DE4413291A1 - Method and device for controlling the movement of a medical shaft - Google Patents

Abstract

Device for use with a catheter which has a longitudinally extending lumen, provided with a shaft insertable in the lumen and with a housing designed such that it restrains a proximal end of the catheter against lateral movement. The housing has a catheter reception groove, and there is a device for generating a differential holding force within the housing in order to prevent a longitudinal movement of the shaft whereas a longitudinal movement of the catheter is possible. The shaft can be a guide wire with a magnetically active segment, and there may be an electrical coil arrangement which is arranged around the magnetically active segment on the guide wire such that a magnetic force formed between these couples the coil arrangement and the guide wire in order to provide signals which are characteristic of the relative position and movement between the guide wire and the catheter part. <IMAGE>

Description

The present invention is concerned with medical devices, especially Kathe tern. In particular, the present invention relates to a method and a device device for controlling the movement of an elongated shaft for use in Catheterize a patient with a portion of the shaft inserted into the patient becomes.

Angioplasty has been widely accepted as efficient and ef in recent years fective method for treating various types of vascular diseases acquired. In particular, angioplasty is widely used to treat stenoses Open coronary arteries. Angioplasty is also used to treat Ste noses used in other parts of the vascular system.

The most common form of angioplasty is a dilatation catheter used, which carries an expandable balloon at its distal end. Among users After performing a fluoroscopic procedure, the doctor guides the dilatation catheter through the Vascular system until the balloon crosses the stenosis. Then the balloon expanded by a fluid under pressure through an expanding lumen the balloon is forwarded. The balloon's expansion causes the artery to expand and contract Pressing the lesion into the artery wall to get an acceptable blood flow through the Restore artery. For some angioplasty procedures, it may be desirable a group of dilatation catheters of different sizes or balloon confi use gurations.  

In one type of dilatation catheter, a guide lumen is provided in the catheter hen so that a guidewire can be used to guide the way through the stenosis train through. The dilatation catheter is then passed over the guidewire moved until the balloon has reached a point where it passes through the stenosis crosses. The use of a guidewire allows the catheter to be proportionate to move rapidly through the blood vessel, thereby requiring the procedure the time span is shortened.

A "standard" guidewire for use in coronary angioplasty is approximately 175 cm long while a typical coronary angioplasty catheter is approximately 150 cm in length Has. When the catheter is over the guidewire for use, protrudes Part of the guidewire proximal to the catheter. The above part allows manipulation of the guidewire by the doctor. In some cases it can want a dilatation catheter (already on the guidewire) exchange for a second dilatation catheter. Usually it will be before pulls to remove the catheter so that the guidewire is in place in the blood vessel Site can remain so that the next catheter enters the blood vessel over the already Guide wire in place and inserted into the stenosis in the blood can be conducted. To hold a guide wire in place, weh When the catheter is pulled out, the guide wire must be on its proximal End be taken to prevent it together with the catheter from the Blood vessel is pulled out. However, the catheter is longer than the proximal part of the Guide wire that protrudes from the patient. Therefore, the catheter, be before it is fully pulled out, the proximal part of the guidewire fully constantly. As a result, a standard guidewire could not be held to prevent it from being pulled out along with the catheter. To the Pull out the catheter while leaving the guidewire in place a longer effective length guidewire was required.

One measure to avoid this difficulty is to use a Replacement wire when changing the catheter. An exchange wire can be from Used from the beginning or exchanged for a standard guidewire, which is already inserted in the patient. An exchange wire is usually we considerably longer (e.g. 300 cm long) than the typical or standard guidewire. The additional length of the exchange wire leads to a proximal protruding part that is longer than the catheter to be pulled out. When a catheter is removed, one is always clear certain portion of the proximal part of the replacement wire  sets, which ensures that the replacement wire is gripped and in its position in can be held in the blood vessel. The next catheter is then in the patient inserted over the replacement wire.

It is generally considered undesirable to use a number of guidewires during to introduce, push forward and pull out this type of intervention. Repeated Inserting guidewires increases the risk of injury to the patient, and it also extends the time required for the procedure. It also becomes necessary exposing the patient to additional radiation because additional fluoroscopy is necessary the stenosis becomes maneuverable to the subsequent guide wires in a suitable manner to let pass through. Furthermore, long replacement wires are cumbersome and difficult to handle while the guidewire is held in the stenosis.

Techniques have been proposed to address the need for guidewire replacement to avoid. One solution is to use a guidewire extension that is attached to the proximal end of the guidewire while guiding wire remains in place in the patient. The guide wire extension ensures an increase in the length of the guide wire to the length of an off exchange guide wire. During this measure the duration of the procedure is essential shortened because the extension is essential at the proximal end of the guidewire can be attached more quickly than replacing guide wires can be carried out, the extended guide wire is still cumbersome because of Doctors use an extended piece of guidewire outside of the patient during at least handle part of the procedure.

One measure for changing the catheter without lengthening the guide wire is the use of a balloon catheter with a guidewire lumen only adjacent the distal end of the catheter. In this configuration, the guidewire runs outside the balloon catheter except adjacent the distal end of the ball lon catheter. This catheter design allows the catheter to be pulled out the guidewire without the doctor having to let go of the guidewire completely until that distal end of the catheter is outside the patient's body. The Füh The wire lumen of the catheter is shorter than the length of the exposed guide wire tes, so that at least a certain part of the proximal end of the guide wire can be exposed continuously, thereby grasping the guide wire and referring to its position to maintain the stenosis while pulling out the catheter can.  

Another measure for replacing a catheter without using a extended guidewire is to grip the guidewire at one point fen which is distal with respect to the catheter and the guide wire with respect to to keep the stenosis in place. This was done using an expanded baren guidewire holding balloons, which only opened within a guiding catheter can be expanded. With this arrangement, the dila located in the patient tion catheter over the guide wire and within the guide catheter by one withdrawn a short distance. The guidewire retention balloon is distally referenced to the dilatation catheter aligned and then dilated, causing the guidewire is held with respect to an inner wall of the guide catheter (and the guide wire is prevented from moving longitudinally with respect to the guide catheter). Of the The dilatation catheter is then withdrawn over the guidewire (the proximal end of the guidewire can be released), and a second dilata tion catheter is pushed onto the guide wire and along the guide wire is advanced to the location where the guidewire is against the guiding catheter wall is held. The guidewire holding balloon is then deflated and the doctor moves forward the second dilatation catheter along the guidewire to the stenosis To continue the intervention. It has also been disclosed that mechanical means, e.g. a wire loop, used within a guiding catheter instead of a balloon to secure the guidewire in relation to the guiding catheter gene.

While arrangements have been proposed to perform a catheter change at early stage wire / catheter systems to facilitate without having a large guide wire length must be worked, they require a modified catheter (no Full-length guidewire lumen) or additional components within the pati ducks (e.g. balloon to hold the guidewire within the guiding catheter).

It is desirable to provide an arrangement that allows catheter changes to be performed via a guide Standard length guidewire allowed when using a catheter with a guid wire lumens of full length. It is also desirable to provide funds that allow measurement of the distance the guidewire has been moved by in this way to determine the location of the wire.

The present invention is a method and an apparatus for controlling the movement of a shaft for use in catheterizing a Patient with a distal portion of the shaft inserted into the patient. The he invention is also suitable for adjusting a tube or tube with respect to one  shaft extending therethrough, with distal parts of both the tube or Tube and shaft are inserted into a patient.

The device according to the present invention has two together acting parts. The first part is a functional segment the shaft. The second part is an additional tool that, when it is adjacent to the Functional segment is arranged on the shaft, with the functional segment below Formation of a coupling force field between the functional segment and the tool together acts, whereby the tool and the shaft are coupled together. The Force generated between the two parts is sufficiently high to maintain the position of the Shaft with respect to the tool when the pipe is above the Functional segment of the shaft is aligned.

According to a preferred embodiment, the present invention uses to enable a catheter change in a guidewire / catheter system Lichen without the need for a long guide wire. In this preferred In the th embodiment, the shaft is a guide wire, while the tube is a lumen catheter in which the guidewire slides is recorded in cash. The clutch force field between the functional segment the guidewire and the tool is generated by magnetism and is sufficient strong enough to keep the tool and guide wire coupled together, when the catheter is aligned over the guidewire and the catheter is in Longitudinal direction with respect to the guide wire is shifted. The one for training The magnetic coupling force used materials can be permanent magnets or be magnetically permeable material.

The present invention is particularly suitable for changing catheters without that a large length of guidewire or a modified catheter are required. If a guide wire / catheter system designed according to the invention is initially in a patient's vessel is inserted, the original catheter can be used against one second catheter can be replaced by simply the functional segment on the Guide wire is aligned with the tool to create the clutch force field witness; by passing the original catheter proximally past and over the tool the guide wire (which is held stationary with respect to the tool) is pulled until the catheter comes free from the guidewire; by the second Ka is aligned over the guidewire and by the second catheter over the tool and over the guide wire until the second Ka theter reaches its predetermined position. A handle that is firmly attached to the tool  is coupled and can slide with respect to the catheter assembly, ensures a particularly easy actuation. The catheter assembly is inside the tool stabilized by using a geometrically configured catheter receiving groove.

The invention also relates to an apparatus and a method for measuring the movement of the tube and the shaft to their position within the patient to determine. According to a preferred embodiment, two are electri coils around magnetic nodes on the guidewire magnet segment arranged and coupled in this way to sor in the coils for signals gene, which can be used to the movement distance of the guide wire and the To determine the direction of movement.

Preferred embodiments of the invention are below with reference explained in more detail on the drawings. Show it:

Fig. 1 is a schematic view of an angioplasty catheter assembly in the Ge fäßsystem a patient,

Fig. 2 in a larger scale a side view of an embodiment of the Kathe teranordnung, with the holding of the guide wire can be seen.

Fig. 3 is a sectional view of the holding tool of Fig. 2,

Fig. 4 is a detailed sectional view of a functional segment of a guidewire accordingly a preferred embodiment of the present invention,

Fig. 5 is an end view of a preferred embodiment of the arrangement according to the invention,

Fig. 6 is a side view corresponding to the line 6-6 in Fig. 5,

Fig. 7 on a larger scale a detailed view of area A in Fig. 5, which illustrates the arrangement of a catheter assembly shown in section in the tool housing,

Fig. 8-13, a preferred mode of use of the device according to the invention,

Fig. 8 shows the catheter and the guide wire after initial introduction into a Ge fäß of the patient, wherein the functional segment is located on the guidewire in the proximal end of the dilatation catheter,

Fig. 9 placing the tool over the functional segment of the Führungsdrah tes,

Fig. 10, the pulling out of the dilatation catheter over the guide wire and past the tool,

Fig. 11 shows the dilatation catheter located outside the patient's body, where adjacent in the tool is arranged to the functional segment of the guidewire.

Fig. 12 shows the dilatation catheter outside the patient's body, wherein the tools is taken out of the vicinity of the guide wire,

Figure 13 wire. The remaining in place in the vessel of the patient guide, the tool and the dilatation catheter are removed,

Fig. 14 is a detailed sectional view of a functional segment of a guidewire accordingly a modified preferred embodiment of the present the invention,

Fig. 15 is a detailed sectional view of a functional segment of a guidewire accelerator as a further preferred embodiment of the invention,

Fig. 16 is a schematic representation of an extension guidewire with a functional segment,

Fig. 17 is a schematic representation of a tool comprising an electromagnet,

Fig. 18 is an exploded view of the three main components of the tool accelerator as a modified embodiment,

Fig. 19 is a schematic representation of the operation of the modified exporting approximate shape shown in FIG. 18,

Fig. 20 in a larger scale a view of the Katheteraufnahmenut abgewandel th embodiment,

Fig. 21 is a longitudinal sectional view of the proximal end of the guidewire accelerator as a preferred embodiment,

Fig. 22 is a schematic representation of the guide wire movement measuring arrangement according to the invention,

Fig reveals a graph which approximately form the shape of reproduction at the exporting according to Fig. 22. 23,

Fig. 24 is a schematic representation of a further feature of the Bewegungsmeß device according to the present invention,

Fig. 25 is a schematic representation of a guide wire on which a functional segment in the form of a sleeve is mounted, and

Fig. 26 is a schematic cross-sectional view of part of the functional element sleeve according to Fig. 25.

It should be noted that the illustrations in the drawings are not to scale, because certain parts are shown enlarged for clarity.

Fig. 1 a vascular system 20 and a schematically shows angioplasty catheter assembly 32. In the case of an angioplasty procedure, access to the vascular system 20 typically takes place via a femoral artery, as is schematically indicated at 21 in FIGS . 2 and 8. A distal part of the vascular system 20 has a descending aorta 22 , an aortic arch 24 and an ascending aorta 26 . A coronary artery 28 , in which a stenosis 30 has formed, starts from the ascending aorta 26 .

To the angioplasty catheter assembly 32 includes a guide catheter 34, a extending through the guide catheter 34 through guidewire 36 and a Dila tationskatheter 38 with an expandable balloon 40 which sits on a distal end 39 of a tubular main shaft 42 of the dilatation catheter 38th The dilatation catheter 38 is configured for use with a guidewire and has a guidewire lumen 45 ( FIGS. 2, 3 and 7) that extends its full length. An expansion lumen 47 also extends through the dilatation catheter 38 . The dilatation catheter 38 can be constructed as a double lumen or coaxial lumen arrangement. In a coaxial arrangement, as illustrated, the expansion lumen 47 is located between the outer main shaft 42 and an inner tubular shaft 41 , which sits coaxially within the outer shaft 42 . The guide wire lumen 45 is formed there by the interior of the inner tubular shaft.

As shown in FIG. 1, a proximal portion of the guidewire 36 protrudes proximally from a proximal end 43 of the dilatation catheter 38 , and a proximal portion of the dilatation catheter 38 protrudes proximally from a Y-adapter 37 that mates with a proximal end of the guide catheter 34 is connected. An expansion chamber 44 is connected to the proximal end 43 of the dilatation catheter 38 to allow the balloon 40 to expand. An expansion device 46 for expanding the balloon 40 is in flow connection with the balloon 40 via the expansion chamber 44 and the expansion lumen 47 .

The angioplasty procedure basically consists in that the guide catheter 34 is introduced into the vascular system 20 via the femoral artery. The guide catheter 34 is advanced through the vascular system 20 until the distal end of the guide catheter 34 lies adjacent to the mouth of the coronary artery 28 , as indicated in FIG. 1. Then, the distal end of the dilatation catheter 39 is slid over the proximal end 38 of the guidewire 36 and advanced over the guide wire 36 adjacent to the distal end 39 of the dilatation catheter 38 to the distal end of the guidewire 36 is located. The combination of guidewire 36 and dilatation catheter 38 is then inserted into the proximal end of the guiding catheter 34 and advanced in the distal direction therethrough, the arrangement following the path formed by the guiding catheter 34 through the patient's vascular system 20 . The combination of guidewire 35 and dilatation catheter 38 is typically advanced distally to near the distal end of the guiding catheter 34 . The distal tip of the guidewire 36 is then separately pushed and manipulated to get into the branch of the artery and through the stenosed artery. The dilatation catheter 38 is then advanced over the guidewire 36 to allow the balloon 40 to pass through the stenosis 30 . The balloon 40 is then expanded to provide for a dilatation of the nose 30 and again to allow an acceptable blood flow through the artery.

At times, however, the dilatation catheter 38 must be replaced with another dilatation catheter while the angioplasty procedure is being performed. When replacing the dilatation catheter 38 with another catheter, it is desirable that the guidewire 36 be held in a position to extend through the socket while the dilatation catheter 38 is withdrawn (and the next catheter is advanced) to avoid that the guidewire 36 must be threaded through the tortuous path up to the stenosis 30 after the dilatation catheter 38 is replaced. Leaving the guidewire 36 in place after an initial dilation also provides the physician with a path through the stenosis 30 in the event of an abrupt occlusion of the vessel.

The present invention allows the guidewire 36 to be left in a position passing through the socket 30 without the need for a replacement wire, an extension wire or additional intravascular devices to effect the dilatation catheter change over the guidewire 36 . In accordance with an embodiment of the present invention, an arrangement is provided proximal to the Y-adapter 37 of the guide catheter, which cooperates with the guide wire 36 to maintain the position of the guide wire 36 through the stenosis 30 . In this preferred embodiment of the invention, as is illustrated in FIGS . 2 to 7, a holding tool 50 is used which interacts with a functional segment 52 of the guide wire 36 in order to form a coupling force field between the tool 50 and the functional segment 52 . The coupling force field is an energy field (for example a magnetic field).

The force generated by the field is sufficiently high, the wire to the position of the guide maintain with respect to the tool 50 36 when the Dilatationska theter is aligned 38 with the function segment 52 of the guidewire 36, and particularly when the dilatation catheter 38 over the guidewire 36 is moved.

Accordingly, Fig. 2 is the functional segment of the guide wire 36 at egg nem proximal portion of the guidewire 36, and the location of the functional segment is selected such that the functional segment 52 is located at a certain distance beyond the proximal paint end of the Y adapter 37 of the guide catheter .

As is apparent from Fig. 3, 52 has the functional segment of the guide wire 36 includes a plurality of magnetically permeable segments 54 which are mounted on the guidewire 36 at locations along the guide wire 36. Examples of appropriate magnetic permeable materials are Rodar, manufactured by TN Wilbur B. Driver Company and available in tube form from the Uniform Tubes of Collegeville, PA, United States; Hiperco Alloy 50 , manufactured by Carpenter Steel of Reading, PA, United States; Permendur or 2V Permendur, which are highly permeable magnetic materials with large saturation flux densities in the CRC Handbook of Chemistry and Physics, 47 . Edition are listed; or any other material with a suitably large saturation induction. In this embodiment, as is shown in FIGS. 3 and 4, the functional segment 52 has a plurality of magnetically permeable segments 54 which are mounted around a part 57 of the guide wire 36 with a reduced diameter. Non-magnetically permeable segments 53 are located between the magnetically permeable segments 54 . In all embodiments of the functional segment 52 on the guide wire 36 , the outer diameter of the functional segment 52 remains essentially the same as the outer diameter of the guide wire 36 , and the transitions between the magnetically permeable and non-magnetically permeable materials are smooth.

According to FIGS. 5 to 7, the holding tool 50 on a housing portion 56. The housing part 56 is provided with a longitudinal slot 60 which is delimited by two slot side surfaces 62 and 64 and a slot bottom surface 66 . The slot 60 provides a space of sufficient size to slidably receive the dilatation catheter 38 and allow the dilatation catheter 38 to freely pass longitudinally through the slot 60 while restricting lateral movement of the dilatation catheter 38 between the slot surfaces 62 , 64 and 66 will.

The housing part 56 also has a plurality of rectangular magnetic sections 72 (indicated by dashed lines in FIG. 5), the surfaces of which are exposed on the slot bottom surface 66 . As best seen in FIG. 6, the magnetic portions 72 are longitudinally spaced apart along the housing part 56 according to the spacing of the magnetically permeable segments 54 on the guide wire 36 . The magnetically permeable segments 54 on the guide wire 36 and the magnetic portions 72 in the housing part 56 are spaced from one another such that they can be aligned with one another in the transverse direction, as can be seen from FIG. 3. Although the material of the Schlitzbo denfläche 66 changes alternately between the housing part material and the material of the magnetic portions 72, the slot bottom surface 66 is smooth. The magnetic portions 72 are preferably made of a strong magnetic material with high cohesive force (e.g. neodymium iron) that can maintain magnetization through a relatively thin portion.

The size and spacing of the magnetic portions 72 and the size and spacing of the magnetically permeable segments 54 of the functional segment 52 on the guidewire 36 are chosen to maximize the longitudinal attraction force on the guidewire 36 while the radial attraction force on the guidewire 36 mi is minimized. The resulting force to maintain the position of the guide wire 36 relative to the tool 50 is given by the equation

F _net = F _L -µF _R

determined where
F _{net is} the resulting force available to maintain the position of the guide wire 36 ,
F _{L is} the longitudinal attraction between the tool 50 and the functional segment 52 on the guide wire 36 ,
F _{R is} the radial force of attraction between the tool 50 and the functional segment 52 , and
µ is the coefficient of friction between the guidewire 36 and the dilatation catheter 38 .

In order to ensure optimum operating behavior of the device, it is desirable to maximize the force F _L and to minimize the force F _R and the coefficient of friction μ. The coefficient of friction µ can be reduced by using lubricant coatings and lubricants, while the attractive forces F _L and F _R can be optimized by using known mathematical model methods. For example, the arrangement of the magnetic sections 72 in the tool 50 reduces such that the polarity of the magnetic sections 72 alternates between the magnetic sections 72 , the radial attractive force F _R. The total coupling force between the functional segment 52 and the tool 50 is proportional to the number of magnetic sections 72 in the tool 50 .

In a preferred embodiment, the guide wire 36 has an outer diameter of 0.46 mm. The functional segment 52 has a length of approximately 25 cm with approximately 50 magnetically permeable segments 54 , each of which has a length of 2.5 mm and which are separated by means of non-magnetically permeable segments 53 with a length of 2.5 mm. An approximately 51 mm long non-operative segment is attached to the proximal end of the functional segment 52 . The tool 50 is approximately 100 mm long, 25 mm high and 25 mm wide, and it has 20 magnetic sections (magnets) 72 which are 5.1 mm apart. The magnetic sections 72 are 1 mm thick and 19 mm high; they have a width of 19 mm. The height and width of the magnetic portions 72 depends on the thickness of the magnetic portions 72 . The magnetic poles of the magnetic sections 72 alternate with one another, so that poles of the same name of the magnetic sections 72 arranged at a distance from one another are directed towards one another. The slot 60 for receiving the dilatation catheter 38 is 2.5 mm wide and 2.5 mm deep. Openings 68 which are provided centrally below each magneti rule section 72 (to the magnetic portions 72 glued during the assembly), have a diameter of about mm. 1

The device according to the invention for enabling dilatation catheter exchange while a guide wire is held in place in a vessel is used in the manner explained below. Such a change requires that the angioplasty catheter assembly 32 is already in place in the patient's vasculature 20 , as described above. The proximal end of the guide wire 36 and the proximal end 43 of the dilatation catheter 38 protrude proximally from the patient, as can be seen in FIG. 8. The proximal end of the guidewire 36 extends proximally beyond the proximal end 43 of the dilatation catheter 38 . The functional segment 52 of the guidewire 36 (indicated schematically by "xxx" in FIGS. 8 through 13) is located near the proximal part of the guidewire 36 , and it lies within the proximal end 43 of the dilatation catheter 38 . To initiate the exchange, the physician grips the proximal end of the guidewire 36 to hold the distal end of the guidewire so that it extends through the stenosis 30 . The doctor then applies a proximal portion of the dilatation catheter 38 (with the extending therein function segment 52) into the slot 60 of the housing part 56 (see Fig. 7 and 9), and it directs the functi onssegment 52 with the tool 50 from.

Aligning the functional segment 52 with the tool 50 is relatively simple because the functional segment 52 is longer than the slot 60 in the tool 50 and because the distance between the magnetically permeable segments 54 on the guide wire 36 and the corresponding magnetic portions 72 on the Tool 50 is relatively small. Therefore, when the functional segment is introduced 52 into the slot 60 of the tools and equipment 50, only a slight movement (less than half the distance between the magnetic portions 72 on the tool 50) is required to the magnetically active parts of the functional segment 52 and the tool 50 align with each other. If the distance between the magnetic sections 72 becomes smaller, less movement is sufficient to align the tool 50 and the function segment 52 . With the dimensions mentioned, the tool 50 and the functional segment 52 are practically self-aligning, and a simple insertion of the functional segment 52 into the slot 60 of the tool 50 is sufficient to ensure a suitable alignment.

After the functional segment 52 on the guide wire 36 is appropriately aligned with the magnetic sections 72 of the holding tool 50 , the guide wire 36 is attracted to the holding tool 50 by the resulting magnetic field formed between the two (see FIGS. 2, 3 and 7). As a result, the guide wire 36 (together with the dilatation catheter shafts 41 and 42 ) is pulled against the slot bottom surface 66 of the housing part 56 , as shown in FIGS. 3 and 7. The drawings are exaggerated in this regard for the sake of clarity.

After the guidewire 36 and tool 50 are coupled in this manner, the physician releases the guidewire 36 proximally from the tool 50 and then grips the proximal end 43 of the dilatation catheter 38 proximally from the tool 50 . The dilatation catheter 38 is pulled proximally over the guidewire 36 and past the tool 50 while the tool 50 (and thus the guidewire 36 ) is held in a stationary position with respect to the patient (see FIG. 10). The doctor can hold the tool 50 in his hand; instead, the doctor may place the tool 50 on the table to hold the tool 50 stationary. The longitudinal magnetic attraction between the guidewire 36 and the holding tool 50 is greater than the friction between the guidewire 36 and the inner catheter shaft 41 . Accordingly, the dilatation catheter 38 can be pulled over the guide wire 36 while the guide wire 36 is held in the same position with respect to the holding tool 50 . Since the guide wire 36 is held during this maneuver in a position in which it extends through the stenosis 30 , as long as the tool 50 is held substantially stationary with respect to the patient.

The catheter 38 is pulled until the distal end of the dilatation catheter 38 to be outside the patient's body comes (Fig. 11). A portion of the guidewire 36 is exposed between the distal end of the catheter 38 and the proximal end of the guiding catheter 34 , which protrudes from the patient's body. The doctor then grips this exposed portion of the guide wire 36 distally with respect to the tool 50 and the distal end of the dilatation catheter 38, for example at 76 . The doctor then separates the catheter 38 and the guide wire 36 located therein from the tool 50 in the transverse direction by overcoming the radial magnetic forces between the functional segment 52 of the guide wire and the tool 50 . The doctor then pulls the first balloon catheter 38 completely away from the guide wire 36 in the proximal direction. The guide wire 36 was thus kept in a substantially stationary position throughout the entire procedure of withdrawing the catheter in a very simple and elegant manner. This procedure can be performed by the physician without the need for assistants to hold or manipulate additional catheter or guidewire components.

While the guidewire 36 is held in place by gripping at 76 , a second dilatation catheter is placed on the proximal end of the guidewire 36 and advanced distally over the guidewire 36 until the functional segment 52 of the guidewire 36 is at a distal end of the second dilatation catheter (preferably in the second catheter at a location proximal to its balloon). The functional segment 52 of the guide wire 36 and the tool 50 are brought together (in the manner explained above) until the functional segment 52 is magnetically aligned with the magnetic sections 72 of the holding tool 50 . The doctor then releases the guide wire 36 di stally from the tool 50 (e.g., at 76 ), grips the second dilatation catheter, and pushes the second dilatation catheter longitudinally distally over the guide wire 36 with respect to the tool 50 and the guide wire 36 , thereby the second catheter is advanced through the guide catheter 34 in the distal direction. During the advancement of the dilatation catheter, the holding tool 50 is held stationary with respect to the patient in order to hold the distal end of the guidewire 36 in place in the stenosis 30 . The second Dilatationska theter is advanced in the distal direction over the guidewire 36, until the projecting le proxima end of the guidewire 36 over the proximal end of the second Dilatationskathe ters. The doctor then grasps the guidewire 36 proximally with respect to the tool 50 and the expansion chamber 44 of the catheter, and separates the second dilatation catheter and the guidewire 36 therein from the tool 50 . The second dilatation catheter is then advanced distally over the guide wire 36 until the balloon of the second dilatation catheter crosses the stenosis 30 for expansion. The replacement of the dilatation catheter can be repeated as often as necessary using the holding tool 50 and the functional segment 52 .

During the extraction and insertion of the dilatation catheter, the position of the guide wire 36 with respect to the guide catheter 34 and especially with respect to the stenosis 30 is maintained. The present device is particularly suitable for a catheter exchange without a long replacement guidewire, a modifi ed catheter or additional intravascular devices, for example a guidewire holding balloon for fixing the guidewire with respect to a wall of the guiding catheter, are necessary. The illustrated device allows catheter replacement over a standard length guidewire using a full length guidewire lumen catheter. The procedure can be carried out by a single doctor and does not require an extended x-ray examination to observe the position of the guidewire because the guidewire is held stationary by means of the device according to the invention and consequently its position need not be constantly monitored.

The use of the device explained is not limited to a catheter change. The device described can also be used, for example, as a "third hand" during catheterization. During a catheterization procedure, the doctor typically has to handle the guidewire 36 , the dilatation catheter 38 and the guiding catheter 34 simultaneously. The simultaneous manipulation often requires the use of medical assistants, which increases the cost and complexity of the procedure. By arranging the functional segment 52 adjacent to the tool 50 and by securing the tool 50 even in a stationary position, the doctor (or a second person) is relieved of the need to keep the guide wire 36 constantly during the procedure. The functional segment 52 on the guidewire 36 can be made long enough to use more than one tool 50 during catheterization. For example, if the physician pulls the dilatation catheter 38 out of the patient and must grip the guidewire 36 before the dilatation catheter 38 is fully removed from the guidewire 36 (e.g., if the physician grasps the guidewire 36 at 76 before the dilatation catheter 38 of the guidewire 36 is complete) is pulled down, as shown in FIGS. 11 and 12 shown and previously discussed), a second tool may be used 50 instead of the doctor itself engages the guide wire 36.

According to modified embodiments, the functional segment 52 on the guidewire 36 can take the forms illustrated in FIGS. 14, 15 and 21, among others. In the exemplary embodiment according to FIG. 14, a plurality of non-magnetically permeable segments 58 are fastened around parts 55 of the guide wire 36 A with a reduced diameter. The guide wire 36 A is made of a magnetically permeable material, while the segments 58 are made of a non-magnetically permeable material, for example plastics or non-magnetic metals. According to Fig. 15, the function of segment 52 have a Langge-stretched, non-magnetically permeable tubular member 51, 54 A are defined within which a plurality of solid cylindrical, magnetically permeable segments. The tubular component 51 is connected to a part 59 of the guide wire 36 B of reduced diameter. Another embodiment of the functional segment 52 has a guidewire segment that is made from a single material that can be in a magnetic or non-magnetic state depending on the heat treatment of the material (e.g., martensite or austenite steel). Alternating sections of the wire are then locally treated to obtain alternating magnetic and non-magnetic sections of the guidewire. In each embodiment of the functional segment 52 , the magnetically permeable material can be replaced by permanent magnets.

Functional segment 52 may also be formed on a short guidewire extension 74 (for example, about 300 mm long) for a standard guidewire. As shown schematically in Fig. 16, this short extension 74 would connect to the proximal end of the standard guidewire 76 in a conventional manner (see, for example, U.S. Patent No. 4,922,923, U.S. Patent No. 4,875,489, U.S. Patent No. 5,035,686 or U.S. Patent 5,117,838). The short extension 74 can be selectively attached to the standard guidewire 76 and can be repeatedly connected to and detached from the guidewire during a single intervention. The use of the short guidewire extension 74 with a functional segment 52 allows the physician to perform a catheter change of the type discussed herein even if the catheterization procedure was initiated using a standard guidewire 76 . The use of the short extension 74 when changing the catheter only makes it necessary to additionally attach the extension 74 to the guide wire 76 and to pull the original catheter out in the proximal direction far enough to cover the functional segment 52 on the short extension 74 before the dilatation catheter 38 is positioned relative to the magnetic coupling tool 50 between the elongated guidewire and the tool 50 . Otherwise, the use of such a short guide wire extension 74 corresponds either to holding the wire / catheter arrangement during the procedure or to enabling a catheter change over a stationary guide wire, essentially as described above.

Tool 50 can be designed to fit over guiding catheter 34 (as in a two-piece "conch shell"design); it can be formed in the form of a guide catheter extension; or it can, for example, be installed directly in the Y adapter 37 of the guide catheter. In addition, the tool 50 can be constructed such that the magnetic sections 72 located in the tool 50 can be adjusted within the housing part 56 and in particular can be moved away from the slot 60 in the housing part 56 . In this case, the attraction between the tool 50 and the functional segment 52 can be on the Füh approximately wire 36 effectively "turn off" when the magnetic sections 72 processing in the transverse direction sufficiently far from the slot 60 in the housing part 56 and the therein befind union function segment 52 of the guide wire 36 are moved away to cancel the magnetic attraction between them.

Another way to selectively make a magnetic field between the functional segment of the guide wire and the tool is to form the magnet of the tool as an electromagnet. As shown schematically in FIG. 17, a guidewire (or guidewire extension) 86 has a functional segment 52 (of the type discussed above), and in use, the guidewire 86 is inserted into a lumen of a catheter 88 . In this embodiment, a tool 90 is provided with an electromagnet 92 , which has selectively activated sections which are oriented in such a way that they interact with the functional segment 52 . The electromagnet is connected to a power source 94 via an ON / OFF switch 96 . By actuating the switch 96 , the application of current to the electromagnet 92 and thus the formation of a magnetic field by the electromagnet are controlled. The selectively activated sections within the tool 90 can be fed by mains current (alternating current) or rectified mains current (direct current). In one case as in the other, this current can be switched off by means of the switch 96 in order to interrupt the holding force between the tool 90 and the guide wire 86 .

The three main components of a modified embodiment of the tool are shown in the exploded view 100 in FIG. 18. A magnet mounting block 108 receives permanent magnets, not illustrated, in magnet receiving slots 104 in the manner explained above. The magnets are preferably arranged with alternating polarity in order to increase the effective axial holding force and to reduce the effective vertical force and thereby reduce the friction in the longitudinal direction. The magnet mounting block 108 preferably consists of a polycarbonate, for example from the material commercially available under the name General Elecric Lexan HP2X-42046. A floor block 102 is formed from a similar but clear material, for example from the material with the trade name General Electric Lexan HP2X-111, and it is in engagement with the magnetic mounting block 108 via a receiving channel 101 . In operation, the magnet mounting block 108 is held in the receiving channel 101 in that longitudinal projections 116 and 114 of the magnet mounting block 108 in the longitudinal channels 115 and 117 of the bottom block 102 fen eingrei. A correspondingly designed catheter receiving groove 118 stabilizes the position of the catheter arrangement in the manner described in more detail below.

A handle 111 is provided, which is formed, for example, from Lexan HP2X-111 (clear). The handle 111 has a catheter receiving element 112 and a correspondingly designed pawl 110 , which comes into firm engagement with a receiving groove 103 of the bottom block 102 and a receiving groove 105 of the magnetic mounting block 108 .

Fig. 19 shows a perspective assembly drawing of the modified form from FIG. 18 in operation. The catheter receiving element 112 is in sliding engagement with a Y adapter of a catheter arrangement 119 . The catheter arrangement 119 is stabilized in the catheter receiving groove 118 . The user appropriately summarizes the overall arrangement using the handle 111th

Fig. 20 shows a cross section of the assembled tool. Slants 120 and 122 guide the catheter arrangement 119 into the catheter receiving groove 118 , which is shaped in such a way that it holds the catheter arrangement 119 in the magnetic field explained above. In the illustrated embodiment, a permanent magnet 127 is held in place by contact with molded mandrels 129 a, 129 b and 129 c.

Fig. 21 shows a longitudinal section of a modified embodiment of the proximal end of a guide wire active region 126. An inner core 132 of the arrangement preferably consists of a wire made of Hyperco 50 B, which is an alloy of 48.5% cobalt, 48.5% iron and 3% vanadium. This alloy is commercially available and the wire has a diameter of approximately 0.28 mm.

The inner core 132 is ground on its circumferential surface in order to ensure a reduced diameter of approximately 0.114 mm over a distance of approximately 1.9 mm in regions 136 and 140 which are separated from one another by a likewise approximately 1.9 mm long path 138 . A proximal route 134 is approximately 256 mm long and a route 142 is approximately 12.7 mm long. The proximal end of a conventional spring coil guide (not shown for clarity) is butt welded to the distal end 144 of the inner core 132 .

The inner core 132 is coated with an adhesive, preferably the adhesive available under the trade name Hysol 9412, to fill the sanded areas 136 and 140 to a total depth in the unsanded areas of about 0.025 mm. The resulting assembly has a uniform outer diameter of about 0.28 mm, and a hypotube segment 128 made of 304 stainless steel is slipped onto this assembly before curing. The wall thickness of the hypotube segment 128 is selected so that in the finished state it will maintain a standard outer diameter which can be, for example, 0.46 or 0.36 mm. The hypotube segment 128 extends from the distal end 144 of the inner core 132 in the distal direction by at least 12.7 mm along an area 146 in order to relieve the stress on the butt weld at the distal end 144 . The proximal end 130 is ground in the form of a smooth hemisphere.

Fig. 22 shows another embodiment of the invention that allows the movement and direction of the guidewire to be measured, thereby providing the user with information regarding the position of the guidewire within the patient's body. A segment 212 of a guide wire 210 has, as can be seen from the longitudinal section, an area made of magnetic material 214 , which ensures a sequence of magnetic knots in the segment 212 . The material 214 can, for example, again be Hyperco 50 B, a material mentioned above in connection with the explanation of FIG. 20.

Corresponding to FIG. 22 are two electrical coils 222 and 224 in mutual Ab was arranged around the segment 214 around. The coils 222 and 224 are preferably at a distance such that a 90 ° phase shift with respect to the nodes of the material 214 is provided. The coil 222 is connected to an electrical circuit arrangement 226 , while the coil 224 is connected to an electrical circuit arrangement 228 . A generator that provides a signal of, for example, about 500 kHz is connected to the coils 222 and 224 . Corresponding to FIG. 22 of the Generator would be a part of the electrical circuits 226 and 228, although a single generator is provided in front of preferably.

If the guide wire 210 is adjusted in the longitudinal direction, there is a coupling between the magnetic material 214 and the coils 222 and 224 ; signals are generated in these coils. These signals go to circuitry 226 and 228 where they are amplified, filtered and preferably offset with respect to zero. The processed signals can then be reproduced in the manner illustrated in Figure 23. Instead, the processed signals from circuitry 226 and 228 can go to another electrical circuitry 230 . The circuit arrangement 230 , which is preferably a digital circuit, receives the signals from the circuit arrangements 226 and 228 and reproduces them in digital form.

Fig. 23 shows a graphical representation of the guidewire position versus inductance. A first sine wave 252 is based on the signals induced in the coil 222 , while a second sine wave 254 shown in dashed lines is based on the signals induced in the coil 224 . Because of the 90 ° phase shift, the viewer of the reproduction according to FIG. 23 can see in which longitudinal direction the segment 212 is adjusted. Because the distance between the nodes of the magnetic material 214 is known, the viewer of the reproduction according to FIG. 23 can also see how far the segment 212 and thus the guide wire 210 have been moved in the longitudinal direction.

Fig. 24 shows a further preferred embodiment of the measuring device according to the invention. A catheter 310 is connected to one end of a Y adapter 312 . Another catheter 315 is slidably guided at its distal end through the Y adapter 312 and into the catheter 310 . The catheter 315 extends through the center of a coil holder 320 to a point where the proximal end of the catheter 315 is connected to a catheter distributor piece 314 . A guide wire 310 can be passed through the distributor 314 and the Y-adapter as well as through both catheters 310 and 315 . The catheter 315 carries at its proximal end (not shown) a segment that is the same or similar to the segment 212 shown in FIG. 22 and that provides magnetic coupling to electrical coils (not shown) that are in the holder 320 are mounted in the manner explained above in connection with FIGS. 22 and 23.

The coils in the holder 320 are connected to electrical cables 322 and 324 , which in turn can be connected to an electrical circuit unit, for example the circuit arrangements 226 and 228 according to FIG. 22, in order to reproduce the example shown in FIG. 23 and above explained type of care. In the embodiment according to FIG. 24, the holder 320 is assigned to the guide wire 316 , and the reproduction represents the movement of the wire 316 along its longitudinal path. On the other hand, when a connection is made with the Y adapter 312 , the holder 320 is related onto the catheter 315 and the resulting rendering represents the longitudinal movement of the catheter 315 together with its internal guidewire 316 .

According to a further modified embodiment of the invention, the functional segment can be part of a device, for example in the form of a sleeve, which is pushed over the guide wire and arranged thereon. Referring to FIG. 25, a tube or sleeve 242 having a central lumen over a guide wire and pushed 240 mounted on the guide wire. The sectional view of a portion of the sleeve 242 illustrated in FIG. 26 indicates that the sleeve may, for example, carry a magnetically effective portion 246 embedded in a material 244 in a manner similar to that described above in connection with other embodiments is explained.

Other forms of coupling can also be used within the scope of the present invention forces are used. Instead of using permanent magnets or electromagnets, lets the coupling force field between the guide wire and the holding tool for example, by using electrostatic or electrical fields testify. In any case, the coupling force between the tool and the guide wire through the catheter body, and there is no contact between the tool and the guide wire.

Claims (39)

1. A device for use with a longitudinal lumen have the catheter, provided with an insertable into the lumen shaft and a housing that is designed so that it holds a proximal end of the catheter against lateral movement, characterized in that Housing has a Katheterauf receiving groove and means for generating a differential holding force is provided within the housing to prevent longitudinal movement of the shaft while allowing longitudinal movement of the catheter. 2. Device according to claim 1, characterized in that the shaft is a guide is a wire that has a functional part that is designed so that it is internal can slide half of the lumen. 3. Device according to claim 2, characterized in that the housing one elongated first block with a longitudinal channel therein and one elongated second block held in this channel, which with a Groove is provided, which is designed so that the catheter with the in the lumen slidably disposed guide wire, and that between which he Most and the second block at least one magnet is seated, so that the functional part of the guide wire by means of a magnetic field generated by the magnet can be held. 4. The device according to claim 3, characterized by a plurality of Ab stood from each other arranged magnets that are designed to be one A plurality of spaced apart, magnetically permeable Ab cut the functional part of the guide wire. 5. The device according to claim 4, characterized in that the polarity on one another other magnets change. 6. Apparatus according to claim 4 or 5, characterized in that between the Magnets essentially non-magnetic permeable material is provided. 7. The device according to claim 4 or 5, characterized in that between the magnetically permeable sections essentially non-magnetically permeable Material is provided.   8. Device according to one of claims 4 to 7, characterized in that the Magnets are permanent magnets. 9. Device according to one of the preceding claims, characterized in that a handle attached to the housing is provided. 10. The device according to claim 9, characterized in that the handle with a Provide a coupling piece for sliding attachment to the catheter assembly is. 11. Device for controlling the relative movement between a tube and a shaft slidably arranged in the tube, characterized by
a sleeve which has at least one magnetic part,
an arrangement for mounting the sleeve on the shaft, and
a motion actuator which has at least one further magnetic part for coupling with the magnetic part of the sleeve in order to adjust the shaft with respect to the tube. 12. The apparatus according to claim 11, characterized in that the tube is part of a Is catheter and the shaft is designed as a guide wire. 13. The apparatus according to claim 12, characterized in that the magnetic part the sleeve has a plurality of discrete magnetic segments. 14. Medical device with
a catheter,
a guidewire that is adjustably disposed within the catheter;
a sleeve disposed around the guide wire and having a magnetic segment; and
a tool for controlling the relative movement between the catheter and the guide wire, the tool being provided with a magnetic part for coupling with the magnetic segment. 15. The apparatus according to claim 14, characterized in that the sleeve in the we is substantially cylindrical and has a lumen for receiving the guide wire points.   16. The apparatus according to claim 15, characterized in that the magnetic Segment a plurality of units spaced apart has a magnetically permeable material. 17. Device with:
a housing for holding a catheter assembly against lateral movement; and
means for generating a differential holding force within the housing to prevent longitudinal movement of a first part of the catheter arrangement and to prevent longitudinal movement of a second part of the catheter arrangement. 18. The apparatus according to claim 17, characterized in that the housing is a Has catheter receiving groove. 19. The apparatus of claim 17 or 18, characterized by one on the Ge Fixed handle. 20. The apparatus according to claim 19, characterized in that the handle with a Provide a coupling piece for sliding attachment to the catheter assembly is. 21. Device according to one of claims 17 to 20 with a catheter arrangement, which one guide wire and one slidably arranged over the guide wire has th catheter. 22. The apparatus according to claim 21, characterized in that the guide wire has a distal end and a proximal end and the proximal end of the guide tion wire has an active area, which by means of the device on a Longitudinal movement is prevented. 23. An apparatus for use in measuring the relative longitudinal movement between a guidewire and a catheter member having a longitudinal lumen for slidably receiving the guidewire, the apparatus being provided with:
a magnetically active segment on the guidewire; and
an electrical coil assembly disposed around the magnetically active segment on the guidewire so that a magnetic force therebetween couples the coil assembly and the guidewire to provide signals indicative of the relative position and movement between the guidewire and the catheter member . 24. The device according to claim 23, characterized in that the electrical spu lenanordnung on at least two spaced coils points. 25. The apparatus according to claim 23 or 24, characterized in that the magne table active segment on the guide wire a linear sequence of magnetic Has knots. 26. Device according to claims 24 and 25, characterized in that the Ab there was a mutual phase shift of 90 ° between the two coils corresponds with respect to the magnetic nodes on the guidewire. 27. The device according to one of claims 23 to 26, characterized by a the electrical circuit arrangement connected to the coil arrangement for display of the signals. 28. The device according to one of claims 23 to 27, characterized in that the guidewire has a distal portion and a proximal portion indicates that the magnetically active segment is projected on the proximal portion hen and that the proximal portion selectively on the distal portion is feasible. 29. Device according to one of claims 23 to 28, characterized in that the magnetically active segment on the guide wire has at least one magnet ten. 30. Device according to one of claims 23 to 28, characterized in that magnetically permeable the magnetically active segment on the guide wire Has material. 31. An apparatus for use in selectively measuring the longitudinal movement of a guidewire and a first catheter over a second catheter having a longitudinal lumen for slidably receiving the guidewire and the first catheter, the first catheter having a further longitudinal lumen for slidably receiving the guidewire and the device is provided with:
a magnetically active segment on the guidewire;
an electrical coil assembly disposed around the magnetically active segment on the guidewire such that magnetic force therebetween couples the coil assembly and the guidewire to provide signals indicative of the position and movement of the guidewire;
a first support assembly for selectively supporting the coil assembly in fixed relationship with the first catheter to provide signals indicative of guidewire movement through the first catheter lumen; and
a second support assembly for selectively supporting the coil assembly in fixed relationship with the second catheter to provide signals indicative of movement of the first catheter through the second catheter lumen. 32. Apparatus according to claim 31, characterized in that the electrical spu lenanordnung on at least two spaced coils points. 33. Apparatus according to claim 32, characterized in that the two coils on a bracket with first and second connecting parts for engagement with the first and the second holding arrangement are mounted. 34. Device according to one of claims 31 to 33, characterized in that the magnetically active segment on the guide wire is a linear sequence of ma has genetic knots. 35. Apparatus according to claim 33 or 34, characterized in that the distance between the two coils a phase shift of 90 ° with respect to the corresponds to magnetic knots on the guide wire.   36. Device according to one of claims 31 to 35, characterized in that with the coil arrangement, an electrical circuit arrangement for displaying the Signals is connected. 37. Device according to one of claims 31 to 36, characterized in that the guidewire has a distal portion and a proximal portion indicates that the magnetically active segment is projected on the proximal section hen, and that the proximal portion selectively attaches to the distal portion is feasible. 38. Device according to one of claims 31 to 37, characterized in that the magnetically active segment on the guide wire has at least one magnet ten. 39. Device according to one of claims 31 to 37, characterized in that magnetically permeable the magnetically active segment on the guide wire Has material.