A biocompatible flow chamber to study the hemodynamic performance of prosthetic heart valves

The goal of this study was to design, fabricate, and characterize a biocompatible flow chamber to study the performance of artificial heart valves. The system consists of a testing fluid chamber and a water chamber (separated by a latex diaphragm), following the design of a left ventricular assist device. Two St. Jude bileaflet mechanical heart valves were placed oppositely in the testing fluid chamber to control flow direction. The flow rate of the testing fluid chamber was set at 5.6 L/min, with a stroke volume of 80 ml. The performance of the system was examined through three-dimensional numerical simulation and in vitro experiments with whole blood and washed platelets. Hemolysis was measured with whole blood using a spectrophotometer. Platelet activation was measured by platelet surface P-selectin expression using flow cytometry. The three-dimensional computational fluid dynamics model demonstrated that the flow field in the chamber was laminar and physiological. Results from in vitro experiments indicated that the flow conditions in the chamber did not induce hemolysis or platelet activation with the presence of St. Jude heart valves. Overall, the flow chamber can provide a feasible environment to study the hemodynamic performance of artificial heart valves.