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Abstract

Background: Coronary artery spasm (coronary artery spasm CAS) is a common clinical symptoms of a group to rest as the main performance of chest pain, ECG can be accompanied by transient ST-elevation. CAS is not only the variability of the main pathogenesis of angina pectoris and ischemic heart disease for many, including unstable angina, acute myocardial infarction and sudden cardiac death of one of the foundations of an important pathophysiological mechanism is not yet clear, studies have shown may be related to vascular endothelial function disorders, vascular smooth muscle, and abnormal systolic and diastolic function of the imbalance of the autonomic function. CAS is currently rely mainly on the diagnosis of coronary provocation test, including acetylcholine and ergonovine test pilot, domestic scholars have found in 201Tl (Tl) SPECT myocardial perfusion imaging in the cardiac stress test was reverse redistribution (reverse redistribution RR) is CAS One of the characteristics of patients, if the combination of exercise electrocardiography test negative as well as the rest of the clinical features of chest pain, diagnosis of coronary artery spasm highest sensitivity and can be made respectively 98% and 90% respectively. But the reverse redistribution of the clinical significance is still controversial, this article aims to compare patients with myocardial perfusion imaging stress test before and after the plasma ET-1, NO content, as well as changes in the level of ET-1/NO to further explore the re-distribution of the reverse the relationship between vascular endothelial function.
Objective: To evaluate the coronary artery spasm (CAS) in patients with 201Tl (Tl) SPECT myocardial perfusion imaging in the cardiac stress test was reverse redistribution (RR) phenomenon and the relationship between vascular endothelial function.