As a pilot project within the Heart-on-Chip program hDMT is working on the so-called Cytostretch device, which is capable of mechanically stimulating heart muscle cells (cardiomyocytes). It will be used for screening new drugs at an early stage of their development for possible side-effects that cause lethal arrhythmias. Unexpected cardiotoxicity is one of the major reasons why new drugs are withdrawn from the market, as currently available in vitro model systems and animal models fail to reliably predict the effects in the human body.
The cardiomyocytes are cultured in a nutritious solution on top of a thin stretchable silicon membrane containing stretchable electrodes for measuring and applying electrical signals. By designing micropatterns on the surface of the membrane it is possible to align the cells in a specific direction. The electrodes are able to register the electrical activity and contraction of the heart cells while being subjected to a compound. By stretching the membrane it is possible to simulate strenuous physical activity, which often is the cause of arrhythmia, thus creating an accurate model of the human heart under exercise conditions. The Cytostretch can be used for high throughput compound library screening. In addition, other complementary 3D models are being developed.