Oral vitamin C appears to cut the risk of early recurrence of abnormal health rhythm, as know as atrial fibrillation, after patients undergo electrical cardioversion, according to a new study. Vitamin C also appears to reduce the low-level inflammation that accompanies this condition.

Early atrial fibrillation recurrence after cardioversion may be due to electrophysiological changes in the chambers of the heart, known as atrial remodeling, Dr. Panagiotis Korantzopoulos of ‘G. Hatzikosta’ General Hospital in Ioannina, Greece, and colleagues report in the International Journal of Cardiology.

Animal studies have shown vitamin C can help prevent such remodeling, they note, and the vitamin has been shown to reduce atrial fibrillation after cardiac surgery.

To investigate whether vitamin C can reduce atrial fibrillation recurrence, the team randomized 44 consecutive patients who had undergone cardioversion for persistent atrial fibrillation to standard therapy plus oral vitamin C or standard treatment only. Patients given the vitamin received a 2-gram loading dose 12 hours before cardioversion and 500 mg twice daily for the next seven days.

One (4.5 percent) of the patients given vitamin C had a relapse of atrial fibrillation, while eight (36.3 percent) of patients not given the vitamin did.

The researchers also found that white blood cell levels and fibrinogen levels fell significantly in the group given vitamin C, but did not drop in the control patients. Markers of inflammation were also significantly higher among patients who had a recurrence of atrial fibrillation, compared with those who did not.

Korantzopoulos and colleagues point out that extensive damage has been identified in the hearts of atrial fibrillation patients, and there is also increasing evidence for a link between atrial fibrillation and inflammation.

While the study is small, they say, their findings show approaches targeting the oxidative damage and inflammation involved in atrial fibrillation are worth pursuing.

SOURCE: International Journal of Cardiology, July 2005.