Heart Valve Case Study

Length: 2 weeks (introductory lecture, independent study and presentations)

Aims: To consider the various factors involved in the design, materials selection and production of a heart valve and to help you to acquire deductive reasoning skills and teamwork skills by working as part of a team.

Key Skills:  Group working, independent study, written and oral communication, and organisation.

Assessment: Group report and group presentation



This is a group-based case study that examines the various factors involved in the design, materials selection and production of an artificial heart valve. At the end of this case study, students should be able to:

  • Identify the critical design and property requirements, and explain why they are critical.
  • Describe the replacement valve design options currently available.
  • Compare and contrast the relative merits of natural tissue/organ modified valves and synthetic material/fabricated valve
  • Identify the critical factors limiting their optimal functioning and longevity.

After an introductory lecture, you will be assigned to your groups. Each group should elect a group co-ordinator who is responsible for co-ordinating the activities of the group. Within the group, members will choose one of the following work tasks:

  • Design Function
  • Materials Selection
  • Materials Processing
  • Materials Properties
  • Component Performance
  • Component Reliability
  • Other relevant issues such as Specific Biocompatibility/Cost etc.

Groups, and individuals within each group, are expected to organise themselves to gather any relevant information using the Internet, Libraries, Lecture notes etc. plus other resources they locate using their own initiative.

Assessment

Each group must submit a single written report (60% of student’s marks) summarising their main findings and conclusions drawn (tips for writing reports). The report is to be a maximum of 4 sides of A4 of word-processed text.

Each group also needs to prepare a group oral presentation (30% of student’s marks). The group co-ordinator should present the introduction and conclusions. The sub-group members within each group should decide who should give presentations. OHPs or PowerPoint should be used to summarise the information that is presented – reading notes will not be acceptable. OHPs/OHP pens should be obtained from the dental school. The presentations will be assessed in terms of: Content 15%; Presentation 15%. (tips for giving an effective presentation)

Each group will be required to assess the presentations of the other 3 groups for Content (marks out of 10) and Presentation (marks out of 10) using the mark sheet provided. Excessively high or low marks, or median marks for Content and Presentation for each group, will be subject to moderation both ways! So, please take the exercise seriously and assess the presentations as objectively as humanly possible.

Finally, groups are expected to carry out peer assessment of individual contributions to the case study (10% of student’s marks). Each group must agree marks for each team member’s contribution to:

  • Ideas on how to conduct the case study
  • Obtaining relevant information
  • Analysing information obtained
  • Preparing the written report
  • Preparing the presentation.

Resources

1. Some Web Sites to visit:

http://www.csmc.edu/heartcenter/images/Heart_Valves.pdf

http://www.hia.rwth-aachen.de/indexE.html

http://www.medtronic.co.uk/cardiac/heartvalves/prodinfo.html

http://www.atsmedical.com/product.html

http://www.sjm.com/products/intlproducts.shtm#heartvalves

http://www.lbl.gov/Ritchie/Programs/BIO/valve.html

http://www.mcritx.com/

http://www.americanheart.org/presenter.jhtml?identifier=10000056

http://www.heartlab.rri.on.ca/heartlab.html

2. Some Scientific Journal articles to attempt to find and read:

Bhuvaneshwar, G. S., Muraleedharan, C. V., Ramani, A. V., et al. (1991) Evaluation of materials for artificial heart valves, B Mater Sci 14 (6) p1363-1374.

Bolz, A., Schaldach, M., Winter, W. (1990) Mechanical aspects of the development of artificial-heart valves, Biomed Tech 35 (12) p302-315.

Tatarinov, V. F., Zolkin, P. I. (1999) Advances in the material of carbon glass-ceramic materials for artificial heart valves, Refract Ind Ceram 40 (3-4) p118-119.

Macnair, R., Underwood, M. J., Angelini, G. D. (1998) Biomaterials and cardiovascular devices, P I Mech Eng H 212 (H6) p465-471.

Bjork, V. (1989) Development of mechanical heart-valves – past, present and future, Can J Cardiol 5 (1) p64-73.

Cao, H. C. (1996) Mechanical perfomance of Pyrolytic carbon in prosthetic heart valve applications, J Heart Valve Dis 5 (S32-S49).

Schoen, F. J., Levy, R. J. (1999) tissue heart valves: Current challenges and future research perspectives, J Biomed, Mater Res 47 (4) pp439-465.

Schoen, F. J. (1999) Future directions in tissue heart valves: Impact of recent insights from biology and pathology, J Heart Valve Dis 8: (4) pp350.

Ma, L., Sines, G. H. (1999) Unalloyed pyrolytic carbon for implanted mechanical mechanical heart valves, J Heart Valve Dis 8 (5) pp578-585.

N.B. If any of these or other relevent papers/articles are found and referred to, then a full copy of the paper/article MUST be attached to your written report. Other scientific papers of relevance can be located by doing a World of Science Web computer search (get your login details from the Dental School) and checking the UoB Library on-line TALIS Catalogue System for journals and monographs etc.

General information sources:

New Scientist

Scientific American

Nature

Daily Newspaper Achives

CNN

Try searching their Web Sites

N.B. If any relevant papers/articles are referred to. Then a full photocopy of the paper/article must be attached to your written report.