Cardiac fibrosis typically arises as a result of myocardial infarction, causing the irreversible loss of billions of cardiomyocytes and progressive heart failure. New regenerative medicine approaches are under investigation to reduce heart failure or revert cardiac fibrosis. In vitro testing platforms able to mimic the mechanical behavior of pathological cardiac tissue allow to reduce in vivo trials on animal models in agreement with the 3Rs principle. State of the art literature reports in vitro models mainly based on hydrogels, which however have different drawbacks: they lack structural biomimetic cues for cell guidance, cannot bear the cyclic deformations of cardiac tissue and have short degradation times (< 1 month).