RESUMEN
BACKGROUND: The myocardial extracellular matrix is believed to be central to the remodelling that takes place following myocardial infarction. The contribution of markers of collagen metabolism to this process remains less well understood. The present study examined the contribution of some of the markers of collagen metabolism in cardiac remodelling, as well as the effect of spironolactone on the remodelling process. OBJECTIVES: To investigate the pathological contribution of markers of collagen metabolism, including matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), type I collagen carboxyterminal telopeptide (ICTP) and procollagen type I carboxyterminal propeptide (PICP), in cardiac remodelling following ischemic cardiomyopathy, and to examine the pharmacoregulatory effects of spironolactone on collagen metabolism. METHOD: Eighty-six consecutive patients (62 men and 24 women) with chronic heart failure of ischemic etiology (patient group) and 25 age-matched controls were enrolled in the study. The subjects in the patient group were randomly assigned into a spironolactone or nonspironolactone group. Plasma levels of MMP-9, TIMP-1, ICTP and PICP were measured using ELISA and radioimmunoassay techniques. Furthermore, left ventricular diastolic diameter and ejection fraction were assessed using two-dimensional and Doppler echocardiography. RESULTS: The plasma concentrations of MMP-9, TIMP-1 and the MMP-9 to TIMP-1 ratio, as well as ICTP, were significantly increased in the patient group. The PICP to ICTP ratio in the patient group was significantly lower than that in the age-matched control subjects. After a follow-up period of 24 weeks, the PICP to ICTP ratio increased, and MMP-9, TIMP-1 and the MMP-9 to TIMP-1 ratio decreased in the spironolactone subgroup. CONCLUSIONS: Biomarkers of collagen degradation were elevated and correlated with depressed heart function; spironolactone may partially reverse the dysregulation in collagen metabolism.