Intravascular devices for traversing obstacles within blood vessels

Abstract

To provide an endovascular apparatus which has advanced a conventional endovascular guide wire design where mechanical vibrations are transmitted to a distal end via a wire, and existing activated guide wire and catheter system.SOLUTION: An endovascular apparatus for crossing through an obstruction in a blood vessel comprises an elongate endovascular wire 14 and a coupling for transmitting ultrasonic energy along the wire 14 from an ultrasonic energy source to an active tip at a distal end of the wire 14. The coupling is arranged to couple the source to the wire 14 at any of a plurality of discrete operational positions along the length of the wire 14 for said transmission of ultrasonic energy to the active tip.SELECTED DRAWING: Figure 27a

Description

Background Art

[0001] Ischemia refers to insufficient blood supply to the organs in the body. In atherosclerotic blood vessels, ischemia occurs as a result of the blood vessels being blocked by obstacles resulting from lesions in the vessel wall, atherosclerotic plaques, or emboli caused by other reasons. Atherosclerotic plaques are composed of materials whose structure gradually hardens over time.

[0002] By partially or completely blocking the blood vessels, the obstruction restricts the blood flowing to the tissue distal to the obstruction, causing cell death and a rapid deterioration of the tissue's health condition.

[0003] The preferred method for treating such obstructions is by minimally invasive endovascular angioplasty. In these procedures, a small-diameter treatment device is introduced into the vasculature, navigated through the lumens of veins and arteries to the obstruction, and deployed at the lesion site to restore patency. These procedures for revascularizing occlusions in coronary and peripheral arteries in the treatment of chronic atherosclerotic plaques can also be used for the treatment of acute thrombotic occlusions, thrombi, or occlusive blood clots.

[0004] The anatomical structures where these procedures are performed include, but are not limited to, the coronary arteries, neurovascular arteries, and peripheral arteries that supply the lower extremities. Different anatomical structures are associated with different lesions. Lesions found in various peripheral vasculatures pose different types of challenges than those found in the coronary arteries. The iliac artery, femoral artery, popliteal artery, and infrapopliteal artery have various tortuosities and are often considerably smaller than the coronary artery or the neurovascular system. However, these arteries are susceptible to the effects of extensive calcification, which poses a serious obstacle to the success of endovascular procedures.

[0005] In endovascular procedures, an artery is selected and employed to gain access to the vascular system. The selection is based on the artery's ability to accommodate the passage of the intended diagnostic or therapeutic device to the target site, as well as to the extent that tissue and patient trauma can be minimized.

[0006] Peripheral artery revascularization procedures often involve surgical incision and puncture of the femoral, popliteal, and ankle arteries, commonly known in medical terminology as the Seldinger procedure. Once access is established, an introducer wire and introducer sheath are inserted into the vessel and secured at the site. This sheath acts as a port for device introduction, withdrawal, and replacement, minimizing arterial tissue dissection. Next, a guide catheter and guidewire are introduced into the artery to provide further protection and assist in device navigation to the target site.

[0007] The guidewire is carefully pushed along the lumen of the blood vessel to navigate to the site of the obstruction, taking care not to cause trauma to the vessel wall. In a successful procedure, the guidewire is then pushed to the other side of the obstruction or through it and held in place, serving as a guide for diagnostic or therapeutic devices such as balloon catheters and stents to track over it to the site of the occlusion. Guidewires are also used in other minimally invasive procedures to introduce other devices and instruments into blood vessels or other cavities in the body to enable examination, diagnosis, and different types of treatment.

[0008] In balloon angioplasty, a balloon catheter is guided into the blood vessel over a guidewire and navigated to the occluded area. The balloon is then inflated to crush or decompose the occluding material, restoring blood flow. A stent may be placed over the area of ​​the decompressed lesion to act as a scaffold to maintain vascular patency.

[0009] Visualization of the progression of guidewires and other diagnostic and therapeutic devices advanced through anatomical structures is typically performed using X-rays or duplex ultrasound. For other anatomical structures, MRI is becoming increasingly popular.

[0010] Other medical procedures that use guidewires as mentioned above include gastrointestinal, urological, and gynecological procedures, all of which require the creation of a passage through an obstruction to facilitate the passage of larger, often more cumbersome devices to the lesion site or other target tissues distal to the lesion within the body.

[0011] Guidewires are key to therapeutic interventions and are manufactured from different materials, most commonly stainless steel and NiTi (nitinol), and come in many different designs. Their manufacture involves modifying the microstructural morphology of the material, for example, by cold working the material while forming it into a wire, and then machining the wire to different dimensions to achieve the desired performance. As an example, a specific taper can be machined along the length of the wire to produce a differential degree of flexibility along the length of the wire. Thus, at its distal end, the wire has sufficient flexibility to conform to the shape of the blood vessel and strength to transmit force to the tip ("tip strength") or force to traverse the lesion.

[0012] The structure of these devices typically includes thin coils that may extend along the entire length of the wire, or into individual sections, most typically the distal section. These coils facilitate force transmission through tapered sections, increasing the force that can be transmitted along the entire length of the wire. They also allow the wire to easily conform to the shape of blood vessels and track through tortuous anatomical structures that may be encountered, particularly within the anatomical structures of the coronary arteries and neurovascular systems.

[0013] Wires are available in a variety of outer diameters associated with the anatomical structure being treated. Wires on the order of 0.010 inches (approximately 0.25 mm) in diameter are commonly used in the neurovascular system, while wires with outer diameters of 0.014 to 0.018 inches (approximately 0.36 mm to 0.46 mm) are typically used for coronary artery applications. These 0.014-inch and 0.018-inch wires are also used in many peripheral vascular systems, as well as in the anatomical structures of the foot and tibia, typically below the popliteal fossa. When accessing and treating large-diameter, straight vessels affected, such as the ilium, aorta, and thoracic vessels, wires with a standard outer diameter of 0.035 inches (approximately 0.89 mm) may be used. Wires with an outer diameter of 0.016 inches (approximately 0.4 mm) and 0.018 inches (approximately 0.46 mm) are common when accessing blood vessels in the femur, popliteal fossa, and subpopliteal fossa.

[0014] The length of wires used in endovascular procedures also varies depending on the distance they are likely to operate over. For example, wires typically 750mm to a maximum of 900mm in length are used in many peripheral applications where they may be introduced into anatomical structures of the femur or popliteal fossa, or track to and pass through occlusions within the ipsilateral iliofemoral-popliteal and infrapopliteal arteries. Wires used in contralateral and coronary artery applications tend to be on the order of 1200mm, 1500mm, or 1700mm. In fact, wires that can be tracked contralaterally may be even longer, perhaps on the order of 2000mm to 2250mm or 2500mm.

[0015] These conventional endovascular wires are passive in the sense that they do not transmit any energy other than that applied by the clinician. They come in a variety of structures and designs to facilitate access to and traverse lesions within different anatomical structures and for different devices. However, very often, occlusions are too difficult for conventional wires to traverse.

[0016] In the case of peripheral arteries, these barriers are often made of materials that are too resistant to allow wire passage, and in these cases, endovascular procedures take considerably longer to perform, often require more devices to traverse the lesion, or very often, are simply abandoned.

[0017] In over 50% of peripheral artery cases, particularly in the popliteal, tibial, and peroneal arteries, the blood vessels are completely occluded by the lesion. In approximately 30% of cases, the target lesion is severely calcified. These calcified lesions consist of rigid, inelastic segments, typically 3-5 cm in length, within longer, more widespread diffuse lesions that are, on average, on the order of 20 cm in length. Selecting the appropriate treatment for these lesions requires insights into their length and composition, which are not readily available from conventional imaging.

[0018] If the guidewire cannot traverse the lesion within the blood vessel, it significantly impacts the likelihood of the procedure's success. The inability of the guidewire to traverse the lesion within the blood vessel can hinder desirable subsequent procedures such as balloon angioplasty and stent placement, limiting the ability to treat the patient.

[0019] Occlusion of distal infrapopliteal vessels, or anterior and posterior tibial and peroneal arteries, results in an ischemic response to wounds and trauma, leading to refractory ulceration of wounds and cuts and other tissue damage. This predictable response makes surgical intervention less attractive and increases the need for endovascular solutions for chronic total occlusion (CTO).

[0020] The fact that conventional wire designs often fail to traverse refractory lesions has led to the development of advanced minimally invasive endovascular surgical techniques using conventional guidewires and balloons over the past 20 years. The procedures are technically challenging and require considerable skill and training, as well as specialized devices designed to enable them to be performed more efficiently. Techniques such as subintima and retrograde approaches have evolved, and re-entry devices have emerged to assist in the procedures.

[0021] Subintima techniques bypass a lesion by forming a new pathway that tunnels along the intima, around the media, over the length of the lesion, and re-enters the blood vessel distally. These pathways are established by balloon dilation and stent placement to maintain patency. Re-entry devices have been developed to facilitate these procedures.

[0022] Retrograde techniques utilize the softer distal cap of the occlusion, which is easier to traverse than the calcified proximal cap encountered with antegrade (femoral) approaches. In these retrograde techniques, access is obtained via a vessel distal to the lesion in the foot or ankle in the case of peripheral disease, or via a collateral (usually septal) vessel in the anatomical structures of the coronary arteries. These procedures are more complex, require higher skill, and take much longer to perform.

[0023] In peripheral subiliac procedures, time is spent attempting a conventional (antegrade) approach before escalating to a retrograde approach to traverse the lesion, and then escalating via a wire in further antegrade attempts.

[0024] In resource-constrained healthcare systems, increasing demand is making the adoption of these life-saving, limb-saving endovascular techniques a challenge for the clinical community. They undoubtedly offer the best patient outcomes, reduce the consumption of hospital and community care resources, and provide better financial outcomes for healthcare systems. However, their adoption is limited by the widespread recognition of these outcomes, the limited hospital and clinical resources, and the considerable level of clinical training and practice required for current techniques.

[0025] Conventional intravascular guidewires are passive mechanical devices without active components. They are actuated by their proximal end being pushed, pulled, and torqued to navigate to the occlusion site, and then pushed through or around the occlusion. Their design balances surface properties, rigidity, and flexibility to optimize how they navigate and act when delivering treatment. These passive wires may not function as intended as guidewires or are limited when attempting to traverse nearly or completely blocked occlusions that may be significantly calcified.

[0026] A brief description of prior art A wide range of approaches using ultrasonic vibrations transmitted through small-diameter catheters and assemblies are established in both expired and recent prior art, as exemplified in U.S. Patent No. 3,433,226. U.S. Patent No. 5,971,949 describes the transmission of ultrasonic energy through waveguides of different configurations and tip shapes. U.S. Patent No. 5,427,118 describes an ultrasonic guidewire system, but does not discuss in detail the proximal shape of the wire or how it facilitates subsequent devices via over-the-wire methods.

[0027] Many current single transducer systems are instead ultrasonic - activated catheters that include a wire member for agitating and ablating material rather than an ultrasonic - activated guide wire. Such systems are described in U.S. Patent No. 6,855,123 and U.S. Patent No. 4,979,939. These catheters themselves require a separate passive guide wire to assist them in navigating and thus are tools for facilitating the crossing of a separate guide wire over an obstruction. U.S. Patent No. 9,629,643 shows systems with various distal tip configurations, but all require a separate guide wire for access.

[0028] These devices are aimed at providing an alternative method for revascularization and are described as atherectomy devices. They are not specified to cross lesions in order to facilitate the delivery of a device to effect revascularization by conventional PTA and PTCA treatment devices.

[0029] In the art, these ultrasonic devices and recanalization wire devices are associated with the claim of improving clinical atherectomy procedures. They provide or effect atherectomy by improving revascularization and reducing lesions by removing plaques that form the lesions.

[0030] Many prior art disclosures mention a reduced likelihood of vascular dissociation as a result of the operation of such devices that are non - invasive to soft, pliable tissue. Some facilitate the movement of a wire through the vasculature without relying on hydrophobic or hydrophilic coatings.

[0031] The potential for ultrasonic intravascular device vibrations to reduce the likelihood of vasospasm, a harmful event that can occur during any angioplasty procedure using conventional devices, has also been repeatedly mentioned in the art. This therapeutic advantage is thought to result from the effect of the vibrations of the wire that massages the tissue. See U.S. Patent No. 5,324,255.

[0032] Early researchers of these revascularization devices reported in the published literature how their effectiveness was affected by contact with tissue and described how to increase the power of the system to overcome losses by manually adjusting the voltage in a stepwise increase to overcome the losses. This indicates that some means for overcoming the effects of losses are needed, such as changing the voltage to increase the amplitude or changing the frequency.

[0033] In later and current designs, the ultrasonic generator system has become a large unit and is scaled to generate and control the pulse wave. Today's electronics technology may make it possible to package such a system in a smaller form, but the cost of miniaturization is contrary to this. Also, considerations of practical utility mean that known systems generally include separate elements. For example, many systems are designed with the signal generator housed in a separate unit from the transducer, and some are attached to large trolley units that take up a significant amount of space in the clinical environment. All of U.S. Patent No. 6,450,975, U.S. Patent Application Publication No. 2008 / 0228111, and U.S. Patent No. 9,282,984 describe such systems.

[0034] In the prior art, many systems describe semi-automatic control of amplitude via a feedback loop that monitors current. This provides a means to achieve maximum tip displacement by modulating voltage through the passage of the device through the vascular system and when tunneling through lesions. These systems do not directly correlate this modulation to tip displacement and tunneling effects, or to the composition or characteristics of the lesion.

[0035] Angiosonic's U.S. Patent No. 6,577,042 describes current-based modulation of output amplitude in an algorithm for interrogating transducer current over a narrow frequency range. This allows power to be maintained at a constant level, current and voltage to be monitored over a narrow frequency range to detect faults in the sonotrode, which is the activated component, and to confirm an optimized output frequency.

[0036] Soundbite's International Publication No. 2018 / 002887 describes different approaches to generating focused wave profiles using multiple transducers or wave focusing. These also require a large physical unit. The unit creates the output ultrasound through the orchestration of sound waves generated by transducers within the device by acquiring at least two different component waves and combining them in a waveguide to form the desired output wave. All of these methods require substantial data acquisition and computer systems to yield a solution.

[0037] The method of coupling a mechanical waveguide or transmission member to a horn is important, and many connection methods have been disclosed. U.S. Patent No. 4,572,184 discloses a method using a screw connector in which a wire is held within a screw. In addition to internal connection mechanisms, there are numerous patents associated with design features that allow users to interact with these mechanisms, including U.S. Patents No. 6,508,781, 5,971,949, 5,417,672, and 9,433,433.

[0038] Lateral constraints are also mentioned to optimize the way the wire moves through the vessel. The literature also mentions providing strain relief at the transmission junction.

[0039] The properties of the wire are addressed in terms of its shape or form, with solid wires being the most common, as disclosed in U.S. Patent No. 6,589,253, although hollow structures are also proposed, as described in U.S. Patent No. 4,538,622. Modification of the wire via a taper is suggested to optimize resonance along the length of the wire, as well as to drive displacement at the distal end. The composition of the material is also important in terms of type, combination, and composite material structure, as disclosed, for example, in U.S. Patent No. 8,500,658 and U.S. Patent No. 5,397,301, respectively.

[0040] Ultrasound-activated catheter and wire systems have been considered in the past as methods for atherectomy and for preparing blood vessels for angioplasty. Several products have been commercially available in the past, some still on the market, and several new systems have recently entered the market. These various types of catheters are referenced below.

[0041] These catheter and wire systems often include a) an ultrasonic generator that converts a mains power source into an ultrasonic waveform defined by voltage amplitude and frequency, b) an ultrasonic transducer, and often an amplifying horn that converts electrical energy into high-frequency mechanical vibrations defined by vibration frequency and amplitude, and c) a small-diameter waveguide coupled to the horn that transmits the mechanical vibrations to the distal end of the wire. The goal is for the distal end of the wire to vibrate at a desired amplitude and frequency to cauterize the material and ultimately facilitate revascularization or recanalization of blood vessels and anatomical structures throughout the body.

[0042] Tissues and materials near the distal tip are affected by a combination of ultrasonic movement of the tip and its direct mechanical delamination, cauterization and cavitation from the pressure wave component, and acoustic streaming that removes cauterized material from the zone around the tip. [Prior art documents] [Patent Documents]

[0043] [Patent Document 1] U.S. Patent No. 3,433,226 [Patent Document 2] U.S. Patent No. 5971949 [Patent Document 3] U.S. Patent No. 5427118 [Patent Document 4] U.S. Patent No. 6855123 [Patent Document 5] U.S. Patent No. 4979939 [Patent Document 6] U.S. Patent No. 9629643 [Patent Document 7] U.S. Patent No. 5324255 [Patent Document 8] U.S. Patent No. 6450975 [Patent Document 9] U.S. Patent Application Publication No. 2008 / 0228111 [Patent Document 10] U.S. Patent No. 9,282,984 [Patent Document 11] U.S. Patent No. 6577042 [Patent Document 12] International Publication No. 2018 / 002887 [Patent Document 13] U.S. Patent No. 4572184 [Patent Document 14] U.S. Patent No. 6508781 [Patent Document 15] U.S. Patent No. 5,417,672 [Patent Document 16] U.S. Patent No. 9433433 [Patent Document 17] U.S. Patent No. 6,589,253 [Patent Document 18] U.S. Patent No. 4,538,622 [Patent Document 19] U.S. Patent No. 8500658 [Patent Document 20] U.S. Patent No. 5397301 [Overview of the project] [Means for solving the problem]

[0044] This invention represents a disruptive advancement over conventional intravascular guidewire designs and existing activated guidewire and catheter systems, in which mechanical vibrations are transmitted to the distal tip via the wire.

[0045] Aspects of the concept of the present invention are described in the appended claims.

[0046] An ultrasound system is disclosed which induces vibrations within a customized endovascular surgical wire device and interrogates and applies artificial intelligence and / or smart electronics to provide feedback within the system for use in navigating intravascular occlusions, traversing occlusions, and optimizing the device's performance when characterizing occlusions.

[0047] The present invention provides a device intended for rapidly penetrating and traversing any occlusion of any composition within any artery or other blood vessel. The device can be used in a standalone procedure to regenerate blood flow and restore blood flow in applications such as the foot. However, the device is most advantageously used to facilitate the subsequent transport of intravascular diagnostic and therapeutic devices to provide and support revascularization of blood vessels.

[0048] Ultrasound-activated guidewire devices are intended to 1) traverse complex, calcified vascular occlusions as a standalone procedure or as an activated or passive guidewire, and 2) provide a conduit that allows for the passage of an auxiliary device, resulting in vascular revascularization and scaffolding.

[0049] In literature, patents, and marketed products, all concepts of systems activated by wire or ultrasound are mounted and clamped to the proximal end of the device.

[0050] In embodiments of the present invention, transmission or activation is provided that is performed at intervals anywhere along the length of the wire. This allows the activation device to be moved along the length of the wire or left in a specific location, for example, near the activation port, and the wire to be moved in and out of the device to prepare it for traversal of the therapeutic device.

[0051] In a sense, the present invention relates to a system comprising three interconnected components: a) a compact housing, as well as components functioning as an ultrasonic source and connector; b) an active transverse wire assembly for entering the anatomical system and transmitting energy to an active distal tip; and c) a signal acquisition, processing, and communication chipset. The compact housing unit has an ultrasonic generator, ultrasonic transducer, horn, and control unit, all housed together in a portable, compact housing unit designed to excite the intravascular transverse wire, monitor and modulate the system's excitation, and connect via a coupling unit resulting in the transsection and characterization of the intravascular occlusion. An onboard signal acquisition and processing chipset can acquire and control the excitation of the signal generator and provide communication of the output from the system to its user and / or an external data acquisition system.

[0052] The present invention relates to a device for activating an intravascular transverse wire, advantageously along its entire length, with ultrasound. When coupled and separated from the activation unit via the disconnection means of the present invention, the transverse wire has a nominal outer diameter that allows the wire to function as a primary transverse device. The activation unit can be coupled to and disconnected from the wire, and can also be coupled at intervals along the length of the wire. When coupled and separated, the activation unit also facilitates the passage of therapeutic devices, such as atherectomy vascular preparation devices, angioplasty catheters, and stents, over the wire, to the occluded site.

[0053] The controller can monitor current and voltage measurements, as well as frequency and amplitude measurements of incident, reflected, and standing waveforms, thereby allowing estimation of distal tip displacement. Modulation of these variables can be monitored as the wire traverses anatomical structures and different types of occlusions, including calcified chronic total occlusions. Determining calcified versus non-calcified lesions, and determining the duration or length of calcified segments, are key in some aspects of the present invention.

[0054] The signal used to drive the ultrasonic generator can be pulsed or modified to reduce heating and optimize the analysis and matching of the offset at the resonant frequency. Pulse modulation of voltage over a narrow frequency range can activate the transverse wire. A digital signal processor unit interrogates the measured values ​​and provides feedback, allowing for interpretation and comparison of the relative contributions of losses due to anatomical tortuosity when navigating the site and losses resulting from passing through the occlusion.

[0055] Using specific algorithms for each standard wire type, the diameter can be estimated based on different levels of frequency and power under the conditions associated with the procedure, as well as the deflection of the distal tip when excited by the device configuration. The algorithm can estimate the diameter along the length of the tunnel section through the occlusion.

[0056] The system of the present invention can process data obtained from measurements showing ultrasonic waveforms when ultrasonic waveforms are generated, when they pass through a transmission member, when resonant vibration conversion occurs, and when reflected waveforms are attenuated by the transmission member while passing through vascular systems and occlusions. This data is processed or manipulated by an onboard algorithm to perform actions to convert the raw data into treatment-related outputs.

[0057] When the modulation of the transmitted signal is monitored and analyzed, the system of the present invention can increase the system's power by adjusting, in some cases automatically, the energy loss of the system through voltage control, and compensate for the energy loss encountered in the wire as it passes through the vascular system to the occlusion. The system can distinguish these losses from additional losses as the wire passes through the occlusion and can compensate for the latter loss to maintain the displacement at the distal tip.

[0058] The measured parameters and variables can be numerically manipulated to determine the rate of change of their measurements relative to each other and to other parameters. The system of the present invention can characterize the properties of the material blocking the vessel by numerically comparing and interpreting the difference between these calculated values ​​from the active system and a predetermined set of values. Optionally, the energy can be manually controlled by an override controller that allows the user to increase the power of the system and thus increase the level of energy for driving the waveguide. Means that provide manual pulse override through current or voltage adjustment can be used to address sudden losses in the system due to unexpected events or interference with the wires immediately or proactively.

[0059] The output can be presented visually on a small display, or it can be presented via tactile or auditory hardware, such as a haptic interface, which is onboard and accessible to the user and can be viewed.

[0060] Optionally, the active transverse wire assembly can be used in passive mode without ultrasonic activation, or the wire can be mechanically coupled to an ultrasonic transducer and acoustic horn within a housing unit to transmit ultrasonic vibrations, and then the wire can be disconnected from the housing unit to return the wire to its configuration for subsequent procedures.

[0061] The active wire assembly can be connected by means of connecting it to an acoustic horn and a compact housing unit in a manner that enables efficient transmission of ultrasonic vibrations to the wire assembly. Geometrically shaped proximal tips are optimized to be easily installed, loaded, and tight-fitted within the coupling connector, facilitating rapid loading and unloading, as well as faithful energy transmission through the wire.

[0062] The proximal end of the wire can be machined to a shape that allows it to be installed within the acoustic horn and engage with the acoustic horn in direct contact. Once the wire is in this position, the secondary mechanism can be clamped or locked in a position that aligns with the circumferential surface of the locking unit, and the wire remains in place until the mechanism is released.

[0063] Custom active transverse wire assemblies can be presented in a system having integrated mounting bosses that allow portions to be positioned inside and outside the coupling for treatment. A mechanism can be provided to rapidly connect and disconnect an ultrasound-activated intravascular wire from an acoustic horn, allowing the wire to be cut in a precisely controlled manner so that the remaining portion of the device can be used as a delivery wire for subsequent procedures. The boss can perform either the connection and / or cutting and / or fragmentation of the wire.

[0064] Custom active wire assemblies may have features arranged at regular intervals along their length to optimize radiopaqueness under high-frequency deflection, which are visible under duplex imaging. Such features may be machined and / or include, for example, gold or platinum marker bands. The length of the occlusion can be estimated during the procedure using both ultrasound and X-rays.

[0065] The distal tip edge of the transverse wire can be rounded and smoothed to limit the possibility of tissue trauma, and can be manufactured from scratch-resistant materials optimized for transverse lesions.

[0066] The custom transverse wire of the present invention has a formable or shaped distal tip for steering and radiopaqueness for visibility, providing more efficient tracking to and through target lesions and facilitating access to side branches.

[0067] Transverse wires are made from elastic, shatterproof materials such as low-density nitinol wires of ASTM Type I to Type IV, and are selected based on different diameters and properties optimized for the target anatomical structure.

[0068] Transverse wires may have lubricating hydrophilic and hydrophobic coatings and / or low-friction jackets to further minimize the adverse effects of fretting and reduce the possibility of solidification.

[0069] The controller can process all measurements of the converted emitted and received waveforms. The user interface can communicate the performance and progress of the device as it advances through any obstruction and provide feedback on the characterization of the lesion's composition and length via visual, auditory, or tactile means such as haptics.

[0070] The system of the present invention can enable data communication between a device and another device or wireless or cloud service for analysis and storage.

[0071] An auxiliary device attached to a luer device through which a wire passes can provide remote measurement related to the movement of the wire through a blood vessel.

[0072] Using automated drives, the speed of wire insertion and withdrawal into the vascular system can be carefully controlled to provide more accurate feedback on plaque composition over the entire length of the lesion. This provides a means to achieve a more precise characterization of the lesion and the intravascular environment.

[0073] Acoustic horns and transducer assemblies may have hollow ports along the entire length of the assembly, with an internal wire connection / disconnection mechanism or locking collet.

[0074] The system of the present invention may include three interconnected components in which the components of the ultrasonic system are distributed. For example, the generator may be separate from the compact unit.

[0075] The wire can be secured within a crimp sleeve. The crimp sleeve captures the wire over its length. The sleeve may be cylindrical or, preferably, have a polygonal cross-section, such as a hexagonal or octagonal pattern that uniformly crimps the wire. The sleeve, or other bonding structures such as a collet, may be made from, for example, stainless steel or aluminum.

[0076] The crimped section can be applied under controlled force, and the thickness of the crimped sleeve wall ensures a uniform load on the wire. Conveniently, the proximal end of the crimped sleeve can be threaded for screwing into the transducer head. Alternatively, the wire may be secured within a crimped set screw that captures the wire at its proximal length.

[0077] structure In a preferred embodiment, the system of the present invention is a) A signal power generator, b) Ultrasonic transducer and, c) Optional acoustic horn, d) A waveguide or transverse wire that transmits high-frequency ultrasonic vibrations from its proximal end to its distal end, capable of cauterizing through an inflexible material blocking an artery, and having dimensions that facilitate standard diagnostic and therapeutic devices, e) A coupling, i.e., a mounting mechanism, that connects the transmission wire to the acoustic horn or directly to the transducer, minimizing losses and enabling faithful transmission of high-frequency mechanical vibrations. f) Means for connecting, disconnecting, or disconnecting a transmission member from an acoustic horn or transducer, with or without using a mounting method, g) A programmable circuit system that includes an integrated or onboard programmable digital signal processing chipset, which processes monitored, transmitted, and received / arriving signals through algorithms that interrogate the response, compare the effect of ultrasonic feedback and resonant frequency standing waves, estimate the size of the opening tunneled into the lesion by the activated tip, and modulate the power of the system via voltage amplitude and system frequency.

[0078] For the purposes of the following explanation, the system can be considered to consist of four main subassemblies and subsystems: 1) A compact housing unit, whether handheld or not, for controlling the operation of a medical device, comprising the following components: a signal generator, an ultrasonic transducer, an acoustic horn (the horn may be part of the transducer assembly or omitted), and an interface coupling component, as well as all or some of the data acquisition, processing, and system control units. Different embodiments of the device system are envisioned. In one embodiment, all components are integrated into a single unit. In another embodiment, the components are distributed, and the generator is housed separately. In yet another embodiment, the transducer horn is separate. In yet another embodiment, the coupling is directly connected to the transducer stack. 2) Coupling and disconnecting modules that allow transverse wires to be connected to ultrasonic transducers and / or horn assemblies. 3) A set of interchangeable flexible transmission member assemblies or transverse guidewires for minimally invasive percutaneous surgical recanalization of blocked or partially blocked anatomical passages. 4) An integrated signal processing circuit board for data acquisition and processing, as well as controlled activation of the system. In some embodiments, this processing board can incorporate analog and / or digital signal analysis and power control of the device, as well as a communication module. This enables wired and wireless connectivity of the device and its data to a wider data network and the internet, and facilitates the development of more intelligent algorithms for managing the system.

[0079] operation Overall, the system operates as follows: a) a signal generator provides electrical energy to a transducer; b) a piezoelectric ultrasonic transducer converts that electrical energy into mechanical vibrations; c) these mechanical vibrations may be further amplified by an acoustic horn; d) a customized transmission member is coupled to the acoustic horn or transducer via a customized coupling method; e) the ultrasonic vibrations are transmitted through the transmission member; f) the distal tip of the transmission member vibrates at a predetermined frequency and amplitude, having the ability to beneficially pulverize affected tissue or other materials; g) digital signal processing and control circuits enable semi-autonomous overall characterization of the lesion, power control, and estimated size of the system's opening.

[0080] When the ultrasonic system is activated, the emitted wave travels along the wire to its distal end, where it is reflected. The reverberations introduced into the wire at different transition points establish a series of secondary and tertiary reflections. These waves are characteristic of different wire designs and features and can be optimized to enhance the differences in the characteristics of their signals. These reflections are determined to consist of specific response patterns of the waveform at any given time for a given input, and their variations are associated with perturbations or differences in the surrounding environment.

[0081] The amplitude of displacement along the wire at a specific frequency changes during the procedure, either during navigation to the lesion site or in contact with affected, inflexible, or calcified tissue within the lesion, as a result of attenuation due to contact with surrounding tissue. Compensation for these losses is performed, for example, by increasing the voltage or current in the generator and transducer. This is used to drive the amplification and / or attenuation of the primary ultrasonic energy. The reverberations within the system are affected in a characteristic way, as are the primary losses, and thus they can be used to characterize the cause and nature of what is causing the traverse and excavation of the lesion, as well as the attenuation.

[0082] control To achieve a constant vibration amplitude, the ultrasonic transducer is controlled by a suitable feedback controller. In the case of ultrasonic waveforms, phase feedback control and comparison can be performed using electrically equivalent models, such as the Butterworth-van Dyke model.

[0083] An ultrasonic transducer can be controlled by the frequency and amplitude of the excitation voltage. In embodiments of the present invention, a method is used in which the change in frequency affects the phase between the voltage and the current. Here, the amplitude of the excitation voltage controls the current and is proportional to the vibration amplitude at resonance. This allows the control algorithm to drive the frequency using only phase and amplitude.

[0084] In a preferred embodiment, the approach is to drive the system using the resonant frequency as the operating point of the control, in combination with an amplitude feedback controller, and to manage this operation using a customized program control algorithm specific to each wire type.

[0085] The advantages of a resonant drive low-damping system are the low voltage requirement and high effective power value. This technique is novel in the context of active guidewire systems. It also offers additional advantages in controlling the response of nitinol wire systems to ultrasonic activation.

[0086] Preferably, the wire is activated at a frequency of 40 kHz for the purpose of advancing into and traversing the lesion. The amplitude of the signal is determined by the degree to which resonance can be found in the system due to perturbations in contact with a lesion or thrombus or any embolic material that is in contact with or forming a complete occlusion in a meandering path. An activation frequency of 40 kHz has been found to be effective in generating a traversing / excavating action in and around the distal end of the wire and assisting in the driving of the wire into and through the lesion.

[0087] The 40kHz activation frequency allows for the transmission of ultrasonic energy over a functional working length of 750mm or less to over 2m, for example, 1.5m, for the activation of the distal tip, which has sufficient intensity to achieve resonance in the harmonic range and sufficient energy to produce not only drilling but also traverse.

[0088] Based on a 40kHz activation frequency also allows for sufficiently compact components to fit into a compact and conveniently shaped handset. For example, using a 20kHz system instead would require the transducer to be larger in both length and diameter, as well as in mass and size.

[0089] Transducers can be designed to have a desired resonant frequency based on their material properties, shape, and prestress. Roughly speaking, the higher the resonant frequency of a transducer, the smaller its size and overall dimensions. For example, a transducer and horn configuration operating at a frequency of 40 kHz can be handheld and compact. This makes it possible to manufacture handheld transducers that can be easily used with wires. Specifically, small transducers can be easily moved along a wire by a single operator and can be easily housed or fixed in specific locations along the wire.

[0090] The concept of such a system is established to lead to atherectomy and remove lesions as obstacles. Therefore, one function of the device being described is to achieve this. However, the product platform proposes another function, namely, to function as a guidewire to deliver treatment or a treatment device to the site of the lesion. The wire traverses lesions of any composition by using ultrasound to convert the guidewire into a temporarily activated wire, allowing the wire to traverse lesions that cannot be traversed without a detour technique.

[0091] Temperature effects and changes in load conditions of nitinol during the process due to interactions with surrounding tissues can lead to changes in resonant frequency and vibration amplitude, which can be compensated for within a certain range for a given transducer.

[0092] Accordingly, in one embodiment of the device, it is disclosed that, in the use of voltage and current, control and analysis via resonant frequencies are used to monitor differential changes over time and length, and this interrogation and compensation are used to characterize the properties of intravascular anatomical structures.

[0093] algorithm The comparison and analysis of primary release response and tertiary feedback response within the wire takes into account characteristic loss variations typical of the engagement of the active component with various healthy and affected tissue types. The analysis distinguishes between intravascular loss and lesion-associated loss, and also differentiates between lesions of different compositions, particularly calcified and non-calcified lesions.

[0094] The resistive loads encountered and recorded by the system change as the active components pass through different anatomical structures. Analog signals are interrogated and conditioned by onboard digital signal processing (DSP), and parametric outputs are processed by algorithms to characterize the response and define feedback and effect controls.

[0095] By utilizing characteristic responses to differential changes occurring in different tunica media and during the passage or navigation of intravascular wires through different anatomical structures, individual algorithms are derived that are used to: 1) determine and compensate for the cause of loss within the system; 2) assess arterial vascular tension; and 3) determine the compositional details of lesions. These algorithms provide automatic level compensation to the wire tip when the wire comes into contact with flexible, inflexible, and calcified materials, amplifying the energy within the system to increase cavitation and neolumbar formation in the latter case.

[0096] The algorithm can be customized to suit the wire type. The range and rate of change, as well as the derivative order of the change, filtered by the signal processing circuit, can be used by the algorithm to characterize the properties of the material through which the wire passes. This can then be communicated to the physician during the procedure to assist in defining the treatment.

[0097] Performance improvement Advantageously, the algorithm can be trained on bench in vitro and in vivo data. The latter is made possible by device embodiments that have a communication mode that provides the transport of data to and from the device. Thus, the quality of the device's operation and interpretation by the device can be improved over time by interpolating more datasets from additional measures built up based on user experience and evidence, which can then be released into the control algorithm for iterative generations of the product.

[0098] These onboard, local, and cloud-based algorithm improvements enhance the device's design and operating interface. This also provides more detailed feedback to physicians using the device, facilitating the customization of device behavior to suit various wire shapes and anatomical structures.

[0099] Combination and Configuration The ultrasound generator, main housing, circuitry, and coupling components remain outside the patient. Most of the transmission member's length and the peripheral catheter components are the only parts of the system that need to enter the patient's body. The proximal portion of the transmission member and the peripheral catheter components remain outside to facilitate coupling to the main unit, as well as the steering and control procedures.

[0100] The first concept of the present invention lies in a detachable active transverse guidewire. In this way, the active transverse wire can function as a guidewire for subsequent treatment after transverse. This involves an operating method that allows the transverse wire to be used in both passive and active configurations. The transverse wire can be connected to or detached from the transducer housing in the field of care.

[0101] In the preferred mode of operation, the intravascular transverse wire can initially be used within the anatomical passage in a passive mode without ultrasonic vibration. While the wire remains within the anatomical passage, the proximal end of the transverse wire can be attached to an acoustic horn / transducer assembly, optionally housed within the housing, to impart energy to the wire acting as a transmission member or to transmit ultrasonic vibrations through the wire. This results in vibration at the distal tip, leading to transverseness of the lesion.

[0102] Following ultrasonic activation, the transverse wire can be disconnected or coupled to the acoustic horn installed within the housing, as needed, returning to a passive wire configuration to facilitate further subsequent devices or treatments.

[0103] The ultrasonic transducer, horn, coupling means, signal generator, power supply, and control circuit can all be housed in a lightweight, compact housing unit that is portable by hand. In another embodiment, the signal generator is separate and coupled to the compact housing unit containing the transducer and horn via a connector cable. In yet another embodiment, the entire system can be designed as a disposable device. In yet another embodiment, the ultrasonic transducer, horn, coupling means, generator, and control circuit can all be housed in the same portable compact housing unit and connected to a power supply via a cable.

[0104] A customized transmission member or wire is disclosed, designed and customized to function as an intravascular transverse guidewire, efficiently transmitting vibrational energy over its length and resulting in controlled ablation at its distal tip.

[0105] Several methods are disclosed for mechanically coupling the transmission member to an acoustic horn or transducer installed within a housing. The coupling configuration can also be used in reverse to function as a coupling-separation configuration.

[0106] Furthermore, as disclosed, the system may include a separate coupling / decoupling component that immediately decouples the transmission member proximal to the rest of the system to facilitate its use as a follow-up guidewire or positioning device.

[0107] The coupling and coupling / discooling mechanisms may be housed either a) within the main housing that houses the transducer and horn, or b) as part of the proximal housing which is part of the transmission member assembly.

[0108] In another embodiment, the transmission member is pre-coupled to an acoustic horn installed within the housing during the manufacturing process.

[0109] The coupling design is optimized to provide efficient transmission and limit undesirable distortion and acoustic transmission loss.

[0110] The coupling method is designed to facilitate user interaction, coupling, and visual / tactile feedback of the coupling state.

[0111] In one embodiment, the transmission member is part of a customized wire assembly having a proximal housing including coupling and coupling-separation arrangements and a wire support, in order to minimize losses in energy delivery through the proximal section of the transmission member. This custom assembly and proximal wire section provide better control and access to the guide wire during passive traverse. The coupling mechanism is designed to be optimized for the transmission of acoustic ultrasonic energy from the transducer and / or acoustic horn. The way the wire is engaged is important to provide the desired transmission of the working force to the distal tip over the length of the waveguide.

[0112] The system can deliver a controlled level of energy to the transmission member via a custom coupling, minimizing losses and inducing initial deformation of the transmission member, thereby minimizing losses and unwanted loads on the transmission member.

[0113] The design of the transmission members or waveguide wires is optimized to control the transmission of wave patterns through different anatomical structures and different materials up to the distal tip. The morphology of the material used is important; at a macroscopic level, the material may exhibit a highly elastic, isotropic material morphology, but it may also have anisotropic micromorphological features that can delay the initiation of starter cracks or inhibit crack propagation.

[0114] This invention envisions a transverse wire custom-built to resonate at the system's driving frequency in order to deliver shattering vibrations to the location of a lesion. This is achieved through knowledge of material properties, including sound velocity and density, in addition to the resonance characteristics and numerical modeling of the thin rod.

[0115] Transverse wires can be manufactured from a single stretched wire, which can be formed by joining sections together end-to-end.

[0116] Proximal features may be included to improve wire coupling to the ultrasonic drive unit and reduce the risk of fatigue failure. Conversely, distal features may be included to improve navigation and transverse performance and increase the opening profile achieved, including wire control and steering optimized for tracking through anatomical structures. Furthermore, marker bands may be included to provide visibility under fluoroscopy or radiography. Radiopaque markers may indicate, for example, the working length and transverse tip of the wire.

[0117] More generally, the present invention allows for the introduction of specific features that are machined into the wire at the proximal and distal ends and along its length to improve the wire's ability to pass through lesions, to strengthen the wire, to allow for better control of the wire, and to enable efficient bonding and energy transfer through the wire. The composition of the design will vary depending on the materials used and the intended use.

[0118] The wire shape and materials used are optimized for different applications. The wire is machined to minimize defects and optimize transmission through tightly controlled taper and keying splines throughout the entire length and sections of the material.

[0119] The material used in the exemplary embodiment is a nickel-titanium (nitinol) alloy. In particular, in the case of the nitinol alloy, the size and occupancy of the inclusions are strictly controlled to limit the possibility of fracture.

[0120] The distal tip design and any geometric features utilize state-of-the-art manufacturing methods and have shapes optimized to enable different effects. Non-limiting examples of these effects include limiting trauma to tissue, accelerating the passage of the waveguide through different anatomical structures, and limiting unwanted lateral deflection through different types of lesions. Lesions may vary in length, diameter, or composition, and may be thrombotic or calcified. The distal tip is also optimized to open a passage or increase its diameter to provide a subsequent therapeutic device, as needed.

[0121] The present invention may include a novel semi-automatic control system capable of controlling or modulating signals from a generator applied to transducers and horns, and thus to transverse wires. Control can be based on feedback from the interaction between the wire and the tissue to control the transmitted signal, adjust for losses due to attenuation or increased resistance, or modulate the applied force.

[0122] Embodiments of the system include visual and haptic feedback indicators that can provide the user with visual, auditory, and / or tactile feedback regarding the state of the device and the nature of the tissue being cauterized. Such feedback may also indicate the level of force that can be applied to cauterize and shred the tissue, as well as to advance the transverse wire.

[0123] The system may include means for providing manual overrides to assist in controlling the amplitude of vibrations delivered to the distal tip. This allows the system to be controlled by the user operating the device during the procedure via a controller and user input mechanism located within the generator and transmission unit, or it may be controlled autonomously.

[0124] The transmission coupling and controller unit may include a sensory feedback system and haptics that allow the user to sense how well the wire is traversing the lesion.

[0125] In the devices described herein, the frequency at which the converter transforms the mechanical signal is a short-range frequency sweep set over a short frequency range to accommodate losses from interactions and collisions due to different forces across the length of the wire. The speed of the microprocessor allows the device to handle small fluctuations in resonance in real time. Signal processing and feedback analysis ensure that optimal mechanical feedback is achieved.

[0126] The device operates at a set frequency of 20kHz to 60kHz, preferably 35kHz to 45kHz, more preferably 37kHz to 43kHz, and most preferably about 40kHz. The device also operates at a desired low power range, for example, 1W to 5W, to reduce the risk of vascular trauma or dissection. For example, in addition to automatic control of the desired low power range of 1W to 5W, the device's output can be controlled to allow the user to amplify the power beyond this range to compensate for unexpected interference and ensure fast and effective traversal. Thus, the device can also deliver maximum load at higher power levels, for example, up to 50W to 100W, to aggressively traverse difficult lesions and overcome tip attenuation or deflection.

[0127] Another objective of the procedure is to use a method to collect data about the traversed lesion, such as its length and composition, which involves interrogating feedback signals to characterize the lesion being traversed by the wire and inform the physician how the target lesion can be treated.

[0128] This data is also provided to the physician as haptic and / or visual or auditory feedback on the display, enabling the physician to operate the device. For example, in one embodiment, this feedback allows the physician to monitor the cross-section and assess the characteristics of the lesion using a simple backlit screen on a compact housing unit.

[0129] In another embodiment, if the user has access to a network, data from the procedure may be captured anonymously to protect patient confidentiality and communicated from the device to a data storage and processing platform where it can be analyzed in real time or later.

[0130] The characteristics of the lesion can also be presented to the user for analysis and interpretation when performing treatment.

[0131] In another embodiment, an attachment is used to record and measure the displacement of a wire as it traverses the vascular system and maps to the lesion composition, thereby characterizing the characteristics of the lesion as a function of displacement through the lesion.

[0132] In another embodiment, the system is cradled within a displacement drive that can push a wire over a controlled distance to provide semi-automated robotic traverse of lesions and more accurate characterization of their composition relative to displacement.

[0133] In another embodiment, the active wire is cradled within the transducer, for example, in a slip-lock mechanism with a lock at its distal end, which allows the wire to move through the center of the transducer body, and from which energy is transmitted.

[0134] In another mechanism, the activation unit can move along the length of the wire via a slip-lock mechanism, be positioned at a desired point, and lock the transmission. [Brief explanation of the drawing]

[0135] To make the present invention easier to understand, the following attached drawings are referenced here as an example. [Figure 1] This is a schematic diagram of the system according to the present invention, including a compact housing unit. [Figure 2] Figure 1 is a perspective view of the system shown. [Figure 3] This is a schematic side view showing another embodiment in which the ultrasonic generator is housed in a separate unit. [Figure 4] This diagram shows the analog and digital data flows within the system. [Figure 5] This flowchart shows the preferred way the system operates. [Figure 6] This diagram shows the system's operational function flow. [Figure 7] This flowchart shows the operation of the semi-autonomous and intelligent control system of the present invention. [Figure 8a] This is a schematic side view of the active wire assembly before connection to the horn, then the active wire assembly connected to the horn using a suitable mechanical coupling method, and the active wire assembly coupled and separated from the main housing and proximal assembly by a coupling and separation method. [Figure 8b]This is a schematic side view of the active wire assembly before connection to the horn, then the active wire assembly connected to the horn using a suitable mechanical coupling method, and the active wire assembly coupled and separated from the main housing and proximal assembly by a coupling and separation method. [Figure 8c] This is a schematic side view of the active wire assembly before connection to the horn, then the active wire assembly connected to the horn using a suitable mechanical coupling method, and the active wire assembly coupled and separated from the main housing and proximal assembly by a coupling and separation method. [Figure 9a] This is a cross-sectional view showing one embodiment of the connection method. [Figure 9b] This is a cross-sectional view showing one embodiment of the connection method. [Figure 9c] This is a cross-sectional view showing one embodiment of the connection method. [Figure 10] This is an enlarged partial cross-sectional view showing another embodiment of a linear push-and-screw connection method. [Figure 11] This is an enlarged partial cross-sectional view showing another embodiment of a linear push-and-screw connection method. [Figure 12] This is an enlarged partial cross-sectional view showing another embodiment of a connection method using mechanical locking. [Figure 13] This is an enlarged partial cross-sectional view showing one embodiment of a screw connection system using a radial release mechanism. [Figure 14] This describes a coupling method that utilizes proximal interlocking features on a transmission member. [Figure 15] This is a perspective view of a wire release mechanism that crushes or cuts the active wire between opposing blades. [Figure 16] This is a schematic diagram of a wire release mechanism that crushes or cuts active wires between blades supported by roller actuating gears. [Figure 17] This is a schematic diagram of a wire release mechanism that crushes or cuts active wires between blades supported by a linear actuation gear. [Figure 18a] This is a schematic detail side view showing a method for crushing active wire. [Figure 18b] This is a schematic detail side view showing a method for crushing active wire. [Figure 18c] This is a schematic detail side view showing a method for crushing active wire. [Figure 19] This is a cross-sectional side view of a proximal subassembly that can measure the displacement when an active wire crosses it. [Figure 20] This is a schematic side view showing a housing unit supported by an automatic drive system. [Figure 21] This is a cross-sectional side view of one embodiment in which an acoustic horn and transducer assembly has an internal wire connection / disconnection mechanism or locking collet and has a hollow port along the entire length of the assembly. [Figure 22] This is a cross-sectional side view of one embodiment in which the acoustic horn / transducer assembly of the activation unit has a hollow port running through most of the body length of the assembly, but a wire exits the assembly through a side port, allowing the activation unit to lock along the wire via a mechanism in the transducer tip. [Figure 23a] This is a schematic side view of an acoustic horn / transducer assembly, illustrating a further method for connecting active wires. [Figure 23b] This is a schematic side view of an acoustic horn / transducer assembly, illustrating a further method for connecting active wires. [Figure 23c] This is a schematic side view of an acoustic horn / transducer assembly, illustrating a further method for connecting active wires. [Figure 24a] These are schematic side views of modified configurations shown in Figures 23a–23c, where the active wire extends along the entire length of the horn / transducer assembly. [Figure 24b]These are schematic side views of modified configurations shown in Figures 23a–23c, where the active wire extends along the entire length of the horn / transducer assembly. [Figure 24c] These are schematic side views of modified configurations shown in Figures 23a–23c, where the active wire extends along the entire length of the horn / transducer assembly. [Figure 25a] This is a schematic side view of a further modification of the arrangement shown in Figures 23a–23c, where the active wire exits the horn / transducer assembly through the side port. [Figure 25b] This is a schematic side view of a further modification of the arrangement shown in Figures 23a–23c, where the active wire exits the horn / transducer assembly through the side port. [Figure 25c] This is a schematic side view of a further modification of the arrangement shown in Figures 23a–23c, where the active wire exits the horn / transducer assembly through the side port. [Figure 25d] This is a schematic perspective view of a further modification of the arrangement shown in Figures 23a–23c, where the active wire exits the horn / transducer assembly through the side port. [Figure 26a] These are schematic side views of a modified configuration shown in Figures 25a–25c, in which the active wire can be detached laterally from the horn / transducer assembly in a direction that crosses the longitudinal axis of the active wire. [Figure 26b] These are schematic side views of a modified configuration shown in Figures 25a–25c, in which the active wire can be detached laterally from the horn / transducer assembly in a direction that crosses the longitudinal axis of the active wire. [Figure 26c] These are schematic side views of a modified configuration shown in Figures 25a–25c, in which the active wire can be detached laterally from the horn / transducer assembly in a direction that crosses the longitudinal axis of the active wire. [Figure 26d]These are schematic detail diagrams of a modified configuration shown in Figures 25a–25c, in which the active wire can be detached laterally from the horn / transducer assembly in a direction that crosses the longitudinal axis of the active wire. [Figure 27a] This is a schematic side view showing housing units positioned at various longitudinal positions along the proximal portion of the active wire protruding from the patient's body. [Figure 27b] This is a schematic side view showing housing units positioned at various longitudinal positions along the proximal portion of the active wire protruding from the patient's body. [Figure 27c] This is a schematic side view showing housing units positioned at various longitudinal positions along the proximal portion of the active wire protruding from the patient's body. [Figure 28] This is an exploded perspective view of various collet configurations for securing the active wire to the horn / transducer assembly. [Figure 29] This is an exploded perspective view of various collet configurations for securing the active wire to the horn / transducer assembly. [Figure 30] This is an exploded perspective view of various collet configurations for securing the active wire to the horn / transducer assembly. [Figure 31] This is an exploded perspective view of various collet configurations for securing the active wire to the horn / transducer assembly. [Figure 32a] Figure 30 is an enlarged perspective view of the collet shown. [Figure 32b] Figure 30 is an enlarged perspective view of the collet shown. [Figure 33] This is a schematic cross-sectional side view of a further collet arrangement. [Figure 34a] This is a schematic side view of a further active wire of the present invention. [Figure 34b] This is a schematic side view of a further active wire of the present invention. [Figure 35] This is a schematic side view of the active wire of the present invention. [Figure 36] This is a perspective view of a modified example of the present invention, in which the active wire has an angularly offset distal end portion. [Figure 37] Figure 35 is a schematic side view of an active wire having an angularly offset distal end portion. [Figure 38a] This is a schematic side view of a further active wire of the present invention, including a marker band. [Figure 38b] This is a schematic side view of a further active wire of the present invention, including a marker band. [Figure 39] This is a schematic side view of another active wire of the present invention. [Figure 40] This is a schematic side view of another active wire of the present invention, each having an enlarged spherical distal tip. [Figure 41] This is a schematic side view of another active wire of the present invention, each having an enlarged spherical distal tip. [Figure 42a] This is a schematic side view showing that the wire of the present invention is used first as an active wire for traversing a lesion, and then as a guide wire for transporting a subsequent device to the lesion. [Figure 42b] This is a schematic side view showing that the wire of the present invention is used first as an active wire for traversing a lesion, and then as a guide wire for transporting a subsequent device to the lesion. [Figure 42c] This is a schematic side view showing that the wire of the present invention is used first as an active wire for traversing a lesion, and then as a guide wire for transporting a subsequent device to the lesion. [Modes for carrying out the invention]

[0136] Figure 1 includes a schematic diagram of a compact housing unit 2. In this configuration, the compact housing unit 2 includes an ultrasonic generator 4, an ultrasonic transducer 6, and an acoustic horn 8. The housing unit 2 is connected to an available power supply via a power cable 10.

[0137] Figure 1 also shows an active transverse wire assembly 12 that can be connected to the housing unit 2. The active wire assembly 12 includes flexible transmission members in the form of wires 14.

[0138] The proximal section of the active transverse wire assembly 12 includes a mounting module 16 and a coupling / disconnecting module 18, providing one or more additional ports 20. The distal section of the active transverse wire assembly 12 is also shown, including an enlarged view 22 of the distal tip 24 of the wire 14. In this example, the distal tip 24 is spherical.

[0139] When coupled and activated, the transducer 6 and wire 14 vibrate with sufficient amplitude at the proximal end so that the distal end of the wire 14 can cause the lesion to be crossed by the energy transmitted along the wire 14.

[0140] The wire 14 may be, for example, longer than 2 meters. For example, access to a lesion in or through the foot may involve the wire 14 traveling a distance of typically 1200 mm to 2000 mm within the vascular system, depending on whether an ipsilateral or contralateral approach is chosen. In this regard, the wire 14, which tapers distally to become a thin wire at its tip, can navigate into the foot arteries and around the arch of the foot between the dorsal and plantar arteries. However, the present invention is not limited to foot or other peripheral applications and can also be used in coronary artery applications, for example, where the ability of the wire 14 to navigate and excavate in tortuous, small-diameter arteries is also beneficial.

[0141] Figure 2 also shows a compact housing unit 2 and an active transverse wire assembly 12. It also shows a user input control unit 26 and means for providing user feedback, exemplified here by a display 28.

[0142] The wire 14 may be coupled to the transducer 6 via the acoustic horn 8, or it may be coupled directly to the transducer 6, in which case the acoustic horn 8 may be omitted. For example, referring to Figure 2, the mounting module 16 may directly attach the wire 14 to the transducer 6 inside the body of the housing unit 2, below the display 28 of the housing unit 2.

[0143] Figure 3 shows a modified configuration in which the ultrasonic transducer 6 and acoustic horn 8 are integrated within a compact housing unit 2, while the ultrasonic generator and circuitry 4 are housed in a separate generator housing unit 30. In this case, the housing unit is connected to the generator housing unit via a connector cable 32.

[0144] Figure 4 shows the system's components and elements, as well as the data flow through the system, including communications. A controller within the housing unit controls the ultrasonic generator to produce a signal that is converted into ultrasonic energy by a transducer. The ultrasonic energy is supplied via an optional acoustic horn to an active wire that navigates the vascular system and crosses obstructions such as chronic total occlusion (CTO).

[0145] Feedback from the active wire is received by a feedback receiver, amplified by an amplifier, filtered by a series of bandpass filters, and then passes through an analog-to-digital conversion to generate feedback data that is sent to the processor. The controller receives data from the processor and communicates that data from the housing unit to local storage and / or the cloud, preferably wirelessly, using, for example, a Wi-Fi network or Bluetooth connection. Figure 4 also shows means of providing feedback to the user within the housing unit, such as the aforementioned display and / or haptic feedback system.

[0146] Next, Figure 5 shows that the system can be used in passive or active mode. First, the active wire assembly is introduced into the artery, and the distal tip of the wire is navigated to a target obstruction that may be calcified or diffuse. If the obstruction can be crossed without ultrasonic activation of the wire, the system remains in passive mode and the obstruction is crossed. Conversely, if the obstruction cannot be crossed without ultrasonic activation of the wire, the active wire assembly is connected to the housing unit and then activated with ultrasound to bring about the crossing.

[0147] When an obstruction is traversed, the active wire assembly is detached from the housing unit. The wire is now ready to function as a guide wire, facilitating the introduction and navigation of subsequent treatment or diagnostic devices as needed.

[0148] Figure 6 further summarizes the system's operation and actions, as well as the decision points associated with its use.

[0149] Figure 7 is a flowchart summarizing the semi-autonomous control of the system. In practice, the system can collect user-inputted data before operation, such as the expected type of lesion and its anatomical location. This data can be combined with real-time inputs, such as power requirements, as the active wire traverses the lesion.

[0150] The system can automatically sense changes in frequency and power and optimize the performance of the active wire using an onboard algorithm. This information can be fed back to the user through haptic, visual, or auditory means, such as a display on the housing unit.

[0151] The variation in the magnitude of the input and control parameters of current, voltage, and frequency due to the characteristic capacitance of the converter provides a matrix of measurements and controls used to determine the required power and characterize the lesion being traversed.

[0152] Because the input is kept constant, fluctuations in current represent absorbed strain energy or attenuation effects along the wire, particularly along its distal tip, as it traverses the lesion at the system's maintained frequency.

[0153] By monitoring the current, the behavior of the wire can be interpreted, and by modulating the voltage, it becomes possible to amplify the power and recover the frequency as the wire acts on the contact surface to reduce the offset. This series of measurements over a narrow frequency range allows for the overall characterization of the lesion's composition, whether it is calcified, fibrous, or gelatinous along its entire length.

[0154] These interpolated characteristic components, while not absolute characteristics of the lesion, indicate its composition and consistency, such as calcific, hard, compressed, or dispersed, or compressed calcific particles versus uncompressed fibrous material versus hard or soft gelatinous material. These characteristics indicate the nature and severity of the lesion and can inform clinicians of the optimal treatment to consider.

[0155] The system can also transmit this data via existing wireless or wired communication networks and receive algorithms for optimized performance.

[0156] Figures 8a to 8c show the mounting method, where the active transverse wire assembly 12 and the compact housing unit 2 are not mechanically coupled together. In this configuration, as shown in Figure 8a, wire 14 can be used as a conventional guidewire in its passive mode, i.e., without ultrasonic activation.

[0157] Figure 8b shows how the active transverse wire assembly 12 can be mechanically coupled to the housing unit 2 as needed. Specifically, the engagement of the mounting module 16 with the distal end of the housing unit 2 results in the alignment and mechanical coupling of the proximal end portion of the wire 14 in the central bore 34 at the distal end of the acoustic horn 8. Once coupled in this manner, ultrasonic vibrations can be transmitted from the acoustic horn 8 along the wire 14 to transverse the lesion.

[0158] After traversing the lesion, Figure 8c shows the wire 14 coupled and separated from the acoustic horn 8 following the operation of the coupling / separation module 18. Specifically, the opposing blades of the coupling / separation module 18 are brought around the wire 14 to break or cut it. The compact housing unit 2 and the proximal section of the active transverse wire assembly 12 can be detached from the wire 14, and thus all other components can be separated from the wire 14.

[0159] Figures 9a–9c show one embodiment of the proximal section of the active transverse wire assembly 12, particularly the mounting module 16. In this embodiment, the wire 14 is mechanically joined to a threaded connector 38 (36) which includes an enlarged head and a male thread extending in the proximal direction. The head of the threaded connector 38 is gripped and engaged by a periphery sleeve 40 having a longitudinally stepped shape. The thinner tubular distal end of the sleeve 40 provides strain relief around the wire 14.

[0160] The sleeve 40 and the head of the screw connector 38 are constrained to rotate together around the central longitudinal axis of the wire 14. For example, the cross-sectional view in Figure 9c shows that the head of the screw connector 38 may have various rotationally asymmetric external shapes 42 that complement and interlock with the corresponding internal shape of the sleeve 40. However, relative axial movement is possible between the sleeve 40 and the head of the screw connector 38.

[0161] The acoustic horn 8 is shown inside the housing unit 2. The acoustic horn 8 includes a central distal threaded bore 44 that is opposite and complements the male thread of the screw connector 38.

[0162] When coupled as shown in Figure 9b, the proximal section of the active transverse wire assembly 12 is axially pushed into the housing unit 2 via click connectors 46, 48. The click connector 46 of the housing unit 2 is integrated with an axially retractable tube 50 which is biased distally by a spring 52. By retracting the tube 50 against the bias of the spring 52, the male thread of the screw connector 38 can be screwed into the bore 44 of the acoustic horn 8 by rotating the sleeve 40 which applies torque to the head of the screw connector 38. When the thread of the screw connector 38 is fully engaged with the bore 44 of the acoustic horn 8, the sleeve 40 is released, and the spring 52 acting on the tube 50 pushes the proximal section of the active wire assembly 12, including the sleeve 40, away from the wire 14 and the acoustic horn 8.

[0163] Figure 10 shows another embodiment of a screw connector in which a spring mechanism 54 is installed in the proximal section of the active wire assembly 12. The screw connector 38 and wire 14 are shown as previously described. The active transverse wire assembly 12 and the housing unit 2 are coupled via a snap-fit ​​component 56. Figure 11 shows a variation of the arrangement in Figure 10, further including a distally extending snap-fit ​​section 58.

[0164] Figure 12 shows a screw connector 38 including a manual push-screw-pull slotted entry and locking system 60, which is best understood in the perspective detail view of the distal end of the housing unit 2. The proximal section of the active transverse wire assembly 12 includes an inward-facing lug 62 that is initially aligned with an external slot 64 formed at the distal end of the housing unit 2. After the lug 62 moves proximal along the slot 64, the proximal section of the active transverse wire assembly 12 is rotated around the central longitudinal axis of the wire 14. This causes the lug 62 to align with a notch 66 formed at the distal end of the housing unit. As shown in the cross-sectional view of Figure 12, the lug 62 engages distally with the notch 66, locking the proximal section of the active transverse wire assembly 12 to the distal end of the housing unit 2.

[0165] Figure 13 shows the grip-and-release mechanism 68 of the radial connector. The screw connector 38 is held by a radial retainer 70, which is initially held in a radially inward position by a sleeve 72 that is axially movable. The retainer 70 transmits torque from the sleeve 72 to the screw connector 38, screwing the male thread of the screw connector 38 into the bore 44 of the acoustic horn 8. Once the screw connector 38 is fully engaged with the acoustic horn 8, the sleeve 72 slides proximal on the distal section of the housing unit 2, releasing the radial retainer 70 and causing it to spring radially away from the screw connector 38. This causes the wire 14 to be coupled and separated from the sleeve 72 and from the rest of the proximal section of the active wire assembly 12.

[0166] Figure 14 shows a connection arrangement in which the proximal end of the wire 14 is embedded within a coupling connector 76 and has a series of geometric features, such as a circumferential ridge 74 that interlocks with the coupling connector 76. The coupling connector 76 has a male thread at its proximal end that engages with the threaded bore 44 at the distal end of the acoustic horn 8.

[0167] Next, looking at Figures 15 to 17, these diagrams show various convenient arrangements for breaking the wire 14 and releasing it from the housing unit 2 after successfully traversing the lesion.

[0168] Figure 15 shows the internal mechanism of the squeeze-action wire breaking system 76. For clarity, the surrounding housing has been omitted. Here, the wire 14 supports a pair of sharp blades 78 facing each other around the wire 14. The blades 78 are integrated with an elastic lever 80 that, when squeezed together, separates the wire 14 between the blades 78.

[0169] Figures 16 and 17 show blades 82 attached to their respective meshing gears 84, with one gear on each side of the wire 14. Opposite rotation of the gears 84 brings the blades 82 together, gripping and cutting the wire 14. In Figure 16, the gears 84 are rotated by the user rotating at least one exposed side of the gears 84, which in turn rotates the other gear. Conversely, in Figure 17, when the linear push-button mechanism 86 is pressed, one gear is rotated, which in turn rotates the other gear.

[0170] Figures 18a–18c illustrate another approach to breaking the wire, which involves applying a periodic load that introduces a sharpness defect and causes fatigue.

[0171] Figure 18a shows the wire 14 in its original shape with a smooth outer surface, as it is used to traverse a lesion. Figure 18b shows the wire 14 after it has traversed the lesion, with notches or grooves 88 made, for example, by a blade. When then vibrated by a transducer with sufficient energy at the appropriate frequency, the wire 14 immediately fractures, as shown in Figure 18c. This is because the crack 90 propagates across the diameter of the wire 14 from the transverse notches or grooves 88, which act as points of weakness or stress concentration for initiating the crack 90.

[0172] This fracture mechanism tends to be used to separate crimped nitinol wires by utilizing ultrasonic energy and the inherent toughness of nitinol. Making notches on the surface of wire 14 creates scratch defects where stress concentrates. Because the critical crack length of nitinol is relatively short, high-amplitude ultrasonic loading causes wire 14 to break there by resulting in a completely planar strain surface fracture.

[0173] Figure 19 shows a measuring attachment 92 that can measure and display the distance traveled longitudinally by the wire 14 and proximal sheath 94 relative to the housing 96 and foresheath 98. In this example, a linear graduated scale is etched, printed, or molded onto the proximal sheath 94. Such an attachment 92 allows for convenient measurement of the distance traveled by the distal end of the wire 14 within the vascular system at the proximal end of the wire 14.

[0174] Figure 20 shows a linear drive system 100 that can cradle or otherwise hold the housing unit 2 and can move the housing unit 2 forward and backward in the longitudinal direction as shown. For this purpose, the drive system 100 includes a drive mount 102 and a unit 104 which includes a motor, encoder, and force sensor unit. The drive system 100 facilitates the autonomous or robotic insertion and navigation of a wire 14 that traverses a lesion through the vascular system.

[0175] Figure 21 shows an active wire 14 passing through a threaded ultrasonic transducer and horn assembly 106. A locking collet 108 has a tapped portion that screws into the threads to close a spring collet clamp 110. The spring collet clamp 110 clamps the wire 14 over a long interface. This configuration allows the proximal end of the wire 14 to be supplied through the acoustic horn / transducer assembly 106 and connected to the assembly 106 at any of several points along the length of the wire 14.

[0176] Figure 22 shows a modification of the arrangement in Figure 21, in which the acoustic horn / transducer assembly 106 has a hollow port that runs through most, though not all, of the body length of the assembly 106. In this case, the wire 14 exits through the side port 112, allowing this activation unit to lock at any of several points along the wire 14 via a mechanism in the distal tip of the assembly 106.

[0177] Figures 23a and 23c show the arrangement in which the proximal end of the wire 14 is received in the central distal bore 114 of the acoustic horn 8 within the housing 2. After inserting the wire 14 into the bore 114 as shown in Figure 23a, the twist-lock mechanism 116 at the distal end of the housing 2 is rotated to lock the wire 14 into the acoustic horn 8 as shown in Figure 23b. The acoustic horn 8 can then supply ultrasonic energy into the wire 14 as shown. When ultrasonic activation of the wire 14 is no longer needed, the wire 14 can be unlocked from the acoustic horn 8 by reversing the twist-lock mechanism 116, and then pulled out longitudinally as shown in Figure 23c.

[0178] Figures 24a–26d illustrate various additional concepts related to the activation of adjustable locations. They show further arrangements in which the activation system, including a housing 118 containing a transducer / horn 120, can slide and lock, or "slip and stick," on the transverse wire 14, and thus be able to connect to the transverse wire 14 at any location along the proximal section of the wire 14 outside the patient's body.

[0179] For this purpose, Figures 24a–24c show a modification of the arrangement shown in Figures 23a–23c, in which the central bore 114 of the transducer / horn 120 extends longitudinally through the housing 118 and opens at both the distal and proximal ends of the housing 118. This allows the wire 14 to extend through both ends of the housing 118 and protrude from there, as shown in Figure 24b, thereby allowing the housing 118 to be repositioned longitudinally with respect to the wire 14.

[0180] In this configuration, the wire 14 is still inserted longitudinally into the distal end of the transducer / horn 120, as shown in Figure 23a, and is pulled longitudinally out from the distal end of the transducer / horn 120, as shown in Figure 23c. Again, the wire 14 is locked to the transducer / horn 120 by rotating the twist lock mechanism 116 at the distal end of the housing 118, as shown in Figure 23b.

[0181] Figures 25a to 25d show that the wire 14 can exit the housing 118 through openings other than the central opening 122 at the proximal end of the housing 118. In the example shown here, the wire 14 exits the transducer / horn 120 through a lateral port 124 that communicates with the central distal opening of the bore 34. The laterally exiting portion 126 of the wire extends from the port 124 and exits the housing 118 through a lateral opening aligned with the port 124. Thus, the wire 14 exits the transducer / horn 120 laterally, deflected at an acute angle from the central longitudinal axis of the transducer / horn 120.

[0182] As described above, the wire 14 is inserted longitudinally into the distal end of the transducer / horn 120, as shown in Figure 23a, and pulled longitudinally out from the distal end of the transducer / horn 120, as shown in Figure 23c. In this case as well, the wire 14 is locked to the transducer / horn 120 by rotating the twist lock mechanism 116 at the distal end of the housing 118, as shown in Figure 23b.

[0183] In a further modification of the lateral exit principle shown in Figures 25a–25c, Figures 26a–26d show an arrangement in which a wire 14 can be pulled laterally from (and optionally inserted laterally into) the transducer / horn 120 within the housing 118. The wire 14 is received in a longitudinal slot 130, which can be opened and closed by rotating a swivel jaw 128 of the acoustic horn 118, as shown in the detailed view of Figure 26d. When closed, the jaw 128 surrounds and engages the wire 14, coupling the wire 14 to the transducer / horn 120. When opened by relative angular motion around the central longitudinal axis, the jaw 128 releases the wire 14 from the transducer / horn 120, allowing it to exit the transducer / horn 120 through the slot 130. The housing 118 has a corresponding slot 132 that allows the wire to exit laterally from the housing 118 and release the wire 14.

[0184] Since the excitation of the wire 14 is required only distal to the housing 118, in the embodiments shown in Figures 24a to 26d, damping material within the housing 118 can prevent or dampen the excitation of the portion of the wire 14 extending proximal to the housing 118. Various materials, usually elastomers, such as silicone seals and gaskets, can be used to provide damping. More generally, unwanted excitation can be damped by contact between the wire 14 and the wall of the housing 118 around the side port of the housing 118.

[0185] Figures 27a–27c show that a physician can cut and reconnect the housing 118 at any point along the proximal portion of the wire 14, allowing the wire 14 to be loaded and unloaded as needed. As shown in Figure 27c, the wire 14 may be marked along its length at regular or irregular intervals 133, such as λ / 2 and λ / 4, which are characteristic of harmonics at an activation frequency of, for example, 40 kHz.

[0186] The housing 118 can be detached from the wire 14 multiple times as the wire 14 is supplied forward, i.e., distally, and then reattached to the wire 14 at specific longitudinal intervals. Generally, the housing 118 or the wire 14 can move relative to each other, allowing the physician to move the wire 14 across a lesion or find a better position for the housing 118 to activate the wire 14. By detaching the housing 118 from the wire 14 and later reattaching it to the wire 14, it becomes possible to position or leave other devices on the wire 14 and not move the wire 14 during the course of the procedure, thereby improving ease of use for the physician.

[0187] For example, the housing 118 can be attached to the wire 14 near where the wire 14 enters the introducer sheath 135 and the patient's body 137, as shown in Figure 27a. Figures 27b and 27c show other locations where the housing 118 can be attached to the wire 14. Figure 27b shows a housing located midway between the introducer sheath 135 and the proximal end of the wire 14, and Figure 27c shows a housing 118 located at or adjacent to the proximal end of the wire 14.

[0188] Next, looking at Figures 28 to 33, these figures illustrate various connector concepts whose primary objective is to achieve excellent acoustic coupling between the transverse wire and the rest of the system. In this regard, the transducer and the coupling method must function in sync. Specifically, the transducer is designed to resonate at the system's driving frequency, and optionally includes a coupling interface component, such as an acoustic horn.

[0189] The transducer may be made, for example, from a Grade 5 titanium or aluminum alloy or steel alloy in a stepped configuration. The shape and dimensions of the transducer are selected to achieve amplification gain while ensuring that the system remains close to its operating resonant frequency. Furthermore, any modifications to the distal drive surface of the transducer to accommodate the connector must be considered and described in relation to the resonant response.

[0190] Figure 28 shows a transducer 134 fitted with a double-tapered collet 136 and a retaining screw 138. The retaining screw 138 has external components to facilitate gripping and rotation by the user.

[0191] The wire 14 enters through the central hole 140 of the set screw 138 on the distal side of the transducer 134, opposite the countersunk base hole 142. The wire 14 extends through a collet 136 inserted between the base hole 142 and the set screw 138. The taper at the proximal end of the collet 136 complements the countersunk base hole 142. The set screw 138 similarly receives and complements the taper at the distal end of the collet 136.

[0192] The collet 136 includes a first pair of slits 144 at its proximal end and a second pair of slits 146 at its distal end. Each pair of slits 144, 146 extends longitudinally beyond half the length of the collet 136. Each pair of slits 144, 146 lies in mutually orthogonal planes intersecting along the central longitudinal axis of the collet 136. The second pair of slits 146 is rotated 45° about the central longitudinal axis relative to the first pair of slits 144.

[0193] The torque applied to the set screw 138 advances the set screw 138, compressing the collet 136 longitudinally. As a result, the tapered end compresses the collet 136 radially, and the slits 144, 146 also allow the collet 136 to compress radially and grip the wire 14. Advantageously, the collet 136 provides a substantially uniform load pattern based on a uniform radial reduction, thus providing a uniform grip on the wire 14, improving energy transfer and fatigue life.

[0194] Figure 29 shows a transducer 148 fitted with a single-taper male threaded collet 150. The tapered proximal end of the collet 150 has an orthogonal slit 152, similar to the collet 136 in Figure 28. When torque is applied to the collet 150, causing it to advance along the complementary threaded bore 154 at the distal end of the transducer 148, the collet 150 anchors the wire 14 within the threaded bore 154. The complementary taper at the proximal base of the bore 154 then compresses the collet 150 radially, gripping the wire 14.

[0195] Figure 30 shows a modified version of the arrangement shown in Figure 29, in which the wire 14 extends from its distal end along the entire length of the transducer 148 and exits from its proximal end.

[0196] Figures 31, 32a, and 32b show a transducer 156 having a double-tapered counter-locking wire-release collet 158. The counter-locking system embodies the concepts of mutual alignment and misalignment between a pair of longitudinally divided collet portions 160, 162 that can rotate relative to each other around a common central longitudinal axis. When the longitudinal slots 164 of the collet portions 160, 162 become misaligned, as shown in Figure 32a, the wire 14 is trapped within the collet 158. Conversely, when the longitudinal slots 164 of the collet portions 160 and 162 are aligned as shown in Figure 32b, the wire 14 is released from the collet 158 ​​and can exit the collet 158 ​​in a direction that crosses the central longitudinal axis of the collet 158.

[0197] Accordingly, the retaining screw 166 and transducer 156 include a slot 168 that can be aligned to release the wire 14 for lateral removal or lateral insertion from the transducer 156, in the manner of the embodiment shown in Figure 26c.

[0198] The principle here is that the wire 14 can be released from the collet 158 ​​when the clamping torque force is released and the slots 164 of parts 160 and 162 of the collet 158 ​​align with each other and with the slots 168 of the retaining screw 166 and transducer 156. This is achieved by securing the proximal part 162 of the collet 158 ​​to the transducer 156 and applying torque from the retaining screw 166 to the distal part 160 of the collet 158 ​​when the retaining screw 166 rotates and releases the clamping force.

[0199] The proximal portion 162 of the collet 158 ​​can be, for example, mounted on a spline component of the transducer 156 to align the transducer 156 and lock it in place to prevent rotation. The distal portion 160 of the collet 158 ​​may have facets that, in conjunction with the retaining screw 166, allow the distal portion 160 to rotate relative to the proximal portion 162 to the extent necessary to release the wire 14.

[0200] The collets shown in these embodiments may include an internal countertaper to optimize the land length over which the wire 14 is gripped. This advantageously limits the point load on the wire 14 and the resulting microstructural damage that could otherwise facilitate the formation of microstructural defects.

[0201] Figure 33 shows the internal extension collet 168 housed in the head of the transducer 170. In this embodiment, the collet 168 is integrated within the transducer 170 and is therefore integral to the device itself. The wire 14 extends along the entire length of the collet 168 and protrudes distally and proximal to the transducer 170.

[0202] The transducer 170 shown in Figure 33 has a tubular body 172 surrounding a collet 168. The collet 168 has an enlarged distal head 174 that protrudes from the distal end of the body 172 and has a diameter larger than the inner diameter of the body 172. The inclined ramp surface 176 on the proximal side of the head 174 is in contact with and supports the distal end of the body 172.

[0203] A torque screw 178 is positioned at the proximal end of the main body 172. An annular backing nut 180 and a piezo stack 182 are sandwiched between the torque screw 178 and the main body 172.

[0204] The collet 168 has a threaded proximal portion that is screwed to the torque screw 178. Thus, the torque screw 178 couples the collet 168, and therefore the wire 14, to the transducer 170, thereby transmitting ultrasonic energy from the transducer 170 to the wire 14. Furthermore, as the torque screw 178 is rotated, the collet 168 is retracted proximal to the body of the transducer 170. As the collet 168 moves proximal to the body 172, the inclined ramp surface 176 of the enlarged distal head 174 contacts and supports the distal end of the body 172, causing the collet 168 to radially clamp to the wire 14.

[0205] Figures 34a and 34b show a wire 14 having a substantially straight proximal section 184, a tapered intermediate section 186 distally, and a substantially straight distal excavation section 188 for traversing the lesion. Due to the taper of the intermediate section 186 between them, the distal section 188 has a smaller diameter than the proximal section 184. For example, the proximal section 184 may have a diameter of 0.43 mm and the distal section 188 may have a diameter of 0.25 mm. Since the intermediate section 186 can extend to a length of more than 1 meter, the taper between the proximal section 184 and the distal section 188 is very slight and therefore greatly exaggerated in these drawings.

[0206] The overall shape of the wire, including its nominal diameter and length, is determined by the sound velocity inherent to the wire's material. This property is determined for the material selected for the transducer and the wire. The dimensions of the straight and tapered sections of the wire are machined to functional wavelength intervals.

[0207] If nitinol material is selected, in this example, λ, λ / 2, and λ / 4 are determined to be 168 mm, 84 mm, and 42 mm, respectively. The selected frequency generates harmonics along the length of the wire, and the load at the end of the wire helps establish standing waves for featureless lesions.

[0208] The distal section 188 can be tapered along its length or have a uniform diameter, and the harmonics can be λ or at least λ / 4. The system can generate harmonics over a certain range.

[0209] Since the purpose of the activated wire 14 is to excavate the lesion, its dimensions are optimized to excavate the largest possible volume with a given waveform. In this regard, Figure 34b shows that when activated, the distal section 188 of the wire 14 moves in a primary longitudinal mode, moving inward and outward, and also moves radially, mapping out through the longitudinal movement of the wire 14 to excavate a larger volume at the distal end. The distal section 188 of the wire 14 is also seen to move in other modes, via transverse and undulating motion under the resonant wave and the second-order mode of the differential harmonic, depending on the activation frequency and the length of the distal section 188.

[0210] Figure 35 illustrates how wire 14 can be manufactured from sections welded together end-to-end. In this embodiment, the proximal section 184 is machined to a standard diameter to provide amplification and a standard connection for a proximal-loaded activation device. The proximal section 184 acts as a shaft that can be welded to one of a selection of wires of different diameters, which can have a custom distal end and tip, at a joint 190 circled in Figure 35. This beneficially reduces the need to maintain stocks of different wire diameters, as several sections of different wire diameters can be assembled to produce wires of many required configurations. Because the welded joint 190 of wire 14 is in a low-stress location, the load applied to the joint 190 during the activation process will not cause catastrophic fatigue failure.

[0211] Moving on to Figures 36 and 37, these drawings show a wire 14 formed or shaped to have an angularly offset distal drilling section for traversing a lesion. In this embodiment, the distal section is not straight but is angled by a heat-set tip 192. The dimensions of the tip 192 are optimized to provide improved performance with respect to steering to and drilling the lesion. Specifically, the angle of the tip 192 with respect to the longitudinal axis of the distal section and the length of the tip 192 determine the ability of the wire 14 to steer into a particular collateral artery. The angle and length of the tip 192 also affect how the wire 14 drills through a portion of the stenotic material once activated.

[0212] If the dimensions of the tip 192 are characteristic of the harmonics, for example, if it is λ / 8 or about 22 mm in length, the wire 14 will open a tunnel in the lesion that is considerably larger than, for example, a 25 mm tip section. The amplitude of the waveform and the number of times the distal section of the wire 14 passes through the calcified section determine the diameter of the tunnel being excavated.

[0213] If the angle of the tip 192 is too large, the lever arm will become larger, potentially causing excessive fatigue of the wire 14. Conversely, if the angle of the tip 192 is too small, the wire 14 may not be able to be effectively steered. In this regard, Figure 37 shows that the tip 192 can be offset by approximately 15° to 45° from the longitudinal axis of the wire 14, allowing the tip 192 to crush and excavate larger volumes of lesions. The tip 192 is appropriately heat-treated, for example, at a temperature above 500°C for less than 10 minutes, to ensure a microstructure that is resistant to crack propagation and therefore fatigue.

[0214] Figures 38a and 38b illustrate how the visibility of the wire 14's location within the patient's body can be improved, for example, by using a gold marker band 194. Such a marker band 194 may be fixed, for example, near the distal end 196 of the wire 14 (e.g., about 3 mm from the distal end 196), and also from the distal end of the proximal section 184, just before the start of the tapered intermediate section 186. The marker band 194 is positioned at the location of the minimum load when using the wire 14. This minimizes the possibility of the marker band 194 becoming detached or the wire 14 failing at those locations. The marker band 194 tends to flush fit into the polished circumferential groove around the wire 14.

[0215] Figure 39 shows a modified example in which the distal tip 196 of the wire 14 is rounded and there is no sharp transition. For example, in this example the proximal section 184 may be 1800 mm long, the tapered intermediate section 186 may be 84 mm long, and the distal section 188 may be 10 mm long. In this case as well, the marker band 194 surrounds the distal tip 196 of the wire 14 and the wire 14 near the distal end of the proximal section 184.

[0216] Figures 40 and 41 show other modifications of the wire 14, each having a rounded, spherical distal tip 198 to avoid a sharp transition. The spherical tip 198 may, for example, be 3 mm to 4 mm in length and have a diameter slightly greater than 0.4 mm.

[0217] Except for its spherical tip 198, the wire shown in Figure 40 is otherwise similar to the wire 14 shown in Figure 39.

[0218] In this case as well, the wire 14 shown in Figures 40 and 41 has a circumferential marker band 194 that can be flush-fitted into a circumferential groove polished around the wire 14. Conveniently, as shown, the spherical tip 198 can be surrounded by one of the marker bands 194.

[0219] In the example shown in Figure 41, the wire has a proximal section that includes a straight section 200 and a distally tapered section 202. The straight section 200 may have a textured surface, as shown, to improve engagement with the activation device. The proximal section is welded to the intermediate section, which makes up the majority of the length of the wire 14. The intermediate section also includes a straight section 204 and a short distally tapered section 206. A marker band 194 is shown surrounding the straight section 204 near the distally tapered section 206 of the intermediate section 194. Finally, a short, slender distal section 208 extends distally from the intermediate section 186 to a spherical tip 198.

[0220] Finally, looking at Figures 42a to 42c, these schematic diagrams show how wire 14 can be used first as an active wire to traverse the lesion 210, and then as a guide wire to transport the subsequent diagnostic or therapeutic device 214 to the lesion 210.

[0221] In Figure 42a, wire 14 is shown to extend distally into the patient's body 137 through an introducer sheath 135. The distal end of wire 14 is navigated through the patient's vascular system 212 to reach a lesion 210. Wire 14 is shown here to be activated by an activation unit 2, and thus to excavate and traverse the lesion 210 by vibration of its distal end.

[0222] In this example, the activation unit 2 is shown at the proximal end of the wire 14. However, the activation unit 2 can instead be positioned at one of several intermediate positions along the proximal portion of the wire 14 protruding from the patient's body 137.

[0223] As shown in FIG. 42b, when the lesion 210 is successfully traversed, the wire 14 is deactivated and left in place within the patient's vasculature 212. Next, the activation unit 2 is removed from the wire 14, exposing the proximal end of the wire 14.

[0224] The deactivated wire 14 can now function as a guide wire for transporting a subsequent diagnostic or treatment device 214 to the lesion 210, as shown in FIG. 42c. The device 214 can most conveniently be inserted into the proximal end of the wire 14. However, in principle, the device 214 can instead be attached to the wire 14 at any location along the proximal portion of the wire 14 that remains outside the patient's body 137.

[0225] (Summary of this embodiment) A summary of the embodiments described above is set forth below.

[0226] (First device) An intravascular device for traversing an obstacle within a blood vessel, the device comprising: An elongated intravascular wire; and During use, a coupling for transmitting ultrasonic energy from an ultrasonic energy source along the wire to an active tip at the distal end of the wire, the coupling being arranged to couple the source to the wire at any of a plurality of individual operating positions along the length of the wire for the transmission of ultrasonic energy to the active tip. An intravascular device, wherein the coupling is arranged to allow relative longitudinal movement between the source and the wire when moving between the operating positions.

[0227] In the first device, the coupling can be arranged to allow relative longitudinal movement between the source and the wire while remaining attached to the wire.

[0228] In the first device, the coupling can be arranged to allow relative longitudinal movement between the source and the wire while remaining attached to the wire.

[0229] In the first device, the coupling may be arranged to allow the relative longitudinal movement by being removed from and reattached to the wire.

[0230] In the first device, the coupling and / or the source may include a distal opening and a proximal or lateral opening for longitudinal insertion and withdrawal of the wire.

[0231] In the first device, the coupling and / or the source may include at least one longitudinal slot for entry or exit of the wire in a lateral direction transverse to the longitudinal axis of the wire.

[0232] In the first device, it may further include a locking mechanism arranged to capture the wire after lateral entry of the wire through the slot and release the wire for lateral exit of the wire through the slot.

[0233] In the first device, the locking mechanism may include at least one locking member rotatable about the wire for capturing and releasing the wire.

[0234] In the first device, the coupling may be arranged to clamp the wire when in any of the operating positions.

[0235] In the first device, the coupling includes a collet, and the collet may be radially compressible onto the wire in response to longitudinal movement or longitudinal compression of the collet.

[0236] In the first device, the collet includes at least one mating surface engaged with the source, and the surface may be inclined with respect to the longitudinal axis of the collet.

[0237] In the first apparatus, the mating surface can be defined by the tapered end of the collet.

[0238] In the first apparatus, the collet may be movable within the transducer that functions as the source, or longitudinally relative to the transducer.

[0239] In the first apparatus described above, a thread may be included between the collet and the transducer, and the thread may be arranged to move the collet longitudinally and to couple the collet to the transducer.

[0240] In the first apparatus described above, the wire extends through the source and may have portions that extend proximal and distal to the source, respectively.

[0241] In the first apparatus, the portion of the wire extending proximal may originate from the proximal end of the source.

[0242] In the first apparatus, the proximal portion of the wire may exit the source on an axis that crosses the longitudinal axis of the distal portion of the wire.

[0243] In the first device, the operating position can be marked on the wire.

[0244] In the first apparatus, the operating position may be characterized by the harmonics of the wire at the activation frequency of the source.

[0245] (Second device) An intravascular device for traversing an obstacle within a blood vessel, wherein the device is An electrically driven ultrasonic energy source, During use, the intravascular wire is excited, and ultrasonic energy is transmitted from the source along the wire, thereby connecting the wire to an active tip at the distal end of the wire. An apparatus, comprising: a signal acquisition and processing system configured to capture and respond to operating parameters of the apparatus when the active tip approaches or crosses an obstacle during use.

[0246] In the second apparatus, the signal acquisition and processing system may be configured to monitor fluctuations in the frequency and / or amplitude of the current drawn by the ultrasonic energy source, or the voltage dropped across the ultrasonic energy source.

[0247] In the second apparatus, the signal acquisition and processing system may be configured to modulate the excitation voltage applied to the ultrasonic energy source, or the excitation current supplied to the ultrasonic energy source.

[0248] In the second apparatus, the signal acquisition and processing system may be configured to control the ultrasonic energy source by changing the frequency and / or amplitude of the excitation voltage applied to the ultrasonic energy source.

[0249] In the second apparatus, the signal acquisition and processing system may be configured to drive the frequency of the excitation voltage by using the phase difference between the excitation voltage and the excitation current, in combination with the amplitude of the excitation voltage.

[0250] In the second apparatus, the signal acquisition and processing system may be configured to monitor fluctuations in the frequency or amplitude of the vibration of the wire through the coupling.

[0251] In the second apparatus, the signal acquisition and processing system may include an amplitude feedback controller and may be configured to use the resonance frequency as the operating point of control.

[0252] In the second apparatus, the signal acquisition and processing system may be configured to estimate the displacement of the active tip of the wire from the waveform in the wire determined from the fluctuation of the frequency of the wire's vibration.

[0253] In the second apparatus, the signal acquisition and processing system may be configured to use a numerical algorithm selected for a particular type of wire.

[0254] In the second apparatus, the signal acquisition and processing system may be configured to estimate areas mapped out by the displacement of the active tip of the wire in open and occluded vascular systems for gelatinous lesions, fibrous lesions, and calcified lesions.

[0255] In the second apparatus, the signal acquisition and processing system may be configured to monitor approach to an obstacle and / or to determine the characteristics of the obstacle from the captured operating parameters.

[0256] In the second apparatus, the signal acquisition and processing system may be configured to compare the relative contribution of the loss due to anatomical meandering when the active tip navigates the obstacle with the loss resulting from the active tip passing through the obstacle.

[0257] In the second apparatus, the signal acquisition and processing system may be configured to pulse or modify the drive signal to the ultrasonic energy source.

[0258] In the second apparatus, the signal acquisition and processing system may be configured to execute an algorithm specific to the intravascular wire type to estimate the deflection of the active tip when excited and to estimate the tunnel diameter extending through the obstacle.

[0259] In the second apparatus, the signal acquisition and processing system is: The modulation of the transmitted signal is monitored, and the voltage applied to the ultrasonic energy source is automatically controlled to compensate for background energy loss encountered in the wire when the active tip approaches the obstacle. The background energy loss may be distinguished from additional energy loss when the active tip passes through the obstacle, and the system may be configured to compensate for the background energy loss and maintain the displacement at the active tip.

[0260] The second apparatus may further include a manual override that is operable to modulate the power output of the ultrasonic energy source.

[0261] In the second apparatus, the signal acquisition and processing system may be configured to compare the captured operating parameters with stored data characterizing known obstacles, and to characterize the obstacles by reference to the comparison.

[0262] In the second apparatus, the signal acquisition and processing system may further include an output to a user interface and / or an external data acquisition system.

[0263] In the second apparatus, the signal acquisition and processing system may further include inputs from a user interface and / or an external data network.

[0264] In the second apparatus, the signal acquisition and processing system may be configured to modify or change the control algorithm in response to variations in the operating parameters of the apparatus resulting from the interaction of the active tip with an obstacle during use.

[0265] In the second apparatus, the signal acquisition and processing system may be configured to output data to an external data network, receive data from the network in response, and modify or change the control algorithm accordingly upon receiving data from the network.

[0266] In the second apparatus, the signal acquisition and processing system may be configured to output to the network data representing the fluctuations in the operating parameters of the apparatus resulting from the interaction of the active tip with an obstacle during use.

[0267] In the first or second apparatus, the source may include a transducer that vibrates at a frequency of 20 kHz to 60 kHz.

[0268] In the first or second apparatus, the transducer may vibrate at a frequency of 35 kHz to 45 kHz.

[0269] In the first or second apparatus, the transducer may vibrate at a frequency of 37 kHz to 43 kHz.

[0270] In the first or second apparatus, the transducer may vibrate at a frequency substantially equal to 40 kHz.

[0271] The first or second apparatus may further include a subsequent intravascular diagnostic or therapeutic device that can be transported distally along the wire into the patient's vascular system after the source has been uncoupled from the wire.

[0272] (Communication system) A communication system comprising either of the first or second devices, wherein the device communicates with a computer system configured to receive data from the device, optimize and update a control algorithm accordingly, and output the optimized and updated control algorithm to the device.

[0273] In the communication system, two or more such devices may communicate data with the computer system, and the computer system may be configured to optimize a control algorithm according to data received from a plurality of actions performed using the devices, and to output the optimized and updated control algorithm to the devices.

[0274] (First wire) An elongated intravascular wire for traversing an obstruction within a blood vessel, wherein the wire includes a coupling for transmitting ultrasonic energy from an ultrasonic energy source to an active tip at the distal end of the wire during use, the coupling being positioned to connect the source to the wire at any of a plurality of separate operating positions along the length of the wire for the transmission of ultrasonic energy to the active tip.

[0275] (Second wire) A long, slender intravascular wire for crossing an obstacle within a blood vessel, wherein the wire is During use, a coupling is provided along the wire for transmitting ultrasonic energy from an ultrasonic energy source to an active tip at the distal end of the wire. A cutting device on the coupling or the wire, the cutting device comprising: a cutting device for cutting or notching the wire in order to separate the coupling from the portion of the wire extending distal to the cutting device.

[0276] In the second wire, the cutting device may include at least one blade that is movable laterally with respect to the longitudinal axis of the wire.

[0277] (Third wire) A long, slender intravascular wire for crossing an obstacle within a blood vessel, wherein the wire is During use, the wire includes a coupling for transmitting ultrasonic energy from an ultrasonic energy source to an active tip at the distal end of the wire. The coupling includes a screw connector fixed to the proximal end of the wire, and a rotating sleeve, the rotating sleeve being movable to a second longitudinal position to connect and disconnect the sleeve from the screw connector and the wire, in order to engage with the screw connector at a first longitudinal position and rotate the screw connector to engage with the ultrasonic energy source, and then to a second longitudinal position to connect and disconnect the sleeve from the screw connector and the wire.

[0278] In the third wire, the first longitudinal position may be located proximal to the second longitudinal position.

[0279] (Fourth wire) An elongated intravascular wire for traversing an obstruction within a blood vessel, the wire comprising a proximal section, a distal tip section having a smaller diameter than the proximal section, and a distally tapered intermediate section extending between the proximal section and the distal tip section, wherein the wire is substantially sleeveless along its entire length.

[0280] The fourth wire may include at least one welded joint between at least two of the sections.

[0281] In the fourth wire, the distal tip section may include a spherical distal tip.

[0282] In the fourth wire, the distal tip section may include a distal portion that is angularly offset with respect to the longitudinal axis of the wire.

[0283] In the fourth wire, the marker band may surround at least the distal tip section.

[0284] The fourth wire may have a total length of 500 mm to 2500 mm.

[0285] In the fourth wire, the proximal section may have a uniform diameter along its length.

[0286] In the fourth wire, the diameter of the proximal section may be 0.014 inches to 0.035 inches (approximately 0.36 mm to approximately 0.89 mm).

[0287] In the fourth wire, the proximal section of the wire may have a length of 500 mm to 2000 mm.

[0288] In the fourth wire, the length of each section is a function or multiple of λ / 4, where λ may be a driving frequency that causes resonance within the wire.

[0289] In the fourth wire, the distal section may be tapered or have a constant diameter along its length.

[0290] In the fourth wire, the distal section may have a diameter of 0.003 inches to 0.014 inches (approximately 0.08 mm to approximately 0.36 mm).

[0291] (First intravascular device) An intravascular device comprising one of the first to fourth wires described above, and an ultrasonic energy source coupled to the wire.

[0292] (unit) An activation unit for transmitting ultrasonic energy into a long, slender intravascular wire, wherein the unit comprises: The source of the ultrasonic energy, A unit including a coupling arranged to connect the source to the wire at one of a plurality of separate operating positions along the length of the wire.

[0293] In the unit, the coupling may be arranged to allow relative longitudinal movement between the source and the wire when moving between the operating positions.

[0294] In the unit, the coupling may be positioned to allow the relative longitudinal movement while remaining attached to the wire.

[0295] In the unit, the coupling may be arranged to allow the relative longitudinal movement by being detached from the wire and reattached to the wire.

[0296] In the aforementioned unit, the source may include a transducer that vibrates at a frequency of 20 kHz to 60 kHz.

[0297] In the aforementioned unit, the transducer may vibrate at frequencies of 35 kHz to 45 kHz.

[0298] In the aforementioned unit, the transducer may vibrate at frequencies of 37kHz to 43kHz.

[0299] In the unit, the transducer may oscillate at a frequency of 40 kHz or substantially equal to 40 kHz.

[0300] The unit may further include visual, haptic, and / or auditory user interfaces.

[0301] (Activation Unit) An activation unit for transmitting ultrasonic energy into a long, slender intravascular wire, wherein the activation unit is The ultrasonic energy source having an ultrasonic transducer, A coupling arranged to connect the source to the elongated intravascular wire at one of a plurality of individual operating positions along the length of the elongated intravascular wire, which are positions for transmitting the ultrasonic energy to the elongated intravascular wire, and the coupling arranged to clamp the elongated intravascular wire when it is in one of the operating positions, Includes, and, The slender intravascular wire extends through the coupling and the source, and the activation unit is positioned such that it has portions extending proximal and distal to the activation unit, respectively. The excitation of the elongated intravascular wire portion extending proximal to the activation unit is attenuated. Activation unit.

[0302] In the activation unit, the coupling may be positioned to slide along the elongated intravascular wire while remaining attached to it, thereby enabling relative longitudinal movement between the source and the elongated intravascular wire when moving between the operating positions.

[0303] In the activation unit, the coupling may be detached from the elongated intravascular wire and reattached to the elongated intravascular wire, thereby enabling relative longitudinal movement between the source and the elongated intravascular wire when moving between the operating positions.

[0304] In the activation unit, the ultrasonic transducer may be configured to vibrate at a frequency of 20 kHz to 60 kHz.

[0305] The activation unit may further include a visual user interface, a haptic user interface, and / or an auditory user interface configured to communicate performance and progress when advancing through a vascular obstruction, or to provide feedback on the composition and length of the obstruction.

[0306] (Second intravascular device) An intravascular device for traversing an obstacle within a blood vessel, wherein the intravascular device is One of the activation units mentioned above, An elongated intravascular wire extending through the coupling and source of the activation unit, and having portions extending proximal and distal to the coupling and source, respectively, Includes, The coupling is an intravascular device that, during use, transmits the ultrasonic energy from the source to an active tip at the distal end of the elongated intravascular wire along the elongated intravascular wire.

[0307] In the second intravascular device, the coupling is detached from the elongated intravascular wire and reattached to the elongated intravascular wire, thereby enabling relative longitudinal movement between the source and the elongated intravascular wire when moving between the operating positions. The coupling and / or source may have a bore extending along the longitudinal axis of the elongated intravascular wire and may include a distal opening and a proximal or lateral opening communicating with the bore for longitudinal insertion and withdrawal of the elongated intravascular wire into the bore.

[0308] In the second intravascular device, the coupling is detached from the elongated intravascular wire and reattached to the elongated intravascular wire, thereby enabling relative longitudinal movement between the source and the elongated intravascular wire when moving between the operating positions. The coupling and / or source has a bore extending along the longitudinal axis of the elongated intravascular wire, and may include at least one longitudinal slot extending along the longitudinal direction of the bore, communicating with the bore in a lateral direction across the longitudinal axis of the elongated intravascular wire, for the entry of the elongated intravascular wire into the bore or the exit of the elongated intravascular wire from the bore.

[0309] The second intravascular device may further include at least one locking member that is rotatable around the elongated intravascular wire and the bore, and which can open and close the longitudinal slot by being rotated, in order to capture the elongated intravascular wire after it has entered the bore laterally through the longitudinal slot and to release the elongated intravascular wire when it has exited the bore laterally through the longitudinal slot.

[0310] In the second intravascular device, the coupling includes a collet, which may be radially compressible on the elongated intravascular wire in response to longitudinal movement or compression of the collet.

[0311] In the second intravascular device, the collet includes at least one mating surface that engages with the source, the mating surface may be inclined with respect to the longitudinal axis of the collet.

[0312] In the second intravascular device, the mating surface can be defined by the tapered end of the collet.

[0313] In the second intravascular device, the collet may be movable longitudinally within or relative to the ultrasonic transducer.

[0314] In the second intravascular device, a thread may be included between the collet and the ultrasonic transducer, wherein the thread may be arranged to move the collet longitudinally and to couple the collet to the ultrasonic transducer.

[0315] In the second intravascular device, the proximal portion of the elongated intravascular wire may extend from the proximal end of the source.

[0316] In the second intravascular device, the proximal portion of the elongated intravascular wire may exit the source on an axis that crosses the longitudinal axis of the distal portion of the elongated intravascular wire.

[0317] In the second intravascular device, the operating position can be marked on the elongated intravascular wire.

[0318] In the second intravascular device, when the ultrasonic transducer is operated at the frequency that drives it, if the source is attached to the elongated intravascular wire at any of the operating positions, harmonics may be generated in the elongated intravascular wire.

[0319] (First method) A method for reducing obstacles in a passageway, wherein the method is The ultrasonic energy source is coupled to the wire at one of several individual operating positions along the length of the elongated wire, A method comprising transmitting ultrasonic vibrations from the source along the wire to vibrate an active tip at the distal end of the wire that is in contact with the obstacle.

[0320] The first method described above may include providing relative longitudinal movement between the source and the wire when moving between the operating positions.

[0321] The first method may include causing the relative longitudinal movement while the source remains attached to the wire.

[0322] The first method may include moving the wire longitudinally while holding the source in a substantially stationary state.

[0323] The first method may include detaching the source from the wire and reattaching the source to the wire at different longitudinal positions to bring about the relative longitudinal movement.

[0324] The first method described above may include moving the source longitudinally while holding the wire in a substantially stationary position.

[0325] The first method described above may include removing the source from the wire or attaching the source to the wire by relative movement between the source and the wire in a lateral direction across the longitudinal axis of the wire.

[0326] The first method may include clamping the wire when the source is in any of the operating positions.

[0327] (Second method) A method for reducing obstacles in a passageway, wherein the method is The process involves transmitting ultrasonic vibrations from an ultrasonic energy source along a long, thin wire to vibrate the active tip at the distal end of the wire that is in contact with the obstacle, A method comprising delivering a subsequent diagnostic or therapeutic device distally along the wire.

[0328] In the second method described above, the source can be removed from the wire before delivering the subsequent device along the wire.

[0329] (Third method) A method for reducing obstacles in a passageway, wherein the method is The method involves transmitting ultrasonic vibrations along the wire from an electrically driven source coupled to the wire to vibrate the active tip at the distal end of the wire that is in contact with the obstacle, A method comprising sensing the response of a vibrating wire to an obstacle when the active tip encounters and crosses the obstacle.

[0330] The third method may further include comparing the sensed data representing the response of the vibrating wire with stored data representing the corresponding response of the vibrating wire to an interaction with a known obstacle.

[0331] The third method may further include adjusting the amplitude or frequency of the ultrasonic vibration transmitted along the wire to the active tip in response to sensing the response of the vibrating wire.

[0332] The third method described above may include sensing the amplitude of the vibration of the wire and controlling the source to maintain the resonant frequency within the wire.

[0333] The third method may include modifying or changing the control algorithm in response to variations in the response of the vibrating wire.

[0334] The third method described above may include outputting data to an external data network, receiving data from the network in response, and modifying or changing the control algorithm accordingly upon receiving data from the network.

[0335] The third method may include outputting data representing the variation in the response of the vibrating wire to the network.

[0336] The third method described above may include outputting data to an external computer system, optimizing and updating a control algorithm in the external computer system according to the data, outputting the optimized and updated control algorithm from the external computer system, and controlling the vibration of the wire using the optimized and updated control algorithm.

[0337] In the third method described above, the computer system may optimize the control algorithm according to the data received from the multiple procedures.

[0338] (Fourth method) A method for characterizing an intravascular obstruction, the method comprising comparing measured data representing the response of a pre-delivered vibrating intravascular wire to interaction with the obstruction with stored data representing the response of a corresponding vibrating intravascular wire to interaction with a known obstruction.

[0339] The fourth method may include adjusting the vibration of the pre-delivered intravascular wire in response to the comparison between the measured data and the stored data.

[0340] The fourth method may include a preliminary step of selecting a particular type of intravascular wire, and a preliminary step of selecting an algorithm specific to the type of intravascular wire for use in determining the response of the selected wire to an obstacle.

Claims

1. An intravascular device for crossing an obstacle within a blood vessel, wherein the device is An electrically driven ultrasonic energy source, During use, the wire inside the blood vessel is excited, and ultrasonic energy is transmitted along the wire from the ultrasonic energy source, thereby connecting the wire to the active tip at the distal end of the wire. The system includes a signal acquisition and processing system configured to capture and respond to the operating parameters of the device when the active tip approaches or crosses an obstacle during use, The signal acquisition and processing system is as follows: The coupling is configured to monitor the frequency variation of the vibration of the wire, A device configured to estimate the displacement of the movement of the active tip of the wire from the waveform of the wire determined from the fluctuation of the frequency of the vibration of the wire.

2. The apparatus according to claim 1, wherein the signal acquisition and processing system is configured to modulate the excitation voltage applied to the ultrasonic energy source or the excitation current supplied to the ultrasonic energy source.

3. The apparatus according to claim 2, wherein the signal acquisition and processing system is configured to control the ultrasonic energy source by changing the frequency of the excitation voltage applied to the ultrasonic energy source and / or the amplitude of the excitation voltage applied to the ultrasonic energy source.

4. The apparatus according to claim 3, wherein the signal acquisition and processing system is configured to drive the frequency of the excitation voltage by using the phase difference between the excitation voltage and the excitation current in conjunction with the amplitude of the excitation voltage.

5. The signal acquisition and processing system is: The coupling is configured to monitor the amplitude variation of the vibration of the wire, and The apparatus according to any one of claims 1 to 4, comprising an amplitude feedback controller, configured to use a resonant frequency as the operating point of the control.

6. The apparatus according to any one of claims 1 to 5, wherein the signal acquisition and processing system is configured to use a numerical algorithm selected for a particular type of wire.

7. The apparatus according to any one of claims 1 to 6, wherein the signal acquisition and processing system is configured to estimate areas mapped out by the displacement of the active tip of the wire in open and occluded vascular systems for gelatinous lesions, fibrous lesions and calcified lesions.

8. The apparatus according to any one of claims 1 to 7, wherein the signal acquisition and processing system is configured to monitor approach to an obstacle and / or to determine the characteristics of the obstacle from the captured operating parameters.

9. The apparatus according to any one of claims 1 to 8, wherein the signal acquisition and processing system is configured to compare the relative contribution of the loss due to anatomical meandering when the active tip navigates the obstacle with the loss resulting from the active tip passing through the obstacle.

10. The apparatus according to claim 9, wherein the signal acquisition and processing system is configured to pulse or change the drive signal to the ultrasonic energy source.

11. The apparatus according to any one of claims 1 to 10, wherein the signal acquisition and processing system is configured to perform an algorithm specific to the type of wire in the blood vessel to estimate the deflection of the active tip when excited and to estimate the tunnel diameter extending through the obstacle.

12. The signal acquisition and processing system is: The modulation of the transmitted signal is monitored, and the voltage applied to the ultrasonic energy source is automatically controlled to compensate for background energy loss encountered in the wire when the active tip approaches the obstacle. The apparatus according to any one of claims 1 to 11, wherein the background energy loss is distinguished from additional energy loss when the active tip passes through the obstacle, and the apparatus is configured to compensate for the background energy loss and maintain the displacement at the active tip.

13. The apparatus according to any one of claims 1 to 12, wherein the signal acquisition and processing system is configured to compare the captured operating parameters with stored data characterizing known obstacles, and to characterize the obstacles with reference to the comparison.

14. The apparatus according to any one of claims 1 to 13, wherein the signal acquisition and processing system is configured to modify or change the control algorithm in response to variations in the operating parameters of the apparatus resulting from the interaction of the active tip with an obstacle during use.

15. The apparatus according to any one of claims 1 to 14, wherein the signal acquisition and processing system is configured to output data to an external data network, receive data from the external data network in response, and modify or change the control algorithm accordingly when data is received from the external data network.

16. The apparatus according to claim 15, wherein the signal acquisition and processing system is configured to output to the external data network data representing the fluctuations in the operating parameters of the apparatus resulting from the interaction of the active tip with an obstacle during use.

17. The apparatus according to any one of claims 1 to 16, further comprising a subsequent intravascular diagnostic or therapeutic device that can be transported distally along the wire into the patient's vascular system after the ultrasonic energy source has been uncoupled from the wire.

18. A communication system comprising the apparatus described in any one of claims 1 to 17, wherein the apparatus communicates with a computer system configured to receive data from the apparatus, optimize and update a control algorithm accordingly, and output the optimized and updated control algorithm to the apparatus.

19. The communication system according to claim 18, wherein two or more such devices communicate data with the computer system, and the computer system is arranged to optimize a control algorithm according to data received from a plurality of actions performed using the devices, and to output the optimized and updated control algorithm to the devices.

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