Three-Dimensional Printing of Soft and Stretchable Bio-electronic Cardiac Patch

Cardiovascular diseases in general and myocardial infarction (MI) in particular, are one of the main causes of death in developed countries. MI results from the blockage of the coronary artery leading to ischemia and death of contractile cells, resulting in chronic cardiac dysfunction. Currently, the only treatment for end-stage heart failure is cardiac transplantation. However, cardiac donors are scarce and many patients are dying while on the waiting list. Tissue engineering offers an alternative solution by generating functional substitutes for the injured myocardium. Recently, our lab developed a new concept in tissue engineering, where built-in electronics can accurately regulate its own electrophysiological function over time, and at the same time report it and automatically activate regenerative processes. However, the mechanical properties of the electronic system did not match those of the tissue. To fabricate the cardiac patches with soft electronics, we used a three-dimensional (3D) bio-printer. We simultaneously 3D printed rat neonatal cardiomyocytes, dispersed in ECM-based hydrogel and a conducting formulation of electrodes. Preliminary results showed that the printed electrodes can record the function of the printed tissue and at the same time provide electrical stimulation for the regulation of the patch’s function.