[Experimental study of the hydrodynamics of polyurethane tricuspid heart valves]

Photochromic imaging, a new experimental hydrodynamic method, was used to study the flow structure behind polyurethane cardiac valve implants. The method is based on the sensitivity of model physiological medium to laser radiation. Color labels appear in 10-6 sec in the flow behind the valve under exposure to laser radiation. The motion of color labels in the flow is recorded with a high-speed camera. This makes it possible to determine the flow structure behind the valve. The flow structure behind three types of polyurethane cardiac valve implants was experimentally studied under conditions of model physiological flow. A polyurethane tricuspid valve with inner diameter 24 mm, a polyurethane tricuspid valve installed in a polyurethane tube, and a polyurethane tricuspid valve installed in a housing with Valsalva sinuses were studied. Complex flow structure was observed behind the cardiac valves. The complexity of its structure is explained by specific properties of valve construction. Flow rate profiles were determined for each moment of valve operation. These profiles show the dynamics of flow structure behind the valves.