Persistent atrial fibrillation: a population based study of patients with their first cardioversion.

BACKGROUND

Electrical cardioversion is effective in terminating even long standing atrial fibrillation (AF), but the relapse risk of AF is high. Data on long-term success of cardioversion in real life clinical practice are scant.

METHODS

Restoration and maintenance of sinus rhythm as well as acceptance of permanent AF was studied in a population based cohort (catchment area with a population of 440,000) of patients with persistent AF after first elective cardioversion.

RESULTS

Of the 183 patients having their first electrical cardioversion during the 1-year study period, sinus rhythm was restored in 153 patients (84%). Only 39 of these (25%) maintained sinus rhythm for 1 year, even though 108 (71%) patients had anti-arrhythmic medication. Age, hypertension, coronary artery disease, heart failure and valvular disease, or absence of these known risk factors for AF were not associated with the outcome. The outcome was better if the cardioversion was performed earlier than the median delay (78 days) from the diagnosis of AF to cardioversion compared to longer delay (P=0.022 in multivariate modelling). The decision of acceptance of permanent AF was made in 74 cases (40%) during 1 year of follow-up.

CONCLUSIONS

Patients with persistent AF had a high tendency to remain in or relapse into AF, even though most patients had anti-arrhythmic medication after first cardioversion. Short history of arrhythmia was associated with better outcome. Acceptance of permanent AF was made in almost half of the cases during 1 year of follow-up.