AimsMyocardial collagen metabolism can be assessed indirectly by circulating biomarkers. We aimed to examine associations between myocardial collagen type I synthesis and degradation, and echocardiographic, clinical, and B-type natriuretic peptide (BNP) findings in heart failure.MethodsWe studied 57 women and 75 men 60 years or older with systolic heart failure (New York Heart Association II-IV and an ejection fraction 45%). Mean age was 75 years, blood pressure 134/80mmHg, ejection fraction 34%, and median BNP 210ng/l. Analyses of the carboxy-terminal propeptide of procollagen type I (PICP, biomarker of collagen type I synthesis) and the serum carboxy-terminal telopeptide of collagen type I (CITP, biomarker of collagen type I degradation) were measured. Extensive echocardiographic examinations were performed, including variables of dyssynchrony.ResultsIncreased collagen synthesis (PICP) was independently related to increased BNP levels (r=0.24, P=0.018). Furthermore, independent associations were found between PICP and left ventricular size, isovolumic relaxation time, and relative wall thickness. Increased collagen degradation (CITP) was independently related to increased BNP levels (r=0.35, P<0.001). Also, univariable, but not multivariable, associations were found between CITP and E/E' septal and QRS duration.ConclusionBiomarkers of collagen type I synthesis and degradation are independently related to BNP and to indices of left ventricular size and diastolic function in systolic heart failure. It is proposed that BNP may contribute to alterations in collagen type I metabolism in systolic heart failure.