Background: The activation of the renin-angiotensin-aldosterone system has been implicated in the progression of atrial structural remodeling during atrial fibrillation (AF). However, consequences of the changes of aldosterone in AF have not been evaluated.
Objectives: This study's aim was to evaluate changes of serum aldosterone concentration after successful cardioversion of persistent AF and to determine the prognostic value of these changes.
Methods: The prospective, single center study included 45 consecutive patients with nonvalvular persistent AF and preserved left ventricular systolic function, referred for cardioversion. None of the patients were taking aldosterone antagonists. Blood samples for aldosterone measurement were collected twice: 24 hours before and 24 hours after cardioversion.
Results: Forty-three patients were successfully converted to sinus rhythm. On the 30th day following cardioversion, 24 patients maintained sinus rhythm (group A), 19 patients relapsed to AF (group B). Serum aldosterone concentration before cardioversion did not differ significantly between both groups (175.6 +/- 112.82 pg/mL vs 125.8 +/- 51.2 pg/mL; P = 0.25). However, in group A serum aldosterone level decreased significantly within 24 hours after cardioversion, from 175.6 +/- 112.8 pg/mL to 101.4 +/- 44.2 pg/mL (P = 0.0034). In group B, the aldosterone level before and after cardioversion did not differ significantly (125.8 +/- 51.2 pg/mL vs 118.2 +/- 59.6 pg/mL; P = 0.68). Logistic regression analysis revealed that a decrease in plasma aldosterone concentration after direct current cardioversion more than 13.2 pg/mL predicted sinus rhythm maintenance in a 30-day follow-up, with 87% sensitivity and 64% specificity.
Conclusions: There is a positive correlation between the fall in aldosterone concentration 24 hours after cardioversion and maintenance of sinus rhythm during 30 days of observation.