Oral vitamin C administration reduces early recurrence rates after electrical cardioversion of persistent atrial fibrillation and attenuates associated inflammation

Abstract

Background: Inflammation and oxidative stress have been recently implicated in the pathophysiology of atrial fibrillation (AF). The aim of this study was to examine the potential benefit of vitamin C on the early recurrence rates and on inflammatory indices after successful cardioversion of persistent AF, as well as to investigate the time course of changes in these indices post-cardioversion.

Methods: We prospectively studied 44 consecutive patients after successful electrical cardioversion of persistent AF. All patients received standard treatment and were randomised in one to one fashion to either oral vitamin C administration or no additional therapy. We followed-up the patients for 7 days performing successive measurements of white blood cell (WBC) count, C-reactive protein (CRP), fibrinogen, and ferritin levels.

Results: One week after successful cardioversion, AF recurred in 4.5% of patients in the vitamin C group and in 36.3% of patients in the control group (p=0.024). Compared to baseline values, inflammatory indices decreased after cardioversion in patients receiving vitamin C but did not change significantly in the control group. A significant variance was found in the serial measurements of WBC counts (F=5.86, p=0.001) and of fibrinogen levels (F=4.10, p=0.0084) in the two groups. In the vitamin C group CRP levels were lower on the seventh day (p<0.05). CRP and fibrinogen levels were higher in patients who relapsed into AF compared to patients who maintained sinus rhythm (F=2.77, p=0.044 and F=3.51, p=0.017, respectively).

Conclusions: These findings suggest that vitamin C reduces the early recurrence rates after cardioversion of persistent AF and attenuates the associated low-level inflammation. These effects indicate that therapeutic approaches targeting at inflammation and oxidative stress may exert favourable effects on atrial electrical remodeling.