EDN1 and systemic sclerosis: Regarding right heart involvement only serum concentration of the pro-brain natriuretic peptide N-terminal fragment (nT-proBNP) and ET-1 have been found to be higher in SSc patients compared to HCs, while no difference was found with asymmetric dimethylarginine (ADMA), sENG and human tissue inhibitor of Matrix Metalloproteinase (TIMP-1) concentrations.