EDN1 and angina pectoris: A systematic review and meta-analysis of randomized controlled trials (RCTs) involving 1,903 patients with CMVD revealed that integrated Chinese and Western medicine therapies were more effective than Western medicine treatments alone regarding the indicators of frequency of angina pectoris attacks, electrocardiography (ECG), nitroglycerin amounts needed, treadmill exercise tests, TCM syndrome scores, and levels of C-reactive protein (CRP), endothelin-1 (ET-1), and nitric oxide (NO) (Zhong et al., 2020).