BACKGROUND Coronary slow flow phenomenon (CSFP) is an angiographic entity characterized by delayed coronary opacification in absence of evident obstructive lesion in the epicardial coronary artery. However, whether patients with CSFP exhibit differing responses to exercise is still not known. This study aimed to evaluate results of exercise stress electrocardiography (ExECG) and left ventricular (LV) function during exercise, and study the value of ExECG for stratification of exercise capacity and LV function in patients with CSFP. METHODS Thirty patients with CSFP and 24 controls were enrolled in the study. Diagnosis of CSFP was made by Thrombolysis in Myocardial Infarction frame count. ExECG and LV function measured by echocardiography at rest, during exercise and recovery phase were evaluated. RESULTS Negative ExECG was found in 24 (80%) patients with CSFP. At rest, LV global longitudinal strain (GLS) decreased and mitral average E/e' increased in patients with CSFP compared with controls; however, there were no differences in these parameters between CSFP patients with negative ExECG and patients with positive ExECG. During exercise, CSFP patients with negative ExECG and controls had significantly increased LV GLS and decreased mitral average E/e', but CSFP patients with positive ExECG had significantly decreased LV GLS and increased mitral average E/e'. CONCLUSIONS About 80% patients with CSFP exhibited negative ExECG. CSFP patients with negative ExECG exhibited improved LV function but CSFP patients with positive ExECG exhibited impaired LV function during exercise. ExECG may aid in the stratification of exercise capacity and LV function in patients with CSFP.

中文翻译：

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运动负荷心电图对运动能力和左心室收缩和舒张功能分层对冠状动脉慢血流的价值：病例对照研究。

背景技术冠状动脉缓慢流动现象（CSFP）是一种血管造影实体，其特征在于在心外膜冠状动脉中没有明显的阻塞性病变的情况下延迟了冠状动脉混浊。但是，尚不清楚CSFP患者对运动表现出不同的反应。本研究旨在评估运动应激性心电图（ExECG）和运动过程中左心室（LV）功能的结果，并研究ExECG对CSFP患者运动能力和LV功能进行分层的价值。方法本研究共纳入30例CSFP患者和24例对照。通过溶栓治疗心肌梗死帧数对CSFP进行诊断。评估了在休息，运动和恢复阶段通过超声心动图测量的ExECG和LV功能。结果在24名（80％）CSFP患者中发现ExECG阴性。静息时，与对照组相比，CSFP患者的左室总纵应变（GLS）降低，二尖瓣平均E / e'升高；但是，ExECG阴性的CSFP患者和ExECG阳性的患者在这些参数上没有差异。在运动过程中，ExECG阴性且对照组的CSFP患者的LV GLS显着升高，二尖瓣平均E / e'降低，而ExECG阳性的CSFP患者的LV GLS的显着降低，二尖瓣平均E / e'升高。结论约80％的CSFP患者ExECG阴性。ExECG阴性的CSFP患者表现出改善的左室功能，但ExECG阳性的CSFP患者在运动过程中表现出左室功能受损。