Intravascular treatment of vascular occlusion and associated devices, systems, and methods
Systems and methods for removal of thrombus from a blood vessel in a body of a patient are disclosed herein. The method can include: providing a thrombus extraction device including a proximal self-expanding member formed of a unitary fenestrated structure, a distal substantially cylindrical portion formed of a net-like filament mesh structure, and an inner shaft member connected to a distal end of the net-like filament mesh structure; advancing a catheter constraining the thrombus extraction device through a vascular thrombus, deploying the thrombus extraction; retracting the thrombus extraction device to separate a portion of the thrombus from the vessel wall and to capture the portion of the thrombus within the net-like filament mesh structure; and withdrawing the thrombus extraction device from the body to remove thrombus from the patient.
1. A thrombectomy system for removal of a vascular thrombus from a blood vessel of a patient, the thrombectomy system comprising:
a thrombus extraction device including—
a proximal self-expanding coring element; and
a distal expandable cylindrical portion formed of a braided filament mesh structure having a proximal end attached to a distal end of the coring element; and
a catheter comprising a lumen configured to constrain the thrombus extraction device, an intermediate shaft coupled to a proximal end of the self-expanding coring element, and an inner shaft coupled to a distal end of the expandable cylindrical portion and slidably displaceable with respect to the intermediate shaft to control expansion of the expandable cylindrical portion; and
an introducer sheath including—
an elongate sheath defining an insertion lumen;
a self-expanding funnel affixed to a distal end of the elongate sheath; and
an elongate obturator including a sheath capture feature configured to retain the self-expanding funnel in a constrained configuration.
2. The thrombectomy system of claim 1 wherein the proximal self-expanding coring element is formed of a unitary fenestrated structure and is configured to core and separate a portion of the vascular thrombus from the blood vessel, and wherein the distal expandable cylindrical portion is configured to capture the vascular thrombus portion.
3. The thrombectomy system of claim 1 wherein the coring element comprises a stent.
4. The thrombectomy system of claim 3 , wherein the stent includes a ring feature slidably coupled to the inner shaft and the inner shaft includes a stop feature fixed to the inner shaft, wherein the stop feature is configured to engage with the ring feature when the mesh structure and the stent are in full expansion.
5. The thrombectomy system of claim 4 , further comprising a locking mechanism configured to secure the inner shaft relative to the intermediate shaft when the mesh structure and the stent are in full expansion.
6. The thrombus extraction device of claim 5 , wherein the locking mechanism is configured to maintain a desired radial force on a vessel wall when the stent is compressed.
7. The thrombus extraction device of claim 5 , wherein the locking mechanism moveably secures the inner shaft relative to the intermediate shaft via a spring.
8. The thrombectomy system of claim 1 , wherein the proximal end of the coring element is coupled to the distal end of the intermediate shaft via a plurality of struts extending at a coring angle relative to a longitudinal axis of the thrombus extraction device.
9. The thrombectomy system of claim 1 wherein the obturator includes an elongate shaft having a distal end, wherein the sheath capture feature is located proximate to the distal end of the elongate shaft of the obturator, and wherein the obturator is configured to be received within the insertion lumen of the elongate sheath.
10. The thrombectomy system of claim 1 wherein the introducer sheath further includes a sealed hub located at a proximal end of the elongate sheath.
11. The thrombectomy system of claim 10 , wherein the sealed hub comprises an aspiration port.
12. The thrombectomy system of claim 1 wherein the self-expanding funnel has a diameter equal to or less than a diameter of the elongate sheath when the self-expanding funnel is in the constrained configuration.
13. The thrombectomy system of claim 1 wherein the obturator includes an atraumatic tip located at the distal end of the obturator, and wherein the atraumatic tip is radiopaque.
14. The thrombectomy system of claim 1 wherein the self-expanding funnel is permeable to blood.
15. The thrombectomy system of claim 1 wherein the self-expanding funnel has a conical shape and is formed from at least one of a castellated nitinol braid, a nitinol braided stent, a laser cut nitinol, a laser cut polymer tube, an injection molded polymeric structure, or an inflatable balloon.
16. The thrombectomy system of claim 1 , wherein the obturator is configured to be received within the insertion lumen of the elongate sheath and comprises a connection fitting configured to sealingly connect with a distal end of the elongate sheath.
17. The thrombectomy system of claim 1 , wherein the self-expanding funnel has a length that is at least equal to a length of the self-expanding coring element.
18. The thrombectomy system of claim 1 , wherein the introducer sheath comprises a self-sealing aperture located at a proximal end of the introducer sheath.
19. The thrombectomy system of claim 18 , further comprising an aperture dilator sized to be receivable within the self-sealing aperture and having an internal diameter larger than a diameter of the self-sealing aperture in a sealed configuration.
20. The thrombectomy system of claim 1 , wherein the introducer sheath comprises an aspiration port located at a proximal end of the inserter elongate sheath, wherein the aspiration port is selectably fluidly connected to the insertion lumen via an aspiration valve.
21. The thrombectomy system of claim 1 , wherein the insertion lumen is sized to slidably receive the catheter of the thrombus extraction device.
22. The thrombectomy system of claim 1 , wherein the expandable cylindrical portion is formed on the self-expanding coring element to form a unitary thrombus extraction device.