To preliminarily evaluate if ED-A+ Fn might be a promising novel serum biomarker of pathologic cardiac tissue remodeling, we determined serum concentrations in patients suffering from heart failure (n = 114) due to different etiologies in comparison to serum samples from 12 healthy volunteers (mean age: 35 years; 75% male and 25% female) without any known cardiovascular pathology. Here, FN1 is linked to heart failure.