Abstract 4335: Serum Profiles of Matrix Metalloproteinases in the Coronary Sinus in Patients with Nonischemic Dilated Cardiomyopathy: Relationship with Left Ventricular Performance
Matrix metalloproteinases (MMPs) contribute to myocardial extracellular matrix degradation during the remodeling process in the failing heart. Recent studies have shown that circulating MMPs are closely associated with left ventricular (LV) remodeling and adverse cardiac events in patients with nonischemic dilated cardiomyopathy (DCM). However, there is little direct evidence documenting the profiles of MMPs in the coronary sinus (CS) in DCM. We aimed to evaluate the relationship between serum levels of MMPs in the CS and the LV performance in patients with DCM. We measured serum levels of MMP-2, MMP-3, and MMP-9 in the aortic root (Ao) and the CS using ELISA in 45 patients (mean age 59 ±13 years, 38 males) with DCM. Serum levels of N-terminal-pro-B-type natriuretic peptide (NT-proBNP) in the Ao and the CS were also measured. The LV volume and function were also assessed using echocardiography. Serum levels of MMP-2 and MMP-3 were significantly higher in the CS than those in the Ao (MMP-2, 832 ±226 vs. 809 ±213 ng/ml, p=0.015; MMP-3, 66.9 ±50.7 vs. 61.9 ±48.5 ng/ml, p=0.023), whereas there was no difference in serum levels of MMP-9 between the Ao and the CS. The level of MMP-3 in the CS was significantly correlated with the level of MMP-2 in the CS (r=0.42, p=0.014) or the value of early diastolic peak E velocity / early diastolic mitral annulus velocity (r=0.43, p=0.017). Moreover, there was a significant positive correlation between serum MMP-2 levels and NT-proBNP levels in the CS (r=0.48, p=0.006). Our results demonstrate the secretion of MMP-2 and MMP-3 from the failing heart in DCM, and indicate that the levels of MMP-2 and MMP-3 in the CS may be closely associated with the LV performance in patients with DCM.