Nova Patents
ES2657019T3

Adaptive rotary catheter for opening obstructed bodily vessels

Abstract

A rotating catheter (10) to open an obstruction (11) in a body vessel (12), comprising in combination: a flexible hollow shaft (14) driven by motor and rotatably arranged in a flexible tube (13), a suction channel defined between an internal diameter of said flexible tube and an external diameter of said hollow axis, at least a portion being distal of said hollow shaft free to move radially in said aspiration channel which allows said aspiration channel to ingest particles that are so large or are smaller than a difference between said internal and external diameters; the relative movement between said rotating hollow shaft and said flexible tube facilitates the movement of the particles through said aspiration channel and prevents the particles from obstructing said aspiration channel, a tip (20), characterized in that it has a narrowed cross section wherein said tip is fixed to a distal end (39) of said hollow shaft, said tip having a rounded distal end (36), wherein the rounded distal end (36) of the tip (20) defines a hole (18) adapted to fit on a guide wire (15), said hollow shaft and said tip being able to rotate and slide on said guide wire, having said tip also a first side (22) opposite a second side (24), said first side being adapted to impact said obstruction when said tip rotates in a first direction (40), said first side (22) and said second side (24) being separated at a distance equal to a cross section (91) to define a width of said tip (20), said tip also has a base (26) and an opposite crown (27) which is adapted to slip atraumatically against a wall of said vessel as said tip rotates out of said flexible tube, said base (26) and said opposite crown (27) being separated from each other by a distance equal to the cross section (90) so as to define a height of said tip (20), said crown being displaced (89) away from to a longitudinal axis of said hollow axis in addition to said base being displaced (88) away from said longitudinal axis, said width being smaller than said height.

ES2657019T3, drawing sheet 1
Sheet 1 of 9

Term

5.9 yearsto projected expiry

Projected expiry 14 August 2032, counted from filing; an application has no term until it is granted.

  1. Priority
  2. Filed
  3. Published
  4. Today
  5. Projected expiry

31 paragraphs, as filed

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hole 14 when the catheter is folded.

However, if a particle of excessive size (which transversely measures more than the difference between the diameters 13id to 14od) enters and fits into the channel 87, the spiral wire 17 (if one is used) is preferably rotated in one direction which transports it distally to prevent said oversized particles from accumulating and obstructing the suction channel. This action can be reinforced by manufacturing the cross-section of the wire (with which the spiral wire is made) with small outer ridges 34 (see Figure 5). However, particles that are small enough not to fit into the channel 87 are practically unaffected by the small ridges 34 and are easily aspirated proximally, which is facilitated by the relative rotation of the hollow shaft 14 with respect to the tube flexible 13, which substantially reduces the frictional resistance to the movement of the particles through the channel 87; therefore, the relative rotating and radial movements, combined, between the hollow shaft and the flexible tube facilitates the movement of the particles towards and through the suction channel and prevents the particles from obstructing it.

It can also be seen that increasing the height 90 of the tip so that it fits snugly through the introducer reinforces the radial reach 89 of the tip and the cross-sectional area of ​​the tunnel that the tip opens through the obstruction (see Figure 3). Increasing the height of the tip 90 beyond the internal diameter 13id of the flexible tube (see Figure 8) allows the flexible tube to be advanced to the tip, but not above it. The height of the tip can be reduced so that it is slightly smaller than the internal diameter 13id, which allows the flexible tube to be advanced and protected (see Figures 10a, 10b). In this protected mode, the rotating catheter can easily aspirate soft obstructions that do not have to break before entering the flexible tube because the narrow cross section of the tip leaves the suction passages 22 'and 24' open between the sides 22 and 24 of the tip to the walls of the flexible tube, respectively. As the soft clogging material enters the passageways 22 'and 24' and is placed between the sides of the rotating tip and the walls of the flexible tube, the rotating tip macerates the clot so that it is easily aspirated along the entire length. inside the syringe 37. Similarly, the passages 22 'and 24' (see Figure 3) allow particles, such as those generated by the tip, to pass along the tip and be aspirated by the flexible tube 13 each time the tip You are working in a tunnel or a small vessel whose diameter is close to the height 90 of the tip.

Figure 11 shows a further modification in which the flexible tube 13 is terminated along a diagonal line 13 'so that when the cylinder 42 is partially removed from the housing, the flexible tube partially shields the tip. As one skilled in the art can understand, the length of the groove 47 can be adjusted to allow the flexible tube to move from a position of total protection to a position where the tip and a short section of the spiral are exposed. The configuration shown in Figure 11 allows the tip to be advanced and urged into contact with an asymmetric obstruction 11 ', which is located on one side of the vessel, while the flexible tube acts as a barrier between the tip and an opposite side of the glass. A radiopaque marker 19, attached to the walls of the flexible tube, can be used to help the user position the flexible tube with respect to the obstruction.

In Figure 12, a modification of the rotating catheter of Figure 11 is shown in which the distal end of a flexible tube 31 resembles a miniaturized shovel of a gardening shovel. The blade protects a certain length of one of the sides of the vessel walls against the rotating tip while pushing the rotating tip towards an asymmetric obstruction 11 'located on the opposite side of the wall. Figure 13 shows a blade 32 with a thicker bottom 33 to push the tip further towards the obstruction. The elongated shape of the blades 31 and 32 protects a length of the obstruction without repositioning the blade in the vessel.

Figure 1a shows the rotating catheter 10 with the flexible tube 13 slid distally, relative to the hollow shaft 14 and the tip 20, to reduce a gap between an edge 13e of the flexible tube and the tip. The reduced space prevents the edge 13e from engaging with the walls of the vessel 12. While the edge 13e is preferably rounded or chamfered (see Figure 8), the reduced gap further reduces the likelihood that the edge 13e scrapes the walls of the vessel 12 while the rotating catheter is advanced distally in the vessel.

While the present invention has been illustrated with a specific embodiment, it should be understood that modifications and substitutions can be made. For example, the hollow shaft portion 16 may constitute most or all of the hollow shaft 14. On the contrary, to reinforce the flexibility of the rotating catheter, the portion 17 (or a wire tube manufactured by Asahi Intecc Co., mentioned above) can be lengthened so as to constitute most or all of the length of the hollow shaft 14 . Another modification of the hollow shaft 14 consists in having a first portion of short proximal tube that is connected to a second portion of proximal spiral wire that is connected to a portion of distal tube that is connected to a fourth distal portion of spiral wire. Such a configuration may be useful in a longer rotating catheter necessary to reach the heart region from a typical vascular entry point in the groin region. In such an application, the proximal spiral wire portion provides a reinforced flexibility in the inlet region, while the distal portion of the spiral wire provides a necessary reinforced flexibility in the heart region while the third tube portion Proximal is flexible enough to be arranged in and between these regions (in the relatively straight aorta). A stepped construction of this type reduces the volume of the system and the longitudinal flexibility of the hollow shaft 14.

The sides 22 and 24 can be made slightly curved or inclined (see Figure 16) from the position

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parallel illustrated in Figure 3, so as to increase the passageways 22 'and 24' while narrowing the crown, or vice versa, it can be done so as to increase the crown to provide a larger support area for the tip as it slides on a wall of vessel 13.

The guidewire allows the rotating catheter to be supplied through a tortuous vasculature to remote occlusions and

5 operate it with an improved degree of security; however, a rotating catheter according to the present invention can be adapted to occasionally operate with the guide wire removed proximally in the hollow shaft to address specific clinical scenarios. One of these scenarios of adaptation of the rotating catheter to a total cross occlusion as previously analyzed. A second scenario refers to the treatment of large vessels (for example, blood vessels in the pelvic area, hemodialysis fistula, aneurysm) with a modified rotating catheter

10 shown in Figures 14-16. Figure 14 shows a distal end section of the spiral wire 17 extending outside the distal end of the flexible tube 13 that is straightened by a guide wire 15 that is disposed therethrough; however, the section of the distal end of the spiral wire is preformed to automatically adopt a curved shape when the guide wire 15 is removed from it (see Figure 15) and thus increase the displacement of the tip 20. This in turn substantially increases the area within the circle 29 '

fifteen that the tip sweeps (see Figure 15) compared to the area within circle 29 (see Figures 14 and 3). However, it should be understood that the actual cross-section of the tunnel that is opened by the tip will also be affected, for example, by the surrounding topography and the material of the vessel and obstruction and by the rotational speed of the hollow shaft and the tip . Therefore, when a larger segment of a vessel has to be treated, the guide wire can be removed proximally from the spiral wire, allowing the preformed distal end section

twenty of the spiral wire automatically adopt its preformed curved shape shown in Figure 15 and thereby increase the sweep of the tip. Optionally, the user can gradually remove the guide wire to achieve a corresponding gradual curvature of the section of the distal end of the spiral wire. After opening the large vessel, the guide wire can be advanced distally again through the section of the distal end of the spiral wire to redopt the configuration shown in Figure 14. After it has been

25 Using the rotating catheter, the guide wire can be left in the vessel for a follow-up procedure (for example, angioplasty and / or stenting).

Figure 16 is a cross-sectional view of a modified tip 20 ', along a plane 16-16 indicated in Figure 14. The tip has slightly curved sides and a reinforced offset 89 which is achieved by reducing the offset 88 and essentially using the spiral wire as a 26 'base.

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