A COMPUTER-CONTROLLED VERSATILE PULSE DUPLICATOR FOR PRECISION TESTING OF ARTIFICIAL-HEART VALVES

Numerous devices and mock circulations have been described for the mea surement of pressure loss, closure time, closing and leakage volumes a nd energy loss in artificial heart valves. However, all the devices ha ve been troubled with difficulties in generating and assessing the pre cise flow through the valve, and problems in defining the arterial loa d, i.e. the artificial aorta. The new test device follows a radically different approach: a computer controlled piston forces the fluid thro ugh the test valve only - with no afterload. During systole, outflow f ollows a physiological curve which is identical for all types of heart valves of a given size. During diastole a mathematically defined phys iological pressure difference curve is followed. Consequently, the mea surements are independent of the individual machine, the lab where tes ting takes place, the scientist who executes the test, the time when m easurements are taken and all other external influences.