Relationship Between Serum Matrix Metalloproteinase and Myocardial Fibrosis Detected with Cardiac MRI in Heart Failure Patients with Reduced Ejection Fraction

OBJECTIVE: A strong correlation exists between myocardial fibrosis and heart failure (HF). Myocardial fibrosis can be detected by cardiac magnetic resonance (CMR), which is a crucial noninvasive imaging method with high specificity and sensitivity. Matrix metalloproteinases (MMPs) are primary proteases responsible for the degradation of extracellular matrix (ECM) components, and they play a vital role in maintaining the balance between anabolism and catabolism of ECM. This study aims to investigate the correlation between cardiac fibrosis detected on CMR and serum MMP-9 levels in patients with HF. METHODS: We enrolled 53 patients (age: ≥18 years) with left ventricular ejection fraction (LVEF) ≤40%, who received CMR because of various indications. All patients were divided into two groups-with cardiac fibrosis (n=32) and without cardiac fibrosis (n=21)-detected by CMR with late-Gadolinium. Both groups were then compared according to MMP-9 levels. RESULTS: MMP-9 levels were significantly higher in patients with cardiac fibrosis than those without fibrosis (p<0.01). A correlation was determined between the diffusiveness of fibrosis and serum MMP-9 levels. Besides, a statistically significant correlation was determined between MMP-9 measurements and the number of segments with fibrosis (p<0.05). In the group with cardiac fibrosis, LVEF measurements by CMR were significantly lower (p<0.01), with left ventricular end-diastolic volume (LVEDV) and left ventricular end-systolic volume (LVESV) measurements significantly higher (p<0.01), than the other group. Furthermore, we found a statistically significant correlation between MMP-9 levels and LVEDV and LVESV. CONCLUSION: MMP-9 levels correlate with cardiac remodeling in patients with HF and could be useful in predicting left ventricular fibrosis. In clinical practice, the use of serum MMP-9 could provide early consideration of therapies for structural and functional pathology of the heart in patients with HF.