Relationship between Prediction of Platelet-Lymphocyte Ratio and Atrial Fibrillation in Perioperative Patients: A Systematic Review and Meta-Analysis

Background: The platelet-to-lymphocyte ratio (PLR) could be a convenient method to predict atrial fibrillation (AF) likelihood and, in turn, to determine the patients' postoperative trajectory. This study aimed to evaluate the prognostic effect of pre-intervention PLR in predicting the occurrence of AF after surgery. Methods: PubMed, Embase, and the Cochrane library were searched for available papers published up to October 2023. The primary outcome was the odds ratio (OR) of numerical PLR in the model predicting AF occurrence. The random-effects model was used in all analyses. Results: Six studies were included. There were 1197 patients with AF and 1998 patients without AF. The combined analysis of all six studies showed that PLR was associated with AF after surgery (OR = 1.01, 95% confidence interval (CI): 1.00–1.01, p = 0.000; I2 = 43.4%, pheterogeneity = 0.116). Three studies examined PLR before coronary artery bypass graft (CABG), and the meta-analysis showed that PLR was associated with AF after CABG (OR = 1.01, 95% CI: 1.00–1.02, p = 0.002; I2 = 0.0%, pheterogeneity = 0.894). The sensitivity analysis showed that the results were not robust. There was no obvious publication bias. Conclusions: Pre-intervention PLR was significantly associated with post-intervention AF in patients who underwent CABG or other surgeries. Elevated PLR is a risk factor for postoperative atrial fibrillation.