SDC4 and familial dilated cardiomyopathy: Importantly, serum syndecan-4 showed comparable levels in patients with cardiomyopathies of different etiologies, i.e., inflammatory vs. non-inflammatory DCM, myocarditis, pericarditis and perimyocarditis, and following MI, indicating that syndecan-4 has limited value as a clinical circulating biomarker of cardiac inflammation.