Fig 2. Electro-functional analysis of engineered heart tissue constructs.

A) Schematic illustration of the experimental design and engineered heart tissue (EHT) model. B) ET (excitation threshold), MCR (maximum capture rate) and AC (amplitude of contraction) of the constructs before and after addition of MSCs were measured. Constructs with similar number of rat cardiomyocyte/cardiac fibroblast (rCM/cFb) were used as control (+rCM/cFb group). Addition of human dermal fibroblasts turned constructs into non-beating (NB) patches. Addition of MSCs either mono-cultured in plates (2D) or collagen patches (3D) or co-cultured with rCM/cFb in plates did not affect the functional parameters of the constructs (n = 4–8). Error bars represent SEM.