Dynamic Reconfigurable Microvalve Protection Device

Abstract

An endovascular microvalve device for use in a vessel during a therapy procedure includes a catheter and a filter valve coupled to the catheters. The filter valve is dynamically reconfigurable to automatically block and permit fluid flow through a vessel based on a local fluid pressure conditions about the filter valve. In embodiments, the filter valve has a proximal end fixed to the catheter, and a distal end which may be movable over the catheter. The lumen of the inner catheter delivers a therapeutic agent beyond the valve. The device is used to provide a therapy in which a therapeutic agent is infused into an organ.

What is claimed is: 
     
         1 . An endovascular microvalve device for temporary use in a vessel of a patient during an intravascular procedure, the vessel having a vessel wall, comprising:
 a) a flexible catheter sized for introduction into the vessel, the catheter having a proximal end and a distal end, an outer surface, a lumen extending between the proximal and distal ends, and opening at a distal orifice; and   b) a filter valve having a proximal end and a distal end, the proximal end of the filter valve fixed to the outside of the catheter, and the distal end of the filter valve coupled at a collar that is longitudinally displaceable on the catheter relative to the proximal end of the filter valve and retained proximal of the distal end of the catheter,
 wherein once the filter valve is in a deployed state in the vessel, the filter valve is dynamically movable depending on local fluid pressure conditions about the filter valve, such that, 
 when the fluid pressure is higher on a proximal side of the filter valve, the filter valve assumes a first configuration with a first diameter smaller than the diameter of the vessel such that flow about the filter valve and through the vessel in a proximal to distal direction is permitted, and 
 when the fluid pressure is higher on a distal side of the filter valve, the filter valve assumes a second configuration with a second diameter relatively larger than the first diameter and in which the filter valve is adapted to contact the vessel wall to act as a barrier to flow about the filter valve and through the vessel in a distal to proximal direction. 
   
     
     
         2 . The device of  claim 1 , wherein the filter valve comprises a plurality of filaments that are biased to extend radially outward from the first catheter. 
     
     
         3 . The device of  claim 1 , wherein the filter valve has a proximal portion comprising a braided filamentary structure. 
     
     
         4 . The device of  claim 3 , wherein the filter valve has a distal portion comprising a braided filamentary structure. 
     
     
         5 . The device of  claim 3 , wherein the filter valve has a distal portion comprising a non-braided filamentary structure. 
     
     
         6 . The device of  claim 5 , wherein the non-braided filamentary structure is spirally wound. 
     
     
         7 . The device of  claim 1 , wherein the filter valve comprises a porous polymeric material over a proximal portion of the filter valve. 
     
     
         8 . The device of  claim 7 , wherein the filter valve comprises a porous polymeric material over a distal portion of the filter valve. 
     
     
         9 . The device of  claim 1 , wherein in the first configuration, the filter valve includes a distal face that is convex in shape, and in the second configuration, the distal face of the filter valve is planar or concave. 
     
     
         10 . The device of  claim 1 , further comprising a second catheter adapted to be longitudinally displaced over the flexible catheter to collapse the filter valve against the outer surface of the flexible catheter. 
     
     
         11 . The device of  claim 1 , further comprising one or more radiopaque markers provided to the distal end of the flexible catheter. 
     
     
         12 . The device of  claim 1 , wherein the flexible catheter includes a proximal hub adapted to be coupled to a pressurized infusion source. 
     
     
         13 . An endovascular microvalve device for temporary use in a vessel of a patient during an intravascular procedure, the vessel having a vessel wall, comprising:
 a) a flexible first catheter sized for introduction into the vessel, the catheter having a proximal end and a distal end, an outer surface, a lumen extending between the proximal and distal ends, and opening at a distal orifice;   b) a proximal hub coupled to the proximal end of the first catheter and adapted to be coupled to a pressurized infusion source;   c) a filter valve having a proximal end and a distal end, the proximal end of the filter valve fixed to the outside of the first catheter, and the distal end of the filter valve coupled at a collar that is longitudinally displaceable on the first catheter relative to the proximal end of the filter valve and retained proximal of the distal end of the first catheter; and   d) a second catheter adapted to be longitudinally displaced over the first catheter to collapse the filter valve from an open configuration to a collapsed configuration against the outer surface of the first catheter, the collar at the distal end of the filter longitudinally distally displacing along the first catheter when the filter valve is collapsed into the collapsed configuration.   
     
     
         14 . The device of  claim 13 , wherein the filter valve comprises a plurality of filaments that are biased to extend radially outward from the first catheter. 
     
     
         15 . The device of  claim 13 , wherein the filter valve comprises a proximal braided filamentary structure. 
     
     
         16 . The device of  claim 15 , wherein the filter valve comprises a distal non-braided filamentary structure. 
     
     
         17 . The device of  claim 13 , wherein the filter valve comprises a porous polymeric material over a proximal portion of the filter valve. 
     
     
         18 . The device of  claim 16 , wherein the filter valve comprises a porous polymeric material over a distal portion of the filter valve. 
     
     
         19 . The device of  claim 13 , further comprising one or more radiopaque markers provided to the distal end of the first catheter. 
     
     
         20 . The device of  claim 13 , a pressurized infusion source containing a therapeutic agent coupled to the hub, the second catheter adapted to be withdrawn from over the filter valve prior to activation of the infusion source,
 wherein when the infusion source infuses the therapeutic agent through the lumen and out of the orifice of the first catheter, a pressure is generated in the vessel that is suitable to cause the filter valve to automatically move into the open configuration.