What Do I Need to Know about Heart Valves?
The heart is vital to human survival and understanding how it works helps us to be healthy.Copyright 2009 Centers for Disease Control and Prevention http://www.cdc.gov/heartdisease/coronary_ad.htm
Students are presented with the unit's grand challenge problem: You are the lead engineer for a biomaterials company that has a cardiovascular systems client who wants you to develop a model that can be used to test the properties of heart valves without using real specimens. How might you go about accomplishing this task? What information do you need to create an accurate model? How could your materials be tested? Students brainstorm as a class, then learn some basic information relevant to the problem (by reading the transcript of an interview with a biomedical engineer), and then learn more specific information on how heart tissues work—their structure and composition (lecture information presented by the teacher). This prepares them for the associated activity, during which students cement their understanding of the heart and its function by dissecting sheep hearts to explore heart anatomy.
To begin the engineering design process, a number of steps are taken to learn as much as possible about a defined problem before beginning to develop solutions. This involves thinking about what is already known and what is necessary to find out, gathering information from multiple sources, and exploring this information so to gain a deeper understanding of all aspects of the problem.
Biomedical engineering involves developing and testing solutions to problems of the human body, in cells, or other biological systems. The heart is essentially a pump, and its valves act as controls to help ensure the correct direction and pacing of blood flow. If they do not work as intended, then blood flow through the heart is impeded. Thus, biomedical engineers need to understand how the heart and its valves work, including the physical properties of the valves; then they use that information to develop working models that mimic the behavior of human heart valves, and are suitable as artificial replacement valves.
After this lesson, students should be able to:
- Identify major structures of the human heart on diagrams and organic specimens.
- Describe the flow of blood through the human heart.
- Describe the structure and function of heart valves.