Efficacy and safety of Qi-Jing Hui-Xin Decoction in the treatment of coronary microvascular angina: study protocol for a randomized, controlled, multi-center clinical trial

BACKGROUND: With the increased understanding of heart disease, microvascular angina (MVA) is receiving greater attention from clinicians. Studies have shown that patients with MVA have significantly higher major cardiovascular events and all-cause mortality than the control population, and the search for effective treatments is of great clinical importance. Both basic and clinical studies have shown that Qi-Jing Hui-Xin Decoction (QJHX) can relieve angina symptoms and improve clinical efficacy, but there is a lack of high-quality clinical studies to provide a research basis. This article introduces the evaluation protocol of QJHX for the adjunctive treatment of MVA. METHODS/DESIGN: This is a prospective randomized controlled trial. The trial will enroll 150 patients with MVA. On the basis of Western drug treatment, patients will be randomized into two groups, and the experimental group will receive QJHX treatment for 12 weeks and follow-up at 24 week. The primary indicators are the clinical efficacy of angina pectoris and the evidence of traditional Chinese medicine (TCM) efficacy. Secondary indicators are the Seattle Angina Scale score, serum lipid levels, electrocardiogram, and echocardiogram diagnosis. Additional indicators are endothelial function and immunoinflammatory factors. Adverse events will be monitored throughout the trial. DISCUSSION: Integrated traditional Chinese and Western medicine is commonly used for angina in China. This study will evaluate the clinical effectiveness and safety of adding QJHX based on standardized Western medications. The results of the trial will provide high-level clinical research-based evidence for the application of QJHX in MVA. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900027015. Registered on 28 October 2019. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13063-021-05508-x.