Comparison of recurrence rates after direct-current cardioversion for new-onset atrial fibrillation in patients receiving versus those not receiving rhythm-control drug therapy

The AFFIRM investigators have recommended rate control as the preferred strategy for recurrent atrial fibrillation (AF), but the appropriate strategy for new onset persistent AF is uncertain. Our study evaluated the AF recurrence rate and the impact of rhythm-control drugs (class 1 A, 1 C, and 3 antiarrhythmic drugs) on patients with new-onset persistent AF after successful direct-current. (DC) cardioversion. Consecutive patients who underwent DC cardioversion of AF from January 1, 1996 to December 31, 1999 were screened for new-onset persistent AF, and 150 patients met the inclusion criteria. After the first DC cardioversion, 50 patients received rhythm-control drugs (rhythm-control group) and the, other 100 did not (rate-control group). The 2 groups had similar clinical characteristics except for a lower ejection fraction (44 +/- 14% vs 49 +/- 14%, p < 0.01) and a higher proportion of idiopathic dilated cardiomyopathy (20% vs 10%, p = 0.03) in the rhythm-control group versus the rate-control group. During the follow-up period there was a trend toward a lower rate of early AF recurrence at 24 hours after DC cardioversion in the rhythm-control group versus the rate-control group (6% vs 16%, p = 0.11), but there was a high recurrence rate of AF in both groups at 1 month (30% for the rhythm-control group vs 41 % for the rate-control group, p = 0.25). At the end of the follow-up period, rhythm-control therapy was abandoned in 78% of the rhythm-control group patients after the failure of 1 to 3 rhythm-control drugs. In the rate- control I group, rhythm-control therapy was attempted after AF recurrence in 62 patients but was later abandoned in 48 patients (77%) because of treatment failure. Therefore, the high incidence of treatment failure with rhythm-control therapy suggests that. rate control with anticoagulation should be preferred in patients with new-onset persistent AF if All recurs after DC cardioversion. (C) 2003 by Excerpta Medica, Inc.