The effectiveness and safety of nicorandil in the treatment of patients with microvascular angina A protocol for systematic review and meta-analysis

Background: Microvascular angina has become a clinical and frequent cardiovascular disease in recent years, which is complicated and there is no clear treatment. Today, Western medicine still deals with microvascular angina with standardized treatment based on the stable angina. Firstly, it is to control the risk factors of atherosclerosis, and the second is to reduce the oxygen consumption of the patient's heart muscle. In the previous randomized controlled clinical trials, it has shown that nicorandil can improve the symptoms of angina for the treatment of microvascular angina, but there is a lack of high-quality randomized controlled trials on the clinical effectiveness and safety of nicorandil in the treatment of microvascular angina, and the lack of evaluation of its effectiveness and safety. Therefore, this paper aims to understand whether nicorandil can further improve the prognosis of patients with microvascular angina and the safety of the drug through the method of systematic evaluation. Methods: Retrieval of relevant network electronic databases by computer: SinoMed, CNKI, WanFang Data, VIP, PubMed, EMbase and The Cochrane Library, the retrieval time is from the establishment of each database to December 2017, to collect randomized controlled studies of nicorandil in the treatment of microvascular angina. At the same time, it is supplemented by manual search of the included literature references, as far as possible to increase the included literature imformation. Two researchers independently browse the topics and abstracts, and select, find, read the full text of the relevant literature, and screen the literature according to the criteria for inclusion and exclusion established in advance, then extract the data, and cross-check, and resolve the differences through multi-person discussion. Data analysis of collected information is performed by using RevMan 5.3 software. Results: The data of the included literature are statistically analyzed by meta-analysis, and the key outcome indicators are used to determine whether nicorandil can further improve the prognosis of patients with microvascular angina and the safety of the drug. Conclusion: Through the method of evidence-based medicine, this study finds the existing problems and defects in the current research, which will provide high-quality evidence-based medical evidence for nicorandil's treatment of microvascular angina, and it help the clinical treatment and further research. OSF registration number: DOI 10.17605/OSF.IO/DSQG9.