical history, medications, heart size on chest X ray, and echocardiographic findings were reviewed. Overall, 41 (67.2%) patients were in atrial fibrillation, while 20 (32.8%) had atrial flutter. Only 15% of the patients had valvular heart disease. Sinus rhythm was restored by DC cardioversion in 47 (77%) patients, none of whom experienced an embolic event prior to discharge. Patients with atrial flutter had a higher conversion rate (95%) than those in atrial fibrillation (68.3%; p = 0.024), and also patients with an arrhythmia for less than 1 week (94.4%) compared to those with a longer or unknown duration (69.8%; p = 0.047). The primary success rate was not influenced by heart size on chest X ray or echocardiographic variables. The study protocol aimed at following up the patients for 1 year after cardioversion. Of the 47 patients who converted to sinus rhythm data are available on 44 for a mean follow-up of 11 ± 3 months (range 1-14 months), at which time 25 (57%) still remained in sinus rhythm. Heart size on the chest X ray was significantly increased in the group that did not maintain sinus rhythm (p = 0.03) and their left atrial size on echocardiography was slightly increased (p = 0.10). Patients who originally had atrial flutter were more likely to remain in sinus rhythm than those who had been in atrial fibrillation (p = 0.12), as did patients with an arrhythmia for less than 1 week prior to cardioversion in comparison to those with a longer or unknown duration (p = 0.11). Thus, in contrast to previous reports, according to these recent data on a patient population with a low prevalence of valvular heart disease, DC cardioversion can be attempted in most patients with atrial tachyarrhythmias. Clinical factors, heart size on chest X ray and echocardiographic findings should, however, be considered before deciding to perform DC cardioversion.

The Predictive Value of Transthoracic Echocardiographic Variables for Sinus Rhythm Maintenance after Electrical Cardioversion of Atrial Fibrillation

“…Over the past years, great effort has been undertaken to restore sinus rhythm with electrical cardioversion. However, this strategy has shown limited success over time with a high recurrence rate after 1 year: typically 70–80% in patients not treated with antiarrhythmic drugs [2]. In the literature, recurrence of atrial fibrillation after cardioversion has been found to be associated with transthoracic echocardiographic parameters like left atrial diameter, left ventricular function and mitral inflow A wave velocity.…”

“…In the literature, recurrence of atrial fibrillation after cardioversion has been found to be associated with transthoracic echocardiographic parameters like left atrial diameter, left ventricular function and mitral inflow A wave velocity. Most of these studies are retrospective or include a limited number of patients, and the results are to some degree conflicting [2,3,4,5,6,7]. …”

Prognostic Implication of the Left Atrial Appendage Mechanical Reserve After Cardioversion of Atrial Fibrillation

“…Although the immediate success rate of CV has been reported to be up to 70-95%, the rate of long term SR maintenance is only approximately 50-60%. [10][11][12][13][14] In addition to AF duration and the left atrial dimension, the left atrial appendage (LAA) mechanical function has been suggested as an important factor for successful CV of AF and the maintenance of SR. [15][16][17][18][19][20] After electrical CV, atrial mechanical stunning develops, which presents as diminished LAA flow velocities. 18,21 This atrial stunning can be reversed by isoproterenol infusion.…”

Atrial Therapies Reduce Atrial Arrhythmia Burden in Defibrillator Patients

“…3 In addition, patients with an indication for a ventricular defibrillator must be exposed to the risk of device implantation, so that a device capable of treating both atrial and ventricular arrhythmias may add therapeutic benefit with little or no additional risk. Although maintenance of sinus rhythm is more difficult in the setting of cardiac structural abnormalities, 15 we found that atrial tachyarrhythmia burden was significantly reduced in this population. Reduction in AT/AF burden may improve quality of life, reduce tachycardia-induced cardiomyopathy, and/or reduce the number of hospitalizations.…”