Cardioversion of chronic atrial fibrillation-towards a more aggressive approach

Poor maintenance of sinus rhythm after electrical cardioversion of patients with atrial fibrillation or flutter: a 5‐year follow‐up of 268 consecutive patients

OBJECTIVE

To report long-term results of direct current (DC)-cardioversion in unselected patients with atrial fibrillation (AF) or flutter.

DESIGN

The study was a retrospective 5-year follow-up of all patients undergoing DC-cardioversion for AF or flutter at our institution between 1993 and 1997.

RESULTS

Three hundred and eighty-five DC-cardioversions were performed in 268 patients. Two hundred and forty-nine patients underwent cardioversion for the first time. Of these, 183 (74%) were converted to sinus rhythm. During the first month of follow-up 105 (57%) relapsed into AF. Only 33 patients (13%) of the 249 patients scheduled for cardioversion remained in sinus rhythm after 1 year. In multivariate analysis arrhythmia duration was the only variable that was associated with successful cardioversion. Periprocedural complications occurred in 9.9% of the cardioversions.

CONCLUSION

In daily routine only a minority of patients will maintain sinus rhythm after DC-cardioversion for AF or flutter. Also, DC-cardioversion is not without risk. These observational data suggest a conservative approach to re-establishment of sinus rhythm in patients with AF.

Efficacy of amiodarone for the termination of chronic atrial fibrillation and maintenance of normal sinus rhythm: a prospective, multicenter, randomized, controlled, double blind trial

OBJECTIVE

We sought to assess the efficacy and safety of amiodarone for restoration and maintenance of sinus rhythm in patients with chronic atrial fibrillation in a prospective, randomized, double blind trial.

BACKGROUND

Restoration and preservation of sinus rhythm is difficult in patients with chronic atrial fibrillation. The efficacy of oral amiodarone has not been conclusively established.

METHODS

Ninety-five patients with chronic atrial fibrillation, lasting an average of 35.6 months, were randomized to either amiodarone (600 mg/d) (47 patients) or placebo (48 patients) during four weeks. Nonresponders underwent electric cardioversion, and those who reverted continued with amiodarone (200 mg/d) or placebo. End-points were successful cardioversion and sinus rhythm maintenance.

RESULTS

Sixteen patients (34.04%) in the amiodarone group reverted within 27.28 +/- 8.85 days in comparison with 0% in the placebo group (P < 0.000009). The conversion rate rose to 51.72% in patients with chronic atrial fibrillation lasting less than 12 months. Twenty-eight patients in the amiodarone group and 39 in the placebo group underwent electric cardioversion, which was successful in 19 patients (67.8%) of the amiodarone group and in 15 (38.46%) of the placebo group (P = 0.017). Altogether, conversion was obtained in 79.54% of the amiodarone group patients and in 38.46% of the placebo group patients (P < 0.0001). During follow-up, atrial fibrillation relapsed in 13 (37.14%) of 35 patients of the amiodarone group within 8.84 +/- 8.57 months and in 12 (80%; P = 0.009) of 15 patients of the placebo group within 2.74 +/- 3.41 months.

CONCLUSIONS

Oral amiodarone restored sinus rhythm in one third of patients with chronic atrial fibrillation, increased the success rate of electric cardioversion, decreased the number of relapses and delayed their occurrence.