System for evaluation of prosthetic heart valves under steady hydrodynamic conditions

A process implemented by a computer system for automatically controlling a test system for measuring steady flow hydrodynamic performance of a valved prosthesis in both forward fluid flow and reverse fluid flow directions without adjustment of the valved prosthesis within or removal of the valved prosthesis from the test conduit, the process comprising the following operations performed by the computer system:

• directing the controller in control communication with a first valve downstream of the fluid pump to configure the first valve to direct flow of the working fluid from the fluid pump through a test conduit holding the valved prosthesis in-line with fluid flow in a forward flow direction from a proximal end of the test conduit to a distal end of the test conduit;
• directing a controller in control communication with a fluid pump to instantiate pumping of a working fluid from a reservoir in the test system by the fluid pump;
• receiving from the controller measurement values of a flow rate of the working fluid in the test system sensed by a flow rate sensor in the test system in data communication with the controller;
• directing the controller to adjust a pump rate of the fluid pump to achieve a stable target flow rate of the working fluid through the test system based upon the flow rate measurement values received by the controller;
• receiving from the controller measurement values of pressure drop through the valved prosthesis within the test conduit while the working fluid flows in the forward flow direction as sensed by a pressure sensor in the test system in data communication with the controller;
• directing the controller to stop the fluid pump and reconfigure the first valve to direct flow of the working fluid through the test conduit and the valved prosthesis in a reverse flow direction from a distal end of the test conduit to a proximal end of the test conduit;
• directing the controller to reinstantiate pumping of the working fluid from the reservoir by the fluid pump;
• receiving from the controller measurement values of a pressure differential across the valved prosthesis within the test conduit as sensed by the pressure sensor;
• directing the controller to adjust a pump rate of the fluid pump to achieve a stable target differential pressure of the working fluid across the valved prosthesis based upon the measurement values of the pressure differential;
• and
• receiving from the controller measurement values of leakage flow through the valved prosthesis sensed by a flow rate sensor in the test system in data communication with the controller while the working fluid flows in the reverse direction.

A method of operating a test system for measuring steady flow hydrodynamic performance of a valved prosthesis, the method comprising

• pumping a working fluid from a reservoir in the test system with a fluid pump;
• in a forward flow configuration,
• configuring a first valve in the test system to direct flow of the working fluid from the fluid pump through a test conduit holding the valved prosthesis in-line with fluid flow in a forward flow direction from a proximal end of the test conduit to a distal end of the test conduit;
• responsive to measurement values of a flow rate of the working fluid in the test system sensed by a flow rate sensor in the test system, adjusting a pump rate of the fluid pump automatically by a controller driving the fluid pump to achieve a stable target flow rate of the working fluid through the test system;
• responsive to a first test schedule automatically implemented in the controller, adjusting the pump rate of the fluid pump to change the flow rate to each of a plurality of prescribed flow rates according to the first test schedule;
• measuring with a pressure sensor in the test system a pressure drop across the valved prosthesis for each prescribed flow rate in the first test schedule;
• and
• recording, via the controller in communication with the pressure sensor, each measured pressure drop for each prescribed flow rate in the first test schedule;
• or
• in a reverse flow configuration,
• configuring the first valve in the test system to direct flow of the working fluid from the fluid pump through the test conduit holding the valved prosthesis in-line with fluid flow in a reverse flow direction from a distal end of the test conduit to a proximal end of the test conduit;
• responsive to measurement values of a differential pressure of the working fluid in the test system sensed by the pressure sensor, adjusting the pump rate of the fluid pump to achieve a stable differential pressure of the working fluid across the valved prosthesis in the test conduit;
• responsive to a second test schedule automatically implemented in the controller, adjusting the pump rate of the fluid pump to change the differential pressure across the valved prosthesis to each of a plurality of prescribed differential pressures according to the second test schedule;
• measuring with the pressure sensor a pressure differential across the valved prosthesis within the test conduit for each prescribed differential pressure in the second test schedule while the working fluid flows in the reverse flow direction;
• recording, via the controller in communication with a flow meter, a leakage flow rate for each measured pressure differential for each prescribed differential pressure in the second test schedule.