Closed tip dynamic microvalve protection device
An endovascular microvalve device for use in a vessel during a therapy procedure includes an outer catheter, an inner catheter displaceable within the outer catheter, and a filter valve coupled to the distal ends of the inner and outer catheters. The valve is constructed of a braid of elongate first filaments coupled together at their proximal ends in a manner that the first filaments are movable relative to each other along their lengths. A filter is provided to the braid formed by electrostatically depositing or spinning polymeric second filaments onto the braided first filaments. 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.
1. An endovascular microvalve device for temporary use in a vessel having a vessel wall which defines a diameter during an intravascular procedure, comprising:
a) a flexible outer catheter having a proximal end and a distal end;
b) a flexible inner catheter having a proximal end and a distal end with an orifice, the inner catheter extending through and longitudinally displaceable relative to the outer catheter; and
c) a filter valve having a proximal end and distal end, the proximal end of the filter valve coupled to the distal end of the outer catheter, and the distal end of the filter valve coupled to the inner catheter adjacent the distal end of the inner catheter, such that longitudinal displacement of the inner catheter relative to the outer catheter moves the filter valve from a non-deployed configuration to a deployed configuration, the filter valve having a proximal portion comprising a braided filamentary structure and distal portion comprising a non-braided spirally wound filamentary structure, and the distal portion further comprising a porous polymeric material coupled to the non-braided spirally wound filamentary structure, the porous polymeric material defining a pore size not exceeding 500 μm, wherein:
once the filter valve is in the deployed configuration in the vessel, the filter valve is dynamically movable depending on a local fluid pressure 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 configuration with a first diameter smaller than the diameter of the vessel such that fluid flow about the filter valve is permitted, and
when the fluid pressure is higher on a distal side of the filter valve, the filter valve assumes a configuration with a second diameter relatively larger than the first diameter and in which the filter valve is adapted to contact the vessel wall.
2. The endovascular microvalve device according to claim 1 , wherein:
the proximal portion exerts a higher radial force than the distal portion of the filter valve.
3. The endovascular microvalve device according to claim 1 , wherein:
the filter valve defines a maximum diameter at an intersection of the proximal and distal portions.
4. The endovascular microvalve device according to claim 1 , wherein:
the braided filamentary structure of the proximal portion comprises a first number of filaments, and the non-braided spirally wound filaments of the distal portion comprises a second number of filaments, and the first number is greater than the second number.
5. The endovascular microvalve device according to claim 1 , wherein:
the spirally wound filamentary structure consists essentially of filaments extending in a common rotational direction.
6. The endovascular microvalve device according to claim 1 , wherein:
the spirally wound filamentary structure includes filaments extending in both clockwise and counter-clockwise rotational directions.
7. The endovascular microvalve device according to claim 1 , wherein:
the spirally wound filamentary structure consists essentially of filaments that are equally displaced about a circumference of the filter valve.
8. The endovascular microvalve device according to claim 1 , wherein:
the spirally wound filamentary structure includes spiral wound filaments that are unequally displaced about a circumference of the filter valve.
9. The endovascular microvalve device according to claim 1 , wherein:
the braided filamentary structure in the proximal portion and spirally wound filamentary structure of the distal portion are comprised of filaments having a diameter of 0.025 mm to 0.127 mm.
10. The endovascular microvalve device according to claim 9 , wherein:
the filaments of the proximal portion have proximal ends secured relative to each other on the outer catheter such that the filaments of the proximal portion define a round configuration extending between their secured proximal ends on the outer catheter and the distal portion of the filter valve.
11. The endovascular microvalve device according to claim 1 , wherein:
the spirally wound filamentary structure includes spirally wound filaments, and the filaments extends in a first winding direction when the filter valve is in the non-deployed configuration, and when the filter valve is moved from the non-deployed configuration to the deployed configuration, the filaments reverse winding direction relative to the first winding direction.
12. The endovascular microvalve device according to claim 1 , wherein:
the proximal portion further includes a porous polymeric material provided to the braided filamentary structure.
13. The endovascular microvalve device according to claim 1 , wherein:
the filter valve in the deployed configuration forms a substantially oblong spherical or frustoconical shape.
14. The endovascular microvalve device according to claim 1 , wherein:
in the non-deployed configuration, the filter valve includes a distal face that is convex in shape, and in the deployed configuration, the distal face of the filter valve is planar or concave.
15. An endovascular microvalve device for temporary use in a vessel having a vessel wall which defines a diameter during an intravascular procedure, comprising:
a) a flexible outer catheter having a proximal end and a distal end;
b) a flexible inner catheter having a proximal end and a distal end with an orifice, the inner catheter extending through and longitudinally displaceable relative to the outer catheter; and
c) a filter valve having a proximal end and distal end, the proximal end of the filter valve coupled to the distal end of the outer catheter, and the distal end of the filter valve coupled to the inner catheter adjacent the distal end of the inner catheter, such that longitudinal displacement of the inner catheter relative to the outer catheter moves the filter valve from a non-deployed configuration to a deployed configuration, the filter valve having a proximal portion comprising a braided filamentary structure consisting of a first number of filamentary portions, and a distal portion comprising an arrangement of second number of filamentary portions, the second number fewer than the first number, and the distal portion further comprising a porous polymeric material coupled to the filamentary portions of the distal portion, the porous polymeric material defining a pore size not exceeding 500 μm, wherein:
once the filter valve is in the deployed configuration in the vessel, the filter valve is dynamically movable depending on a local fluid pressure 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 configuration with a first diameter smaller than the diameter of the vessel such that fluid flow about the filter valve is permitted, and
when the fluid pressure is higher on a distal side of the filter valve, the filter valve assumes a configuration with a second diameter relatively larger than the first diameter and in which the filter valve is adapted to contact the vessel wall.
16. The endovascular microvalve device according to claim 15 , wherein:
the proximal portion exerts a higher radial force than the distal portion of the filter valve.
17. The endovascular microvalve device according to claim 15 , wherein:
the second number of filamentary portions coextend from the first number of filamentary portions.
18. The endovascular microvalve device according to claim 15 , wherein:
the first and second number of filamentary portions are discrete from each other.
19. The endovascular microvalve device according to claim 15 , wherein:
the second number of filamentary portions are equally displaced about a circumference of the filter valve.
20. The endovascular microvalve device according to claim 15 , wherein:
the second number of filamentary portions are unequally displaced about a circumference of the filter valve.
21. The endovascular microvalve device according to claim 15 , wherein:
the second number of filamentary portions are spirally wound about the distal portion.
22. The endovascular microvalve device according to claim 21 , wherein:
the second number of filamentary portions extends in a first winding direction when the filter valve is in the non-deployed configuration, and when the filter valve is moved from the non-deployed configuration to the deployed configuration, the second number of filamentary portions reverse winding direction relative to the first winding direction.
23. The endovascular microvalve device according to claim 15 , wherein:
the first and second number of filamentary portions have a diameter of 0.025 mm to 0.127 mm.
24. The endovascular microvalve device according to claim 23 , wherein:
the first number of filamentary portions of the proximal portion have proximal ends secured relative to each other on the outer catheter such that the first number of filamentary portions define a round configuration extending between their secured proximal ends on the outer catheter and the distal portion of the filter valve.
25. The endovascular microvalve device according to claim 15 , wherein:
the filter valve defines a maximum diameter at an intersection of the proximal and distal portions.
26. The endovascular microvalve device according to claim 15 , wherein:
the proximal portion further includes a porous polymeric material provided to the braided filamentary structure.
27. The endovascular microvalve device according to claim 15 , wherein:
in the non-deployed configuration, the filter valve includes a distal face that is convex in shape, and in the deployed configuration, the distal face of the filter valve is planar or concave.