Background: The pathophysiology of isolated coronary artery ectasia (CAE) with the coronary slow flow (CSF) phenomenon is still unclear. The purpose of this study was to investigate the risk factors for isolated CAE complicated with CSF.
Methods: A total of 126 patients with isolated CAE were selected retrospectively. The patients were grouped into the no CSF (NCSF) group (n = 55) and the CSF group (n = 71) according to the corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC). Data on demographics, laboratory measurements, left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDd), CTFC and diameters of three coronary arteries were collected.
Results: The proportions of males (84.5% vs. 61.8%, p = 0.004) and patients with a smoking history (63.4% vs. 43.6%, p = 0.021) were higher in the CSF group than in the NCSF group. The neutrophil-to-lymphocyte ratio (NLR) (2.08(1.68-3.21) vs. 1.89 ± 0.58, p = 0.001), mean diameter of coronary arteries (mean D) (5.50 ± 0.85 vs. 5.18 ± 0.91, p < 0.001), and uric acid (URIC) level (370.78 ± 109.79 vs. 329.15 ± 79.71, p = 0.019) were significantly higher in the CSF group, while the lymphocyte-to-monocyte ratio (LMR) (4.81 ± 1.66 vs. 5.96 ± 1.75, p < 0.001) and albumin (ALB) level (44.13 ± 4.10 vs. 45.69 ± 4.11, p = 0.036) were lower. Multivariable logistic analysis showed that the LMR (odds ratio: 0.614, 95% CI: 0.464-0.814, p = 0.001), mean D (odds ratio: 2.643, 95% CI: 1.54-4.51, p < 0.001) and URIC level (odds ratio: 1.006, 95% CI: 1.001-1.012, p = 0.018) were independent predictors of CSF in CAE.
Conclusions: The LMR was a negative independent predictor of CSF in isolated CAE, while URIC level and mean D were positive independent predictors.
Keywords: Coronary slow flow; Isolated coronary artery ectasia; Lymphocyte-to-monocyte ratio; Mean diameter of arteries; Uric acid.