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EP-4740880-A2 - SUCTION CATHETER SYSTEMS FOR APPLYING EFFECTIVE ASPIRATION IN REMOTE VESSELS, ESPECIALLY CEREBRAL ARTERIES

EP4740880A2EP 4740880 A2EP4740880 A2EP 4740880A2EP-4740880-A2

Abstract

A suction catheter system is described with a suction extension interfaced with a guide catheter to form a continuous suction lumen extending through a portion of the guide catheter and through the suction extension. The suction extension can be positioned by tracking the suction nozzle through a vessel while moving a proximal portion of the suction extension within the lumen of the guide catheter. The suction extension can comprise a connecting section with a non-circular cross section for interfacing with the inner lumen of an engagement section of the guide catheter. The tubular body of the guide catheter can have a reduced diameter distal section the can be useful to restrain the movement of the suction extension. Proximal fittings attached to the guide catheter can facilitate safe removal of the catheter system from the patient by allowing for the removal of some or all of a tubular extension of the suction extension from the guide catheter behind a hemostatic seal. Pressure sensors connected to the proximal fittings can help to guide the procedures with reduced risk of embolizing thrombus.

Inventors

  • OGLE, MATTHEW, F.

Assignees

  • Route 92 Medical, Inc.

Dates

Publication Date
20260513
Application Date
20180523

Claims (13)

  1. A suction catheter system comprising: a guide catheter comprising: a tubular shaft with a central lumen having a proximal end and a distal opening; and a proximal section operably connected with the proximal end of the tubular shaft and having a fitting configured to connect to a suction device, wherein the tubular shaft comprises an engagement section having an inner diameter associated with the central lumen extending through the engagement section; and a suction extension comprising: a connecting section with a central lumen and a tubular element; a tubular extension comprising a tube that is connected with the tubular element of the connecting section and extends from the connecting section in a distal direction; and a control structure comprising an elongated structure extending from the connecting section in a proximal direction, wherein a bump is formed through a connection of the control structure along a surface of the connection section with extra polymer that provides for a desired shape along with reinforcing the control structure at the connection with the connecting section, the desired shape being a non-circular cross section, the tubular extension having a distal inner diameter that is from about 20 percent to about 90 percent of the inner diameter of the engagement section, wherein the connecting section is configured to slide within the central lumen of the tubular shaft to change a relative position of the connecting section within the central lumen and provide for at least a portion of the suction extension to extend outward from the distal opening of the tubular shaft, wherein a suction lumen is formed extending from the fitting through a portion of the central lumen of the engagement section, the connecting section, and the tubular extension to a distal opening of the tubular extension, and wherein the connecting section engages the central lumen of the engagement section of the guide catheter.
  2. The suction catheter system of claim 1, wherein the bump is due to an embedded control structure.
  3. The suction catheter system of claim 1, wherein the connecting section engages the central lumen of the engagement section of the guide catheter at two locations along a circumference of the connecting section.
  4. The suction catheter system of claim 3, wherein difference in major outer diameter and minor outer diameter is from about 30 microns to about 160 microns.
  5. The suction catheter system of claim 3 or claim 4, wherein major outer diameter of the connecting section separated from the guide catheter is greater than the inner diameter of the engagement section by from about 15 microns to about 150 microns.
  6. The suction catheter system of any one of claims 3-5, wherein an average diameter of the connecting section at its largest circumference (C) specified as C/π is no more than about 76 microns smaller than the inner diameter of the engagement section.
  7. The suction catheter system of any one of claims 1-6, wherein the tubular shaft of the guide catheter comprises a distal section having an inner diameter, the inner diameter of the distal section being from about 0.035 mm to about 0.25 mm less than the inner diameter of the engagement section and the distal section having a length from about 1 mm to about 10 mm.
  8. The suction catheter system of any one of claims 1-7, wherein the guide catheter has an outer diameter ranging from about 6 Fr to about 10 Fr.
  9. The suction catheter system of any one of claims 1-8, wherein a distal most section of the tubular extension has an inner diameter from about 40 percent to about 80 percent of the inner diameter of the engagement section.
  10. The suction catheter system of any one of claims 1-9, wherein the tubular shaft of the guide catheter has a length from about 0.5 m to about 1.8 m and the tubular extension has a length from about 5 cm to about 50 cm.
  11. The suction catheter system of any one of claims 1-10, wherein the tubular extension comprises a plurality of constant diameter segments with a distal segment having a smaller inner diameter than a more proximal segment.
  12. The suction catheter system of any one of claims 1-11, wherein a tip of the suction extension has a curve in an unstrained configuration at a distal end of the suction extension.
  13. The suction catheter system of any one of claims 1-12, wherein an effective seal is formed by a fit between the connecting section and the central lumen of the engagement section of the guide catheter.

Description

FIELD OF THE INVENTION The invention relates to catheters designed for use in bodily vessels with tortuous paths, such as cerebral arteries. In particular, the invention relates to suction catheter systems comprising a guide catheter and a suction extension slidably disposed within the guide catheter. BACKGROUND OF THE INVENTION Procedures in blood vessels of the brain are gaining use as an approach for ameliorating acute stroke events or other interventions in blood vessels in the brain. Blood vessels in the brain follow particularly tortuous paths which can increase the difficulty of reaching target locations in these vessels. Other vessels in a patient can also follow winding paths that increase the difficulty of reaching target locations. Aspiration catheters have found use with respect to removal of clots from vessels. Furthermore, a significant reason for ischemic injury during percutaneous procedures can be generation of emboli that block smaller distal vessels. Aspiration catheters used alone or with embolic protection device can be effective to capture emboli generated during procedures. The delivery of effective devices to the small blood vessels of the brain to remove clots and/or to capture emboli remains challenging. Ischemic strokes can be caused by clots within a cerebral artery. The clots block blood flow, and the blocked blood flow can deprive brain tissue of its blood supply. The clots can be thrombus that forms locally or an embolus that migrated from another location to the place of vessel obstruction. To reduce the effects of the cut off in blood supply to the tissue, time is an important factor. In particular, it is desirable to restore blood flow in as short of a period of time as possible. The cerebral artery system is a highly branched system of blood vessels connected to the interior carotid arteries. The cerebral arteries are also very circuitous. Medical treatment devices should be able to navigate along the circuitous route posed by the cerebral arteries for placement into the cerebral arteries. SUMMARY OF THE INVENTION In a first aspect, the invention pertains to a method for removing thrombus from a patient's vessel using a suction catheter system comprising: proximal fittings comprising a hemostatic valve; a guide catheter with a distal end and a proximal end connected to the proximal fittings; and a suction extension comprising a tubular extension with a distal end and a proximal end, a connecting section at the proximal end of tubular extension, and a control structure extending in a proximal direction from the tubular extension. The method can comprise delivering suction through a suction lumen extending from the distal end of the tubular extension to the proximal end of the guide catheter with the distal end of the tubular extension extending from the distal end of the guide catheter. Generally, for at least a portion of the time of delivery of suction, the connecting section is within the guide catheter, and the control structure extends from the proximal end of the guide catheter. The method can also comprise withdrawing the tubular extension from the guide catheter lumen during delivery of negative pressure in the suction lumen from the proximal fittings, in which the connecting section is withdrawn into the proximal fittings distal to the hemostatic valve such that a suction lumen then extends fully along a lumen of the guide catheter. In a further aspect, the invention pertains to a suction catheter system comprising a guide catheter having a tubular shaft with a central lumen having, a proximal end and a distal opening, a suction extension, and proximal fittings. The suction extension can comprise a connecting section with a central lumen, a tubular extension, and a control structure. The tubular extension can comprise a tube that is connected with the connecting section and extends from the connecting section in a distal direction to form a continuous lumen through the central lumen of the connecting section through the tube of the tubular extension, and the control structure can comprise an elongated structure extending from the connecting section in a proximal direction. The connecting section can be configured to slide within at least a portion of the central lumen of the guide catheter to change the relative position of the connecting section within the central lumen and provide for at least a portion of tubular extension to extend outward from the distal opening of the tubular shaft at appropriate configurations of the connecting section. The proximal fittings generally can be connected to the proximal end of the guide catheter and can comprise a branched manifold with at least one branch having a hemostatic valve and a tubular segment to provide a length between the hemostatic valve and the proximal end of the tubular shaft of the guide catheter that is at least as long as the length of the tube of the suction extension. In another aspect, the invention perta