Methods and devices for evaluating and treating diseased vessels

Abstract

A device for treating thrombus or spasm or other diseased vessels in a patient may include an elongate shaft having a lumen. An electro-drug unit may be coupled with a proximal end of the elongate shaft and configured to facilitate evaluation and treatment of thrombus or spasm or other disease in the vessel. An expandable cage may be coupled with a distal end of the elongate shaft. The cage may have a contracted configuration for delivery through the vessel to the thrombus, spasm, or diseased region of the vessel, and an expanded configuration for wrapping the thrombus or supporting the spasm or diseased vessel. An electrical element may be coupled with the expandable cage and may be configured to sense characteristics of a thrombus or diseased vessel, or may be configured to provide treatment for a thrombus, spasm, or diseased vessel.

Description

[0001] Priority claim

[0002] This patent application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 334,295 (Attorney Docket No. 5543.003PRV), filed on April 25, 2022; the entire contents of which are incorporated herein by reference.

[0003] Cross-references to related patent documents

[0004] This patent application is also related to US Patent Application No. 17 / 336,791, now US Patent No. 11,291,463; the entire contents of which are incorporated herein by reference. Background Art

[0005] Vascular obstruction is usually caused by a clot (also referred to herein as a thrombus), and this may be referred to as a thromboembolic event, and may result in conditions such as stroke, pulmonary embolism, peripheral thrombosis, etc. Thromboembolic events affect many people each year and may result in morbidity in patients worldwide. Some examples of morbidity include ischemia, limb loss, angina, myocardial infarction, stroke, and pulmonary embolism. In some cases, death may result as a result of a thromboembolic event.

[0006] Common existing techniques for treating thromboembolic events include embolectomy, surgery, use of therapeutic agents such as streptokinase or urokinase or other thrombolytic agents, or thrombectomy devices.

[0007] Other diseases or conditions can also lead to vascular obstruction. For example, a blood vessel can spasm, resulting in a blockage that can limit blood flow in the vessel. In the case of the middle cerebral artery, irritation such as trauma, blood, drugs, or seizures can cause spasm. Spasm can lead to functional narrowing of the artery and the resulting reduction in blood flow can lead to a stroke.

[0008] Current treatments for blockages caused by clots or spasms, or blockages due to other causes, attempt to restore blood flow and can present challenges depending on the circumstances. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In the accompanying drawings, which are not necessarily drawn to scale, the same numerals may describe similar components in different views. The same numerals with different letter suffixes may represent different instances of similar components. The accompanying drawings generally illustrate various embodiments discussed in this document by way of example and not limitation.

[0010] Figure 1 An example of a stent retriever system that can be used to evaluate and treat thrombus is shown.

[0011] Figure 2 shows that it may be included in Figure 1An example of an electro-drug unit in a stent retriever system.

[0012] Figures 3A to 3B shows that it may be included in Figure 1 An example of an elongated shaft in a stent retriever system.

[0013] Figure 4 shows that it may be included in Figure 1 An example of a distal portion of a stent retriever in a stent retriever system.

[0014] Figures 5A to 5K Examples of methods of evaluating and treating thrombus are shown.

[0015] Figures 6A to 6D Examples of methods of evaluating and treating vasospasm are shown. DETAILED DESCRIPTION

[0016] Blockage of a blood vessel is usually caused by a clot, and this may be referred to as a thromboembolic event, and may result in conditions such as stroke, pulmonary embolism, peripheral thrombosis, etc. Thromboembolic events affect many people each year and may result in morbidity in patients worldwide. Some examples of morbidity include ischemia, limb loss, angina, myocardial infarction, stroke, pulmonary embolism. In some cases, death may result as a result of a thromboembolic event.

[0017] Common existing technologies for treating thromboembolic events include embolectomy, surgery, use of therapeutic agents such as streptokinase or urokinase or other thrombolytic agents, or thrombectomy devices. These devices can provide different clinical outcomes depending on the blockage being treated. In some cases, it can be beneficial to more accurately assess the type of blockage in order to provide patients with better, more customized treatments, and in some cases, it can be beneficial to provide a treatment device that can provide patients with different treatments or combinations of treatments based on the type of blockage, thereby improving the safety of the procedure, reducing costs associated with having to use additional equipment, reducing operating time, reducing inventory, etc. In some cases, diagnostic or evaluation features can be combined with treatment features in a single device.

[0018] In the case where the obstruction is a thrombus (also referred to herein as a clot), the thrombus can be a red thrombus or a white thrombus. A red thrombus is a clot rich in red blood cells, which contain a higher concentration of hemoglobin, which is rich in iron, while a white thrombus is a clot rich in white blood cells, proteins, and fibrous tissue. If the type of clot is known, it can be more effective to treat and remove the thrombus from the blood vessel, so that the treatment can be customized for the specific type of clot, which will be discussed in more detail below.

[0019] Figure 1A schematic diagram of a device 100 and system 130 is shown that can be used to evaluate and provide customized treatment for removing a clot from a patient 132. The device 100 can be referred to as a stent retriever. The devices, systems, and methods disclosed herein are primarily directed to the evaluation and treatment of blood clots in cerebral arteries, but this is not intended to be limiting and the clot can be in any vessel of the body, and the methods, systems, and devices disclosed herein can be used to treat clots anywhere.

[0020] A system 130 for evaluating and treating a thrombus in a vessel may include an electrodrug catheter 102 including an elongated shaft 116 having a proximal end and a distal end. The distal end may be disposed within the patient's body and include an expandable member 108 for removing a clot, while the proximal end may remain outside the patient's body and include a handle 134 for controlling or manipulating the device. An inner lumen may extend between the proximal and distal ends of the elongated shaft 116. An electro-drug unit 136 may be coupled to the proximal end of the elongated shaft and may be integral with or coupled to or disposed in the handle 134. An expandable member, such as an expandable cage 108, may be coupled to the distal end of the elongated shaft 116 having a coupling element 112 (e.g., those disclosed in U.S. Patent Application No. 17 / 336,791, now U.S. Patent No. 11,291,463, previously incorporated herein by reference). An example of the coupling element 112 may be a ring-like member that is crimped, welded, bonded, or otherwise coupled to the expandable cage 108 and the elongated shaft 116 .

[0021] The elongated shaft 116 may be formed from a polymer or metal tube and have one or more lumens. Additional details regarding the elongated shaft 116 are disclosed in FIG. 3 below.

[0022] The electro-drug unit 136 may be fixedly or releasably coupled to the proximal end of the elongated shaft. Additional details regarding the electro-drug unit are provided below. Figure 2 discussed in.

[0023] The expandable cage 108 has a collapsed configuration suitable for delivery to a thrombus through a vessel, and also has an expanded configuration in which the cage will radially expand into the thrombus and entangle it, thereby capturing the thrombus in the cage, so that when the expandable cage is retracted proximally, the thrombus can be removed from the vessel to restore or improve the patency of the vessel. The expandable cage can be balloon expandable or self-expandable, or can be expandable based on a temporary change in its electrical properties. In the case where the cage is self-expanding, the outer sheath 102 or outer catheter can have a distal portion 110 that is slidably disposed on the shaft 116 and the cage 108 to provide a constraint to prevent self-expansion. When the cage is advanced distally of the constraint (or when the constraint is retracted proximally relative to the cage), the cage becomes unconstrained and can self-expand to engage the thrombus. In the example where the cage is balloon expandable, the cage can be disposed on an expandable balloon (not shown) that expands the cage radially when expanded. In the case of a balloon expandable cage, the outer sheath 102 is optional and, if used, provides protection for the expandable cage. In any instance, the proximal or distal movement of the expandable sheath 102 can be controlled by an actuator, such as a lever, a slider, a wheel, etc., on the handle 134 (not shown) and known in the art. The proximal portion of the expandable cage 108 may include an inclined open proximal end 118, and the distal end of the cage may include a closed tapered conical distal end 106 that converges to a point 114 to help contain and capture any retrieved thrombus. In addition, the distal end of the cage may include an inner lumen 104 that allows a guidewire to be slidably disposed through the cage and the shaft 116 to facilitate delivery to the target treatment area over the guidewire. The expandable cage can have any number of geometric shapes, but in this example, the cage is formed by a series of interconnected closed cells. Some examples of cell geometries that may be used are disclosed in US Patent Application No. 17 / 336,791 (now US Patent No. 11,291,463); previously incorporated herein by reference.

[0024] The system 130 for evaluating and treating thrombi may also include an imaging system 140, such as a computerized tomography system (CT), a magnetic resonance imaging system (MRI), or any other imaging system known in the art, which is used to image thrombi in a patient's vessels (e.g., vessels in the brain). The imaging system 140 provides an image of the thrombus to a processor 142 so that the processor can characterize the thrombus and help evaluate the thrombus, such as the size, location, type, morphology, etc. of the thrombus. The processor can then provide this information to a physician to help the physician determine an appropriate treatment plan. In some cases, the processor can provide a suggested treatment plan to the physician based on the evaluation of the imaging data. Once the processor or the physician or both have reviewed the imaging data and characterization of the thrombus, the physician can begin treating the thrombus, or the processor can issue instructions to the electro-drug unit 136 and help control the treatment. When the catheter 100 is used to treat a patient, sensors on the catheter can provide feedback to the processor 142, and the processor can make adjustments to the treatment in real time as the patient is treated, which will be discussed further below. The various treatment options are discussed in more detail below.

[0025] Figure 2 A method for use with a catheter (e.g. Figure 1 2 and 3. Further details of the electro-drug unit 200 on the proximal end of the catheter (shown in FIG. 1 ). Here, the housing or handle 202 is sized and shaped to be easily grasped and manipulated by the operator's hand. The handle may house all of the circuitry or other components, or some may be housed in the housing and other circuits or components may be external to the housing, such as coupled to the housing, or separate and detachable from the housing, but operably coupled to the circuits and components in or on the housing, such as via a wireless connection (such as a near field communication or Bluetooth connection), operably coupled to a cable, or other techniques known in the art. For example, a battery 204 (rechargeable or disposable) may be disposed in the handle and may be used to power the device or provide current as part of evaluation and treatment, as will be described below. In other examples, power for the catheter may be provided by an external power source (such as an external battery), or the catheter may be inserted into Figure 2 The interface circuit 206 sends and receives information to / from the processor 142 to assist in the evaluation and treatment of the thrombus. The interface circuit 206 receives electrical information from sensors on the expandable cage (in Figure 4) and transmits it to the computer 142, and transmits instructions from the computer to the catheter 100 to control the electrical output from the catheter to the thrombus. In some instances, the slender shaft 116 is conductive and electrically coupled to the conductor element 216, which is also electrically coupled to the interface circuit 206, so that the computer interface 206 allows the slender shaft 116 to deliver current from the battery 204 or power source to the thrombus, and / or receive electrical information about the clot sensed by the expandable cage on the distal end of the catheter. The slender shaft 116 can be formed of a conductive metal such as nitinol or stainless steel, or the slender shaft can be formed of a conductive polymer, or a combination of metal and polymer. Therefore, the battery or power source 204 is electrically coupled to the slender shaft 116 through the computer interface.

[0026] The distal end of the catheter shaft 116 may include a collar 214 or other coupling element for coupling an expandable cage (such as Figure 1 212, another device, or fluidly coupled to a source or container of a therapeutic agent or other fluid (e.g., saline, heparin, a thrombolytic agent or softener, etc.), so that the therapeutic agent can be delivered from the source through the lumen and the drug is delivered to the thrombus area at the distal end of the elongated shaft. Some examples of drugs can be thrombolytic agents that break up clots (e.g., streptokinase or urokinase), or other therapeutic agents that soften clots, or other therapeutic agents that have a desired therapeutic effect on clots. Some additional examples include thrombolytics, such as alteplase and tenecteplase, which are used to dissolve blood clots; calcium channel blockers, such as nimodipine, which are used to relieve vasospasm; antiplatelet drugs, such as aspirin, clopidogrel, which are used to prevent the formation of platelet clots after treatment; enzymes, such as elastase, to soften white clots; and neuroprotective drugs such as magnesium and nerinitide. This list of therapeutic agents is not intended to be limiting, and the physician may use any therapeutic agent required for a positive clinical outcome.

[0027] Figures 3A to 3B A catheter (eg, Figure 1 An example of a slender shaft 116 is shown in FIG. Figure 3A shows a side view of the elongated shaft, and Figure 3BA cross section of the elongated shaft is shown orthogonal to the longitudinal axis of the elongated shaft. Here, the elongated shaft 116 has a single lumen 302 extending from the proximal end of the elongated shaft to the distal end of the elongated shaft. As previously described, the elongated shaft 116 is coupled to an electro-drug unit, and a connector, such as a Luer hub, can be coupled to the lumen so that a therapeutic agent can be delivered to the thrombus through the lumen. The electro-drug unit and the connector are arranged in a Figures 1 to 2 is best shown in .

[0028] The elongated shaft 116 may include an inner shaft 304 and an outer shaft or coating 306 disposed on the inner shaft 304. As previously described, the inner shaft 304 may be conductive so that current can be delivered from the electro-drug unit along the elongated shaft via the expandable cage to the thrombus. Some examples of conductive elongated shafts include shafts formed of metals (e.g., nitinol or stainless steel, or conductive polymers, and combinations of metals and polymers). The outer coating or outer shaft 306 may be an insulating layer on the inner shaft 304. Additionally, in some examples, in addition to or instead of using an inner conductive shaft, a separate wire (not shown) may be used to deliver current from the electro-drug unit to the thrombus via the expandable cage.

[0029] The sensor wire 308 may be disposed on the inner shaft or on the wall of the elongated shaft and extend from the electro-drug unit to the expandable cage on the catheter. The sensor wire 308 may be disposed in a second lumen 310 in the wall of the elongated shaft. The sensor wire 308 may include insulation to prevent interference between the sensor signal carried on the sensor wire and any current delivered to the thrombus along the elongated shaft. Insulation may be provided by any material, technology, or any other means known in the art. Examples of insulating materials that can be used to insulate any wire in any device example disclosed herein include methacryloyloxyethyl phosphorylcholine (MPC). The sensor wire may be a high-conductivity wire (e.g., a low-impedance wire) so that any electrical sensor signal is transmitted without distortion or significant attenuation. This can be considered as performing an in vivo instant electrical biopsy of a clot.

[0030] The delivery of electrical current from a catheter to a thrombus, as well as additional details of using a sensing wire to sense characteristics of a thrombus, are discussed in greater detail below.

[0031] Figure 4 An example of a catheter distal end D that can be used to evaluate and treat thrombus is shown, such as previously described in Figure 1 As shown in .

[0032] The distal end of the elongated shaft 116 is aligned with the Figure 1 Thus, the structure and function of the expandable cage are similar to those of Figure 1The sensor wire 308 extends along the elongated shaft 116 and leaves the distal end of the elongated shaft and can then be connected to the expandable cage 410. The sensor wire can extend along or around the expandable cage in any desired manner. Here, the sensor wire extends spirally around the expandable cage along the entire length or a portion of the length of the expandable cage like a spiral corkscrew, and the distal end of the sensor wire is connected to the distal end of the expandable cage (or any desired position). The sensor wire can be insulated along its length to prevent interference with other electrical components on the catheter, and the insulation can be removed along a portion of the sensor wire to allow electrical contact with the thrombus. The sensor wire can be a single wire capable of measuring thrombus impedance (with the body as ground), or the sensor wire can be two side-by-side wires for measuring thrombus impedance along the length of the expandable cage. The sensor wire can be a single wire divided into two or more wires, which are arranged on the expandable cage to provide additional sensing locations. In an example where a single wire is used to measure impedance, the body can be used as a ground or return path. Here, a grounding plate such as a Bove plate can be placed under the patient's body, which is in electrical contact with the body to serve as a return path. In instances where two or more wires are used to measure impedance, one of the wires can be used to deliver current to the patient for impedance measurement, while the other wire can be used as a return path.

[0033] Additionally, as previously described, the elongated shaft can be electrically conductive, and thus current can be delivered from the electro-drug unit along the elongated shaft to the expandable cage electrically coupled to the elongated shaft. Thus, the expandable cage can be used to deliver current to the thrombus. The delivery of current to the thrombus by the expandable cage is separate from the electrical sensing wire that can measure the impedance of the thrombus, so that the two functions do not interfere with each other during operation. Multiple locations along the expandable cage can be insulated so that charge is only delivered from selected locations (e.g., nodes) along the expandable cage. The body can serve as a ground or return path for the circuit, and the Bove plate can be placed under the patient's body to create a circuit such as Figure 4 Alternatively, in other examples, two wires may be provided, one of which delivers the charge and the other serves as a return path.

[0034] Sufficient slack in the one or more wires and sufficient attachment of the one or more wires to the expandable cage is achieved to accommodate radial expansion and contraction of the expandable cage using techniques known in the art.

[0035] In use, the evaluation and treatment catheter can be used to treat a stroke patient having a blood clot blocking a vessel in the brain. An image of the blood clot is obtained using imaging techniques known in the art, and the image is analyzed to characterize the blood clot, such as size, shape, length, morphology, type of clot, etc. This information can be determined by a physician or using a computer processor and used to help determine treatment for the blood clot.

[0036] In addition, a catheter (such as the catheter disclosed herein) can be delivered to the thrombus to further evaluate and treat the thrombus. For example, once the catheter is delivered to the thrombus, the expandable cage can be radially expanded to engage with the thrombus to wrap around the thrombus. The sensor wire can be used to measure the impedance of the thrombus. The thrombus can be a red clot or a white clot. Red clots are rich in red blood cells, which have hemoglobin and therefore high iron concentration, which results in lower impedance than white clots. White clots are rich in white blood cells, fibers, and therefore do not conduct electricity like red clots, and therefore they have higher impedance. Measuring impedance helps doctors determine the type of clot present in a patient. This can be called performing an in vivo instant electrical biopsy of a clot.

[0037] If the clot is a white clot, an evaluation and treatment catheter may be used to deliver a therapeutic agent to help soften or dissolve the firm, hard, and fibrous white clot. Some examples of softening drugs that may be used include: thrombolytics, such as alteplase and tenecteplase, which are used to dissolve clots; antiplatelet drugs, such as aspirin, clopidogrel, which are used to prevent platelet clot formation after treatment; and enzymes, such as elastase, which are used to soften white clots. Again, the list of softening drugs is not intended to be limiting and other drugs may also be used.

[0038] Once softened, the expandable cage can be used to assist in clot removal by proximally retracting the expansion cage entangled with the clot.

[0039] In the case of red clots, they are softer than white clots and therefore do not necessarily require a therapeutic agent to soften them, but a softening or dissolving agent may optionally be used. However, the evaluation and treatment catheter may also be used to deliver a negative charge to the expandable cage, and the negative charge may help the iron-rich red clot adhere to the expandable cage that is entangled with the red clot, and thus when the expandable cage is retracted proximally, the clot is more likely to adhere to the expandable cage and be removed.

[0040] For red or white clots, the catheter may also be used to deliver some other therapeutic agent to the clot that will help restore vascular patency, or optionally deliver an electrical charge to the clot, or sense the conductivity of the clot to help diagnose the type of clot.

[0041] Figures 5A to 5K An example of a method for treating a patient suffering from a stroke caused by a blood clot in a cerebral artery is shown. This is not intended to be limiting and one skilled in the art will appreciate that the devices and methods disclosed herein can be used to treat clots or blockages in other vessels or other anatomical locations of the body. Any of the examples of evaluation and treatment catheters disclosed herein can be used in this example of a treatment method.

[0042] exist Figure 5A, a cerebral artery A is shown where a blood clot C has blocked the vessel, preventing or limiting the flow of oxygenated blood through the blockage, thereby causing a stroke due to ischemia. A clot may completely or partially block blood flow through a vessel.

[0043] exist Figure 5B In the present invention, a guidewire GW is introduced percutaneously into a blood vessel (usually an artery) and is advanced through the vessel, through the clot and distal to the clot. The guidewire can be introduced percutaneously into the vessel using standard procedures such as the Seldinger procedure or using surgical incision. Examples of access points may include the groin, wrist, neck, etc., and the guidewire can be advanced in any artery (e.g., femoral artery, carotid artery, radial artery, etc.) or any vessel such as a vein using known access techniques.

[0044] Once the guidewire is in place, it acts as a track over which the microcatheter is advanced to the treatment site. Figure 5C 8, a microcatheter 802 having an inner lumen is advanced distally over a guidewire GW in an affected artery A to a clot C. The microcatheter can be a single lumen catheter that provides a passage through which a stent retriever catheter (sometimes also referred to herein as a clot retriever or a device for removing an obstruction) can be advanced through the vasculature to the treatment site. The size of the microcatheter can be selected based on the vessel being treated. The stent retriever can be any of those disclosed herein.

[0045] Figure 5D The optional use of a sheath S is shown. Here, after the guidewire is inserted, a sheath (e.g., a guide sheath) can be advanced over the guidewire GW. The microcatheter is then advanced over the guidewire GW and through the lumen of the sheath S until the microcatheter is adjacent to or abuts the clot C. Thus, if a sheath is used, Figure 5D replace Figure 5C Once the microcatheter is properly advanced and positioned, the sheath can remain in place, retracted proximally to remove it but retain it in the vessel, or the sheath can be completely removed from the vessel. The microcatheter remains positioned adjacent the clot.

[0046] exist Figure 5E , microcatheter 802 is advanced through artery A so that its distal end passes through guidewire GW, through clot C, and is located distal to clot C. Once the microcatheter is delivered to the desired location, guidewire GW is retracted proximally and can be removed from the patient.

[0047] Once the microcatheter is positioned, a stent retriever catheter (such as any of those disclosed herein) can be introduced through an introducer port (not shown) at the vascular access point and advanced through the microcatheter toward the treatment area. Figure 1) can be provided on the stent retriever catheter for packaging and shipping purposes as well as for constraining the expandable cage. Thus, once the stent retriever has been inserted into the microcatheter, the outer sheath on the stent retriever can be retracted proximally and removed from the expandable cage. The microcatheter then constrains and prevents the expandable cage from self-expanding.

[0048] Fig. 5F A clot retriever catheter 806 is shown disposed in the microcatheter 802 and passed through the clot C. The clot retrieval device 806 is shown to include a distal portion of an expandable cage that passes through the clot C, an expandable capture cage 804, an elongated shaft 810, an optional proximal radiopaque marker or collar 812, and an optional distal radiopaque marker or collar 808. The clot retriever catheter 806 can be any of the examples disclosed herein.

[0049] The microcatheter 802 not only provides a channel for delivering the clot retrieval catheter 806, but also provides a constraint to maintain the expandable capture cage 804 in a collapsed configuration during delivery. Optional proximal and distal radiopaque markers 808, 812 allow the operator to visualize the position of the device and ensure that the expandable capture cage is set along the entire length of the clot C. The elongated shaft 810 can be a guidewire coupled to the expandable capture cage and allows the operator to push or pull the device along the artery A and through the microcatheter relative to the clot C. The elongated shaft can also be any of the examples of the elongated shafts disclosed herein, and they can be braided or otherwise reinforced or otherwise prepared to provide the desired pushability, or the elongated shaft can be a combination of a guidewire and any other elongated shaft disclosed herein to provide a pushable shaft that can conduct current or other electrical signals to or from the expandable cage and the electro-drug unit. The expandable capture cage may include any or all permutations or combinations of capture cage features described in any example of this specification or otherwise incorporated by reference.

[0050] Once the capture cage 804 has been properly positioned relative to the clot C, the microcatheter 802 is retracted proximally, such as Figure 5G , while the clot retrieval catheter remains stationary or slightly pushed out of the microcatheter. When the microcatheter 802 is removed from the expandable capture cage 804, it self-expands 814 to engage the clot C and the vessel wall. Because the wall of the capture cage is formed of closed cells, the wall of the cage is porous with holes extending through the wall to form a mesh-like cage wall that can expand into the clot C and wrap around the clot so that the clot is disposed within the cage and the struts of the cage are outside or mostly outside the clot. Figure 5G Partial expansion of the distal portion of the cage extending beyond the clot is shown.

[0051] exist Figure 5H802, further proximal retraction of the microcatheter 802 draws the entire capture cage out of the sheath so that it can self-expand and wrap around the clot C, thereby integrating the clot with the expandable cage. The capture cage can self-expand to juxtapose with the vessel wall. The entire clot C is now substantially within the expanded capture cage 814.

[0052] Any of the sensing or therapeutic techniques described above (e.g., measuring impedance, applying a negative charge to an expandable cage, delivering a therapeutic agent, etc.) may be performed at this point, or at any other desired point in this method instance.

[0053] Fig.5I It is shown that once the cage 814 self-expands and entangles the clot C, and after performing any of the sensing and / or therapeutic techniques described above (e.g., measuring impedance, applying a negative charge to the expandable cage, delivering a therapeutic agent, etc.), the entire clot retrieval device 806 can be retracted proximally by pulling the elongated shaft 810, which extends proximally out of the patient's body so that the operator can grasp and manipulate the proximal end. When the catheter is retracted proximally, the proximal retraction of the catheter also carries the entangled clot C and the cage 814. The catheter 806 and the clot are then retracted proximally along with the microcatheter 802 until it is removed from the patient. The expandable cage 814 can be retracted proximally so that the proximal end of the expandable cage approaches the distal end of the microcatheter, or the two ends can remain separated from each other. The elongated shaft 810 of the microcatheter and the clot retrieval catheter can both be retracted proximally together or separately.

[0054] Figure 5J An optional sheath S is shown that can be used to assist in the delivery of the clot retrieval catheter (see Figure 5D ). After the clot has been entangled in the cage 814, the microcatheter and cage 814 can optionally be retracted proximally into the sheath S and everything removed from the patient. Or optionally, the microcatheter and cage 814 can be partially retracted proximally and close to the distal end of the sheath S, but not necessarily all the way into the sheath S, and everything can then be removed from the patient.

[0055] Figure 5K The artery is shown after the clot, microcatheter, optional sheath, and clot removal device have been removed from artery A. Once the obstruction has been removed, the vessel is now patent again, and the tissue downstream of the clot will now receive oxygenated blood.

[0056] Other Applications - Vasospasm

[0057] As previously described above, blood vessels can go into spasm and this can restrict blood flow, which can lead to ischemia, including stroke. Any of the examples of the diagnostic and therapeutic devices disclosed herein can be used to treat blockages such as those caused by thrombi, but can also be used to treat vasospasm. Other uses of the devices and methods disclosed herein are also contemplated and are not limited to clot treatment or vasospasm.

[0058] For example, sometimes arteries in the brain go into spasm due to stimuli including trauma, blood, drugs, epileptic seizures, etc. This spasm causes functional narrowing of the artery and can reduce blood flow and lead to stroke. The treatment for such cases is to relieve spasm. There are several ways to achieve this, including-mechanical expansion of expandable members such as balloons, or radial expansion of expandable stent-like structures within the narrowed section to restore patency of the vessel, or delivery of drugs to relieve spasm (e.g., calcium channel blockers). Some examples of the present device disclosed herein can be used to mechanically support spasm or deliver drugs to the treatment area with a catheter. The radial expansion of the expandable cage can provide sufficient mechanical support to the vessel to relieve vascular spasm. In addition, some examples of the device disclosed herein can also be used to deliver electrical stimulation to spasm in order to relax the muscles in the vessel (e.g., the artery causing the spasm). Electrical stimulation can be combined with the mechanical support provided by the expandable cage and / or can be combined with the use of the device disclosed herein to deliver therapeutic agents to vascular spasm.

[0059] Thus, any of the examples of devices disclosed herein can be used to deliver one or more of the following treatments to spasms to help restore blood flow.

[0060] The expandable cage can be used as a mechanical support to help force the spasm open and keep it open until the spasm is relieved. Thus, any of the devices described herein are delivered to the area of ​​spasm and then the expandable cage is expanded to engage and open the restricted area to help restore flow.

[0061] The device can be used to deliver therapeutic agents through a lumen in the device, or the therapeutic agent can be carried on the expandable cage and eluted therefrom. This allows site-specific delivery of drugs to spasms. Some examples of drugs have been discussed previously above.

[0062] Any of some examples of the device can also be used to measure the electrical potential of an artery or other vessel in normal, unaffected areas as well as in areas of stenosis caused by spasm, and the device can thus be used to apply an opposite measured charge to relieve the spasm. Thus, in the above examples, rather than delivering a charge to a thrombus, a charge is delivered to a vessel experiencing spasm to relieve the stenosis.

[0063] Figures 6A to 6D The use of any of some examples of devices disclosed herein in treating intracranial arterial or venous spasm is shown. This is not intended to be limiting, and examples of such treatments may be used in any vessel or any other part of the body.

[0064] Fig. 6AA portion of the normal anatomy of the basilar arterial circle CW (Circle of Willis) is shown, which is a circulatory anastomosis of the major arteries supplying blood to the brain. Here, a portion of the basilar arterial circle is shown, including the basilar artery BA (basilarartery). The basilar artery is one of the major arteries supplying blood to the posterior part of the brain and the brainstem. Although there is some narrowing of the vessel in the antegrade direction of blood flow, there is no stenosis or significantly reduced diameter, and the side branches or bifurcations remain patent.

[0065] Figure 6B A small segment of the basilar artery BA is shown to have vasospasm, where the vessel narrows significantly, reducing blood flow, which can cause the patient to suffer a stroke due to insufficient oxygen being delivered to the brain. This can occur in a variety of disease states and is often accompanied by severe neurological symptoms, suggestive of an ischemic stroke.

[0066] Figure 6C An example of delivering any of the devices 602 disclosed herein to an area of ​​spasm through a vessel is shown. Once in a position that can be verified using fluoroscopy or any other imaging technique, a treatment regimen can be delivered. The treatment may include mechanical support from the expandable cage 604 once expanded; delivery of a drug (e.g., a calcium channel blocker or a sodium channel blocker) from the catheter device 602 to relieve spasm, which can relieve spasm caused by hypertonic smooth muscle in the artery or vein wall; or delivery of an electric current from the catheter device 602 to relieve spasm. The electrical potential at the inner wall of the artery or vein can be measured through the expandable cage. Such electrical potential measurements can inform the physician of the electrical state of the smooth muscle in the artery or vein wall. Once the difference in electrical potential is identified (when compared to a normal segment before or after the vasospasm segment), the diagnosis and subsequent management of vasospasm can be more effective and personalized.

[0067] Fig.6D It is shown that after the spasm is treated by any one or a combination of the treatment schemes disclosed above, the basilar artery returns to its normal diameter. Once blood flow is restored, the expandable cage, if it was expanded, can be deflated and the device can be removed from the patient, leaving a patent vessel.

[0068] Because some examples of the devices disclosed herein measure and provide information to the physician about the characteristics of the vessel to be treated, such as the nature of a thrombus or vasospasm, real-time feedback can be provided to the physician, allowing the physician to change the treatment based on changes in the characteristics of the vessel. For example, when a thrombus changes or a vasospasm changes during treatment, the treatment can be adjusted by changing the delivered drug, changing the support provided by the expandable cage, or by changing the electrical stimulation provided by the device. Thus, an optimized, real-time feedback-based treatment (e.g., electrical stimulation) can be provided to the patient to relieve the thrombus or vasospasm. In some examples, the treatment is manually changed by a physician or technician, while in other examples, the treatment is automatically changed by the device or system itself.

[0069] Notes and Examples

[0070] The following non-limiting examples detail certain aspects of the subject matter to address challenges and provide the benefits discussed herein, among others.

[0071] Embodiment 1 is a device for treating a thrombus or spasm in a patient's blood vessel, the device comprising: an elongated shaft having a proximal end, a distal end, and an inner cavity extending therebetween; an electro-drug unit coupled to the proximal end of the elongated shaft, wherein the electro-drug unit is configured to facilitate evaluation and treatment of the thrombus or the spasm; an expandable cage coupled to the distal end of the elongated shaft, the expandable cage having a contracted configuration for delivery to the thrombus or the spasm through a vessel, and an expanded configuration for wrapping around the thrombus or supporting the spasm; and an electrical element coupled to the expandable cage, the electrical element being configured to sense characteristics of the thrombus or the spasm or being configured to provide treatment for the thrombus or the spasm.

[0072] Embodiment 2 is the device of embodiment 1, wherein the electro-drug unit is releasably coupled to the proximal end of the elongated shaft.

[0073] Embodiment 3 is the device of any one of embodiments 1-2, wherein the electro-drug unit comprises an electronic circuit operatively coupled to a processor, the electronic circuit being configured to facilitate evaluation and treatment of the thrombus or the spasm.

[0074] Embodiment 4 is the device of any one of embodiments 1-3, wherein the electro-drug unit further comprises a housing configured to house the electronic circuit.

[0075] Example 5 is the device of any one of Examples 1 to 4, wherein the electrical element comprises a conductive wire coupled to the expandable cage, the conductive wire being configured to measure impedance of the thrombus or to measure electrical potential in or near the spasm.

[0076] Embodiment 6 is the device of any one of embodiments 1 to 5, wherein the elongated shaft is formed of a conductive material, the elongated shaft forms at least a portion of the electrical element and is configured to deliver an electrical charge to the expandable cage.

[0077] Embodiment 7 is the device of any one of embodiments 1 to 6, wherein the device is configured to provide optimized electrical stimulation based on real-time feedback to relieve vasospasm.

[0078] Embodiment 8 is a system for treating thrombus or spasm in a patient, the system comprising: the device described in any one of embodiments 1 to 7; an imaging system configured to provide an image of the thrombus or the spasm; and a processor configured to evaluate the image of the thrombus or the spasm and provide a characterization of the thrombus or the spasm, and wherein the processor controls an electro-drug unit to deliver customized treatment to the thrombus or the spasm.

[0079] Example 9 is the system of Example 8, further comprising a container of a therapeutic agent coupled to the lumen fluid, wherein the therapeutic agent is configured to dissolve, soften, or otherwise provide a desired effect on the thrombus, or wherein the therapeutic agent is configured to relieve the spasm.

[0080] Example 10 is a method for evaluating or treating a thrombus or spasm in a patient's vessel, the method comprising: advancing a catheter having an elongated shaft and an expandable cage through the vessel toward the thrombus or the spasm; sensing characteristics of the thrombus or the spasm with the catheter; and based on the sensed characteristics, evaluating the thrombus or the spasm and determining a treatment for removing or reducing the thrombus, or for alleviating the spasm and restoring patency of the vessel.

[0081] Example 11 is the method of Example 10, wherein the sensing comprises measuring impedance of the thrombus with the catheter to characterize the thrombus, or measuring electrical potential in or near the spasm.

[0082] Example 12 is the method of any one of Examples 9 to 11, wherein the treatment comprises radially expanding the expandable cage to wrap around the thrombus, the method further comprises proximally retracting the expandable cage to remove the thrombus from the vessel, or wherein the treatment comprises radially expanding the expandable cage to support the spasm.

[0083] Embodiment 13 is the method of any one of embodiments 9 to 12, wherein the treatment comprises electrically charging the expandable cage to facilitate capture of the thrombus by the expandable cage, or electrically stimulating the spasm.

[0084] Embodiment 14 is the method of any one of embodiments 9 to 13, wherein the treatment comprises delivering a therapeutic agent from the catheter to the thrombus or the spasm, the therapeutic agent being configured to dissolve, soften, reduce spasm, or otherwise provide a desired effect on the thrombus or spasm.

[0085] Example 15 is the method of any one of Examples 9 to 14, further comprising imaging the thrombus or the spasm, and evaluating the image of the thrombus or the spasm to determine a treatment for removing the thrombus or alleviating the spasm.

[0086] Embodiment 16 is the method of any one of embodiments 9 to 15, further comprising providing optimized electrical stimulation based on real-time feedback to relieve vasospasm.

[0087] In Example 17, the device, system or method of any one or any combination of Examples 1 to 16 may be optionally configured so that all of the elements or options described are available for use or selectable therefrom.

[0088] The above detailed description of the invention includes reference to the accompanying drawings, which form a part of the detailed description of the invention. The accompanying drawings show some specific embodiments in which the present invention can be implemented by way of example. These embodiments are also referred to as "embodiments" in this article. Such embodiments may include elements other than those shown or described. However, the inventors also consider embodiments in which only those elements shown or described are provided. In addition, the inventors also consider embodiments using any combination or arrangement of those elements (or one or more aspects thereof) shown or described herein with respect to a specific embodiment (or one or more aspects thereof) or with respect to other embodiments (or one or more aspects thereof).

[0089] In the event of an inconsistency in usage between this document and any document incorporated by reference, the usage in this document controls.

[0090] In this document, as is common in patent documents, nouns without quantifiers are used to include one or more than one, independent of any other instance or usage of "at least one" or "one or more". In this document, unless otherwise specified, the term "or" is used to refer to a non-exclusive or, so that "A or B" includes "A but not B", "B but not A", and "A and B". In this document, the terms "including" and "wherein" are used as the plain English equivalents of the corresponding terms "including" and "wherein". In addition, in the appended claims, the terms "including" and "including" are open-ended, that is, systems, devices, articles, compositions, formulations, or methods that include elements other than those listed after such terms in the claims are still considered to fall within the scope of the claims. In addition, in the appended claims, the terms "first", "second", and "third", etc. are used only as markers and are not intended to impose numerical requirements on their objects.

[0091] The above description is intended to be illustrative, not restrictive. For example, the above embodiments (or one or more aspects thereof) can be used in combination with each other. After reviewing the above description, other embodiments can be used, for example, by those of ordinary skill in the art. An abstract is provided to allow the reader to quickly determine the nature of the technical disclosure. It should be understood that the submitted abstract is not used to interpret or limit the scope or meaning of the claims. In addition, in the above detailed description of the invention, multiple features can be combined together to streamline the disclosure. This should not be interpreted as meaning that the disclosed features that are not claimed for protection are essential to any claim. On the contrary, the subject matter of the present invention may be less than all the features of a specific disclosed embodiment. Therefore, the attached claims are incorporated into the detailed description of the invention as examples or embodiments, wherein each claim is individually used as an independent embodiment, and it is expected that such embodiments can be combined with each other in multiple combinations or arrangements. The scope of the present invention should be determined with reference to the attached claims and the full scope of the equivalent schemes given by such claims.

Claims

1. A device for treating a thrombus or spasm in a patient's blood vessel, the device comprising: an elongated shaft having a proximal end, a distal end, and a lumen extending therebetween; an electro-drug unit coupled to the proximal end of the elongated shaft, wherein the electro-drug unit is configured to facilitate evaluation and treatment of the thrombus or the spasm; an expandable cage coupled to the distal end of the elongated shaft, the expandable cage having a collapsed configuration for transvascular delivery to the thrombus or the spasm, and an expanded configuration for entangling the thrombus or supporting the spasm; and An electrical element is coupled to the expandable cage, the electrical element being configured to sense a characteristic of the thrombus or the spasm or to provide treatment for the thrombus or the spasm.

2. The device of claim 1, wherein the electro-drug unit is releasably coupled to the proximal end of the elongated shaft.

3. The device of claim 1, wherein the electro-drug unit comprises an electronic circuit operatively coupled to a processor, the electronic circuit being configured to facilitate evaluation and treatment of the thrombus or the spasm.

4. The device of claim 3, wherein the electro-drug unit further comprises a housing configured to house the electronic circuit.

5. The device of claim 1, wherein the electrical element comprises a conductive wire coupled to the expandable cage, the conductive wire being configured to measure impedance of the thrombus or to measure an electrical potential in or near the spasm.

6. The device of claim 1, wherein the elongated shaft is formed of a conductive material, the elongated shaft forming at least a portion of the electrical element and configured to deliver an electrical charge to the expandable cage.

7. The device of claim 1, wherein the device is configured to provide optimized electrical stimulation based on real-time feedback to relieve vasospasm.

8. A system for treating thrombosis or spasm in a patient, the system comprising: The device according to claim 1; an imaging system configured to provide an image of the thrombus or the spasm; and A processor is configured to evaluate the image of the thrombus or the spasm and provide a characterization of the thrombus or the spasm, and wherein the processor controls the electro-drug unit to deliver customized therapy to the thrombus or the spasm.

9. The system of claim 8, further comprising a container of a therapeutic agent coupled to the lumen fluid, the therapeutic agent being configured to dissolve, soften, or otherwise provide a desired effect on the thrombus, or wherein the therapeutic agent is configured to reduce the spasm.

10. A method for evaluating or treating thrombosis or spasm in a patient's vessel, the method comprising: advancing a catheter having an elongated shaft and an expandable cage through a vessel toward the thrombus or the spasm; sensing a characteristic of the thrombus or the spasm using the catheter; as well as Based on the sensed characteristics, the thrombus or the spasm is evaluated and a treatment is determined for removing or reducing the thrombus, or for alleviating the spasm and restoring patency of the vessel.

11. The method of claim 10, wherein the sensing comprises measuring impedance of the thrombus with the catheter to characterize the thrombus, or measuring electrical potentials in or near the spasm.

12. The method of claim 10, wherein the treatment comprises radially expanding the expandable cage to entangle the thrombus, the method further comprising proximally retracting the expandable cage to remove the thrombus from the vessel, or wherein the treatment comprises radially expanding the expandable cage to support the spasm.

13. The method of claim 10, wherein the treatment comprises electrically charging the expandable cage to facilitate capture of the thrombus by the expandable cage, or electrically stimulating the spasm.

14. The method of claim 10, wherein the treatment comprises delivering a therapeutic agent from the catheter to the thrombus or the spasm, the therapeutic agent being configured to dissolve, soften, reduce spasm, or otherwise provide a desired effect on the thrombus or spasm.

15. The method of claim 10, further comprising imaging the thrombus or the spasm and evaluating the image of the thrombus or the spasm to determine a treatment for removing the thrombus or alleviating the spasm.

16. The method of claim 10, further comprising providing optimized electrical stimulation based on real-time feedback to relieve vasospasm.

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