Vitamin D Levels in Post-Operative Atrial Fibrillation (POAF) after Coronary Artery Bypass Graft Surgery: A Case Control Study

Abstract

Objective: To determine if pre-operative vitamin D deficiency is associated with onset of postoperative atrial fibrillation (POAF) following coronary artery bypass graft (CABG) operation. Study Design & Setting: A Case control study conducted in the Department of Cardiac Surgery, Cardiac Unit PNS Shifa Hospital Karachi, Pakistan from November 2021 to February 2023. Methodology: Vitamin D levels were estimated pre-operatively upon admission in 48 patients scheduled for isolated, elective CABG surgery. The data obtained from study population comprising both cases (POAF) and controls (NON POAF) was evaluated statistically to know whether vitamin D levels and the development of post-operative atrial fibrillation are correlated. Results: Those patients with coronary artery disease who were operated for CABG surgery was followed in this study for the effects that vitamin D may have on the POAF onset. The study population included 12(25%) patients with POAF identified in first five days post-operatively were assigned to POAF (YES) group and the remaining 36(75%) in sinus rhythm were in POAF (NO) group. After matching the base line characteristics, the patients in POAF (YES) group revealed significantly lesser vitamin D levels compared to those in the POAF(NO) group (27.62±23.11 & 77.42±29.08 nmol/L, P=0.0001 respectively). In the POAF (YES) group Left atrial dimension and LV diastolic dimension were also higher than in POAF (NO) group. Conclusion: POAF after CABG surgery was more frequent in patient with deficient or insufficient preoperative vitamin D levels compared to normal levels. Therefore, it may be associated with POAF development in those patients proceeding for CABG operations.