Neutrophil/Lymphocyte Ratio in Patients Undergoing Noncardiac Surgery After Coronary Stent Implantation

Abstract

Objective: Perioperative cell count-associated predictors, including the neutrophil/lymphocyte ratio (N/LR) and platelet/lymphocyte ratio (P/LR), are associated with poor clinical outcomes including myocardial injury. Study investigators aimed to examine the association among the perioperative N/LR, P/LR, and postoperative major adverse cardiovascular and cerebral events (MACCE) after noncardiac surgery in patients with drug-eluting stent (DES) insertion.

Design: Retrospective and observational.

Setting: Single university hospital.

Participants: The study comprised 965 patients who underwent noncardiac surgery within 6 months after DES implantation.

Interventions: None.

Measurements and main results: Baseline perioperative clinical parameters, including N/LR and P/LR measured before surgery, immediately after surgery, and on postoperative day (POD) 1, were obtained. MACCE was defined as a composite of nonfatal myocardial infarction, coronary revascularization, nonhemorrhagic stroke, and pulmonary embolism within 1 month after surgery. Multivariate logistic regression analysis and propensity score matching were used to identify predictors of MACCE after surgery. MACCE occurred in 67 patients (6.9%) and was more common in patients with N/LR on POD 1 >4.3 (multivariable-adjusted odds ratio [OR] 2.03, 95% confidence interval [CI] 1.12-2.79; p = 0.040 and as a continuous N/LR [OR 1.17, 95% CI 1.08-1.27; p < 0.001]). This association was consistent after propensity score matching and was stronger when the antiplatelet agent was stopped before surgery (OR 3.02, 95% CI 2.14-4.48; p = 0.006 for stopping dual antiplatelet therapy).

Conclusions: In patients undergoing noncardiac surgery within 6 months after DES implantation, elevated N/LR on POD 1 is independently associated with postoperative MACCE. Elevated postoperative N/LR as a marker of systemic inflammation may help to predict the development of MACCE in these high-risk patients.

Keywords: coronary stent; lymphocyte; major adverse cardiovascular event; neutrophil; platelet; surgery.