Association of eosinophil-to-lymphocyte ratio with coronary slow-flow phenomenon in patients undergoing coronary angiography

Introduction
The current investigation intended to evaluate the correlation between eosinophil-to-lymphocyte ratio (ELR) and the coronary slow-flow phenomenon (CSFP) in patients undergoing elective coronary angiography.

Material and methods
A case-control investigation was conducted on 200 individual CSFP patients and another 200 individuals with normal coronary arteries and who were matched for age, gender, and body mass index. ELR was computed by dividing the number of eosinophils by the number of lymphocytes. Thrombolysis in myocardial infarction frame count was used to determine the CSFP.

Results
The ELR in the CSFP group was substantially greater than in the control group [0.38 (0.28–0.50)] and [0.22 (0.17–0.35)], p < 0.001, respectively). With the help of multivariable logistic regression analysis, ELR independently predicted the CSFP presence (odds ratio = 1.040, 95% CI: 1.026–1.053), p < 0.001). The effective cutoff point of ELR in predicting CSFP presence was > 0.29 with sensitivity of 77% and specificity of 70%. ELR had better diagnostic accuracy to predict CSFP than either lymphocyte or eosinophil count alone [AUC = 0.746 vs. AUC = 0.687 vs. AUC = 0.687, respectively].

Conclusions
To our knowledge, this was the first investigation to determine the connection between ELR and CSFP. We discovered that individuals with CSFP had higher ELR than those with normal coronary arteries in the control group.