A computer controlled versatile pulse duplicator for precision testing of artificial heart valves.

K Schichl; K Affeld

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PubMed · 8125620

A computer controlled versatile pulse duplicator for precision testing of artificial heart valves.

K Schichl·K Affeld

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Abstract

Numerous devices and mock circulations have been described for the measurement of pressure loss, closure time, closing and leakage volumes and energy loss in artificial heart valves. However, all the devices have been troubled with difficulties in generating and assessing the precise flow through the valve, and problems in defining the arterial load, i.e. the artificial aorta. The new test device follows a radically different approach: a computer controlled piston forces the fluid through the test valve only--with no afterload. During systole, outflow follows a physiological curve which is identical for all types of heart valves of a given size. During diastole a mathematically defined physiological pressure difference curve is followed. Consequently, the measurements are independent of the individual machine, the lab where testing takes place, the scientist who executes the test, the time when measurements are taken and all other external influences.

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Equipment Design Heart Valve Prosthesis Hemodynamics Humans In Vitro Techniques Microcomputers Models, Structural Pulse Quality Control Journal Article Research Support, Non-U.S. Gov't

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K Schichl, K Affeld. 1993. A computer controlled versatile pulse duplicator for precision testing of artificial heart valves.. https://pubmed.ncbi.nlm.nih.gov/8125620/

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