Shape-set textile structure based mechanical thrombectomy methods
A biomedical shape-set textile structure based mechanical thrombectomy systems and methods are described. In one of the embodiments, the mechanical thrombectomy device can be customized to the length of the clot in each patient. In one of the embodiments, the mechanical thrombectomy device because of the textile structure has a very low overall profile or thickness that is less than 0.0125 inches (0.317 mm) and therefore can be deployed within microcatheters with inner lumen diameter as small as 0.014 inches (0.355 mm).
1. A method of treating a thrombus in a vessel with self-expanding bulbs, the method comprising:
advancing a guidewire in the vessel proximal to the thrombus;
advancing a guide catheter in the vessel and over the guidewire;
after advancing the guide catheter, removing the guidewire from the vessel;
advancing a microwire in the vessel and through the guide catheter, wherein advancing the microwire includes crossing the thrombus by 0.5 mm to 5 mm;
advancing a microcatheter in the vessel and over the microwire, wherein advancing the microcatheter includes crossing the thrombus with a distal end of the microcatheter;
after advancing the microcatheter, removing the microwire from the vessel;
after removing the microwire, inserting a thrombectomy device from an introducer sheath into the microcatheter, the thrombectomy device including:
an elongate support structure including a plurality of wires woven to form a textile fabric, the elongate support structure comprising
five to twenty said self-expanding bulbs,
a plurality of necks longitudinally between and radially inward of the self-expanding bulbs, and
a distal neck radially inward of a distal-most bulb of the self-expanding bulbs; and
a delivery system coupled to the elongate support structure, the delivery system including a hypotube including a plurality of longitudinally-spaced kerfs including a plurality of interspersed cut patterns, wherein a pitch of the plurality of longitudinally-spaced kerfs varies longitudinally along the hypotube, and wherein each of the plurality of longitudinally-spaced kerfs includes rounded edges;
after inserting the thrombectomy device from the introducer sheath into the microcatheter, advancing the thrombectomy device in the vessel and through the microcatheter proximate to the distal end of the microcatheter, wherein advancing the thrombectomy device includes crossing the thrombus;
after advancing the thrombectomy device, maintaining a location of the delivery system of the thrombectomy device while retracting the microcatheter, wherein upon being unsheathed from the microcatheter at least some of the self-expanding bulbs of the elongate support structure of the thrombectomy device self-expand from a radially compressed state to a radially expanded state, wherein retracting the microcatheter is at least until the distal end of the microcatheter is proximal to the thrombus; and
retracting the microcatheter and the delivery system of the thrombectomy device into the guide catheter, wherein during retraction of the microcatheter and the delivery system of the thrombectomy device, the at least some of the self-expanding bulbs of the elongate support structure of the thrombectomy device in the radially expanded state remain in the radially expanded state and others of the self-expanding bulbs of the elongate support structure of the thrombectomy device in the radially compressed state remain in the radially compressed state.
2. The method of claim 1 , further comprising, before retracting the microcatheter and the delivery system of the thrombectomy device into the guide catheter, torsionally rasping the thrombectomy device including removing portions of the thrombus attached to an endothelium wall, entrapping the thrombus in the radially expanded elongate support structure of the thrombectomy device, and collecting emboli in the radially expanded elongate support structure.
3. The method of claim 1 , wherein retracting the microcatheter and the delivery system is at a similar rate and while applying negative pressure to the vessel.
4. The method of claim 1 , wherein the vessel comprises a blood vessel in a brain or a blood vessel in a leg.
5. The method of claim 1 , further comprising:
torsionally rasping the thrombectomy device including entrapping the thrombus in the portion of the elongate support structure.
6. The method of claim 5 , wherein torsionally rasping the thrombectomy device includes removing portions of the thrombus attached to an endothelium wall.
7. The method of claim 5 , wherein torsionally rasping the thrombectomy device includes collecting one or more emboli released from the thrombus in the portion of the elongate support structure.
8. The method of claim 5 , wherein, during torsionally rasping the thrombectomy device, a ratio of rotation of the delivery system of the thrombectomy device to rotation of the elongate support structure of the thrombectomy device is not 1:1.
9. The method of claim 5 , wherein torsionally rasping the thrombectomy device comprises rotating the delivery system of the thrombectomy device at least 360 degrees, resulting in a rotation of the elongate support structure of the thrombectomy device of less than 360 degrees.
10. The method of claim 1 , wherein the elongate support structure comprises at least two of the five to twenty bulbs having different outer diameters in the radially expanded state.
11. The method of claim 1 , wherein the elongate support structure is tapered.
12. The method of claim 1 , wherein the thrombectomy device in the radially compressed state has a thickness less than 0.0125 inches.
13. The method of claim 1 , wherein expanding the portion of the elongate support structure from the radially compressed state to the radially expanded state comprises expanding the vessel by 0% to 30%.