Patent attributes
Two-way, three-position and one-way, two-position slit valves in cardiovascular access catheters with closed distal ends have slit geometries configured to overcome adhesion between opposed abutting slit faces, when pressure differentials are applied between the interior and the exterior of the catheter. Portions of the slit are oriented at a non-zero angle relative to the longitudinal axis of the catheter causing shear forces to be generated in abutting slit faces. Shear forces arise from tangential, radial, or longitudinal stresses generated in the catheter body. Slit geometries are planar or curved or include multiple end-to-end connected slit subsections. If a slit partially circumscribes a portion of the adjacent outer wall of the catheter body, restraint to outward and inward movement on that portion is reduced. Slit valves are configured to open inwardly to aspirate fluids, to open outwardly to infuse fluids, or both.
