Table 1.

Reference cardiac tissue-like properties for biomimetic culture microenvironment.

Properties	Reference values in cardiac tissue	References
Human cardiac ECM composition	70% fibrillar collagen (collagen I and V), 20% basement membrane (collagen IV, laminin, agrin, perlecan, nidogen), 4% structural ECM (proteoglycans and fibrous glycoproteins), 3% matricellular components (collagen VI, fibronectin)	(22)
Stiffness	1–6 kPa (fetal); 10–15 kPa (adult); > 50 kPa (fibrotic)	(23)
Anisotropic ratio of stiffness	1.9–3.9	(24)
Cyclic mechanical deformation	1 Hz (in humans), 10% at early stage of diastole (stiffness: 10–20 kPa) up to 15–22 % at the end of diastole (stiffness: 50 kPa)	(24)
Electrical conductivity	0.57 S/m	(24)
Topographical cues	In native heart, myocardial fibers are arranged into distinct laminae (4–6 myocytes thick) separated by collagen-based ECM: helical-laminar assembly of hierarchically organized fibrillar structures.	(25)