Heart on a Chip (VIDEO) University of California - Berkeley This video is under embargo. Please login to access this video. Caption Shown is human heart tissue, derived from adult stem cells, before and after exposure to isoproterenol, a drug used to treat bradycardia (slow heart rate) and other heart problems. The beat rate visibly increased after 30 minutes of exposure to the drug. Credit Video by Dr. Anurag Mathur/Healy Lab Usage Restrictions All rights reserved License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.