Model of a heart (IMAGE) Norwegian University of Science and Technology Caption Håvard Dalen holds a plastic model of a heart that has been cut away so the interior chambers are visible. He holds a ultrasound probe against the model to show how it is typically held during use. Credit Photo: Nancy Bazilchuk Usage Restrictions Use only in association with articles about this research and with proper credit. License Original 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.