LAUSR

The developing zebrafish ventricle generates higher intraventricular pressure (IVP) with increasing stroke volume and cardiac output at different developmental stages to meet the metabolic demands of the rapidly growing embryo (Salehin et al. Ann Biomed Eng, 2021;49(9): 2080‐2093). To understand the changing role of the developing embryonic heart, we studied its biomechanical characteristics during in vivo cardiac cycles. By combining changes in wall strains and IVP measurements, we assessed ventricular wall stiffness during diastolic filling and the ensuing systolic IVP‐generation capacity during 3‐, 4‐, and 5‐day post fertilization (dpf). We further examined the anisotropy of wall deformation, in different regions within the ventricle, throughout a complete cardiac cycle.