The tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitor of matrix metalloproteinases (MMPs). MMPs/TIMPs balance is well known to play important roles in myocardial remodelling regulation. TIMPs biological role suggests that an up-regulation leads to extracellular matrix accumulation, whereas a down-regulation results in an increased matrix proteolysis. TIMPs are also able to influence cardiomyocyte hypertrophy and/or hypertrophic remodelling of the myocardium.

We aimed to determine whether circulating tissue inhibitor of MMPs (TIMP-1 and TIMP-2) could be a prognostic biomarker in patients with hypertrophic cardiomyopathy (HCM).

Twenty-one HCM patients and twenty-two age-matched non-HCM (aged: 46±14), plasma level of TIMP-1 and TIMP-2 were assayed by ELISA (Enzyme Linked Immuno Sorbent Assay) Sandwich-type. To assess the predictive accuracy of biomarkers we performed the Receiver Operating Characteristic (ROC) curve analysis. The 95% confidence interval (CI) has been also calculated for sensitivity and specificity.

Levels of TIMP-1 were significantly higher in HCM patients than non-HCM (62.50±57.44 vs. 28.73±11.70ng/ml; P=0.017). There was no significant difference for circulating TIMP-2 level. Higher TIMP-1 levels correlated negatively with left ventricular mass (r=−0.566; P=0.018) and intraventricular septum thickness (r=−0.604; P=0.008). ROC curve analysis showed that plasma TIMP-1 achieved a good predicting performance of HCM with an area under curve (AUC): 0.733, 95% CI: 0.573−0.893, P=0.013. The predictive value of TIMP-1 was>47.5ng/ml with a good specificity of 93.75% and a quite modest sensitivity 40%.

Our findings do suggest that TIMP-1 may be a useful prognostic biomarker that could discriminate hypertrophic cardiomyopathy presence.