This study aims to evaluate the role of preoperative vitamin D supplementation before coronary artery bypass grafting (CABG) surgery in preventing postoperative atrial fibrillation (POAF) in vitamin D deficient or insufficient patients. Three randomized controlled trials (RCTs) comprising 448 subjects were selected after a detailed search was conducted on PubMed, Cochrane CENTRAL, Scopus, and Embase in December 2022. Analysis was run using RevMan (version 5.4.1; Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014). The analysis collected risk ratio (RR) and 95% confidence interval (CI) data from the relevant studies, which were then pooled using a random effects model. A significance level of less than 0.05 (p<0.05) was considered significant. Our analysis showed that compared with the standard of care, preoperative vitamin D supplementation in vitamin D deficient and insufficient patients effectively reduced POAF after CABG surgery (RR=0.6, 95% CI=0.4-0.9, P=0.01). There was no significant difference in the duration of hospitalization between the vitamin D supplementation group compared with the control following CABG (mean difference -0.85, 95% CI -2.13 to 0.43, P = 0.19). This meta-analysis shows that preoperative vitamin D supplementation in vitamin D deficient and insufficient patients undergoing CABG can reduce the rate of POAF. As POAF is associated with many complications, providing vitamin D supplementation to individuals with a vitamin D deficiency undergoing CABG can improve long-term cardiovascular outcomes following surgery.

A 32-year-old female with no cardiac risk factors was admitted for treatment of a perianal abscess. During her hospital stay, she had a pulseless electrical activity arrest with a return of spontaneous circulation after one round of cardiopulmonary resuscitation (CPR). After transfer to the Intensive Care Unit (ICU), the patient had polymorphic ventricular tachycardia (PVT) requiring defibrillation shock. Her PVT was resistant to medical interventions. She was shocked a total of 33 times before her arrhythmia was terminated by passing a temporary transvenous pacemaker with overdrive pacing. After an extensive review of her history and presentation, no clear cause of her resistant arrhythmia was identified, however, she was found to have recently started taking over-the-counter weight loss supplements containing raspberry ketones which is a potentially cardiotoxic ingredient.