Computational model of μtissue mechanics. (A) Representative finite element mesh of μtissue (cell–cell junction highlighted in red). (B and C) Predicted patterns of local traction (B) and cellular (C) stress at peak systole for homogeneous (i) and heterogeneous (ii) pairs. The red arrow indicates high traction stress beneath the neonate myocyte near the cell–cell junction. (D) Predicted traction force and percentage shortening in heterogeneous cell pairs. (E) Schematic illustration indicates typical tension experienced at substrate adhesions within pairs of neonate cells (i) and heterogeneous (ii) µtissues.