- 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.
Atrial FibrillationAtrial fibrillation 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.
Role of Vitamin C in Preventing Atrial FibrillationA 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.
- 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%.
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 increases the levels of vitamin C in the blood.
Post-Operative Atrial FibrillationThe 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 StayIntravenous 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.
Harri Hemilä 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 (1) DOI: 10.1186/s12872-017-0478-5