Cardiac syndrome X (CSX) is also known as microvascular angina pectoral, the pathogenesis of which has not been clearly determined . A coronary angiography study  showed that neutrophil to lymphocyte ratio (NLR), as a marker of inflammatory response in a variety of cardiovascular diseases, was elevated in CSX patients. The NLR of CSX patients with impaired myocardial perfusion was higher than that of patients without it, such as unstable angina pectoris (UAP) patients. In this study, we found that the distribution of myocardial first-pass perfusion was heterogeneous in each segment of CSX patients in the resting stage, better than that of UAP patients. The correlation between perfusion parameters and NLR was high and significant.