Efficacy of Riociguat in cronic thromboembolic pulmonary hypertension: Meta-analysis study

Objective: Riociguat is a drug approved by the World Health Organization (WHO) for the purpose of improving the hemodynamic parameters and increasing exercise capacity of patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are not suitable for surgery or who have persistent or relapsed postoperatively. In this study, it is aimed to investigate the efficacy of Riociguat in patients diagnosed with CTEPH by meta-analysis method. Randomized controlled trial studies have been conducted on the drug, and the drug's efficacy and long-term results have been demonstrated in a series of articles. The designs of these studies are comparisons of two independent groups given the drug and placebo. In the meta- analysis study, studies with a dependent group design in which changes in mPAP, PVR, CO, and 6MWD parameters were observed before and after medication in patients diagnosed with CTEPH were examined, and the difference between pre-post means for these parameters, the Mean Difference (MD) value, is the summary statistic to be combined with the meta-analysis. . Although there are meta-analysis studies on the efficacy of Riociguat on PAH in the literature review on the subject, no meta-analysis study was found in which prospective clinical studies were evaluated on CTEPH. This study is the first in the literature in terms of its hypothesis. Method: Articles containing the keywords "Riociguat" and "chronic thromboembolic pulmonary hypertension" together in their titles in PubMed, Web of Science, Scopus and ScienceDirect databases, without any time and language restrictions, until May 2022, in order to test the hypotheses created by meta- analysis. scanned. As a result of the literature review, it was determined that there were 669 articles. By examining all these articles in detail, 6 studies were identified that could yield data compatible with the hypothesis of the meta-analysis. Results: Based on the result of the mPAP variable combined with the meta-analysis of 654 patients, Riociguat lowers the mPAP value by an average of 9.11 br. Combined with the meta-analysis of 523 patients for the PVR variable, Riociguat reduces PVR by an average of 223.47 br. Based on the result of the CO variable combined with the meta-analysis of 587 patients, Riociguat increases the CO value by an average of 0.49 br. Based on the result of the 6MWD variable combined with the meta-analysis of 496 patients, Riociguat increases the 6MWD distance by an average of 39.14 m. All results are statistically significant. Conclusion: It can be said that positive results were obtained in terms of related parameters in patients diagnosed with CTEPH with the use of Riociguat. Keywords: Meta-analysis, Riociguat, Chronic thromboembolic pulmonary hyperte