Assignment 6: Design of a Muscle Testing Apparatus

Due: Thursday March 10th at the beginning of class

In this project you will perform the preliminary investigation that would be needed in preparation for a design project that aims to construct an apparatus for testing some aspect or aspects of cardiac muscle mechanics. Note that a variety of different approaches have been used to measure a variety of different mechanical properties in cardiac muscle obtained from a variety of different preparations. No one system is suitable for making all the possible mechanical measurements or for use in all the possible tissue or heart preparations that have been used. Part of your task will be to review the literature to decide what properties and what preparations you will focus on.

  1. Find one or more published journal articles describing a particular cardiac muscle testing system. Provide a complete reference including the PMID if it has one. Note that many of the most detailed papers in this field were published in the 1980s or even earlier so they might not be available online. Expect to spend time in the library. Typical journals may include the Journal of Biomechanics, the Annals of Biomedical Engineering, the ASME Journal of Biomechanical Engineering, the IEEE Transactions on Biomedical Engineering, Biophysical Journal, and the American Journal of Physiology: Heart and Circulatory Physiology.

  2. Identify what kinds of mechanical measurements the system can and can not make and what kinds of cardiac muscle preparations it is designed to test. For example, does it measure active contractile properties or only passive resting properties? Is it uniaxial or multi-axial? Will it work for tissues from many sources or is it fairly specific to particular preparations from particular species? Is it designed to test isolated cells, isolated muscle or whole hearts?
  3. Explain why you think these particular measurements and preparations will be useful, and what limitations they will have?
  4. Summarize the major components of the apparatus and how they work together. Use your own words and an original diagram or sketch.
  5. Identify key specifications of the components such as the sensitivity of the transducers. How accurate and reproducible are the measurements, and would greater accuracy or reproducibility be helpful?
  6. Are there newer technologies that would make the design, faster, more accurate, more reliable, easier to use, cheaper, or better in other respects? Summarize and explain.
  7. What kind of analysis is done on the measurements to deduce useful properties of cardiac muscle? Provide a brief flowchart or pseudocode for a computer program that would perform an appropriate or better analysis.