Preoperative Platelet-to-Lymphocyte Ratio Is Not Associated With Postoperative Atrial Fibrillation.

Background: Postoperative atrial fibrillation (POAF) is a common complication after coronary artery bypass grafting (CABG) and is associated with increased short-term and long-term mortality. While the precise etiology of POAF remains unclear, inflammation is a known contributing factor. Preliminary studies have suggested that an elevated preoperative platelet-to-lymphocyte ratio (PLR), an inexpensive and readily available novel inflammatory biomarker, may be associated with increased incidence of POAF after CABG. This study sought to further investigate this hypothesis.

Methods: The study cohort included all patients undergoing isolated CABG, with no prior history of arrhythmia, who were operated on between August 1, 2010, and December 31, 2018, at a major Australian tertiary center (n = 1457). Patients were divided into low (<86) or high (≥86) PLR groups based on an optimal cutoff derived from receiver-operating characteristic curve analysis. The incidence of POAF was then compared. Categorical variables were analyzed using the chi-square test and continuous variables using logistic regression.

Results: Of 1457 patients, 495 (34.0%) developed POAF. There was no statistically significant difference in the incidence of POAF between patients in the high-PLR and low-PLR groups (34.8% vs 31.0%; P = .22). Using multivariable logistic regression analysis, high PLR was not independently associated with POAF (odds ratio, 1.04; P = .78).

Conclusions: Elevated preoperative PLR is not independently associated with POAF in patients undergoing isolated CABG. The findings of this study differ from those of 2 previous smaller studies.