Background/objective: Ischemic heart disease is a major cause of mortality worldwide. Myocardial tissue engineering aims to create transplantable units of myocardium for the treatment of myocardial necrosis caused by ischemic heart disease - bioreactors are used to condition these bioartificial tissues before application.
Methods: Our group developed a multimodal bioreactor consisting of a linear drive motor for pulsatile flow generation (500 ml/min) and an external pacemaker for electrical stimulation (10 mA, 3 V at 60 Hz) using LinMot-Talk Software to synchronize these modes of stimulation. Polyurethane scaffolds were seeded with 0.750 × 106 mesenchymal stem cells from umbilical cord tissue per cm2 and stimulated in our system for 72 h, then evaluated.
Results: After conditioning histology showed that the patches consisted of a cell multilayer surviving stimulation without major damage by the multimodal stimulation, scanning electron microscopy showed a confluent cell layer with no cell-cell interspaces visible. No cell viability issues could be identified via Syto9-Propidium Iodide staining.
Conclusions: This bioreactor allows mechanical stimulation via pulsatile flow and electrical stimulation through a pacemaker. Our stem cell-polyurethane constructs displayed survival after conditioning. This system shows feasibility in preliminary tests.
Keywords: Bioreactors; heart disease; myocardium; stem cells; tissue engineering.