The prognostic value of circulating markers of collagen turnover after acute myocardial infarction

We assessed the time profiles and prognostic utility of circulating markers of collagen turnover (CTO) following acute myocardial infarction (MI). In contrast to previous studies, no patient had been pre-treated with inhibitors of the renin-angiotensin-aldosterone system (RAAS) at the time of initial assessment.Plasma levels of N-terminal fragment of type I collagen (PINP), carboxy-terminal telopeptide of type I collagen (ICTP), N-terminal fragment of type III collagen (PIIINP), matrix metalloproteinase-1(MMP-1) and tissue inhibitor of MMPs type-1 (TIMP-1) were assessed in 233 patients following acute MI. The CTO markers were initially assessed prior to treatment by either captopril or losartan, at a median of 3 days following MI. In addition, blood samples were acquired at 1 month, 1 year and 2 years following MI. Development of heart failure symptoms, all-cause and cardiovascular death were recorded as endpoints during two years of follow-up.With the exception of PIIINP, all CTO markers demonstrated significant longitudinal changes following MI. At baseline, ICTP (p0.0001) and TIMP-1 (p=0.01) levels were significantly elevated in patients who later died compared with survivors. In multivariable analysis only ICTP reached statistical significance as predictor of all cause death (p=0.048). In patients developing symptoms of heart failure during follow-up, ICTP was the only significantly elevated CTO marker (p0.01).The present study supports a prognostic role for ICTP in both the acute and chronic phase following MI.