- Atrial fibrillation is a cardiac rhythm disorder
that increases the risk of heart failure and stroke.
- Oral administration of vitamin C can prevent the
recurrence of post-operative atrial fibrillation, finds a review.
- Intravenous administration of vitamin C reduced the
length of hospital stay.
The risk of atrial fibrillation
can be reduced in high-risk patients after cardiac surgery with administration
of vitamin C, finds a systemic review by a research team at the University of Helsinki, Finland.
also known as an irregular heartbeat
can be triggered by stressful events. About 30% of the patients who undergo
cardiac operations suffer from post-operative atrial fibrillation. During atrial fibrillation the heart's two upper chambers (atria)
beat irregularly with the two lower chambers (ventricles). Atrial fibrillation can lead to blood clots, stroke, heart failure
‘Oral administration of vitamin C after cardiac surgery reduced the risk of atrial fibrillation by 73% in high-risk patients.’
Role of Vitamin C in Preventing Atrial
A research team from the University of Helsinki, Finland, conducted a systemic review
of vitamin C in preventing atrial fibrillation in cardiac patients. The team
identified 14 randomized cardiac surgery trials involving as many as 2006
patients who had undergone cardiac surgery. Another trial involving 44 patients
that had investigated the recurrence of atrial fibrillation after a successful
cardioversion was also reviewed.
According to the review,
- There was substantial heterogeneity between the 14
cardiac surgery trials because five trials were carried out in the USA and
nine trials were conducted outside of the USA.
- There was no effect
of vitamin C against post-operative atrial fibrillation in all
the five cardiac surgery trials conducted in the USA.
- However, the nine cardiac surgery trials conducted
outside the USA found a reduction in the incidence of post-operative
atrial fibrillation by 44%.
Five of the nine trials were
carried out in Iran, two in Greece, one in Slovenia and one in
Russia. A study conducted in Greece on the recurrence of atrial
fibrillation after a successful cardioversion found that vitamin C decreased
the risk of atrial fibrillation recurrence by 87%.
The studies conducted outside the
USA found that vitamin C decreased the length of hospital stay by 12.6% and intensive care unit stay by 8.0%.
Most of the cardiac surgery patients
in the non-US studies were administered vitamin C orally. Other patients were
administered vitamin C intravenously.
The effects of the two
administration methods might differ because the intravenous administration of vitamin C
the levels of vitamin C in the blood.
Post-Operative Atrial Fibrillation
The findings showed that oral administration of vitamin C decreased the occurrence of
post-operative atrial fibrillation by 73%,
but the intravenous administration decreased it by 36%.
Length of Hospital Stay
Intravenous administration of
vitamin C shortened the length of hospital stay by 16%. But, oral
administration shortened the length of hospital stay by only 7%. The effect of
intravenous administration of vitamin C was greater for the length of hospital
stay but less for the occurrence of post-operative atrial fibrillation.
from the University of Helsinki, Finland, and Timo Suonsyrjä from the Helsinki
University Central Hospital, Finland, said,
"Vitamin C is a safe low-cost essential nutrient. Given the consistent
evidence from the less wealthy countries, vitamin C might be administered to
cardiac surgery patients, although further studies are needed to find out
optimal protocols for its administration. However, there seems to be no
rationale for further study of unselected patients in wealthy countries, but
the effects of vitamin C for patients who have a particularly low documented
level of vitamin C might still be worthwhile."
- Harri Hemilä, Timo
Suonsyrjä. Vitamin C for preventing atrial fibrillation in high risk patients:
a systematic review and meta-analysis. BMC Cardiovascular Disorders, (2017); 17