Method of removing particulate debris with an interventional device

1. A method of removing particulate debris from a vessel using a catheter assembly the method comprising:

inserting and advancing a sheath having a discharge lumen to a location in the vessel said delivery sheath discharge lumen coupled to a collection vessel, said sheath not having an occlusion balloon thereon such that said sheath partially blocks the vessel but allowing some blood flow in the vessel;

inserting and advancing an interventional device to a treatment location said interventional device of type having;

an elongate body enclosing a fluid supply lumen and an angioplasty therapy inflation lumen;

said elongate body having a central axis extending in the direction of the therapy balloon;

a gap communicating with said fluid supply lumen for introducing a primary fluid jet flow in said vessel, said gap located distal of a therapy balloon, said gap projecting said fluid jet in an initial direction away from the central axis of the interventional device; a tapered wall located immediately adjacent said gap, and forming an annular surface next to the gap on the interventional device;

said wall serving to restrict entrainment of fluid by said primary fluid flow, thereby creating a pressure difference across said primary fluid jet flow such that said primary fluid flow turns through an angle away from said initial direction away from said wall and turns toward said wall thereby exhibiting the Coanda effect;

delivering angioplasty treatment located near the distal tip of said elongate body;

injecting a primary fluid; and

promoting retrograde flow into said discharge lumen.

2. The method of claim 1 wherein said primary fluid is supplied by a supply syringe chamber.

3. The method of claim 2 wherein the fluid supplied is a thrombolytic.

4. The method of claim 2 wherein the fluid supplied is saline.

5. The method of claim 2 wherein the fluid supplied is contrast agent.

6. The method of claim 1 wherein said injection is carried out while moving said interventional device in said vessel with respect to said delivery sheath.

7. The method of claim 6 wherein said moving step begins near said occlusion and ends after the interventional device enters the delivery sheath.

8. The method of claim 1 wherein said fluid is injected at a first injection pressure above the blood pressure in the vessel and the injected fluid pressure drop to a second exhaust pressure in said delivery catheter where said exhaust pressure is above said blood pressure, establishing a pressure gradient in said discharge lumen and promoting flow from said gap to said discharge lumen.

9. The method of claim 1 wherein said discharge lumen is coupled to a syringe collection chamber.

10. The method of claim 1 wherein said discharge lumen is coupled to a syringe vacuum chamber.

11. The method of claim 1 wherein said primary fluid is supplied by a supply syringe chamber and said discharge lumen is coupled to a syringe vacuum chamber, and said supply syringe and vacuum syringe are operated together to couple fluid supply with discharge lumen collection.

12. A method of removing particulate debris from a vessel using a catheter assembly the method comprising:

inserting and advancing a sheath having a discharge lumen to a location in the vessel said delivery sheath discharge lumen coupled to a collection vessel; said sheath not having an occlusion balloon thereon such that said sheath partially blocks the vessel but allowing some blood flow in the vessel;

inserting and advancing an interventional device to a treatment location said interventional device of type having;

an elongate body enclosing a fluid supply lumen and a stent delivery inflation lumen;

a gap communicating with said fluid supply lumen for introducing a primary fluid flow in said vessel, said gap located distal of a stent deployment balloon, said gap projecting fluid in an initial direction away from the central axis of the interventional device; a tapered wall located immediately adjacent said gap; and forming an annular surface next to the gap on the interventional device;

said wall serving to restrict entrainment of fluid by said primary fluid flow, thereby creating a pressure difference across said primary fluid flow such that said primary fluid flow turns through an angle away from said initial direction of the toward said wall thereby exhibiting the Coanda effect;

delivering stent treatment located near the distal tip of said elongate body;

injecting a primary fluid; and

promoting retrograde flow into said discharge lumen.

13. The method of claim 12 further including a suction applied to said sheath lumen to withdraw material from said vessel.

14. The method of claim 13 further including a suction applied to said sheath lumen to withdraw material from said vessel.