Guidewires

Abstract

A guidewire configured to traverse a catheter without exiting a side hole of the catheter for placement of a minimally invasive miniaturized percutaneous mechanical circulatory or ventricular assist device across the heart. The guidewire includes a proximal end, a distal end, and an elongated flexible body extending therebetween. The guidewire can have variable flexibility over its length via variable diameter and tapered sections that make up its core, and one or more coils that surround and are connected to sections of the core to prevent kinking. The guidewire can have one or more radiopaque markers and one or more visual markers for ease of use.

Description

[Technical field]

[0001] INCORPORATION BY REFERENCE TO PRIORITY APPLICATION Any and all applications for which a claim of foreign or domestic priority is identified in an Application Data Sheet filed with this application are hereby incorporated by reference under 37 CFR 1.57. For example, this application claims priority to U.S. Provisional Patent Application No. 63 / 224,326, entitled "GUIDEWIRE," filed July 21, 2021, the entire contents of which are incorporated by reference herein in their entirety for all purposes and form a part hereof. [Background technology]

[0002] background Mechanical circulatory support systems may be used to help pump blood during various medical procedures and / or as therapy for certain cardiac conditions. For example, cardiogenic shock (CS) is a common cause of death and remains difficult to manage despite advances in treatment options. CS is caused by severe impairment of myocardial function, resulting in reduced cardiac output, end-organ hypoperfusion, and hypoxia. Clinically, this manifests as hypotension refractory to volume resuscitation with characteristics of end-organ hypoperfusion requiring immediate pharmacological or mechanical intervention. Acute myocardial infarction (MI) accounts for approximately >80% of CS patients.

[0003] Percutaneous coronary intervention (PCI) is a non-surgical procedure to revascularize stenotic coronary arteries. PCI includes various techniques such as balloon angioplasty, stent implantation, rotablation and lithotripsy. PCI is considered high-risk if the patient has relevant comorbidities (e.g., frail or elderly), the PCI itself is very complicated (e.g., bifurcation or total occlusion), or the hemodynamic status is difficult (e.g., impaired ventricular function).

[0004] Small catheter-based intracardiac blood pumps have been developed for percutaneous insertion into the patient's body as acute therapy for CS and for temporary support during PCI. However, existing solutions for mechanical circulatory support systems have various performance deficiencies, such as insufficient blood flow, the requirement for continuous motor purging in the pump, undesirably high hemolysis, and poor sensing of hemodynamic parameters. Furthermore, existing mechanical circulatory support systems can be difficult to place in the desired location of the body, difficult to maintain in place during the procedure, difficult to visualize, and difficult to use. Thus, a need remains for a mechanical circulatory support system with features that overcome these and other shortcomings. Summary of the Invention

[0005] overview Each of the embodiments disclosed herein has multiple aspects, no single one of which is solely responsible for the desirable properties of the present disclosure. Without limiting the scope of the present disclosure, its more prominent features will now be briefly discussed. After reviewing this discussion, and particularly after reading the section entitled "Detailed Description," one will appreciate how the features of the embodiments described herein provide advantages over existing systems, devices, and methods for mechanical circulatory assist systems.

[0006] The following description describes non-limiting examples of some embodiments of the mechanical circulatory assist devices, systems, and methods. Other embodiments of the systems and methods of the present disclosure may or may not include the features described herein. Furthermore, the benefits and advantages disclosed may only apply to certain embodiments and should not be used to limit the present disclosure.

[0007] A first aspect relates to a guidewire configured to traverse a catheter having one or more side holes, the guidewire including a proximal end, a distal end having a distal advancement segment configured to traverse distally through the catheter without exiting the catheter's side holes, and an elongate flexible body extending between the proximal and distal ends, the elongate flexible body having a distal region extending between a distal transition and the distal end, the distal region having a spiral coil shape.

[0008] A second aspect relates to the guidewire of the first aspect, wherein the distal advancement segment includes an elongated straight tip.

[0009] A third aspect relates to the guidewire of the first or second aspect, wherein the distal advancement segment has a length that is greater than a maximum diameter of the side hole or holes.

[0010] A fourth aspect relates to a guidewire of any of the previous aspects, wherein the distal advancement segment has a minimum length of about 0.5 mm to about 3.5 mm.

[0011] A fifth aspect relates to a guidewire according to any of the previous aspects, wherein the maximum angle between the central axis of the distal advancement segment and the longitudinal axis of the catheter is between about 17° and about 25°.

[0012] A sixth aspect relates to the guidewire of the first aspect, wherein the distal advancement segment has a curved advancement segment extending from an inflection point at the distal end of the spiral coil configuration.

[0013] A seventh aspect relates to the guidewire of the sixth aspect, wherein the spiral coil configuration is concave in a first direction and the distal advancement segment is concave in a second direction.

[0014] An eighth aspect relates to the guidewire of the sixth aspect, wherein the distal advancement segment includes a first curved region having a first inflection point and a second curved region having a second inflection point.

[0015] A ninth aspect relates to the guidewire of the eighth aspect, wherein the first curved region and / or the second curved region comprises an arc length that is greater than a maximum diameter of the one or more side holes.

[0016] A tenth aspect relates to the guidewire of the ninth aspect, wherein the arc length is greater than 0.5 mm.

[0017] An eleventh aspect relates to a guidewire described in any of the eighth to tenth aspects, wherein the maximum angle between the longitudinal axis of the catheter and the central axis of a portion of the advancement segment extending distally from the second inflection point is between about 5° and about 85°.

[0018] A twelfth aspect relates to the guidewire of the eleventh aspect, wherein the maximum angle between the longitudinal axis of the catheter and the central axis of a portion of the advancement segment extending distally from the second inflection point is between about 10° and about 60°.

[0019] A thirteenth aspect relates to the guidewire according to any one of the eighth to twelfth aspects, wherein a maximum length of a portion of the advancement segment extending distally from the second inflection point is from about 0.3 mm to about 4 mm.

[0020] A fourteenth aspect relates to the guidewire according to any one of the eighth to thirteenth aspects, wherein the radius of curvature of the first inflection point and / or the second inflection point is larger than the radius of the one or more side holes.

[0021] A fifteenth aspect relates to the guidewire of the fourteenth aspect, wherein the radius of curvature of the first inflection point and / or the second inflection point is about 0.5 mm to about 0.8 mm.

[0022] A sixteenth aspect relates to a guidewire of any of the preceding aspects, wherein the advancement segment has a maximum cross-sectional diameter that is greater than or equal to a diameter of the side hole or holes.

[0023] A seventeenth aspect relates to a guidewire of any of the preceding aspects, wherein the advancement segment is spheroidal.

[0024] An eighteenth aspect relates to a guidewire according to any of the previous aspects, wherein the advancement segment has a maximum cross-sectional diameter of between 0.8 mm and 1 mm.

[0025] A nineteenth aspect relates to a guidewire of any of the previous aspects, wherein the distal end has a rounded shape.

[0026] A twentieth aspect relates to a guidewire of any of the preceding aspects, further comprising a proximal region extending between the proximal transition and the proximal end, the proximal region configured to facilitate movement of the guidewire through a non-linear pathway.

[0027] A twenty-first aspect relates to a method of delivering a device to a patient's cardiovascular system, the method including delivering a first guidewire to the patient's cardiovascular system, advancing a catheter over the first guidewire, the catheter having one or more side holes, removing the first guidewire from the catheter, and advancing a second guidewire through the catheter, the second guidewire being a guidewire according to any of the previous aspects and configured to bypass the holes in the catheter as the second guidewire advances through the catheter. The method also includes removing the catheter from the second guidewire, feeding a proximal end of the second guidewire into a distal end of the device, and advancing the device over the second guidewire into the patient's cardiovascular system.

[0028] A twenty-second aspect relates to the method of the twenty-first aspect, wherein the apparatus includes a heart pump.

[0029] A twenty-third aspect relates to the method of either the twenty-first or twenty-second aspect, wherein the first guidewire has a diameter of 0.035 inches.

[0030] A twenty-fourth aspect relates to the method according to any one of the twenty-first to twenty-third aspects, wherein the second guide wire has a diameter of 0.018 inches.

[0031] Disclosed herein is a guidewire configured to traverse a catheter having one or more side holes, the guidewire including a proximal end, a distal end, and an elongated flexible body extending between the proximal end and the distal end. The distal end may include a distal advancement segment configured to traverse distally through the catheter without exiting the catheter's side hole. The elongated flexible body may include a distal region extending between a distal transition and the distal end, the distal region comprising a spiral coil shape.

[0032] In the above guidewires or other implementations described herein, one or more of the following features may also be provided: In some implementations, the distal advancement segment comprises an elongated straight tip. In some implementations, the distal advancement segment comprises a length that is greater than a maximum diameter of the one or more side holes. In some implementations, the minimum length of the distal advancement segment is between about 0.5 mm and about 3.5 mm. In some implementations, the maximum angle between a central axis of the distal advancement segment and a longitudinal axis of the catheter is between about 17° and about 25°. In some implementations, the distal advancement segment comprises a curved advancement segment extending from an inflection point at a distal end of a spiral coil shape. In some implementations, the spiral coil shape is concave in a first direction and the distal advancement segment is concave in a second direction. In some implementations, the distal advancement segment comprises a first curved region having a first inflection point and a second curved region having a second inflection point. In some implementations, the first curved region and / or the second curved region include an arc length that is greater than a maximum diameter of the one or more side holes. In some implementations, the arc length is greater than about 0.5 mm. In some implementations, the maximum angle between the longitudinal axis of the catheter and the central axis of the portion of the distal advancement segment that extends distally from the second inflection point is between about 5° and about 85°. In some implementations, the maximum angle between the longitudinal axis of the catheter and the central axis of the portion of the distal advancement segment that extends distally from the second inflection point is between about 10° and about 60°. In some implementations, the maximum length of the portion of the distal advancement segment that extends distally from the second inflection point is between about 0.3 mm and about 4 mm. In some implementations, the radius of curvature of the first inflection point and / or the second inflection point is greater than a radius of the one or more side holes. In some implementations, the radius of curvature of the first inflection point and / or the second inflection point is about 0.5 mm to about 0.8 mm. In some implementations, the diameter of the distal advancement segment at its largest cross section is equal to or greater than the diameter of the side hole or holes. In some implementations, the distal advancement segment is spheroidal. In some implementations, the diameter of the distal advancement segment at its largest cross section is about 0.8 mm to about 1 mm. In some implementations, the distal end is rounded in shape.In some implementations, the guidewire further includes a proximal region extending between the proximal transition and the proximal end, the proximal region configured to facilitate movement of the guidewire through a nonlinear path. In some implementations, the elongated flexible body includes a core including multiple segments having different diameters. In some implementations, the diameter of each of the multiple segments of the core is between about 0.10 mm and about 0.5 mm. In some implementations, the multiple segments having different diameters are connected to each other by one or more tapered, chamfered, conical, or frustoconical transition segments, each of the tapered, chamfered, conical, or frustoconical transition segments having a diameter that varies over its length. In some implementations, the guidewire has variable flexibility along its length. In some implementations, the elongated flexible body further includes one or more coils of wire surrounding the core. In some implementations, the one or more coils of wire surrounding the core prevent the guidewire from kinking. In some implementations, the one or more coils of wire surround at least a portion of the core of the distal region and / or the proximal region. In some implementations, the elongate flexible body further includes a body region and / or a pump region. In some implementations, the distal region and / or the proximal region have a diameter smaller than a diameter of the body region and / or the pump region. In some implementations, the one or more coils of wire surround at least a portion of the core of the body region and / or the pump region. In some implementations, the guidewire has a length of about 2770 mm to about 4030 mm. In some implementations, the distal region of the guidewire includes one or more radiopaque markers. In some implementations, the distal region of the guidewire includes a first radiopaque marker at or adjacent to the distal end, a second radiopaque marker about 20 mm to about 180 mm from the distal end, and / or a third radiopaque marker about 200 mm from the distal end. In some implementations, the guidewire includes a plurality of radiopaque markers evenly spaced along at least a portion of its length to provide a scale that can be visualized by fluoroscopy.In some implementations, the proximal region of the guidewire includes one or more visual markers.

[0033] Disclosed herein is a method of delivering a device to a patient's cardiovascular system, the method comprising: delivering a first guidewire to the patient's cardiovascular system; advancing a catheter over the first guidewire, the catheter comprising one or more side holes; removing the first guidewire from the catheter; advancing a second guidewire through the catheter, the second guidewire comprising a guidewire according to any one of claims 1-35, the second guidewire being configured to bypass the one or more side holes of the catheter as the second guidewire is advanced through the catheter; removing the catheter from the second guidewire; feeding a proximal end of the second guidewire to a distal end of a device; and advancing the device over the second guidewire into the patient's cardiovascular system.

[0034] In the above methods or other implementations described herein, one or more of the following features may also be provided: In some implementations, the apparatus comprises a cardiac pump. In some implementations, the first guidewire has an outer diameter of about 0.035 inches. In some implementations, the second guidewire has a minimum outer diameter of about 0.018 inches. In some implementations, advancing the second guidewire into the patient's cardiovascular system includes advancing the second guidewire such that the first radiopaque marker and / or the second radiopaque marker are positioned within the patient's left ventricle and the third radiopaque marker is positioned within the patient's aorta.

[0035] BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims taken in conjunction with the accompanying drawings. The present disclosure will be described with further specificity and detail through the use of the accompanying drawings, with the understanding that these drawings illustrate only some embodiments according to the present disclosure and should not be considered as limiting its scope. In the following detailed description, reference is made to the accompanying drawings, which form a part of this specification. In the drawings, similar symbols typically identify similar components unless the context dictates otherwise. The exemplary embodiments described in the detailed description, drawings, and claims are not intended to be limiting. Other embodiments may be utilized and other changes may be made without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that aspects of the present disclosure, as generally described herein and illustrated in the drawings, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are expressly intended and made a part of this disclosure. [Brief description of the drawings]

[0036] [Figure 1A] FIG. 1A is a cross-sectional view of a guidewire positioned across the aortic valve and extending into the left ventricle of the heart, according to some embodiments. [Figure 1B] FIG. 1B is a cross-sectional view of a guidewire positioning a catheter-carried mechanical circulatory support (MCS) device across the aortic valve, according to some embodiments. [Diagram 2] FIG. 2 illustrates a schematic of an MCS system inserted into the body over a guidewire via an access path from the femoral artery to the left ventricle, according to some embodiments. [Diagram 3] FIG. 3 is a side view of a guidewire inserted through the MCS system, according to some embodiments. [Figure 4] FIG. 4 illustrates an embodiment of a placement guidewire. [Figure 5A] 5A-5C show an embodiment of a distal portion of a placement guidewire. [Figure 5B]5A-5C show an embodiment of a distal portion of a placement guidewire. [Figure 5C] 5A-5C show an embodiment of a distal portion of a placement guidewire. [Figure 6A] FIG. 6A illustrates an embodiment of a distal portion of a placement guidewire having an elongated distal advancement segment. [Figure 6B] FIG. 6B shows an enlarged view of the distal advancement segment of the guidewire shown in FIG. 6A. [Figure 6C] FIG. 6C shows an enlarged cross-sectional view of the distal advancement segment of the guidewire of FIG. 6A positioned within a catheter. [Figure 7A] FIG. 7A illustrates an embodiment of a distal portion of a placement guidewire having a curved distal advancement segment. [Figure 7B] FIG. 7B shows a close-up view of the distal advancement segment of the guidewire shown in FIG. 7A. [Figure 7C] FIG. 7C illustrates an embodiment of a distal portion of a placement guidewire having a curved distal advancement segment. [Figure 7D] FIG. 7D shows an enlarged cross-sectional view of the distal advancement segment of the guidewire of FIG. 7A positioned within a catheter. [Figure 8A] FIG. 8A illustrates an embodiment of a distal portion of a placement guidewire having an enlarged distal advancement segment. [Figure 8B] FIG. 8B shows an enlarged cross-sectional view of a guidewire with an enlarged distal advancement segment positioned within a catheter. [Figure 9A] FIG. 9A shows a cross-sectional view of a portion of an embodiment of a distal region of a guidewire. [Figure 9B] FIG. 9B shows a cross-sectional view of a portion of an embodiment of a distal region of a guidewire. [Figure 10A] FIG. 10A illustrates an embodiment of a guidewire. [Figure 10B] FIG. 10B shows a cross-sectional view of the guidewire of FIG. 10A. [Figure 11A] FIG. 11A illustrates an embodiment of a guidewire. [Figure 11B] FIG. 11B shows a cross-sectional view of the guidewire of FIG. 11A. [Figure 11C] FIG. 11C shows a cross-sectional view of the guidewire of FIG. 11B. [Figure 12] FIG. 12 illustrates a proximal region of a guidewire according to some embodiments. [Figure 13] FIG. 13 illustrates a proximal region of a guidewire according to some embodiments. [Figure 14] FIG. 14 illustrates a proximal region of a guidewire according to some embodiments. [Figure 15] FIG. 15 shows a perspective view of a distal pump region of an MCS device according to some embodiments. [Figure 16] FIG. 16 shows a side view of the distal region of the MCS device of FIG. 15, showing a removable guidewire accessory with a guidewire guide tube in place defining a guidewire pathway. [Figure 17] FIG. 17 shows an enlarged cross-sectional view of a portion of the distal region of the MCS device showing a portion of the guidewire pathway. [Figure 18] FIG. 18 shows a perspective view of the bend relief of the MCS device. [Figure 19] FIG. 19 shows a cross-sectional view of a portion of the distal region of the MCS device showing a portion of the guidewire pathway. [Figure 20A] 20A-20C show top, side and side views of a guidewire port 80 within a bend relief. [Figure 20B] 20A-20C show top, side and side views of a guidewire port 80 within a bend relief. [Figure 20C] 20A-20C show top, side and side views of a guidewire port 80 within a bend relief. [Figure 21] FIG. 21 shows a perspective view of a portion of the distal region of the MCS device showing the connection between the motor housing and the bend relief. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] While the above-identified drawing figures set forth embodiments of the present disclosure, other embodiments are contemplated, as described in the detailed description. The present disclosure presents exemplary embodiments by representation and not by limitation. Numerous other modifications and embodiments can be devised by those skilled in the art which fall within the scope and spirit of the principles of the embodiments of the present disclosure.

[0038] Detailed Description The following detailed description is directed to certain embodiments of the development. In this description, reference is made to the drawings, and for clarity, like parts or steps may be designated with like numerals throughout. References herein to "one embodiment," "an embodiment," or "in some embodiments" mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the invention. The appearances of the phrases "one embodiment," "embodiment," or "in some embodiments" in various places throughout this specification do not necessarily all refer to the same embodiment, nor are separate or alternative embodiments necessarily mutually exclusive with other embodiments. Furthermore, various features are described that may be exhibited by some embodiments and not by other embodiments. Similarly, various requirements are described that may be required in some embodiments but not in other embodiments. Reference will now be made in detail to embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used throughout the drawings to refer to the same or similar parts.

[0039] A guidewire for use in minimally invasive procedures is provided. Certain embodiments of the guidewire described herein can be used in a mechanical circulatory support system or a mechanical left ventricular assist system, for example, for placement of a mechanical circulatory support (MCS) device or a ventricular assist device (VAD). The guidewire described herein can advantageously improve the ease of use and / or address challenges associated with the use of an MCS device or a VAD. For example, the guidewire described herein can improve the ability to detect guidewire misplacement without the need to inject contrast to visualize the patient's anatomy, improve the ability to determine the depth of the patient's left ventricle where the MCS device / VAD is placed, improve the ability to visualize relative scale, improve the handling, control, and / or pushability of the guidewire, and / or enable faster procedures.

[0040] FIG 1A is a schematic diagram of a guidewire 100 positioned across the aortic valve 91 with its distal end positioned in the left ventricle 93. FIG 1B is a schematic diagram of the distal end of an embodiment of an MCS system 10 having a pump 22 attached to the end of a catheter 16 positioned in the heart over the guidewire 100. FIG 2 shows a schematic diagram of an MCS system 10 inserted into the body over a guidewire 100 via an access path from the femoral artery to the left ventricle, according to some embodiments. Access may be achieved via a transfemoral, transaxillary, transaortic, or transapical approach, etc.

[0041] As shown in FIG. 1A, the distal region of guidewire 100 may include one or more radiopaque markers to aid in positioning guidewire 100 within the patient's cardiovascular system and / or to ensure that any device, such as an MCS device or VAD, positioned by guidewire 100 remains in a desired location. For example, guidewire 100 may include a first radiopaque marker 151 at or adjacent the distal end of guidewire 100. In some embodiments, guidewire 100 may include a second radiopaque marker 152 positioned proximally from the distal end. For example, second radiopaque marker 152 may be positioned at or about 20 mm to 180 mm at or about 180 mm from the distal end. In certain embodiments, guidewire 100 may include a third radiopaque marker 153, which may be positioned proximally from the distal end. The third radiopaque marker 153 may be located at or about 200 mm from the distal end. Guidewire 100 may include any of the first radiopaque marker 151, the second radiopaque marker 152, and the third radiopaque marker 153, alone or in combination with any or both of the other radiopaque markers.

[0042] In certain embodiments, when properly positioned within the cardiovascular system, the first radiopaque marker 151 and / or the second radiopaque marker 152 may be positioned within the left ventricle 93 and the third radiopaque marker may be positioned within the ascending aorta 95. In some embodiments, the second radiopaque marker 152 is located at or about 100 mm to at or about 180 mm, preferably at or about 160 mm, or at or about 20 mm to at or about 60 mm, preferably at or about 40 mm, from the first radiopaque marker 151. The guidewire 100 may be positioned such that the aortic valve 91 is located between the third radiopaque marker 153 and the first or second radiopaque marker 151 / 152. In some embodiments, the guidewire 100 includes multiple radiopaque markers along at least a portion of its length to provide a scale that may be visualized by fluoroscopy. Such multiple radiopaque markers may be located along or adjacent to a distal region of the guidewire 100. Additionally, such multiple radiopaque markers may be evenly or substantially evenly spaced, such as, for example, one every 10 mm or about every 10 mm, along at least a portion of the guidewire 100. Such multiple radiopaque markers may be used by the physician / user as a guide to determine the depth to place the MCS device and / or VAD and / or may be used to capture information that may be used for subsequent treatment or therapy (e.g., measurements of patient-specific anatomy, etc.). When included in guidewire 100, the radiopaque markers can be used as guides for positioning the MCS device and / or VAD, particularly if the MCS device and / or VAD have their own radiopaque markers (e.g., the relative positions of the radiopaque markers of guidewire 100 and the radiopaque markers of the MCS device and / or VAD can be used to ensure proper positioning of the MCS device and / or VAD relative to the guidewire and / or patient's anatomy).

[0043] As shown in FIG. 1B, in some embodiments, the MCS system 10 may include a low-profile axial rotary blood pump 22 attached to a catheter 16, such as an 8 French size (Fr) catheter, or a catheter of about 10.5 Fr or less. In some embodiments, an inlet tube 70 of the pump 22 extends across an aortic valve 91. An impeller is located in an outflow section 68 (also referred to herein as a pump outlet) of the inlet tube 70, and may draw blood from the left ventricle 93 through the inlet tube 70 and eject it from the outflow section 68 into the ascending aorta 95. A motor may be mounted directly proximal to the impeller in a sealed housing, eliminating the need to purge or flush the motor before or during use. This configuration provides hemodynamic support during high-risk PCI with sufficient time and safety for complete revascularization via a minimally invasive approach (rather than open surgery). The MCS system 10, or portions thereof, may be visualized under fluoroscopy, eliminating the need for placement using sensors. Also shown in Figure 1B are first radiopaque marker 151, second radiopaque marker 152, and third radiopaque marker 153 of guidewire 100 after MCS system 10 has been positioned in a desired location over guidewire 100. The position of guidewire 100 within entrance tube 70 is shown by the dashed line in Figure 1B.

[0044] In some embodiments, the MCS system 10 actively relieves left ventricular strain by pumping blood from the ventricle into the ascending aorta and systemic circulation. When in place, the MCS device can provide 0.4 l / min to up to 6.0 l / min of partial left ventricular support at approximately 60 mmHg pressure differential, driven by a complementary MCS controller 1000. In some embodiments, the MCS system 10 can include a 14 Fr to 18 Fr, or 13 Fr to 19 Fr axial rotary blood pump and inlet tube assembly mounted on the catheter 16.

[0045] In general, the overall MCS system 10 may include a series of associated subsystems and accessories, including one or more of the following: The MCS system 10 may include a pump, shaft, proximal hub, insertion tool, proximal cable, infection shield, guide tube for guidewire and / or guidewire aid. The pump 22 may be provided in a sterile condition. The MCS catheter 16 may include an electrical cable and a guidewire lumen for over-the-wire insertion. The proximal hub may include a guidewire outlet with a valve to maintain hemostasis, and the MCS catheter 16 may be connected to a proximal cable that connects the pump 22 to the controller 1000. The proximal cable 28 may be 3.5 m (about 177 inches) or about 3.5 m long and may extend from the sterile field to a non-sterile field where the controller 1000 is located. The MCS insertion tool may be provided pre-mounted on the MCS device to facilitate insertion of the pump into the introducer sheath and to protect the inlet tube and valve from potential damage or interference as it passes through the introducer sheath. A peel-away guidewire aid may be pre-mounted on the MCS device to facilitate insertion of a placement guidewire, such as the guidewires described herein, into the pump 22 and into the MCS catheter 16, and optionally the MCS insertion tool is also pre-mounted so that the guidewire's guide tube can pass at least partially through the space between the MCS device and the MCS insertion tool. A 3m or about 3m long, 0.018 inch diameter placement guidewire, or any guidewire described herein, with a soft coiled pre-shaped tip for atraumatic wire placement into the left ventricle may be used. The guidewire may be provided sterile. A 14Fr or 16Fr introducer sheath may be used in a usable length of 275mm to maintain access to the femoral artery and provide hemostasis for the first guidewire (e.g., 0.035 inch diameter), diagnostic catheter, 0.018 inch placement guidewire, or any guidewire described herein, and insertion tool. The housing of the introducer sheath may be designed to accommodate the MCS insertion tool. The introducer sheath may be provided sterile.The introducer dilator may be compatible with the introducer sheath to facilitate atraumatic insertion of the introducer sheath into the femoral artery. The introducer dilator may be provided sterile. A controller 1000 may be used to drive and operate the pump 22, monitor its performance and condition, and / or provide error and status information. The powered controller 1000 may be designed to support at least about 12 hours of continuous operation and may include a basic interface to indicate and adjust the level of support provided to the patient. Additionally, the controller 1000 may provide optical and audible alarm notifications if the system detects an error during operation. The controller 1000 may be provided non-sterile and may be contained within an enclosure designed for cleaning and reuse outside of the sterile field. The controller 1000 enclosure may include a socket into which an extension cable may be plugged.

[0046] Referring to Figure 3, an overall MCS system 10 is illustrated in accordance with some embodiments. For reference, the arrows in Figure 3 and elsewhere herein indicate "distal" and "proximal" directions. As used herein, "distal" and "proximal" have their ordinary and customary meanings, including but not limited to directions further from an entry point into the patient's body as measured along a delivery path, and directions not farther from an entry point into the patient's body as measured away along a delivery path, respectively.

[0047] The MCS system 10 may include an introducer sheath 19 having a proximal introducer hub 14 having a central lumen for axially movably receiving an MCS catheter 16 (the MCS catheter 16 may also be referred to herein as a catheter, a catheter shaft, and / or a shaft). The catheter 16 may extend between a proximal hub 18 and a pump 22 of the system 10, with a guidewire 100 extending therethrough. In some embodiments, an atraumatic cannula tip with a radiopaque material allows visualization of the implantation / explantation under fluoroscopy.

[0048] The pump 22 comprises a tubular housing. The term tubular housing of the pump 22 is used broadly herein and may include any component of the pump 22 or components within the pump region of the system, such as the inlet tube, the distal end, the motor housing 12, other connecting tubular structures, and / or the proximal rear end of the motor housing. The pump 22, e.g., the tubular housing, is carried by the distal region of the catheter 16. The system 10 comprises at least one central lumen for axially movably receiving the guidewire 100. The proximal hub 18 additionally comprises an infection shield 26. A proximal cable 28 extends between the proximal hub 18 and a connector 30 for releasable connection to a control system, typically outside the sterile field, to drive the pump 22.

[0049] In some embodiments, the guidewire or a portion of the guidewire may have a diameter of 0.018 inches or about 0.018 inches. In some embodiments, the diameter of the guidewire may be different at different portions of the guidewire, e.g., the proximal and / or distal ends. Unless otherwise stated, all measurements (e.g., angles, lengths) described for the guidewires herein are taken along the central axis of the guidewire.

[0050] Guidewire 100 may include a distal end or tip that is shaped, sized, and / or otherwise configured to traverse distally through a catheter, e.g., a diagnostic catheter having a gauge of 4Fr to 6Fr. The catheter may include one or more side holes or openings, e.g., for flushing of fluid (e.g., fluoroscopy fluid) into the aorta / left ventricle of the patient. The distal end or tip of guidewire 100 may be shaped, sized, and / or otherwise configured to traverse distally through the catheter and exit the distal end of the catheter without exiting the catheter's side holes.

[0051] Guidewire 100 may include a proximal end 104 that is rounded or otherwise shaped, dimensioned, and / or configured to be received within a distal opening of a guidewire lumen of an MCS device or VAD. In some embodiments, a proximal region 108 extending between proximal end 104 and transition section 107 may be sufficiently soft, yet have sufficient column strength and / or axial stiffness to facilitate movement of guidewire 100 through a non-linear path of a guidewire lumen extending through an MCS or VAD device.

[0052] In some embodiments, the guidewire 100 may be designed for travel along sharp or jagged edges of an MCS device or VAD, for example. In some embodiments, the guidewire may be formed of stainless steel, nitinol, titanium alloys, combinations thereof, and the like. In comparison to guidewires coated with PTFE or other lubricious materials, some embodiments include uncoated guidewires to avoid scratching or scraping the coating when travelling along the edges of an MCS device or VAD.

[0053] In some embodiments, one or more portions of guidewire 100 may include a coil positioned about an inner core or other feature to prevent kinking. In some embodiments, the coil may be formed of Nitinol.

[0054] FIG. 4 illustrates a guidewire 100 having an elongated flexible body 102 extending between a proximal end 104 and a distal end 106. In some embodiments, the guidewire 100 may include multiple segments having different diameters. In some embodiments, the guidewire 100 may include a stepped or tapered transition between adjacent segments having different diameters. In some embodiments, the guidewire 100 may include four segments having different diameters. In some embodiments, the guidewire 100 may include a tapered transition between each of the four segments having different diameters. In an alternative embodiment, the transition between the segment having the largest diameter and the segment having the second largest diameter may be a stepped transition.

[0055] Guidewire 100 may include a proximal region 108. In some embodiments, proximal region 108 or a core of proximal region 108 may have a diameter of 0.18 mm or about 0.18 mm. Proximal region 108 may be configured to thread into and through an MCS device or VAD. In some embodiments, proximal region 108 may be sufficiently soft, yet have sufficient column strength and / or axial stiffness, for example, to facilitate movement of guidewire 100 relative to a guidewire lumen of an MCS device or VAD.

[0056] As shown in FIG. 11A, in some embodiments, body 102 of guidewire 100 includes body region 111. Body region 111 may be positioned distal to proximal region 108. In some embodiments, body region 111 or the core of body region 111 may have a diameter of 0.47 mm or about 0.47 mm. In some embodiments, body region 111 may be the least flexible region of guidewire 100. In some embodiments, body region 111 forms the majority of the length of guidewire 100. In some embodiments, body region 111 is configured to transmit forces (e.g., axial forces) applied when handling guidewire 100. In some embodiments, body region 111 may be configured to facilitate passing an MCS device or VAD through body region 111 during delivery to the heart.

[0057] 11A, in some embodiments, body 102 includes pump region 113. In some embodiments, pump region 113 may be positioned distal to body region 111. In some embodiments, pump region 113 or a core of pump region 113 may have a diameter of 0.28 mm or about 0.28 mm. In some embodiments, pump region 113 is configured to be positioned within the MCS device or VAD when the MCS device or VAD is within the heart. In some embodiments, pump region 113 is less stiff than body region 111, for example, to more easily traverse bends in the vasculature.

[0058] Guidewire 100 may also include a distal region 110. Distal region 110 may be positioned distal to pump region 113. In some embodiments, distal region 110 or the core of distal region 110 may have a diameter of at or about 0.13 mm to at or about 0.18 mm, or a diameter of at or about 0.14 mm. In some embodiments, distal region 110 may be the most flexible region of guidewire 100. In some embodiments, distal region 110 may be sufficiently flexible to be atraumatic. In some embodiments, guidewire 100 may be flexible enough to straighten out when withdrawn from the MCS device or VAD or catheter shaft, but may form a pre-curved and / or pre-bent shape when unconstrained (e.g., guidewire 100 may be elastic).

[0059] In some embodiments, the elastic section modulus of guidewire 100 may be defined by the following equation:

number

[0060] "S" is the elastic section modulus and "d" is the diameter. For example, in some embodiments, the section modulus S of at least a portion of the proximal region 108 having a diameter of 0.18 mm or about 0.18 mm is 0.00057 mm 3 or approximately 0.00057 mm 3 In some embodiments, the section modulus S of the proximal region 108 may be 0.0005 mm 3 or about 0.0005mm 3 ~0.0006mm 3 or about 0.0006mm 3 In some embodiments, the section modulus S of at least a portion of the body region 111 having a diameter of 0.47 mm or about 0.47 mm can be 0.0102 mm or less. 3 or about 0.0102 mm 3 In some embodiments, the section modulus of the body region 111 may be 0.0097 mm 3 or about 0.0097 mm 3 ~0.0107mm 3 or about 0.0107 mm 3 In some embodiments, the section modulus S of at least a portion of the pump region 113 having a diameter of 0.28 mm or about 0.28 mm may be 0.00216 mm. 3 or approximately 0.00216 mm 3 In some embodiments, the section modulus of the pump region 113 may be 0.0020 mm 3 or about 0.0020mm 3 ~0.0023mm 3 or about 0.0023 mm 3 In some embodiments, the section modulus S of at least a portion of the distal region 110 having a diameter of 0.14 mm or about 0.14 mm can be 0.000269 mm. 3 or approximately 0.000269mm 3 In some embodiments, the section modulus S of at least a portion of the distal region 110 having a diameter of at or about 0.13 mm to at or about 0.18 mm can be 0.000216 mm. 3 or approximately 0.000216 mm 3~0.000573mm 3 or approximately 0.000573 mm 3 In some embodiments, the section modulus S of the distal region 110 can be 0.00026 mm 3 or approximately 0.00026mm 3 ~0.00028mm 3 or approximately 0.00028mm 3 It can be said that:

[0061] In some embodiments, the proximal region 108 may be more flexible than other regions of the guidewire 100, for example, by virtue of a smaller diameter and / or different chamfers and tapers. In some embodiments, the proximal region 108 may be sufficiently flexible to pass through a guidewire port of an MCS device or VAD having a radius of curvature in the range of about 5 mm to about 25 mm, and in some embodiments, in the range of about 10 mm to about 18 mm. In some embodiments, the proximal region 108 may be sufficiently flexible to pass through a guidewire port of an MCS device or VAD having a radius of curvature as small as about 5 mm, or as small as about 10 mm. The length of the proximal region 108 between the proximal end 104 and the transition portion 107 may be in the range of 50 mm, or about 50 mm to 500 mm, or about 500 mm, in the range of 60 mm, or about 60 mm to 300 mm, or about 300 mm, and in some embodiments, in the range of 285 mm, or about 285 mm to 295 mm, or about 295 mm. The transition region 108 may be a transition between the proximal region 108 and the body region 111 .

[0062] The distal region 110 extending between the distal end 106 and the transition section 109 may be pre-shaped as a pigtail to provide an atraumatic distal surface. The transition section 109 may be a transition between the distal region 110 and the pump region 113. Figures 5A-5C illustrate different embodiments of pigtail configurations of the distal region 110. The pigtail configurations include a spiral coil shape in one plane or substantially in one plane with a coil angle extending from at or about 360° to at or about 1080°. For example, the coil angle may be at or about 360° (shown in Figure 5A), at or about 720° (shown in Figure 5B), or at or about 1080° (shown in Figure 5C). In some embodiments, the spiral coil shape may be defined by a section of the distal region 110 that is spiral shaped. In some embodiments, the spiral coil shape may include curves wound around a center point at continuously increasing distances from the center point or continuously decreasing distances toward the center point. In some embodiments, the spiral coil shape may include successive curves and expanding curves extending from and around the center point, or successive curves and tightening curves extending toward and around the center point. In some embodiments, the spiral coil shape may include multiple loops with different diameters. All of the coils of the spiral coil may lie in a plane or substantially in a plane.

[0063] 6A-6B show an embodiment of a distal region 110 including a distal advancement segment 112a. The advancement segment 112a may be in the form of an elongated straight tip extending from an inflection point between the proximal end of the advancement segment 112a and a pigtail-configured distal end 114. The elongated advancement segment 112a may be shaped, sized, or otherwise configured to traverse distally through the catheter and exit the distal end of the catheter without exiting through a side hole of the catheter. The elongated advancement segment 112a may have a length of 0.5 mm or about 0.5 mm to 25 mm or about 25 mm, 1 mm or about 1 mm to 25 mm or about 25 mm, or 2 mm or about 2 mm to 25 mm or about 25 mm. The length of the advancement segment 112a may prevent or inhibit the advancement segment 112a from exiting through a side hole of the catheter. In some embodiments, the angle of inflection between the distal end 114 of the pigtail configuration and the elongated advancing segment 112a, in combination with the length of the advancing segment 112a, is small enough to prevent the distal end 106 and / or distal end 142 (as shown in FIG. 6C) of the advancing segment 112a from slipping out of the side hole of the catheter. For example, in some embodiments, the angle of inflection between the distal end 114 of the pigtail configuration and the elongated advancing segment 112a is in the range of at or about 5° to at or about 85°.

[0064] FIG. 6C illustrates an example of a distal advancement segment 112a within a catheter 200. In some embodiments, the catheter 200 may be a 4F or 5F catheter. The catheter 200 may have an inner diameter D of at or about 0.9 mm to at or about 1.2 mm. In some embodiments, the catheter 200 may have an inner diameter D of at or about 1.07 mm, a diameter of at or about 1.19 mm, or any other suitable inner diameter D. The catheter 200 may include a sidewall 202 having one or more side holes 204. The side holes 204 may have a diameter of at or about 0.5 mm to at or about 0.8 mm. In some embodiments, the catheter 200 may have 1 to 16 side holes 204, 4 to 12 side holes 204, or any other suitable range. In some embodiments, the catheter 200 may have 8 side holes 204.

[0065] As described herein, the length L of the advancement segment 112a can prevent or inhibit the elongated advancement segment 112a from slipping out of the side hole 204. For example, the length L of the advancement segment 112a can be greater than the maximum diameter of the side hole 204 to an extent that prevents the distal end 106 of the guidewire 100 and / or the distal end 142 of the advancement segment 112a from slipping out of the side hole 204. As shown in FIG. 6C, the angle between the distal end 114 of the pigtail configuration and the advancing segment 112a may be small enough so that when the inflection point at the proximal end 140 of the advancing segment 112a contacts the side wall 202, the distal end 106 of the guidewire 100 and / or the distal end 142 of the advancing segment 112a may be located at or near the radial center of the catheter 200 and / or at an angle relative to the plane of the side hole that prevents the distal end 106 of the guidewire 100 and / or the distal end 142 of the advancing segment 112a from entering the side hole 204.

[0066] The length L of the advancement segment 112a and the angle at the inflection point where the advancement segment 112a extends from the distal end 114 of the pigtail configuration can thus be sized such that only a portion D2 of the diameter of the distal end 106 can extend into one of the side holes 204. The portion D2 can be less than or about half the diameter of the distal end 106 such that contacting the distal end 106 with an edge of one of the side holes 204 while the portion D2 is within the side hole 204 will cause the distal end 106 to deflect into the catheter 200 and not become dislodged from or stuck within the side hole 204. In some embodiments, the portion D2 can be less than or about 1 / 3 or less than or about 1 / 4 of the diameter of the distal end 106. In some embodiments, the diameter portion D2 can be less than or about 0.1524 mm, or less than or about 0.1143 mm. In some embodiments, the diameter portion D2 can be within a range of 0.05 mm or about 0.05 mm to 0.23 mm or about 0.23 mm, 0.1 mm or about 0.1 mm to 0.18 mm or about 0.18 mm, 0.1 mm or about 0.1 mm to 0.16 mm or about 0.16 mm, 0.15 mm or about 0.15 mm to 0.23 mm or about 0.23 mm, or any other suitable range. In some embodiments, the minimum length L of the advancing segment 112a can be within a range of 0.5 mm or about 0.5 mm to 3.5 mm or about 3.5 mm, or 1.58 mm or about 1.58 mm to 3.318 mm or about 3.318 mm. In some embodiments, guidewire 100 can be configured such that the angle θ between the central axis of advancement segment 112a and the longitudinal axis of the catheter can have a maximum value of 17° or within a range of about 17° to 25° or about 25°.

[0067] The distal end 106 of the guidewire 100 and / or the distal end 142 of the advancement segment 112a may have a rounded shape. For example, the distal end 106 and / or the distal end 142 may be hemispherical, hemispherical, parabolic, or otherwise convex. The rounded shape of the distal end 106 and / or the distal end 142 may cause the distal end 106 and / or the distal end 142 to curl or deflect away from an edge of one of the side holes 204 when the distal end 106 and / or the distal end 142 contacts such edge of one of the side holes 204.

[0068] 7A-7B show an embodiment of a distal region 110 that includes a curved advancement segment 112b. The advancement segment 112b may be in the form of a curved or S-shaped segment that extends from an inflection point at the distal end 114 of a pigtail configuration. The advancement segment 112b may be shaped, sized, or otherwise configured to traverse distally through the catheter and exit the distal end of the catheter without exiting through a side hole in the catheter. In the illustrated implementation, the pigtail configuration is concave in a first direction that terminates in a transition with the curved advancement segment 112b, which is concave in a second, opposite direction. This curvature may reduce the risk of scratching and reduce friction as the guidewire is traversed through the catheter and / or guidewire lumen.

[0069] FIG. 7C shows an example of an embodiment of a distal region 110 having a curved advancement segment 112b, showing example dimensions for a portion of the distal region 110. In some embodiments, the length i of the portion of the distal region 110 can be at or about 79 mm. The diameter ii can be at or about 30 mm. The diameter iii can be at or about 26 mm. The diameter iv can be at or about 20 mm. The diameter v can be at or about 7 mm. The pigtail region, if straight, can have a length of at or about 115 mm, at or about 160 mm, at or about 210 mm, at or about 100 mm to at or about 175 mm, at or about 100 mm to at or about 225 mm, or any other suitable length.

[0070] In some embodiments, the curved / bent advancing segment 112b may have a length vi of 1.0 mm, about 1.0 mm, 0.5 mm, about 0.5 mm, 1.5 mm, about 1.5 mm, or between 0.5 mm and 1.5 mm. The curved / bent advancing segment 112b may be angled at an angle vii of 10°, about 10°, 15°, about 15°, 20°, about 20°, 25°, about 25°, 30°, about 30°, 60°, about 60°, 10° or about 10° to 60° or about 60°, 15° or about 15° to 60° or about 60°, or any other suitable angle or range of angles relative to a tangent to the distal end 114 of the pigtail configuration. The length vi (e.g., a length of 1.0 mm) and angle vii (e.g., an angle of 10° or about 10° to 60° or about 60°) may prevent the distal end 106 of the guidewire 100 and / or the distal end 142 of the advancement segment 112b from contacting the sidewall of the catheter when the inflection point or the area around the inflection point contacts the sidewall of the catheter 202 during the guidewire 100 traverse through the catheter 200, e.g., as described in connection with FIG. 7D. In some embodiments, the length vi (e.g., a length of 1.0 mm or about 1.0 mm) and angle vii (e.g., an angle of 10° or about 10° to 60° or about 60°) may space the distal end 106 and / or the distal end 142 from the inner surface of the central lumen, such as near the radial center of the catheter 200, when the inflection point or the area around the inflection point contacts the sidewall 202 of the catheter 200.

[0071] FIG. 7D illustrates an example of an advancement segment 112b within a catheter 200. As shown in FIG. 7D, the advancement segment 112b can be S-shaped with a first curved region 118a having an inflection point 146a and a second curved region 118b having an inflection point 146b. In some embodiments, the curved regions 118a and / or 118b can have an arc length greater than a diameter of the side hole 204 to prevent or limit the advancement segment 112b from slipping out of the side hole 204. In some embodiments, the arc length can be greater than or about 0.5 mm, or greater than or about 0.8 mm. In some embodiments, the arc length can be within a range of 0.5 mm to 1.5 mm or about 1.5 mm, or within a range of 0.8 mm to 1.5 mm or about 1.5 mm. In some embodiments, inflection point 146a and / or inflection point 146b can be configured to contact and / or slide along sidewall 202 as guidewire 100 traverses through catheter 200.

[0072] A portion of the advancing segment 112b may extend from the inflection point 146b at an angle and over a length that prevents the distal end 106 of the guidewire 100 and / or the distal end 142 of the advancing segment 112b from contacting the sidewall 202 while the guidewire traverses through the catheter 200. For example, the curvature and length of the section of the advancing segment 112b extending from the inflection point 146b can position the distal end 106 of the guidewire 100 and / or the distal end 142 of the advancing segment 112b at or near the radial center of the catheter 200 when the inflection point 146b or the area around the inflection point 146b contacts the sidewall 202. By positioning the distal end 106 and / or the distal end 142 at or adjacent to the radial center, the curved shape of the advancing segment 112b can prevent or limit the advancing segment 112b from slipping out of the side hole 204. In some embodiments, the catheter 100 may be configured such that a portion of the advancing segment 112b may extend from the inflection point 146b at an angle θ2 between a central axis of the portion of the advancing segment 112b and a longitudinal axis of the catheter 200. The angle θ2 may have a maximum value in a range of at or about 5° to at or about 85°, or at or about 30° to at or about 60°. In some embodiments, the portion of the advancing segment 112b may extend from the inflection point 146b over a length L2 measured along a central axis of the portion of the advancing segment 112b. The length L2 may be in a range of at or about 0.3 mm to at or about 4 mm, at or about 0.3 mm to at or about 1.5 mm, or at or about 1 mm to at or about 4 mm. The curvature of, and the distance between, inflection points 146a and 146b can cause one or both of inflection points 146a and 146b to contact opposing sidewalls 202 of catheter 200. In some embodiments, the radius of curvature at at least one or both of inflection points 146a and 146b can be greater than the radius of side hole 204. For example, in some embodiments, the radius of curvature at inflection points 146a and 146b can be in the range of at or about 0.5 mm to at or about 0.8 mm.In some embodiments, curved region 118a may be defined by an angle α extending between a central axis of curved region 118a proximal to inflection point 146a and a central axis of curved region 118a distal to inflection point 146a. In some embodiments, angle α may be within a range of at or about 10° to 70° or about 170°, or at or about 60° to 120° or about 120°. In some embodiments, length L3 taken along the central axis of the segment between inflection point 146a and inflection point 146b has a minimum value defined by the following formula:

number

[0073] L3min can be the length that brings inflection points 146a and 146b into contact with sidewall 202 of catheter 200 when catheter 200 has a diameter of 0.9 mm or approximately 0.9 mm.

[0074] In some embodiments, the length L3 may have a maximum value defined by the following formula:

number

[0075] L3max ​​can be the length that brings inflection points 146a and 146b into contact with sidewall 202 of catheter 200 when catheter 200 has a diameter of 1.2 mm or approximately 1.2 mm.

[0076] In embodiments where angle α is at or about 140°, length L3 can range from at or about 1.257 mm to at or about 2.13 mm. In some embodiments, angle θ2 between the central axis of the segment between inflection points 146a and 146b and the longitudinal axis of the catheter can range from at or about 5° to at or about 85°, or from at or about 30° to at or about 60°. In some embodiments, when length L2 is less than length L3 and angle θ2 has the same or approximately the same magnitude as angle θ3, distal end 106 and / or distal end 142 do not extend to the opposing side wall 202, preventing or restricting distal end 106 and / or distal end 142 from slipping out of side hole 204.

[0077] The distal end 106 of the guidewire 100 and / or the distal end 142 of the advancement segment 112b may have a rounded shape. For example, the distal end 106 and / or the distal end 142 may be hemispherical, hemispherical, parabolic, or otherwise convex. The rounded shape of the distal end 106 and / or the distal end 142 may cause the distal end 106 and / or the distal end 142 to curl or deflect away from an edge of one of the side holes 204 when the distal end 106 and / or the distal end 142 contacts such edge of one of the side holes 204.

[0078] FIG. 8A illustrates an embodiment of a distal region 110 in which the distal end 106 includes a distal advancing segment 112c in the form of an enlarged distal tip. The advancing segment 112c can be shaped, sized, or otherwise configured to traverse distally through the catheter and exit the distal end of the catheter without exiting through a side hole in the catheter. The advancing segment 112c can have a diameter D3 that is larger than a portion of the pigtail region immediately proximal to the advancing segment 112c. For example, the advancing segment 112c or the largest cross section of the advancing segment 112c can have a diameter D3 of 0.8 mm or about 0.8 mm to 1 mm or about 1 mm. In some embodiments, the advancing segment 112c can be spherical or spheroidal in shape, for example, as shown in FIG. 8A.

[0079] 8B illustrates an example of an advancing segment 112c having an enlarged distal tip within catheter 200. In some embodiments, the diameter of the advancing segment at its largest cross section may be equal to or greater than the diameter of side hole 204 to prevent advancing segment 112c from slipping out of side hole 204. As discussed above, the diameter of the advancing segment at its largest cross section may be at or about 0.8 mm to at or about 1 mm, and the diameter of side hole 204 may be at or about 0.5 mm to at or about 0.5 mm to at or about 0.8 mm.

[0080] 8B, in some embodiments, the distal end 106 of the guidewire 100 and / or the distal end 142 of the advancement segment 112c may have a rounded shape that tapers proximally over a tapered portion 141 from the distal end 106 and / or the distal end 142 to the proximal end 140 of the advancement segment 112c. The distal end 106 and / or the distal end 142 may be hemispherical, hemispherical, parabolic, or otherwise convex. The rounded shape of the distal end 106 and / or the distal end 142 may cause the distal end 106 to curl or deflect away from an edge of one of the side holes 204 when the distal end 106 and / or the distal end 142 contacts such edge of one of the side holes 204. In some embodiments, the tapered shape of tapered portion 141 can prevent the guidewire from catching on the edges of the catheter / entry tube of the MCS device and / or VAD when being removed therefrom.

[0081] 9A-9B illustrate an embodiment of a portion of distal region 110. In some embodiments, distal region 110 and / or at least a portion of elongated flexible body 102 may include core 120 and a coil 122 of thin wire surrounding core 120. Coil 122 may help prevent guidewire 100 from kinking. As shown in FIGS. 9A-9B, core 120 may include segments 120a and 120c having different diameters. In some embodiments, the diameter of core 120 may be 0.10 mm or about 0.10 mm to 0.5 mm or about 0.5 mm. In some embodiments, the diameter of core 120 may be 0.13 mm or about 0.13 mm to 0.18 mm or about 0.18 mm. In some embodiments, the diameter of core 120 may be 0.43 mm or about 0.43 mm to 0.5 mm or about 0.5 mm. In some embodiments, the maximum diameter of guidewire 100 can be at or about 0.5 mm, for example, to allow for the use of catheters no larger than 10 Fr.

[0082] Segments 120a and 120c may be connected by a tapered or chamfered transition segment 120b. The different diameters and tapered or chamfered segments may provide different levels of flexibility between the different segments. For example, segment 120a located distal to segment 120c may have increased flexibility compared to segment 120c due to its smaller diameter and tapered or chamfered connection. In this manner, distal region 110 and / or distal end 106 may be more flexible than more proximal portions of guidewire 100.

[0083] In some embodiments, the coil 122 may be soldered to the core 120 using solder 124. FIG. 9A illustrates the coil 122 extending over the segment 120a, the tapered or chamfered transition segment 120b, and the segment 120c. The coil 122 is soldered to the segment 120c in FIG. 9A. As shown in FIG. 9A, the solder 124 may be in the form of a chamfer to provide a smooth transition. By extending across the transition segment 120b, the arrangement of the coil 122 shown in FIG. 9A may prevent kinking at the transition segment 120b. Such an arrangement may allow for a smaller diameter segment 120a with increased softness and / or flexibility. In FIG. 9B, the coil extends over the segment 120a and is soldered to the tapered transition segment 120b. As shown in FIG. 9B, the coil 122 has the same or nearly the same outer diameter as the segment 120c. Solder 124 may be applied such that the outer diameter of segment 120c, coil 122, and solder 124 have a continuous or substantially continuous smooth outer diameter. This arrangement avoids edges that may get caught during movement of guidewire 100. In other embodiments, coil 122 may be glued, welded, or otherwise adhered to core 120.

[0084] Although Figures 9A-9B show distal region 110, the use of coils and / or tapered or chamfered segments to affect the flexibility of different regions of guidewire 100 may also be used in at least portions of other regions, such as, for example, proximal region 108, body region 111, and / or pump region 113, as shown in Figures 10A-10B.

[0085] 10A-10B illustrate an embodiment of a guidewire 100. As shown in FIGS. 10A-10B, the proximal end 104 and the distal end 106 may include rounded edges. The rounded edges of the distal end 106 may provide for atraumatic movement of the distal end 106 within the anatomy. The rounded edges of the proximal end 104 may facilitate insertion of the proximal end 104 into the MCS device and / or VAD and their respective catheters 16. The rounded (e.g., hemispherical) shape of the distal end 106 and / or the proximal end 104 may be formed by forming, machining, welding, and / or melting the core 120 and, optionally, the coil 122. Alternatively, the core 120 and, optionally, the coil 122 may be soldered to form the rounded distal end 106. Alternatively, a bead of adhesive can be used to form the rounded ends and adhere to the core 120 and, optionally, the coil 122 .

[0086] As shown in FIGS. 10A-10B, the guidewire 100 may include a coil 122 surrounding the core 120 at the proximal and / or distal regions 108, 110. The core 120 at the proximal and / or distal regions may have a smaller diameter than the core 120 at a more central region of the guidewire 100. For example, in FIG. 10B, the diameter of the core 120 may be about 0.18 mm at the proximal and distal ends 104, 106, but about 0.457 mm at the central region of the guidewire. The smaller diameter at the proximal and / or distal ends 104, 106 may provide increased flexibility at the proximal and / or distal ends 104, 106. The coil 122 may prevent kinking in those regions having a smaller diameter. As shown in FIGS. 10A-10B, in some embodiments, the coil 122 may be bonded to the core 120.

[0087] In some embodiments, the distal region 110 can be radiopaque along its entire length, such as with individual multiple markers or continuous markers. For example, the individual radiopaque markers can include gold solder at the distal tip 106, gold solder 124 connecting the coil 122 to the core 120, and / or multiple radiopaque spots spaced (e.g., evenly spaced) along the length of the distal region 110. Alternatively, or additionally, at least a portion of the guidewire 100 (e.g., the distal region 110 or at least a portion thereof) can have a polymer coating doped with barium sulfate or another radiopaque material. In some embodiments, the coil 122 of the distal region 110 can be made from a radiopaque material or metal, such as platinum, gold, iridium, or a combination thereof. In use, the radiopaque distal region 110 can be seen under fluoroscopy without the need to inject a contrast agent. This may advantageously facilitate ease and safety of use by allowing the physician / user to visualize and confirm that the distal region 110 is properly positioned within the patient's cardiovascular system (e.g., left ventricle) or if it has become dislodged and requires attention for repositioning. Additionally, this may also help prevent entanglement of the guidewire 100 with anatomical structures or other medical components in the vicinity of the guidewire 100. In other embodiments, the distal region 110 may be radiopaque along a portion of its length. For example, the distal region 110 may be radiopaque along the advancing segment or at least a portion of the advancing segment.

[0088] In some embodiments, the core 120 may include one or more stepped transitions 128 between adjacent segments having different diameters. As shown in FIG. 10B, in some embodiments, the coil 122 may be wound around a segment(s) of the core 120 having a smaller diameter and abut the stepped transition to reduce or prevent the guidewire 100 from having sharp edges that could snag or scratch other components. The core 120 may also include one or more tapered or chamfered transition segments, which may be conical or frustoconical, between adjacent segments having different diameters. For example, the guidewire 100 may include a conical or frustoconical transition segment 134 in the distal portion 110 and / or a conical or frustoconical transition segment 136 in or adjacent the proximal portion 108.

[0089] As shown in FIGS. 10A-10B, the overall length L4 of guidewire 100 (not including rounded proximal end 104 and distal end 106) may be 3000 mm±30 mm or about 3000 mm±30 mm. The length L5 of distal region 110 of guidewire 100 may be 135 mm±35 mm or about 135 mm±35 mm, at least a portion of which may be configured as a pigtail as described herein beginning at point 132 along length L5. The length L6 of central region 100 may be 2600 mm±300 mm or about 2600 mm±300 mm. The length L7 of proximal region 108 of guidewire 100 may be 328 mm±50 mm or about 328 mm±50 mm.

[0090] 11A-11C illustrate another embodiment of guidewire 100. As described with respect to FIGs. 10A-10B, proximal region 108 and / or distal region 110 of core 120 may have a smaller diameter than a central region of guidewire 100 to enhance flexibility. Proximal region 108 and / or distal region 110 may include a coil 122 surrounding core 120 to prevent kinking.

[0091] As shown in Figure 11A, guidewire 100 may include one or more tapered segments to transition between segments having different diameters. As shown in Figures 11B-11C, in some embodiments, coil 122 may be attached to core 120 using solder 124. In some embodiments, solder 124 may provide a smooth transition between coil 122 and adjacent segments to reduce or prevent sharp edges.

[0092] 11A, the overall length L8 of guidewire 100 can be at or about 3000 mm ± 20 mm. The length L9 of distal region 110 of guidewire 100 can be at or about 38 mm ± 3 mm and can have a diameter D4 of at or about 0.130 mm ± 0.004 mm, 0.180 mm ± 0.004 mm, or 0.130 mm ± 0.004 mm to 0.180 mm ± 0.004 mm or about 0.180 mm ± 0.004 mm. Length L11 proximal to length L9 may be 30 mm±3 mm or about 30 mm±3 mm and may have a diameter D5 of 0.237±0.004 mm or about 0.237±0.004 mm. Length L10 of guidewire 100 between lengths L9 and L11 may be tapered over its length of 20 mm±3 mm or about 20 mm±3 mm, transitioning from diameter D4 at its distal end to diameter D5 at its proximal end. Length L13 of pump region 113 of guidewire 100 may be 35 mm±3 mm or about 35 mm±3 mm and may have a diameter D6 of 0.280±0.004 mm or about 0.280±0.004 mm. Length L12 of guidewire 100 between lengths L11 and L13 can be tapered over its length of 30 mm±3 mm or about 30 mm±3 mm, transitioning from a diameter D5 at its distal end to a diameter D6 at its proximal end. Length L15 of body region 111 of guidewire 100 can be 2427 mm±20 mm or about 2427 mm±20 mm, and can have a diameter D7 of 0.470 mm±0.005 mm or about 0.470 mm±0.005 mm. Length L14 of guidewire 100 between lengths L13 and L15 can be tapered over its length of 50 mm±3 mm or about 50 mm±3 mm, transitioning from a diameter D6 at its distal end to a diameter D7 at its proximal end. The proximal region 108 of guidewire 100 may have a length L17 of at or about 40 mm±3 mm and a diameter D8 of at or about 0.130 mm±0.004 mm.A length L16 of guidewire 100 between lengths L15 and L17 may be tapered over its length of 330 mm±6 mm or about 330 mm±6 mm, transitioning from a diameter D7 at its distal end to a diameter D8 at its proximal end. In some embodiments, coil 122 may be attached to core 120 and extend distally from distal end 106 a length L18 of 160 mm±5 mm or about 160 mm±5 mm. In some embodiments, coil 122 may be attached to core 120 and extend proximally from proximal end 104 a length L19 of 300 mm±5 mm or about 300 mm±5 mm. In some embodiments, length L16 may include a tapered section at its distal end having a length of 80 mm ± 3 mm or about 80 mm ± 3 mm transitioning from diameter D7 to a diameter of 0.241 mm ± 0.004 mm or about 0.241 mm ± 0.004 mm, and a tapered section at its proximal end having a length of 250 mm ± 3 mm or about 250 mm ± 3 mm transitioning from a diameter of 0.241 mm ± 0.004 mm or about 0.241 mm ± 0.004 mm to diameter D8.

[0093] As shown in FIG. 11B, the elongated flexible body 102 may include one or more markers 130. In some embodiments, the marker(s) 130 may be radiopaque markers. In some embodiments, the marker(s) 130 may be visually identifiable when viewing the guidewire 100 (e.g., by the naked eye without fluoroscopy) and may include metal bands, inks, heat shrink, etching, polishing, soldering, and / or welded metal layers. The marker(s) 130 may be positioned 15 mm or about 15 mm distal from the coil end points of adjacent coils 122. The marker(s) 130 may be 1 mm or about 1 mm wide and spaced apart at intervals of 2 mm or about 2 mm, although other dimensions are considered within the scope of the present disclosure. In some embodiments, as shown in FIG. 11B, the guidewire 100 may include three markers 130, although any number of markers 130 may be included. 11B , in certain embodiments, one or more markers 130 may be positioned anywhere along the guidewire 100. In certain embodiments, the guidewire 100 may include markers 130 positioned on multiple different segments of the guidewire 100. For example, the guidewire may include a first marker 130 or a first plurality of markers 130 on a first segment of the guidewire 100 and a second marker 130 or a second plurality of markers 130 on a second segment of the guidewire 100.

[0094] The marker(s) 130 may be positioned such that, when aligned with the additional reference point while advancing the guidewire 100 into the MCS device or VAD, it provides an indication to the user that the guidewire 100 has advanced sufficiently far within the MCS device or VAD. For example, as described in connection with FIG. 16, a removable guidewire assist 38 may be used with the MCS device or VAD to assist in positioning the guidewire 100 therein. The marker(s) 130 may be positioned such that they align with the distal end of the guidewire assist 38 to indicate that the guidewire 100 has advanced sufficiently far to be secured within the MCS device or VAD (e.g., within the catheter 16) so that the guidewire assist 38 can be removed. In some embodiments, the distance between the marker 130 and the proximal end 104 may be greater than the length of the guidewire assist 38.

[0095] In some embodiments, one or more marker(s) 130 may be positioned on guidewire 100 a distance X from distal end 106 of guidewire 100 such that when distal end 106 is aligned with a guidewire port of the MCS shaft (e.g., third guidewire port 80 described with respect to FIGS. 15-21 ), marker(s) 130 just exit (e.g., are just proximal to) proximal guidewire port 37 of proximal hub 18 of the MCS system (with reference to FIG. 3 ). For example, distance X may be equal to or approximately equal to the distance between the guidewire port of the MCS shaft (e.g., third guidewire port 80 described with respect to FIGS. 15-21 ) and the proximal guidewire port 37 of proximal hub 18 of the MCS system plus an amount Y, where Y may be within a range of 0 mm or about 0 mm to 10 mm or about 10 mm, preferably 2 mm or about 2 mm. In some embodiments, the marker(s) 130 may have an overall length (along the longitudinal axis of the guidewire 100) ranging from at or about 1 mm to at or about 10 mm, preferably at or about 5 mm. In use, the physician / user may have the MCS device through which the guidewire 100 passes such that the distal tip 106 of the guidewire 100 is further distal than the distal guidewire port of the MCS device (e.g., the first guidewire port 76 described in connection with FIG. 16), such as when positioned in the left ventricle 93 as shown in FIG. 1B. If the physician / user desires to retract the guidewire, the guidewire 100 and the proximal hub 18 of the MCS system may both be external to the patient and visible to the physician / user during retraction. When the marker(s) 130 appear to exit the proximal hub 18 (e.g., exiting the proximal guidewire port 37), it can serve as an indication that the distal tip 106 of the guidewire 100 no longer protrudes distally from the MCS device (e.g., the distal tip 106 is within the MCS device, its relief bend 62, see FIG. 16, or its catheter 16).In some embodiments, guidewire 100 may include marker(s) 130, which may be optically distinguishable from one another and may be positioned a distance from distal tip 106 of guidewire 100 such that when distal tip 106 of guidewire 100 is aligned with the various guidewire ports of the MCS system, such as first guidewire port 76, second guidewire port 78, and / or third guidewire port 80 described in connection with FIG. 16 , it is aligned with an exit port of the proximal hub 18 of the MCS system (e.g., proximal guidewire port 37) (and thus visible by the physician / user).

[0096] FIG. 11C illustrates a cross-sectional view of the guidewire of FIG. 11B. As previously discussed, the coil 122 can be soldered to the core 120 using solder 124 (e.g., soldered circumferentially at the longitudinal ends of the coil 122 as shown). Additionally, the coil 122 can have an outer diameter that is the same or nearly the same as the solder 124. To accomplish this, the diameter of the core can be reduced, such as diameter D9 shown in FIG. 11C. For example, the core can have a diameter D9 of 0.270 mm ± 0.004 mm or about 0.270 mm ± 0.004 mm to allow the coil 122 to wrap around it, and an overall diameter of 0.47 mm ± 0.005 mm or about 0.47 mm ± 0.005 mm. The coil 122, when included in the guidewire 100, can have a wire thickness of 0.078 mm or about 0.078 mm to 0.082 mm or about 0.082 mm. In some embodiments, multiple coils 122 may be used with guidewire 100 across different sections or segments of guidewire 100. Additionally, multiple coils 122 may have different wire thicknesses and outer diameters. Coils 122 may be stainless steel, nitinol, or the like, or may be made of a radiopaque material as described herein. In some embodiments, coils 122 may be connected to core 120 using gold solder, which is highly radiopaque.

[0097] 12 illustrates an embodiment of the proximal region 108 of the guidewire 100. The proximal region 108 may include a coil 122 spanning its length extending distally, e.g., at or about 300 mm from the proximal end 104, although the coil 122 is not shown for clarity. As shown, a portion of the guidewire 100 distal to the proximal region may have a diameter D10 of 0.470 mm ± 0.005 mm or about 0.470 mm ± 0.005 mm. The diameter of the guidewire 100 may taper from diameter D10 to diameter D11 of 0.241 mm ± 0.004 mm or about 0.241 mm ± 0.004 mm along a length L20 of 80 mm ± 3 mm or about 80 mm ± 3 mm, as shown. The diameter of guidewire 100 may further taper from diameter D11 to diameter D12 of 0.180 mm±0.004 mm or about 0.180 mm±0.004 mm along a length L21 of 250 mm±3 mm or about 250 mm±3 mm, as shown. The most proximal section of the proximal region may have a diameter D12 along its length L22 of 40 mm±3 mm or about 40 mm±3 mm, as shown.

[0098] 13 illustrates another embodiment of the proximal region 108 of the guidewire 100. The proximal region 108 can include a coil 122 as shown, which can extend distally from the proximal end 104 a length L25 of 108 mm±3 mm or about 108 mm±3 mm. As shown, a portion of the guidewire 100 distal to the proximal region can have a diameter D13 of 0.470 mm±0.005 mm or about 0.470 mm±0.005 mm. The diameter of the guidewire 100 can taper from diameter D13 to diameter D15 of 0.180 mm±0.004 mm or about 0.180 mm±0.004 mm along a length L23 of 220 mm±3 mm or about 220 mm±3 mm, as shown. The proximal most section of the proximal region may have a diameter D15 along its length L24 of, as shown, 40 mm±3 mm or about 40 mm±3 mm. As further shown, coil 122 may terminate distally in a portion of guidewire 100 having a diameter D14 of, as shown, 0.270 mm±0.004 mm or about 0.270 mm±0.004 mm.

[0099] Compared to the embodiment shown in FIG. 12, the embodiment of FIG. 13 may have a reduced level of friction when passing through the MCS device and its catheter 16 due to the reduced coil length. Additionally, the embodiment of FIG. 13 may have an increased ability to transmit longitudinal forces compared to the embodiment of FIG. 12 due to the shorter length of its tapered section. Due to the shorter length of the tapered section, the embodiment of FIG. 13 may be stiffer in the proximal region 108 than the embodiment of FIG. 12 (e.g., for easier insertion), but may have a softer proximal end to reduce friction during insertion. A proximal region 108 lacking sufficient stiffness may result in buckling or reduced force transmission to the proximal end 104 of the guidewire 100 when the proximal end 104 is inserted into the MCS device. In certain embodiments, a diameter of the guidewire 100 greater than or about 0.36 mm may provide sufficient stiffness to facilitate insertion of the guidewire 100 into the MCS device (e.g., by preventing or reducing buckling or reduced force transmission). In certain embodiments, a diameter at the proximal end 104 less than 0.36 mm or about 0.36 mm, such as at or about 0.18 mm, may provide a sufficiently small and soft surface for inserting the proximal end 104 into an MCS device without significant friction. Thus, in certain embodiments, it may be beneficial to have a diameter less than 0.36 mm or about 0.36 mm at the proximal end 104, while having a diameter greater than 0.36 mm or about 0.36 mm sufficiently near the proximal end 104 to prevent or reduce buckling or reduced force transmission. The guidewire 100 of the embodiment of Figure 13 may have a diameter greater than or about 0.36 mm for a length of at or about 176 mm or more from the proximal end 104, while the guidewire 100 of the embodiment of Figure 12 may have a diameter greater than or about 0.36 mm for a length of at or about 331 mm from the proximal end 104. Thus, the guidewire 100 of the embodiment of Figure 13 may provide an increase in stiffness sufficient to prevent or reduce buckling or reduced force transmission at distances closer to the proximal end 104 than the guidewire of the embodiment of Figure 12.

[0100] FIG. 14 illustrates another embodiment of the proximal region 108 of the guidewire 100. The proximal region 108 can include a coil 122 as shown, which can extend distally from the proximal end 104 by a length L30 of 108 mm±3 mm or about 108 mm±3 mm. As shown, a portion of the guidewire 100 distal to the proximal region can have a diameter D16 of 0.470 mm±0.005 mm or about 0.470 mm±0.005 mm. The diameter of the guidewire 100 can taper from diameter D16 to diameter D17 of 0.35 mm or about 0.35 mm to 0.40 mm or about 0.40 mm, preferably 0.360 mm±0.004 mm or about 0.360 mm±0.004 mm, along a length L26 of 20 mm or about 20 mm to 50 mm or about 50 mm, as shown. Guidewire 100 can maintain a diameter D17 along a length L27 of 1000 mm ± 10 mm or about 1000 mm ± 10 mm, as shown. The diameter of guidewire 100 can further taper from diameter D17 to diameter D19 of 0.180 mm ± 0.004 mm or about 0.180 mm ± 0.004 mm along a length L28 of 220 mm ± 3 mm or about 220 mm ± 3 mm, as shown. The most proximal section of the proximal region can have a diameter D19 along its length L29 of 40 mm ± 3 mm or about 40 mm ± 3 mm, as shown. As further shown, coil 122 can terminate distally in a portion of guidewire 100 having a diameter D18 of 0.270 mm ± 0.004 mm or about 0.270 mm ± 0.004 mm. In use, the entire proximal region 108 of guidewire 100, including lengths L31, L27 and L26, may pass through the entire length of the MCS device and its catheter 16 before the MCS device and its catheter are inserted into a patient. Once the proximal end 104 and / or proximal region 108 exits the proximal guidewire port 37 of the proximal hub 18 of the MCS system, it may be retained and advanced across the thicker diameter D16 while advancing the MCS device / catheter into the patient's vasculature.

[0101] Tapered section(s) of guidewire 100, if included, may be made by grinding core 120 of guidewire 100 to a desired profile. Alternatively, or additionally, such section(s) may be made as separate pieces and joined together, such as by welding, soldering, or another mechanical joint.

[0102] In some embodiments, the guidewires described herein may be used in an MCS system or a mechanical left ventricular assist system, for example, for placement of an MCS device or a VAD. Figures 15-21 show the distal region of an embodiment of an MCS device. As shown in Figure 15, a pump zone 60 extends between a bend relief 62 at the distal end of the catheter 16 and a distal tip 64. A pump inlet 66 is in fluid communication with a pump outlet 68 by a flow path extending axially through an inlet tube 70. The pump inlet 66 may be positioned about the transition between the inlet tube 70 and the proximal end of the distal tip 64, and in either case is generally within at or about 5 cm or 3 cm or about 3 cm of a distal port 76. The inlet tube 70 may have an axial length in the range of about 60 mm to about 100 mm, and in one implementation is at or about 67.5 mm. The outer diameter of the inlet tube 70 may be in the range of at or about 4 mm to at or about 5.4 mm, and in one implementation is at or about 4.66 mm.

[0103] The impeller 72 is positioned in the flow path between the pump inlet 66 and the pump outlet 68. In the illustrated embodiment, the impeller 72 is positioned adjacent to the pump outlet 68. As discussed further below, the impeller 72 is driven to rotate by a motor contained within a motor housing 74 on a proximal side of the impeller 72.

[0104] The proximal end 104 of the guidewire 100 described herein may be provided with a rounded end to facilitate entry into the distal opening of the guidewire lumen 84 (shown in FIG. 17). For example, the proximal end 104 may be hemispherical, hemispherical, parabolic, or otherwise convex. With reference to FIG. 16, the proximal end 104 and proximal region 108 may be configured to enter the distal first guidewire port 76 and advance proximally to the second guidewire port 78, where the proximal end 104 exits the MCS device or VAD, extends proximally across the exterior of the impeller 72 and motor housing 74 of the MCS device or VAD, and enters the catheter 16 or bend relief 62 of the MCS device or VAD via the third guidewire port 80. In some embodiments, the distance between the second guidewire port 78 and the third guidewire port 80 can be in the range of at or about 60 mm to at or about 95 mm, in the range of at or about 60 mm to at or about 85 mm, or in the range of at or about 70 mm to at or about 95 mm. The third guidewire port 80 is located proximal to the motor housing 74, and in the illustrated embodiment, is located on the bend relief 62. The third guidewire port 80 extends proximally through the length of the catheter 16 and communicates with a guidewire lumen 84 that exits at the proximal guidewire port 37 of the proximal hub 18 (shown in FIG. 3).

[0105] The catheter 16 may be provided with a removable guidewire guide tube 83 that tracks the intended path of the guidewire from the first guidewire port 76, proximally through the distal tip 64 via the second guidewire port 78, back outside the entrance tube 70, and back into the catheter 16 or bend relief 62 via the third guidewire port 80. In the implementation illustrated in FIG. 16 , the guidewire guide tube 83 extends within the catheter 16 proximal to the proximal end 81, in communication with or within a guidewire lumen 84 that extends to the proximal hub 18. The proximal end 81 of the guidewire guide may be positioned within 5 mm or about 5 mm or about 10 mm or about 10 mm of the distal end of the catheter 16, or may extend into the guidewire lumen 84 at least 10 mm or about 10 mm or about 20 mm, such as within a range of 10 mm or about 10 mm to 50 mm or about 50 mm, or within a range of 30 mm or about 30 mm to 50 mm or about 50 mm, etc. In some embodiments, the guidewire guide tube 83 may have an inner diameter in a range of 0.6 mm or about 0.6 mm to 1 mm or about 1 mm. The proximal end 104 of the guidewire 100 may be inserted into the first (distal) guidewire port 76 and guided along the intended path by tracking the inside of the guidewire guide tube 83. The guidewire guide tube 83 may then be removed leaving the guidewire in place.

[0106] Proximal region 108 of guidewire 100 can therefore be configured to track inside guidewire guide tube 83 at any tight angle necessary to traverse second guidewire port 78 and third guidewire port 80 without kinking and while maintaining a low friction relationship with guidewire lumen 84. Figure 17 is an enlarged cross-sectional view of bend relief 62 and a portion of catheter 16 of the MCS device showing guidewire 100 entering bend relief 62 via third guidewire port 80.

[0107] Guidewire lumen 84 may be defined by guidewire tube 85. Guidewire tube 85 may have an inner diameter of at or about 0.8 mm. Guidewire tube 85 may have an outer diameter of at or about 1.1 mm. In some embodiments, guidewire tube 85 may have a radius of curvature ranging from at or about 10 mm to at or about 18 mm as it bends away from the central axis of catheter 16 toward third guidewire port 80.

[0108] Guidewire tube 85 may be configured to minimize friction therein. In some embodiments, guidewire tube 85 may be formed of PTFE. In some embodiments, guidewire tube 85 may include an outer coating, such as a polyether block amide (PEBA) coating. In some embodiments, guidewire tube 85 may be formed of polyether block amide (PEBA) and may have a lubricious inner lining, such as a PTFE inner lining, to reduce friction therein.

[0109] In some embodiments, as shown in FIG. 16, the guidewire guide tube 83 may be part of a removable guidewire aid 38. The guidewire aid 38 may include a funnel 92 to facilitate insertion of a guidewire into the guidewire port 76. In some embodiments, the distal end of the guidewire guide tube 83 is attached to a pull tab 94 of the guidewire aid 38 and provided with an axially extending split line, such as a weakened line, a slotted line, or a perforated tear line. Removal may be accomplished, such as by grasping the pull tab 94 and withdrawing the guidewire guide tube 83 as the pull tab 94 splits and peels away along the split line. In some embodiments, the inner surface of the guidewire guide tube 83 may be provided with a lubricious coating, such as PTFE.

[0110] 17, at least a portion of guidewire tube 85 may be positioned within tube 86 in catheter 16. Catheter 16 may include additional components in the space between guidewire tube 85 and tube 86, such as conductor wires and / or control wires for operation of the MCS device or VAD.

[0111] Guidewire tube 85 may extend distally beyond the distal end of tube 86 to guidewire port 80. Distal to tube 86, additional components such as conductor wires and / or control wires for operation of an MCS device or VAD may be housed between guidewire tube 85 and the inner surface of bend relief 62.

[0112] As shown in FIGS. 18-19, the bend relief 62 (also referred to as a strain relief) may be a metal tube (e.g., stainless steel or nitinol) with a plurality of helical laser cuts 88. The bend relief 62 may be flexible, but provides increased stiffness at the transition between the motor housing 74 and the catheter 16 compared to the portion of the catheter 16 proximal to the bend relief 62. The stiffness of the bend relief 62 may be greater than the stiffness of the catheter 16 proximal to the bend relief 62 to prevent kinking while being pushed distally, such as when the MCS device or VAD is pushed distally over the guidewire 100.

[0113] In certain embodiments, the helical laser cut 88 may extend along the length of the bend relief 62. The area around the third guidewire port 80 may be free of the laser cut 88. Instead, a solid border 89 may extend around the third guidewire port 80.

[0114] The bend relief 62 may also include an inwardly folded flap 90. The flap 90 may extend from the boundary 89 into the inner lumen of the bend relief 62. The flap 90 of the bend relief 62 may provide support to the guidewire tube 85 to guide the guidewire tube 85 out of the bend relief 62 and to keep the guidewire tube 85 in place. In some embodiments, the guidewire tube 85 may be attached to the flap 90 by an adhesive, such as glue. The flap 90 may provide strength to the guidewire tube 85 and the third guidewire port 80. In some embodiments, the flap 90 may prevent kinking of the guidewire tube 85. In some embodiments, the flap 90 may bend inwardly toward the inner lumen of the bend relief 62 at an angle of at or about 30° to at or about 60°, such as at or about 45°, from the boundary 89.

[0115] In certain embodiments, the guidewire tube 85 may be attached to the boundary 89 by an adhesive, such as glue, in addition to or alternatively to the flap 90. As shown in FIG. 19 , in some embodiments, an adhesive bead or seam 96 may be positioned over the boundary 89 and the cut edge of the guidewire tube 85. The distal end of the guidewire tube 85 may be flush with the boundary 89. The bead 96 may secure the guidewire tube 85 in place. The bead 96 may also prevent scratching between the guidewire 100 and the bend relief 62. For example, the bead 96 may be positioned such that the guidewire 100 contacts the bead 96 as the guidewire 100 moves along the guidewire path.

[0116] 20A-C, in some embodiments, the bend relief 62 can include a laser welded seam 97 around the third guidewire port 80 to form a smooth edge that allows a guidewire 100 to pass through the third guidewire port 80 without catching on the boundary 89. As shown in FIGs. 20A-C, in some embodiments, the third guidewire port 80 can be elliptical, oblong, or generally elliptical or generally oblong in shape.

[0117] As shown in Figure 19, the bend relief 62 can include an inner liner 99a positioned within the metal tube and an outer liner 99b positioned over the metal tube. As shown in Figure 18, holes 98 at the proximal and distal ends of the bend relief 62 can provide a connection between the inner and outer liners. In some embodiments, the inner and outer liners 99a and 99b can be connected to one another through a helical laser cut 88.

[0118] 21 is a perspective view of a portion of the distal region of the MCS device or VAD including the third guidewire port 80 and showing the junctions between the motor housing 74 and the bend relief 62 and between the bend relief 62 and the catheter 16. As shown in FIG. 21, the bend relief 62 can be securely connected to the motor housing 74 by a back end pin 124 inserted through a hole in the bend relief 62 and the motor housing 74, which provides sufficient tensile strength to pull on the catheter 16 to remove or manipulate the MCS device or VAD.

[0119] In some embodiments, a method of delivering a device to a patient's cardiovascular system may be performed using guidewire 100. The method may include delivering an access guidewire to the patient's cardiovascular system having an outer diameter greater than the minimum outer diameter of guidewire 100. For example, the access guidewire may have an outer diameter of 0.035 inches or about 0.035 inches. After delivery of the access guidewire, the method may include advancing a catheter, such as catheter 200, over the access guidewire. As described herein, catheter 200 may include one or more side holes. After catheter 200 is advanced over the access guidewire, the access guidewire may be removed from catheter 200. After the access guidewire is removed from catheter 200, guidewire 100 may be advanced through catheter 200 into the patient's cardiovascular system. As described herein, guidewire 100 may bypass the holes in catheter 200 without extending out of the side holes of catheter 200 as guidewire 100 advances through catheter 200. After the guidewire 100 has been advanced through the catheter 200, the catheter 200 may be removed from the guidewire 100 and the patient. After the catheter 200 has been removed, the proximal end 104 of the guidewire 100 may be delivered to the distal end of a device such as an MCS device (e.g., shown in FIGS. 15-21) or a VAD or heart pump. After the proximal end 104 of the guidewire 100 has been delivered to the distal end of the device, the device may be advanced over the guidewire 100 into the patient's cardiovascular system (e.g., shown in FIG. 1B).

[0120] In some embodiments, a method of delivering a device to a patient's cardiovascular system may be performed using a guidewire 100 including one or more radiopaque markers, such as radiopaque markers 151, 152, and / or 153 described with respect to FIG. 1A. The method may include delivering the guidewire 100 from an access point (e.g., the femoral artery) through a diagnostic catheter, such as a 5Fr catheter or catheter 200 described herein, to position a distal end of the guidewire 100 in the left ventricle. In some embodiments, the positioning of the distal end of the guidewire 100 may be confirmed by visualizing and confirming that the radiopaque markers 151 and / or 152 are located in the left ventricle and the radiopaque marker 153 is located in the aorta. For example, in certain embodiments (e.g., embodiments including all three radiopaque markers 151, 152, and 153, or embodiments including only radiopaque markers 151 and 153), guidewire placement can be confirmed by visualizing and viewing that radiopaque marker 151 is in the left ventricle and radiopaque marker 153 is in the aorta. In certain embodiments, positioning of guidewire 100 can be confirmed by visualizing and viewing that the aortic valve is positioned between radiopaque marker 153 and one or both of radiopaque marker 152 and radiopaque marker 151 (e.g., confirming that the aortic valve is positioned between radiopaque marker 153 and radiopaque marker 152). Contrast may be injected through the diagnostic catheter to verify positioning and / or visualize cardiac anatomy. Fluoroscopic images may be acquired and stored. If guidewire 100 is not positioned as desired, guidewire 100 may be adjusted until it is positioned at the desired location within the cardiac anatomy. The diagnostic catheter may be removed, leaving guidewire 100 in place.In certain embodiments, without injecting more contrast, guidewire 100 and any radiopaque markers on the guidewire (e.g., 151, 152, and / or 153) can be visualized using fluoroscopy, and an evaluation can be performed to determine whether guidewire 100 has strayed out of a desired location based at least in part on the visualization step (e.g., with radiopaque markers 151 and / or 152 located in the left ventricle and radiopaque marker 153 located in the aorta). Guidewire 100 can be repositioned as necessary (e.g., if strayed), and a device such as an MCS device and / or VAD can be delivered over the guidewire. In some embodiments, the method can include positioning (e.g., axially) a radiopaque marker of the MCS device and / or VAD relative to (e.g., adjacent to or aligned with) the radiopaque markers of guidewire 100.

[0121] In some embodiments, a method of delivering a device to a patient's cardiovascular system may be performed using an embodiment of a guidewire 100 including at least radiopaque markers 151 and 153 as described in connection with FIG. 1A. The method may include delivering the guidewire 100 from an access point (e.g., femoral artery) through a diagnostic catheter, such as a 5Fr catheter or catheter 200 described herein, to position the distal end of the guidewire 100 in the left ventricle. In some embodiments, the placement of the distal end of the guidewire 100 may be confirmed by visualizing and confirming that the radiopaque marker 151 is located in the left ventricle and the radiopaque marker 153 is located in the aorta. Contrast may be injected through the diagnostic catheter to verify positioning and / or visualize the cardiac anatomy. Fluoroscopic images may be acquired and stored. If the guidewire 100 is not positioned as desired, the guidewire 100 may be adjusted until it is positioned in the desired location within the cardiac anatomy. The diagnostic catheter may be removed while leaving the guidewire 100 in place. In certain embodiments, without injecting more contrast, guidewire 100 and any radiopaque markers on the guidewire (e.g., markers 151 and / or markers 153) can be visualized using fluoroscopy, and an evaluation can be performed to determine whether guidewire 100 has strayed out of a desired location based at least in part on the visualization step (e.g., with radiopaque marker 151 located in the left ventricle and / or radiopaque marker 153 located in the aorta). Guidewire 100 can be repositioned as necessary (e.g., if strayed), and a device such as an MCS device and / or a VAD can be delivered over the guidewire. In some embodiments, the method can include positioning (e.g., axially) a radiopaque marker of the MCS device and / or VAD relative to (e.g., adjacent to or aligned with) the radiopaque marker of guidewire 100.

[0122] In some embodiments, a method of delivering a device to a patient's cardiovascular system may be performed using a guidewire 100 including at least radiopaque markers 152 and 153 as described in connection with FIG. 1A. The method may include delivering the guidewire 100 from an access point (e.g., femoral artery) through a diagnostic catheter, such as a 5Fr catheter or catheter 200 described herein, to position a distal end of the guidewire 100 in the left ventricle. In some embodiments, the placement of the guidewire 100 may be confirmed by visualizing and confirming that the radiopaque marker 152 is located in the left ventricle and the radiopaque marker 153 is located in the aorta. In some embodiments, the placement of the guidewire may be confirmed by visualizing and confirming that the aortic valve is located between the radiopaque markers 153 and 152. In some embodiments, contrast may be injected through the diagnostic catheter to verify positioning and / or visualize cardiac anatomy. Fluoroscopic images may be acquired and stored. In some embodiments, the method may include adjusting the guidewire so that the aortic valve is located between markers 152 and 153. The diagnostic catheter may be removed while leaving guidewire 100 in place. In certain embodiments, without injecting more contrast, guidewire 100 and any radiopaque markers on the guidewire (e.g., markers 152 and / or 153) may be visualized using fluoroscopy, and an evaluation may be performed to determine whether guidewire 100 has strayed out of a desired position (e.g., with the aortic valve located between markers 152 and 153) based at least in part on the visualization step. Guidewire 100 may be repositioned as necessary (e.g., if strayed), and a device such as an MCS device and / or a VAD may be delivered over the guidewire.In some embodiments, the method may include positioning (e.g., axially) a radiopaque marker of the MCS device and / or VAD relative to (e.g., adjacent to or aligned with) a radiopaque marker of guidewire 100. Positioning markers 152 and 153 such that the aortic valve is between markers 152 and 153 may position the distal end of guidewire 106 in the left ventricle, pump inlet 66 in the left ventricle, and outflow section 68 in the aorta.

[0123] Any method disclosed herein does not have to be performed in the order described. The methods disclosed herein include specific acts to be performed by a practitioner, but can also include, explicitly or implicitly, any third party instructions for those acts.

[0124] In particular, conditional language used herein, such as "can," "could," "might," "may," "eg," and the like, is generally intended to convey that certain features, elements, and / or steps are optional, unless specifically stated otherwise or understood otherwise within the context in which it is used. As such, such conditional language is not generally intended to imply that the features, elements, and / or steps are in any way required, or that one or more implementations necessarily include logic for determining whether those features, elements, and / or steps are included or always performed, with or without other inputs or prompts. The terms "comprising," "including," "having," and the like, are synonymous and are used inclusively in a non-limiting manner and do not exclude additional elements, features, acts, operations, and the like. Also, the term "or," when used, for example, to connect a list of elements, is used in its inclusive sense (and not its exclusive sense) so that the term "or" refers to one, some, or all of the elements in the list.

[0125] Unless specifically stated otherwise, conjugated language such as the phrase "at least one of X, Y, and Z" is otherwise understood in the context in which it is commonly used to convey that an item, term, etc. can be either X, Y, or Z. Thus, such conjugated language is not generally intended to imply that a particular implementation requires the presence of at least one of X, at least one of Y, and at least one of Z.

[0126] As used herein, degree-expressing phrases used herein, such as the terms "approximately," "about," "generally," and "substantially," refer to values, amounts, or characteristics that are close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms "approximately," "about," "generally," and "substantially" can refer to amounts that are less than 10%, less than 5%, less than 1%, less than 0.1%, and less than 0.01% of the stated amount. As another example, in certain implementations, the terms "generally parallel" and "substantially parallel" refer to values, amounts, or characteristics that deviate from exactly parallel by no more than 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, 0.1 degrees, or otherwise.

[0127] Any method disclosed herein does not have to be performed in the order described. The methods disclosed herein include specific acts to be performed by a practitioner, but can also include, explicitly or implicitly, any third party instructions for those acts.

[0128] The methods and tasks described herein may be performed by a computer system and may be fully automated. The computer system may, in some cases, include multiple separate computers or computing devices (e.g., physical servers, workstations, storage arrays, cloud computing resources, etc.) that communicate and interoperate over a network to perform the described functions. Each such computing device typically includes a processor (or multiple processors) that executes program instructions or modules stored in a memory or other non-transitory computer-readable storage medium or device (e.g., solid-state storage devices, disk drives, etc.). Various functions disclosed herein may be embodied in such program instructions and / or implemented in the computer system's application-specific circuitry (e.g., ASIC or FPGA). When a computer system includes multiple computing devices, these devices may, but need not, be in the same location. The results of the methods and tasks of the present disclosure may be persistently stored by converting physical storage devices, such as solid-state memory chips and / or magnetic disks, to different states. The computer system may be a cloud-based computing system whose processing resources are shared by multiple separate entities or other users.

[0129] Although the above detailed description has shown, described and pointed out novel features, it can be understood that various omissions, substitutions and changes in the form and details of the described devices or algorithms can be made without departing from the spirit of the present disclosure. As can be recognized, some features can be used or practiced separately from other features, and therefore certain portions of the description herein can be embodied in forms that do not provide all of the features and benefits described herein. The scope of the specific implementation forms disclosed herein is indicated by the appended claims, rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are intended to be embraced within their scope.

Claims

1. A guide wire configured to traverse a catheter having one or more side holes, said guide wire comprising: a proximal end; a distal end having a length greater than the maximum diameter of said one or more side holes and including a distal advancement segment configured to traverse distally through said catheter without exiting said one or more side holes of said catheter; and an elongate flexible body extending between said proximal end and said distal end, said elongate flexible body having a distal region extending between a distal transition portion and said distal end, said distal region having a spiral coil shape.

2. The guide wire according to claim 1, wherein said distal advancement segment has an elongate straight tip.

3. The guide wire according to claim 1, wherein a minimum length of said distal advancement segment is from about 0.5 mm to about 3.5 mm.

4. The guide wire according to claim 1, wherein a maximum angle between a central axis of said distal advancement segment and a longitudinal axis of said catheter is from about 5° to about 85°.

5. The guide wire according to claim 1, wherein said distal advancement segment includes a curved advancement segment extending from an inflection point of a distal end of said spiral coil shape.

6. The guide wire according to claim 5, wherein said spiral coil shape is concave in a first direction and said distal advancement segment is concave in a second direction.

7. The guide wire according to claim 5, wherein said distal advancement segment includes a first curved region having a first inflection point and a second curved region having a second inflection point.

8. The guide wire according to claim 7, wherein said first curved region and / or said second curved region includes an arc length greater than a maximum diameter of said one or more side holes.

9. The guide wire according to claim 8, wherein said arc length is greater than about 0.5 mm.

10. The guide wire according to claim 7, wherein a maximum angle between a longitudinal axis of said catheter and a central axis of a portion of said distal advancement segment extending distally from said second inflection point is from about 5° to about 85°.

11. The guide wire according to claim 10, wherein said maximum angle between a longitudinal axis of said catheter and a central axis of said portion of said distal advancement segment extending distally from said second inflection point is from about 10° to about 60°.

12. The maximum length of a portion of the distal advancement segment extending distally from the second inflection point is from about 0.3 mm to about 4 mm, the guide wire according to claim 7.

13. The radius of curvature of the first inflection point and / or the second inflection point is greater than the radius of the one or more side holes, the guide wire according to claim 7.

14. The radius of curvature of the first inflection point and / or the second inflection point is from about 0.5 mm to about 0.8 mm, the guide wire according to claim 13.

15. The diameter at the maximum cross section of the distal advancement segment is equal to or greater than the diameter of the one or more side holes, the guide wire according to claim 1.

16. The distal advancement segment is an oblate spheroid, the guide wire according to claim 1.

17. The diameter at the maximum cross section of the distal advancement segment is from about 0.8 mm to about 1 mm, the guide wire according to claim 1.

18. The distal end has a rounded shape, the guide wire according to claim 1.

19. The elongated flexible body comprises a core including a plurality of segments having different diameters, the guide wire according to claim 1.

20. The elongated flexible body further comprises one or more coils of wire surrounding the core, the guide wire according to claim 19.

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