RESUMO
Background: Chronic total occlusion (CTO) is an angiographic picture of total occlusion without blood flow which is estimated to have lasted at least 3 months. This study attempted to provide an overview of the levels of matrix metalloproteinase-9 (MMP-9), soluble suppression tumorigenicity 2 (sST2), and N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) as remodeling, inflammatory, and atherosclerotic markers, as well as changes in the angina severity in patients with CTO who underwent percutaneous coronary intervention (PCI) compared to those without PCI. Methods: This study is a preliminary report with quasi-experimental design study with a pre-test and post-test approach to compare PCI's effect in CTO patients towards changes in MMP-9, sST2, NT-pro-BNP levels, and changes in the angina severity. Twenty subjects underwent PCI and 20 subjects with optimal medical therapy, who were then assessed at baseline and 8 weeks after intervention. Results: The results of this preliminary report showed that decreased MMP-9 (pre-test: 12.07 ± 1.27 ng/mL vs. post-test: 9.91 ± 5.19 ng/mL, P = 0.049), sST2 (pre-test: 37.65 ± 20.00 ng/mL vs. post-test: 29.74 ± 15.17 ng/mL, P = 0.026) and NT-pro-BNP (pre-test: 0.63 ± 0.23 ng/mL vs. post-test: 0.24 ± 0.10 ng/mL, P < 0.001) levels were found after 8 weeks of PCI compared to those without such intervention. The levels of NT-pro-BNP were lower in the PCI group (0.24 ± 0.10 ng/mL) than in the non-PCI group (0.56 ± 0.23 ng/mL; P < 0.001). Moreover, there was an improvement of angina severity in PCI group than without PCI (P < 0.039). Conclusions: Although this preliminary report found a significant decrease in MMP-9, NT-pro-BNP, and sST2 levels in CTO patients who had undergone PCI compared to those without PCI, as well as improved angina severity in these patients, this study still has limitations. The number of samples was so small that similar studies with larger sample sizes or multicenter investigations are required to deliver more trustworthy and useful results. Nevertheless, we encourage this study as a preliminary baseline for further studies in the future.
