Improvement in collagen metabolism after 12 weeks' cardiac resynchronization therapy in patients with ischaemic cardiomyopathy

Abstract

Objectives: To investigate the effects of cardiac resynchronization therapy (CRT) on collagen metabolism biomarkers and their relationship to cardiac function, in patients with ischaemic cardiomyopathy (ICM). Methods: Serum levels of matrix metalloproteinase (MMP)-9, tissue inhibitor of MMP-9 (TIMP-1), carboxyterminal propeptide of type I procollagen (PICP) and carboxyterminal telopeptide of type I collagen (ICTP) were quantified before and after 12 weeks' treatment, in patients with ICM receiving CRTand standard medical therapy (CRT group) or standard medical therapy alone (non- CRT group), and in controls. Cardiac function was measured echocardiographically. Results: MMP-9, TIMP-1, ICTP and the MMP-9/TIMP-1 ratio were significantly higher, and the PICP/ICTP ratio significantly lower, in patients with ICM (n1/427) compared with controls (n1/420). After 12 weeks' treatment, MMP-9, TIMP-1, ICTP and the MMP-9/TIMP-1 ratio were significantly higher, and the PICP/ICTP ratio significantly lower, in the non-CRT group (n=15) compared with the CRT group (n=12). The PICP/ICTP ratio correlated positively with TIMP-1 and negatively with MMP-9. The early/atrial ratio and left ventricular ejection fraction correlated positively and negatively, respectively, with the MMP-9/TIMP-1 ratio. Echocardiographic measurements of cardiac function were significantly worse in patients with ICM compared with controls and improved significantly after treatment in the CRT group. Conclusions: In ICM, collagen degradation biomarkers were elevated and correlated positively with cardiac function. CRT partially reversed the deterioration in collagen metabolism and enhanced cardiac function. © The Author(s) 2013.