Disclosed below is a device comprising a base 112, polymer walls 105, comb fingers 104, groove/ridge architecture 107, metal film 108, comb buses 103, electrical ground electrode 109, and polymer well 101 for electrical and mechanical stimulation as well as for measuring of contractile force and conduction velocity of the cellular sheet/cluster 102 in response to mechanical and electrical stimulation of the cell source as it grows into a multilayer cellular sheet on the device. This allows cell sheets to be cultured and conditioned to be compatible with the patient's cardiac environment in vitro, prior to sheet release and implantation. Major innovative elements of this device include: real-time data for rich understanding of engineered tissues as they are grown, ability to expose engineered tissues to patient-derived stimuli (specifically localized electrical stimuli, mechanical stimuli, and micro-architecture), and the option to implant after characterization.
