Influence of Vitamin C on Post-operative Atrial Fibrillation

Study Overview
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Brief Summary
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Post-operative atrial fibrillation (POAF) is the most common arrhythmia which typically develops 2-3 days after cardiac surgery. The incidence of POAF variates between 10% and 65% depending on the type of cardiac surgery and is especially high in patients which underwent Coronary Artery Bypass Grafting (CABG) and heart valve surgery. POAF is associated with increased morbidity and mortality and has a major impact on hospital resources. The precise pathogenesis of POAF is very complex, but several studies have demonstrated an association between inflammation, oxidative stress and POAF. Since this oxidative stress may be reduced by dietary anti-oxidantia such as vitamin C, the aim of this study is to evaluate the effect of oral vitamin C administration of the incidence of POAF.

Detailed Description
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After obtaining informed consent, patients which are planned for CABG or heart valve surgery are randomly assigned into the Vitamin C group or Placebo Group. Each patient will receive 1 g Vitamin C or Placebo twice a day from 5 days before until 10 days after surgery. The medication will be given orally and both patient and surgeon are blinded for the administrated medication. Patients receive standard of care in the post-operative period, which includes close monitoring for possible arrhythmias. If such an arrhythmia develops, this is treated according to the normal procedures. All information such as the used medication, the hospitalization / ICU length of stay and the ventilation time is automatically registered in the patient records. From each patient, three additional blood samples (peri-operative, post-operative Day 0, post-operative Day 1) will be obtained for analysis of Neutrophil gelatinase-associated lipocalin (NGAL), a possible marker of subclinical kidney damage. These samples will be analysed in batch once all samples are collected.

Official Title
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Influence of Oral Vitamine C Supplementation on the Incidence of Post-operative Atrial Fibrillation

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Dietary Supplement: Vitamin C
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: signed informed consent eligible for elective cardiac surgery preoperative sinus rhythm Exclusion Criteria: patients who do not want to participate

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: One group receives Vitamin C, the other group received placebo.
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Vitamin C<br>Vitamin C 1000mg PO from 5 days before surgery until 10 days after surgery | Dietary Supplement: Vitamin C<br>* 1 gram Vitamin C will be administrated orally, twice a day from 5 days before until 10 days after surgery.<br>|
| Placebo Comparator: Placebo<br>Placebo as an alternative for Vitamin C tablets | Other: Placebo<br>* 1 gram Placebo will be administrated orally, twice a day, from 5 days before until 10 days after surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arrhythmia | Incidence | First 5 days postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| hours of endotracheal ventilation | number of hours of endotracheal ventilation after surgery | from arrival at ICU after surgery until the time of discharge from ICU. average 48 hours. | 
| Length of stay at ICU | number of hours in the Intensive Care Unit | from time of arrival at ICU after surgery until the time of discharge from ICU. upto 14 days. average 48 hours. | 
| Length of stay in the hospital | number of hours in the hospital | from time of arrival at ICU after surgery until the time of hospital discharge. upto 120 days. | 
| Cost of postoperative medication | Total cost (€) of postoperative medication | from time of arrival at ICU after surgery until the time of hospital discharge. upto 120 days | 
| subclinical kidney damage | change in Value of NGAL between pre-incision and post-CPB | after induction of anesthesia and two hours after CPB | 
| Postoperative complications | Number of unexpected complications requiring medical interventions | from time of arrival at ICU until the time of hospital discharge. upto 120 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Post-operative atrial fibrillation, Ascorbic Acid, Vitamin C, antioxidant, Cardiac surgery