Search

EP-4510973-B1 - MAGNETIC RELEASE MECHANISM

EP4510973B1EP 4510973 B1EP4510973 B1EP 4510973B1EP-4510973-B1

Inventors

  • VALDEZ, MICHAEL G.

Dates

Publication Date
20260506
Application Date
20230602

Claims (15)

  1. A catheter (10) for delivering an implant (14) to a patient, the catheter comprising: a shaft (28) defining a lumen (30) extending from a proximal end (10A) to a distal end (10B) of the shaft, the shaft comprising: a spacer wall (38) enclosing the lumen within a distal region (10C) of the shaft, wherein the distal region extends from the distal end towards the proximal end a distance equal to five diameters of the shaft; and a magnetic release mechanism (12) comprising: a magnet (36) disposed within the lumen, wherein the magnet is disposed within the distal region of the lumen between the spacer wall and the proximal end.
  2. The catheter of claim 1, further comprising: a marker strip (42) circumscribing an exterior of the lumen and aligning with the spacer wall.
  3. The catheter of claim 1 or claim 2, wherein the spacer wall is spaced from the distal end to form a socket (40) open to the distal end of the shaft.
  4. The catheter of claim 3, further comprising: an implant (14) at least partially received within the socket.
  5. The catheter of claim 4, wherein the implant includes a helical anchor wire (48) extending from an outward surface of the implant opposite an inward surface of the implant abutting the spacer wall.
  6. The catheter of claim 4, wherein the implant is rotationally restrained within the socket by a magnetic field of the magnet.
  7. The catheter of claim 6, wherein a magnetic axis of the magnet is perpendicular to a centerline (44) of the shaft, and wherein a maximum magnetic torque imposed on the implant imposes no more than a threshold force onto the implant, the threshold force between 5 newtons and 30 newtons.
  8. The catheter of any preceding claim, wherein the magnetic release mechanism further comprises: an inner shaft (34) joined to the magnet and extending within the lumen from the magnet to the proximal end, wherein the magnet is a permanent magnet.
  9. The catheter of claim 8, further comprising: a handle (16); and a bushing (72) affixed to the handle and the shaft at the proximal end, wherein the handle restrains linear displacement of the bushing and the shaft with respect to the handle, and wherein the shaft is rotatable with respect to the handle about a centerline of the handle.
  10. The catheter of claim 9, further comprising: a knob (20) joined to the handle; and a terminal member (24) affixed to the inner shaft and coinciding with the handle, wherein external threads (74A) of the terminal member engage internal threads (74B) of the knob such that rotation of the knob displaces the magnet within the lumen with respect to the spacer wall.
  11. The catheter of claim 10, further comprising: an end cap (18) joined to the handle opposite the knob; and a spring (22) compressed within the handle between the end cap and the terminal member.
  12. The catheter of any preceding claim, further comprising: a sheath (32) encircling the shaft and extending from the proximal end to a terminal end (32A) spaced from the distal end of the shaft, wherein the shaft protrudes from the sheath at the distal end.
  13. The catheter of claim 12, when claim 12 is dependent upon any one of claims 1-6, further comprising: a handle (16) affixed to the shaft at the proximal end, wherein the handle restrains linear and rotational displacement of the shaft with respect to the handle.
  14. The catheter of claim 13, wherein the magnet is an electromagnet, the electromagnet comprising: a core (120); a winding (122) encircling the core; and leads (102) extending from the windings to the handle electrically connecting the electromagnet to a switch mounted to the handle, optionally wherein the magnetic release mechanism further comprises: a power supply (94) electrically connected to the switch, wherein the switch includes an open state that electrically disconnects the power supply from the electromagnet and a closed state that electrically connects the power supply to the electromagnet.
  15. The catheter of any preceding claim, wherein the catheter is sterilized.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) This application claims the benefit of U.S. Provisional Application No. 63/349,475, filed June 6, 2022, and entitled "MAGNETIC RELEASE MECHANISM." . BACKGROUND The patent disclosure relates generally to mechanisms for delivering an implant to a patient, and more specifically to an implant delivery system utilizing a catheter with a magnetic release mechanism. Minimally invasive surgical techniques are improving patient outcomes and recovery times. Catheters can be used to attach sensors and mechanical couplings among other possible medical device implants within a patient during some minimally invasive procedures. Prior attempts to deliver implants includes catheters equipped with a mechanical coupler (e.g., grips, clamps, and other holding attachments and adapters). Each mechanical coupler incorporates complex mechanisms which require larger catheter sizes to facilitate integration of the mechanical coupler into the catheter. Furthermore, mechanical coupling mechanisms can over restrain the implant, particularly in a torsional direction, which can lead to inadvertent tissue damage when force or moments applied by the catheter exceed tissue strength. EP 2 749 309 describes an endoluminal prosthesis (10) for placing in a body passage of a patient, including a ureteral stent (12), the ureteral stent comprising a generally tubular housing (14) having a proximal end (16) and a distal end (18) and a lumen (20) longitudinally disposed therethrough, with cation-exchange resin beads (22) disposed within the tubular housing, and at least one anchoring mechanism (24) disposed on a distal end of the tubular housing, where at least one retention screen (26) is disposed within the lumen of the ureteral stent configured to retain the plurality of beads. US 2015/112377 describes a collapsible blood filtering aortic arch bridge comprising a dumbbell shaped chassis having a tubular waist, a first conical end, and a second conical end such that only a periphery of the first and second ends contact the intima of an aortic arch when the bridge is disposed and expanded within the aortic arch of a patient. The waist is flexible so that the bridge can bend to comply with the curvature of the aortic arch. The bridge additionally comprises a blood filtering sleeve disposed over an interior or an exterior of the chassis for filtering blood flowing through the bridge into aortic arch vessels of the patient when the bridge is disposed within the aortic arch. Furthermore, the bridge comprises a retrieval sleeve disposed over the exterior of the chassis for collapsing the bridge to a cylindrical form for retrieval of the bridge from the aortic arch. SUMMARY A catheter includes a magnetic release mechanism comprising a magnet. The catheter includes a shaft that defines a lumen. The shaft extends from a proximal end to a distal end. A spacer wall within a distal region of the shaft encloses the lumen, and the magnet abuts the spacer wall between the spacer wall and the proximal end of the catheter. A catheterization procedure, not forming part of the presently claimed invention, includes guiding the catheter to an attachment point and rotating a handle of the catheter to thereby rotate the magnet. Rotation of the magnet induces rotation of an implant retained at the distal end of the catheter by the magnet. Disengaging the magnetic release mechanism decouples the implant from the catheter. The invention is directed to a catheter as defined in independent claim 1. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a schematic view of a catheter with a first exemplary magnetic release mechanism.FIG. 1B is a schematic side view illustrating exemplary features of an implant.FIG. 1C is an end view illustrating exemplary features of the implant.FIG. 1D and FIG. 1E are schematic views of the proximal and distal ends of the catheter depicted in FIG. 1A.FIG. 1F is a schematic view of the catheter in which the magnetic release mechanism is disengaged.FIG. 2A is a schematic view of a catheter equipped with a second exemplary magnetic release mechanism.FIG. 2B and FIG. 2C are schematic views of the proximal and distal ends of the catheter depicted in FIG. 2A.FIG. 3A, FIG. 3B, and FIG. 3C are schematic views of a patient's heart depicting attachment of an implant utilizing a catheter equipped with a magnetic release mechanism.FIG. 4 is a flow chart describing a procedure for attaching an implant to a patient. DETAILED DESCRIPTION As described herein, a catheter includes a magnetic release mechanism housed within a distal region of a lumen. Catheters equipped with the magnetic release mechanism can be used to deliver and/or manipulate an implant to an attachment site within the patient to perform minimally invasive procedures. The magnetic release mechanism in accordance with this disclosure is less complex relative to prior mechanical release mechanisms, which in turn reduces the minimum possible catheter size. Addi