Efficacy and safety of integrated traditional Chinese medicine and standard Western medicine for patients with acute coronary syndrome: protocol for a systematic review and meta-analysis

Introduction

Acute coronary syndrome (ACS), which usually results from the buildup of fatty deposits (plaques) in and on the walls of coronary arteries, remains a major cause of morbidity and mortality worldwide and is responsible for more than 1 million hospital admissions in America (1). ACS comprises two presentations in clinic: ST elevation myocardial infarction (STEMI) and non–ST elevation acute coronary syndrome (NSTE-ACS), with the latter being further divisible into unstable angina pectoris (UAP) and acute non-STEMI (NSTEMI) (2). ACS has many predisposing factors, including hypertension, smoking, obesity diabetes, etc. The main clinical symptoms mainly include chest tightness and chest pain, and in some serious cases ACS can even lead to heart failure and death (3). Given the above facts, we consider that optimizing the current treatment for ACS will have important clinical implications.

Percutaneous coronary intervention (PCI), which is a non-surgical procedure that uses a catheter (a thin flexible tube) to place a small structure called a stent to open up blood vessels in the heart, has an immediate effect on revascularization of an infarct related artery (4). It has been widely applied and has significantly improved the prognosis of ACS (5). However, some PCI-related problems, including perioperative myocardial injury, in-stent restenosis, stent thrombosis, no-reflow, and ischemia-reperfusion injury, are difficult to avoid. Over the past three decades, with the development of clinical trials of traditional Chinese medicine (TCM) in China, TCM has been found to have good effects on improving heart function, protecting the myocardium, and treating and preventing arrhythmia and reperfusion injury. In the proposed systematic review, we aim to evaluate the efficacy and safety of adding TCM to standard Western medicine for treating patients with ACS. We present the following article in accordance with the PRISMA-P reporting checklist (available at http://dx.doi.org/10.21037/apm-21-681) (6).

Methods

Search strategy

A systematic search will be carried out in the China National Knowledge Infrastructure (CNKI; Chinese), the Chinese Biomedical Literature Disk Database (CBMdisc; Chinese), Wanfang Data (Chinese), PubMed, Embase, and Web of Science for relevant papers up to January 20, 2021. No restrictions will be set on language, sex, race, or course of disease. The search strategy is as follows: [(Acute Coronary Syndrome) or (ST Elevated Myocardial Infarction) or (Non-ST Elevated Myocardial Infarction) or (Angina, Unstable)] and [(Medicine, Chinese Traditional)]. Table 1 shows the detailed search strategy for PubMed. We will also review the relevant references for additional studies.

Table 1 Search strategy for the PubMed database
Full table

Selection criteria

The inclusion criteria include the following: (I) patients older than 18 years; (II) patients treated with conventional Western medicine (control group) and a combination of TCM and Western medicine (experimental group); (III) clear reporting of any of effective rates, cardiovascular function index (including left ventricular ejection fraction, early peak flow velocity, and thrombolysis in myocardial infarction) blood lipid levels (including total cholesterol, triacylglycerol, and low/high density lipoprotein), or the incidence of adverse cardiovascular events; and (IV) randomized controlled trials (RCTs). The exclusion criteria include the following: (I) reviews, case reports, editorials, or comments; (II) patients in the control group also receiving TCM; (III) patients with severe background diseases or malignant tumors.

Data extraction and quality assessment

Data, including first author’s name, year of publication, sample size, sex ratio, average age, background disease, TCM received, duration of treatment, and endpoints reported will be independently collected by 2 reviewers. The quality of enrolled studies will be assessed using version 2 of the Cochrane risk-of-bias tool for randomized trials (RoB 2) (7). A third reviewer will used to resolve any disagreements.

Statistical analysis

Meta-analyses will be performed if at least two enrolled trials report the corresponding outcomes. Differences will be tested using weighted mean difference (WMD) and relative risk (RR) with 95% confidence interval (CI). Intergroup heterogeneity will be tested using Q test, with I²<50% and P>0.05 indicating no significant difference. In case of significant heterogeneity, a random-effects model with the DerSimonian–Laird method will be used. Conversely, a fixed-effects model with the Mantel–Haenszel method will be used instead. Potential publication bias will be tested by performing funnel plots. Stability of results will be tested by performing sensitivity analyses through omitting each study sequentially. Finally, subgroup analyses will also be performed. All the above statistical analyses will be performed using Stata version 15.0 software (StataCorp).

Discussion

TCM has been proved to be an effective clinical practice in China, and in recent years, there is growing evidence that hypertension can be effectively controlled by TCM (8). Therefore, we hypothesis that TCM can be also used to treat ACS (9), but unfortunately, no relevant evidence is available now. We believe the proposed systematic review will be the first meta-analysis to evaluate the efficacy and safety of integrated traditional Chinese and Western medicine for ACS patients. Four steps will be strictly implemented to ensure the reliability of results. This review will provide further guidance for the clinical treatment of patients with ACS and offer patients more options to relieve their symptoms.

Acknowledgments

Funding: None.

Footnote

Reporting Checklist: The authors have completed the PRISMA-P reporting checklist. Available at http://dx.doi.org/10.21037/apm-21-681

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/apm-21-681). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

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