Plasma matrix metalloproteinase-9 level in prediction of myocardial fibrosis improved by magnetic resonance imaging in patients with hypertrophic cardiomyopathy

Objectives: This study aimed to compare plasma matrix metalloproteinase-9 (MMP-9) levels of hypertrophic cardiomyopathy (HCM) patients with and without fibrosis. Patients and methods: Fifty-three HCM patients (33 males, 20 females; mean age: 52.4±10 years; range, 42 to 63 years) diagnosed by transthoracic echocardiography and cardiac magnetic resonance imaging (CMR) between January 2015 and March 2018 were included in the prospective study. They were divided into two groups according to CMR: patients with and without fibrosis. Plasma MMP-9 levels were compared. Results: In this study, serum MMP-9 levels were significantly higher in HCM patients with myocardial fibrosis in CMR than those without fibrosis (p<0.001). Left ventricular mass index (OR=1.056, 95% CI: 1.004-1.112, p=0.035) and MMP-9 levels (OR=1.031, 95% CI: 1.013-1.049, p=0.003) were independent predictors of myocardial fibrosis. Conclusion: Serum MMP-9 level has high sensitivity and specificity for prediction of myocardial fibrosis on CMR in HCM patients. It is known that myocardial fibrosis is associated with major adverse cardiac events. Therefore, it would be appropriate to closely monitor HCM patients with high serum MMP-9 levels.