Date of Award
Dissertation - Restricted
Doctor of Philosophy (PhD)
James D. Horgan
Ramon L. Lange
Statement of Problem
Characterization of the cardiovascular system has been reviewed in cardiovascular research both from a theoretical approach and from a clinical approach for many years. Regardless of the approach and the end result is hopefully a clearer understanding of the functioning of the heart and the circulatory system with an eventual application of this knowledge to the cardiovascular patient.
Cardiovascular diseases are responsible for a large number of deaths each year. Because of these statistics, there are hundreds of coronary care units throughout the world, and many more are in various stages of development. Despite significant advances in cardiology, death from acute myocardial infarction has remained relatively unaltered. Approximately 30 per cent of those hospitalized with an acute attack succumb to their illness. (1)
It is the obligation of today's medical researchers to bring the vast amount of technology gained from other engineering and scientific ventures to bear upon the problems in medicine. At the present, there exists the technical capabilities to measure and present cardiac patient data in an on-line fashion: the proper use and interpretation of this information can improve cardiovascular disease diagnosis and prognosis. Figure 1-1 depicts the "information flow" in a typical coronary care unit. The four blocks represent the main areas of concern in cardiovascular health care.
It is equally important to choose the most beneficial patient information and to reject ambiguous and redundant parameters. Thus, one must be able to assess measured variables as they pertain to cardiovascular function. To realize the difficulty of this objective the author has detailed the block in Figure 1-1 marked "cardiovascular patient" and presented it in Figure 1-2. This figure includes the most important internal and external feedback control systems and extracardiac factors impinging upon the heart and demonstrates the complexity of the cardiac control system.
Unlike a well designed engineering control system which is completely controllable, completely observable and can be completely defined by state variables, the cardiovascular system is neither completely controllable nor observable and remains to be completely defined.
The objective of this research is the quantitative assessment of the human cardiovascular system. The cardiovascular system will be investigated from both a theoretical approach and a clinical approach.