Preoperative serum potassium levels as a risk factor in postoperative atrial fibrillation in open cardiac surgery patient: A retrospective, observational study

Abstract

Background: Postoperative atrial fibrillation (POAF) is a postoperative complication that commonly occurs and is associated with increased mortality and morbidity. The electrolytes such as potassium are a modifiable risk factor for arrhythmia and POAF. This research assessed the correlation between preoperative serum potassium level and POAF after cardiac surgery. Patients and Methods: This study was a retrospective, observational study of patients who underwent heart surgery between October 2021 and March 2023. Preoperative serum potassium level was obtained the day prior to the surgery, and POAF was observed up to 24 h post-surgery. Other potential predictors, such as age, sex, cardiopulmonary bypass (CPB) time, body mass index, left ventricular (LV) ejection fraction, dysfunction, and dilatation (from preoperative echocardiography), and history of congestive heart disease (CHF), diabetes mellitus, and hypertension were also recorded. Result: Of the 86 samples, 23% of the subjects developed POAF. Bivariate analysis showed that preoperative serum potassium level was a significant predictor of POAF (relative risk 2.53, confidence interval [CI] 95% 1.160–5.524, P = 0.016). Furthermore, CPB time (adjusted odds ratio [OR] 9.37, CI 95% 1.05–83.09, P = 0.04) and a history of CHF (adjusted OR = 3.69, CI 95% 1.19–11.46, P = 0.02) also served as significant predictors of POAF. Conclusion: The preoperative serum potassium level was related to POAF incidence in cardiac surgery. A preoperative potassium level of <3.9 mmol/L was a significant predictor of POAF in open-heart surgery patients, as well as CPB time and the history of CHF.

Keywords

• atrial fibrillation
• cardiac surgery
• postatrial fibrillation
• potassium