JP2017533760A - Apparatus, system and method for guided tip bushing for rotational atherectomy - Google Patents

Abstract

A high speed rotating atherectomy device for incising an arterial stenosis with a predetermined diameter has a guide wire and a flexible, slender, rotatable proximal end and distal end and can be advanced along the guide wire And a guide member fixedly attached to the drive shaft. When the guide member advances to constriction, the guide member creates a guide hole when the drive shaft is rotated.

Description

Inventor Nicholas Elaling, Crystal, Minnesota, United States citizen.
Joseph Higgins, Minnetonka, Minnesota, United States citizens.

This application is a continuation-in-part of US patent application Ser. No. 14/166207 filed Jan. 28, 2014, and is a provisional application number filed Mar. 14, 2013. The priority of the application of 61/782083 is claimed, and the content of the prior application is incorporated herein by reference in its entirety.

The present invention relates to an apparatus and method for removal of tissue from a body passageway, such as removal of atherosclerotic plaque from an artery, using a high speed rotating atherectomy device.

Description of Related Art Various techniques and instruments have been developed for use in the removal or repair of tissue in arteries and similar body passages. A common purpose of such techniques and instruments is the removal of atherosclerotic plaques in patient arteries. Atherosclerosis is characterized by the accumulation of fatty deposits (atheromas) in the intima layer (under the endothelium) of the patient's blood vessels. What is originally relatively soft and precipitates as a cholesterol-rich atheromatous substance will very often stone over time, resulting in a calcified atherosclerotic plaque. Such atheroma restricts blood flow and is therefore often referred to as a stenotic lesion or stenosis, and substances that inhibit are called stenosis. If left untreated, such stenosis can cause angina, hypertension, myocardial infarction, stroke, and the like.

  Rotational atherectomy has become a common technique for removing such stenosis. Such surgery is most often used to initiate the opening of coronary artery calcified lesions. Rotational atherectomy is most often not used alone, followed by balloon angioplasty, and very often balloon angioplasty is a stent placement that helps maintain open artery patency Followed. In non-calcified lesions, balloon angioplasty is most often used alone to open the arteries and stents are often placed to maintain the patency of the open arteries. However, studies have shown that a significant proportion of patients who experience balloon angioplasty and have a stent placed in an artery experience stent restenosis. Stent restenosis is occlusion by a stent, most often growing with time, resulting in excessive growth of scar tissue in the stent. In these situations, atherectomy is more preferred to remove excess scar tissue from the stent (balloon angioplasty is less effective in the stent) and consequently restore arterial patency. Surgery.

  Several types of rotary atherectomy devices have been developed with the intent of removing the stenosis. One type of device, as disclosed in U.S. Pat. No. 4,990,134 (Auth), is supported at the distal end of a flexible drive shaft by a burr covered with an abrasive abrasive material such as diamond particles. . The bar rotates at high speed (typically, for example, in the range of approximately 150,000 to 190000 rpm) while it is advanced across the stenosis. However, when the bar removes stenotic tissue, the bar impedes blood flow. As the bar is advanced across the stenosis, the artery will be expanded to a diameter equal to or slightly larger than the maximum outer diameter of the bar. Often one or more sized bars must be used to expand the artery to the desired diameter.

  US Pat. No. 5,314,438 (Shturman) discloses another atherectomy device having a drive shaft. A portion of the drive shaft has an enlarged diameter. At least a portion of the enlarged surface is covered with a grinding material that defines a grinding portion of the drive shaft. During high-speed rotation, the grinding part can remove arterial stenosis. Although this atherectomy device has certain advantages in its flexibility over the Auth device, the device is not naturally eccentric so that the arteries only have a diameter approximately equal to the diameter of the enlarged polished surface of the drive shaft. It is also possible to open

  US Pat. No. 6,494,890 (Shturman) discloses a known atherectomy device having a drive shaft with an enlarged eccentric portion, at least a portion of which is covered with abrasive material. When rotating at high speed, the grinding section can remove the stenosis from the artery. This device can open the artery to a diameter larger than the resting diameter of the enlarged eccentric part due in part to orbital rotational movement during high speed operation. Since the enlarged eccentric portion includes drive shaft wires that are not coupled together, the enlarged eccentric portion of the drive shaft can be bent during placement in a stenosis or during high speed operation. This bend allows a wider diameter to open during high speed operation, but can also cause a less desirable degree of control beyond the diameter of the artery that is actually polished. In addition, some stenotic tissues block passages so perfectly that the Shturman device cannot be placed therethrough. Shturman requires an expanding eccentric part of the drive shaft that is placed in the stenotic tissue to achieve polishing, so the effect is weak if the expanding eccentric part impedes movement within the stenosis Become. The disclosure of US Pat. No. 6,494,890 is hereby incorporated by reference in its entirety.

  U.S. Pat. No. 5,681,336 (Clement) provides a known eccentric tissue removal bar with a coating of abrasive particles secured to a portion of its outer surface with a suitable bonding material. However, Clement is a CoI. As described in line 3, lines 53-55, this structure is limited by the fact that the asymmetric bar is rotated at “slower than used in high speed polishing to compensate for heat or imbalance”. . That is, given both the size and mass of the solid bar, it is not feasible to rotate the bar at the high speed used during atherectomy, ie, 20000-200000 rpm. Basically, a center of gravity deviating from the rotational axis of the drive shaft will result in the development of significant centrifugal forces, exerting excessive pressure on the arterial wall, generating excessive heat and excessive particles.

  There are also situations where the high rotational speed of the atherectomy device can be screwed into the lesion when the device is driven in the lesion. Furthermore, the atherectomy device may be limited to the treatment of certain size lesions or stenosis due to the diameter of the bar. For these or other reasons, it may be highly desirable to include a grinding structure placed distally from the polishing bar to first create a guide hole in the stenosis before the polishing head contacts the stenosis. . Prior art devices, such as, for example, US Pat. No. 6,482,216 (Hiblar), are mounted on a drive shaft to remove precipitate from a vessel or stent without starting to embed in the precipitate as a grinding tip that works on the precipitate. A concentric grinding bar and a concentric grinding tip mounted at the end of a guide wire are proposed. However, with such devices, the treatment diameter and passage are limited to the smallest sized lesion.

  The present invention overcomes these deficiencies and provides in particular the improvements described above.

SUMMARY OF THE INVENTION This system is directed to various methods, devices and systems related to rotational atherectomy. More specifically, the guide tip is mounted on the drive shaft, and the guide tip or bushing has a shape and structure that helps open the guide hole for difficult occlusions and / or stenosis.

  In some embodiments, a high speed rotating atherectomy device for opening a stenosis in an artery having a given diameter is flexible and elongated with a guidewire having a maximum diameter smaller than the diameter of the artery A drive shaft advanceable along the guide wire and having a proximal end and a distal end, and a guide member rigidly attached to the drive shaft proximate the distal end. In some embodiments, the guide member has a concentric or eccentric shape.

  In at least one embodiment, the guide member or guide tip extends distally from the proximal end of the guide member and extends proximally with a proximal portion having a constant diameter and distal from the proximal end of the guide member. A distal portion having a diameter that increases with increasing distance from a distal end having a diameter smaller than the diameter of the proximal end of the member, and a generally parabolic shape between the proximal portion and the distal portion. Having an intermediate portion. The diameter of the guide member increases from a constant diameter of the proximal portion to a maximum point and then decreases as it becomes distal toward the distal portion. The guide tip may be concentric or eccentric. In some embodiments, the guide tip has an internal lumen at least in a proximal portion with a diameter greater than the diameter of the drive shaft. In at least one embodiment, the guide tip has a diameter that is smaller than the diameter of the drive shaft.

  A method of opening a stenosis in a blood vessel having a given diameter is also presented, the method comprising providing a guide wire having a maximum diameter smaller than the diameter of the artery and guiding the wire into the blood vessel to a location near the stenosis. And providing a drive shaft that is flexible, elongate and rotatable along the guide wire. The drive shaft has a maximum diameter that is smaller than the diameter of the artery. The drive shaft has a rotation shaft. The drive shaft has a guide tip that is rigidly attached to the drive shaft. The method comprises the steps of advancing the guide tip through the artery to a position near the stenosis and generating a guide hole by rotating the drive shaft at a sufficient rotational speed. In some embodiments, the guide tip has an orbital path that results in a guide hole having a diameter that is larger than the maximum diameter of the guide tip.

1 is a perspective view of a rotary atherectomy device of the present invention. It is a perspective view of the example of the guidance tip of the present invention. FIG. 3 is a side view of the example of the guide tip of FIG. 2. FIG. 4 is a view from the distal end of the tip of the example of the guide tip of FIGS. FIG. 5 is a view from the proximal end of the tip of the example of the guide tip of FIGS. It is a perspective view of the example of the guidance tip of the present invention. FIG. 7 is a side view of the example of the guide tip of FIG. 6. FIG. 8 is a view from the distal end of the tip of the example of the guide tip of FIGS. FIG. 9 is a view from the proximal end of the tip of the example of the guide tip of FIGS. It is a perspective view of other embodiment of a rotary atherectomy apparatus.

DETAILED DESCRIPTION While the invention is amenable to various modifications and alternative forms, details thereof have been shown by way of example in the drawings and herein. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. Rather, all modifications, equivalent and alternative embodiments are intended to be within the spirit and scope of the present invention.

  Various embodiments of the present invention are described in US Pat. No. 6,494,890, entitled “Eccentric Rotating Atherotomy Device”, which is incorporated herein by reference. Is provided. In addition, the disclosure of the following shared patents or patent applications is hereby incorporated by reference in its entirety: US Pat. No. 6,295,712 entitled “Rotary atherectomy device”, “For atherectomy device” US Pat. No. 6,132,444 entitled “Eccentric Drive Shaft and Method of Manufacturing the Same”, US Pat. No. 6,638,288 entitled “Eccentric Drive Shaft for Atherotomy Device and Method of Producing the Same”, “Rotary Atherome” US Pat. No. 5,314,438 entitled “Grinding Drive Shaft Device for Ablation”, US Pat. No. 6,217,595 entitled “Rotary Atherotomy Device”, US Pat. No. 5,554,163 entitled “Atherotomy Device” US Pat. No. 7,507,245 entitled “Rotary angioplasty device with grinding crown”, “radially expandable” US Pat. No. 6,129,734 entitled “Rotary atherectomy device with flexible prime mover connection”, US Pat. No. 8,597,313 entitled “Eccentric polished head for high speed rotary atherectomy device”, “Occlusion lesion” US Pat. No. 8439937 entitled “System, Apparatus and Method for Opening a Site”, US Patent Application No. 2009/0299392 entitled “Eccentric Abrasive Element for High Speed Rotating Atherotomy Device”, “ US Patent Application No. 2010/0198239 entitled “Multi-materialized polishing head for atherectomy device with laterally displaced center of gravity”, entitled “Rotary atherectomy device with pre-bent drive shaft” US Patent Application No. 2010/0036402, “Eccentric study for high-speed rotary atherectomy device” And US Patent Application No. 2009/0299391 entitled “Eccentric Grinding and Cutting Head for High Speed Rotating Atherotomy Device”, US Patent Application No. 2010/0100110, “ US Design Patent No. D610258 entitled “Rotary Atherotomy Grinding Crown”, US Design Patent No. D6107102 entitled “Rotary Atherotomy Grinding Crown”, “Bidirectional for Rotary Atherotomy Machine” U.S. Patent Application No. 2009/0306869 entitled "Expandable Head", U.S. Patent Application No. 2010/0211088 entitled "Rotary Atherotomy Segmented Polishing Head and Method for Improving Polishing Efficiency", and " US patent application 2013/0018 entitled "Rotary atherectomy device with electric motor" 398. The present invention contemplates that features of one or more embodiments of the present invention may be combined with one or more features of the above-described atherectomy device embodiments.

  FIG. 1 illustrates one embodiment of a rotary atherectomy device according to the present invention. The apparatus comprises a handle portion 10, an elongate and flexible drive shaft 20, and an elongated catheter 13 extending distally from the handle portion 10. The drive shaft 20 comprises an eccentric grinding head 28 and a guide portion comprised of either a guide tip or a bushing 29 that would otherwise be located at a point distal to the flexible drive shaft grinding head 28. And have. The drive shaft 20 is constructed of a helical coiled wire as is known to those skilled in the art, and the grinding head 28 and the guide tip or bushing 29 are rigidly attached to the drive shaft 20. The drive shaft 20 has an inner surface 22 and an outer surface 24 that define an inner lumen, allowing the drive shaft 20 to advance and rotate along the guide wire 15. Catheter 13 has a lumen in which most of the length of drive shaft 20 is disposed therein, except for the enlarged grinding head 28 and the portion of drive shaft 20 distal to enlarged grinding head 28. A liquid supply line 17 may be provided to introduce a cooling or lubricating liquid (typically saline or other biocompatible liquid) into the catheter 13.

  FIG. 10 is another embodiment of a rotary atherectomy device that does not include a grinding head (or grinding portion) 28. In all other respects, the embodiment illustrated in FIG. 10 is substantially similar to the embodiment described with reference to FIG.

  The handle 10 is strongly desired to include a turbine (or similar rotary drive mechanism) to rotate the drive shaft 20 at high speed. The handle 10 is typically coupled to a power source such as compressed air provided from the tube 16. A pair of fiber optic cables 25 may alternatively be used, but one fiber optic cable may be used, but may be provided to monitor the rotational speed of the turbine and drive shaft 20 (details and related details regarding such handles). Such devices are known to those skilled in the art and are described in US Pat. No. 5,314,407, acquired by Auth). The handle 10 also preferably includes a control knob 11 for advancing and retracting the turbine and drive shaft 20 relative to the catheter 13 and the body of the handle.

  As described above, in at least one embodiment, the eccentric grinding head 28 comprises an eccentric enlarged portion of the drive shaft, or an eccentric solid crown, or an eccentric bar attached to the drive shaft. In some embodiments, the grinding portion 28 has a center of gravity radially spaced from the rotational axis of the drive shaft 20 and is configured to open a stenotic lesion to a diameter substantially larger than the outer diameter of the grinding portion 28. Promote ability. This is spaced from the geometric center of the grinding part 28, i.e. an eccentric, enlarged diameter part of the drive shaft 20, away from the rotational axis of the drive shaft 20, or an eccentric solid grinding head or crown, Alternatively, it can be achieved by a bar attached to the drive shaft 20. Alternatively, by providing the grinding head 28 made of different combinations of materials, the center of gravity of the grinding head 28 may be separated from the rotation axis of the drive shaft in the radial direction. This can produce an eccentricity as defined herein by constructing one side of at least one grinding head 28 with a material that is larger or denser than the opposite side. As will be appreciated by those skilled in the art, the creation of eccentricity by using different materials in the structure of the grinding head 28, such as the center of gravity offset from the rotational axis of the drive shaft, is discussed herein. Applicable to all embodiments of the grinding head 28, concentric or eccentric solid bars, partially hollow crowns, or grinding heads, or enlarged parts of the drive shaft, or equivalent. When rotating at a high rotational speed, the drive shaft 20 encourages an orbital motion of the eccentric grinding head 28 to produce a cutting diameter that is larger than the diameter of the grinding head.

  In the present invention, the grinding head 28 may have a concentric shape or an eccentric shape. In some embodiments, the grinding head 28 uses different density materials and / or moves the center of gravity of the grinding head 28 geometrically away from the center of gravity of the drive shaft in a radial direction. Thus, the orbital motion generated by the position of the center of gravity of the grinding head 28 shifted in the radial direction from the rotational axis of the drive shaft may be achieved. This “eccentricity” can be achieved with either a concentric or eccentric profile. The grinding head 28 may be an enlarged part of the drive shaft, a bar or a shaped grinding element and may comprise a diamond coating. In other embodiments, the grinding head 28 may have a center of gravity on the rotational axis of the drive shaft.

  However, these known grinding heads 28 are limited to the smallest size lesions that can be treated. The reason is that the grinding feature of the grinding element is a diameter larger than the diameter of the drive shaft. This device particularly improves the problem. In addition, if a known grinding element is subjected to force and driven into the lesion, the grinding head 28 is gripped into the lesion, screwed / drilled, and subsequently has an undesirable effect on the lesion or blood vessel. The force that can be applied can be generated and released. The present invention addresses this problem by drilling a guide hole with a diameter equal to the diameter of the flexible drive shaft of the atherectomy system. This allows the minimum necessary clearance between the grinding head and the lesion and prevents gripping and screwing in the lesion.

  The guide tip or bushing 29 is rigidly attached to the drive shaft 20 by being mounted directly on the outer surface of the drive shaft or by being axially mounted on the drive shaft at the distal end of the drive shaft. Also good. Since the guide tip or bushing 29 is firmly attached to the drive shaft 20 to which the grinding head is also attached, the guide tip or bushing rotates in the same direction as the grinding head 28 at the same speed.

  The guide tip or bushing 29 may be coupled to the drive shaft 20 with a concentric or eccentric outer diameter grinding head 28 as described with reference to FIG. In other embodiments, the guide tip or bushing 29 may be coupled to the drive shaft 20 without the grinding head 28. The guide tip or bushing 29 may be coupled to the grinding head 28 in either a geometrically decentered shape or a concentric shape by a center of gravity of the grinding head that is radially offset from the center of gravity of the drive shaft. Good. The guide tip or bushing 29 may be coupled with a geometrically eccentric profile such that the center of gravity of the grinding head is collinear with the center of gravity of the drive shaft, or a grinding head 28 with a concentric profile. The guide tip or bushing 29 coupled with the drive shaft 20 with or without the grinding head 28 may also have a concentric or eccentric profile. Regardless of the presence or absence of the grinding head, the guide tip or bushing 29 may be collinear with the rotational axis of the drive shaft or the rotational axis of the drive shaft using techniques similar to those described above in connection with the grinding element. May be provided with a center of gravity deviating from the radial direction. Thus, in the absence of the grinding head 28, the guiding tip or bushing 29 so configured will have operating characteristics similar to those described for the grinding head 28. In at least one embodiment where the grinding head is eccentric and the guiding tip or bushing is concentric, the grinding head causes orbital motion of the guiding tip, resulting in a rotational diameter of the grinding head. It will work as a counterweight to increase. In some embodiments, the grinding head and the guide tip are both eccentric, and in still other embodiments, the grinding head and the guide tip are both concentric. In a non-limiting exemplary embodiment without a grinding head 28, the eccentricity and / or center of gravity position of the guide tip or bushing 29 can also increase the rotational working diameter.

  A guide tip or bushing 29 can be located along the drive shaft 20 away from the grinding head 28. In other embodiments, the proximal end of the bushing or guide tip is adjacent to the distal end of the grinding head 28. The guide tip or bushing 29 in at least some embodiments comprises a distal most tip of the same diameter as the drive shaft that facilitates opening the stenosis in preparation for rotational entry of the grinding element into the stenosis.

  The guide tip or bushing 29 may have the outline illustrated in FIGS. The guide tip or bushing 29 has a proximal end 42, a distal end 44, an outer surface 46, and an inner surface 48 that defines a lumen. In some embodiments where the guide tip or bushing 29 is rigidly positioned relative to the outer surface of the drive shaft 20, the bushing 29 or guide tip inner surface 48 is paired with the outer surface 24 of the drive shaft 20. Or engaged. In other embodiments, the guide tip or bushing 29 may be rigidly attached to the distal end of the drive shaft 20, and the lumen defined by the inner surface 48 causes the guide tip or bushing 29 to follow the guide wire 15. Can be moved forward and rotated. Importantly, the guide tip or bushing 29 is external to the drive shaft or distal to the drive shaft 20 so as to rotate simultaneously, rather than separately or selectively from the grinding head. Mounted firmly on the edge.

  The guide tip or bushing 29 may have a shape with a distal end having a smaller diameter than the proximal end. In some embodiments, the diameter of the guide tip increases from the distal end 44 to the proximal end 42. In some embodiments, the guide tip has a spherical shape. In some embodiments, such as the embodiment shown in FIGS. 2-3, the outer diameter of the guide tip or bushing 29 has a constant diameter at the proximal portion extending distally from the proximal end 42. However, in the intermediate portion, the diameter of the guide tip or bushing 29 increases to the maximum point of the distal end of the intermediate portion, and in the distal portion, the diameter of the guide tip or bushing gradually decreases with a constant inclination with respect to the diameter. The distal end 44 is narrower than the constant diameter of the proximal end. In some embodiments, such as those shown in FIGS. 6-7, the outer diameter of the guide tip or bushing 29 is a constant diameter in the proximal portion extending distally of the proximal end 42. Have. In the intermediate portion, the diameter of the guide tip or bushing 29 increases to the maximum point of the distal end of the intermediate portion, and the outer diameter of the guide tip and bushing is the diameter at the distal end 44 that is smaller than the constant diameter of the proximal end. It decreases to. In some embodiments, the outer diameter of the guide tip may be reduced to a smaller diameter than the outer diameter of the drive shaft. In the embodiment shown in FIGS. 2 to 9, the guide tip is symmetric with respect to the central axis. In yet another embodiment, the guide tip is asymmetric with respect to the central axis and has a trajectory path that may or may not be the same as the trajectory path of the grinding head.

  The guide tip or bushing 29 may have a grinding coating disposed on some or all of the outer surface 46 of the guide tip or bushing 29. The abrasive coating may be placed in discrete areas to form the desired pattern. In some embodiments, the guide tip or bushing 29 has a cutting feature on the outer surface 46. In some embodiments, the guide tip or bushing 29 has an impact feature on the outer surface 46. In some embodiments, the guide tip or bushing 29 has a thread-like cutting mechanism disposed on the outer surface 46. In some embodiments, the guide tip or bushing 29 is formed like an auger drill bit with a helical thread blade.

  In some embodiments, the guide tip or bushing 29 creates a guide lumen through the stenosis or creates a cavity extending distally from the guide hole into the stenosis, as will be apparent to those skilled in the art. May be used for For example, in a non-limiting exemplary embodiment, this can be accomplished by continuing to advance the guide tip or bushing 29 distally through the stenosis after the guide hole has been drilled. Therefore, the guide lumen is generated by an atherectomy device with a grinding head 28 or an atherectomy device without a grinding head 28. In devices having a grinding head 28 proximal to the guide tip or bushing 29, the guide lumen is generated by placing the grinding head 28 and the guide tip or bushing 29 at a distance approximately equal to the length of the stenosis. sell. As noted elsewhere, in a non-limiting exemplary embodiment, by attaching an element with mass proximal and / or distal to the guiding tip or bushing to cause an eccentric rotational trajectory By using an eccentric guide tube or bushing, the diameter of the guide lumen is made larger than the maximum outer diameter of the guide tip or bushing 29 by using a guide tip or bushing having a center of gravity offset radially from the axis of rotation. sell. As a non-limiting exemplary embodiment, the grinding head 28 may be used to generate a guide lumen diameter that is greater than the maximum outer diameter of the guide tip or bushing 29, as described elsewhere. Good. As described herein, other embodiments of configuring and / or using a guide tip or bushing 29 that creates a guide hole and / or guide lumen through the stenosis will be apparent to those skilled in the art. All such embodiments are considered to be within the boundaries of the claimed disclosure.

  A method for opening a stenosis in a blood vessel having a given diameter, comprising providing a guide wire having a maximum diameter smaller than the diameter of an artery, and advancing the guide wire into the blood vessel to a location near the stenosis And providing a drive shaft that is flexible, elongate and rotatable along the guide wire. The drive shaft has a maximum diameter that is smaller than the diameter of the artery. The drive shaft has a rotation shaft. The drive shaft has at least one eccentric grinding head and a guide tip rigidly attached to the drive shaft. The method includes advancing the guide tip through the artery to a position near the stenosis, generating a guide hole by rotating the drive shaft at a sufficient rotational speed, and passing an eccentric grinding head through the guide hole. Advancing, rotating the drive shaft at the rotational speed and moving it across the lesion, thereby opening the stenotic lesion to a diameter larger than the nominal diameter of the eccentric expanded diameter portion.

  Any and all of the above combinations of guiding tips or bushings and grinding elements in a rotary atherectomy system are within the scope of the present invention. The present invention should not be considered limited to the particular examples described above, but rather should be understood to cover all aspects of the invention. Various modifications, equivalent processes, and numerous structures to which the present invention may be applicable will be readily apparent to those of ordinary skill in the art upon review of this specification.

Claims (30)

A rotary atherectomy device for opening a stenosis in an artery having a predetermined diameter,
A guide wire having a maximum diameter smaller than the diameter of the artery;
A drive shaft that is flexible, elongated, rotatable, advanceable along the guidewire, and having a proximal end and a distal end;
A guide member rigidly attached to the drive shaft,
The guide member is
A proximal portion extending distally from the proximal end of the guide member and having a substantially constant diameter;
A distal portion extending distally from a proximal end of the guide member;
A rotary atherectomy device comprising an intermediate portion extending between the proximal portion and the distal portion.   The rotary atherectomy device according to claim 1, wherein the guide members are concentric or eccentric.   The rotary atherectomy device according to claim 1, wherein the guide member is mounted on an outer surface of the drive shaft or in an axial direction of the drive shaft.   The rotary atherectomy device of claim 1, wherein the guide member is mounted proximate to or at a distal end of the drive shaft.   The rotary atherectomy device according to claim 1, wherein the guide member has a spherical shape.   The rotary atherectomy device according to claim 1, wherein a diameter of the distal portion increases with increasing proximity from the distal end of the guide member.   The rotary atherectomy device according to claim 1, wherein a diameter of the distal end of the guide member is smaller than a diameter of a proximal end of the guide member or a diameter of the drive shaft. The intermediate portion has a generally parabolic shape;
The rotational atherectomy device according to claim 1, wherein the diameter of the intermediate portion increases distally from the proximal portion to the maximum diameter and then decreases distally to the distal portion.   The rotary atherectomy device according to claim 1, wherein the diameter of the intermediate portion increases with increasing proximity from the proximal portion to the maximum diameter of the distal end of the intermediate portion.   2. The rotary atherectomy device according to claim 1, wherein the guide member has a center of gravity that is collinear with a rotation axis of the drive shaft or is shifted in a radial direction from the rotation axis.   The rotary atherectomy device according to claim 1, wherein the guide member is symmetric or asymmetric with respect to a central axis.   The rotary atherectomy device according to claim 1, wherein at least a portion of the outer surface of the guide member comprises one of a grinding coating, a cutting mechanism, a collision mechanism, and an auger. The leading tip of a rotary atherectomy device,
A proximal portion extending distally from the proximal end of the guide tip and having a substantially constant diameter;
A distal portion extending distally from a proximal end of the guide tip;
A guide tip including an intermediate portion extending between the proximal portion and the distal portion.   14. A guide tip according to claim 13, wherein the diameter of the distal portion increases with increasing proximity from the distal end of the guide tip.   The guide tip of claim 13, wherein the diameter of the distal end of the guide tip is smaller than the diameter of the proximal end of the guide tip. The intermediate portion has a generally parabolic shape;
14. The guide tip of claim 13, wherein the diameter of the intermediate portion increases with increasing distance from the proximal portion to the maximum diameter and then decreases with increasing distance to the distal portion.   14. The guide tip of claim 13, wherein the diameter of the intermediate portion increases with increasing proximity from the proximal portion to the maximum diameter of the distal end of the intermediate portion.   The guide tip of claim 13, wherein the guide tip is symmetric or asymmetric with respect to a central axis.   The guide tip of claim 13, wherein at least a portion of the outer surface of the guide tip comprises one of a grinding coating, a cutting mechanism, a collision mechanism, and an auger.   14. The guide tip of claim 13, wherein the guide tip is rigidly attached to an elongated, flexible, rotatable drive shaft of the device.   21. A guide tip according to claim 20, wherein the guide tip is concentric or eccentric with respect to the rotational axis of the drive shaft.   The guide tip according to claim 20, wherein the guide tip is mounted on an outer surface of the drive shaft or in an axial direction of the drive shaft.   21. The guide tip of claim 20, wherein the guide tip is mounted proximate to or at a distal end of the drive shaft.   21. The guide tip of claim 20, wherein a diameter of the distal end of the guide tip is smaller than a diameter of the drive shaft.   21. The guide tip according to claim 20, comprising a center of gravity that is collinear with a rotational axis of the drive shaft or deviated in a radial direction from the rotational shaft. An internal lumen in at least a portion of the proximal portion;
21. A guide tip according to claim 20, wherein the inner lumen comprises a diameter greater than the diameter of the drive shaft. A method for providing a guide hole for stenosis in a blood vessel, comprising:
Providing a guide wire having a maximum diameter smaller than the diameter of the blood vessel;
Advancing a guide wire into the blood vessel to a position near the stenosis;
Providing a drive shaft that is flexible, elongated, rotatable and advanceable along the guidewire;
The drive shaft is
A maximum diameter smaller than the diameter of the blood vessel;
A guide tip rigidly attached to the drive shaft adjacent to its distal end,
The guiding tip is
A proximal portion extending distally from the proximal end of the guide member and having a substantially constant diameter;
A distal portion extending distally from a proximal end of the guide member;
An intermediate portion extending between the proximal portion and the distal portion;
The method
Advancing the drive shaft in the blood vessel along the guide wire;
Placing the guide tip near the stenosis;
Rotating the drive shaft;
Advancing the guide tip distally within the stenosis while the precursor drive shaft is rotating;
Generating a guide hole in the stenosis.   28. The method of claim 27, comprising providing a guide tip configured to generate the guide hole having a diameter greater than a maximum diameter of the guide tip. Advancing the guide tip distally within the stenosis while the drive shaft is rotating;
28. A method according to claim 27, comprising generating a cavity or a guiding lumen through the stenosis in the stenosis.   30. The method of claim 29, comprising providing a guide tip configured to create a cavity or internal lumen having a diameter greater than a maximum diameter of the guide tip.

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