AU621098B2 - Steerable guidewire for vascular system - Google Patents

Description

'C OPI DATE 25/08/89 v AOJP DATE 28/09/89 APPLN. ID 32161 89

PCT

PCT NUMBER PCT/US89/00343 INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (51) International Patent Classification 4 (11) Intf ti Pul ati fum WO 89/ 06985 A61M 25/00 Al (43) lnteAtilL Pub latiod fate 10 ust 1989 (10.08.89) (21) International Application Number: PCT/US89/00343 (81) Designated States: AT (European patent), AU, BE (European patent), CH (European patent), DE (Euro- (22) International Filing Date: 27 January 1989 (27,01.89) pean patent), FR (European patent), GB (European patent), IT (European patent), JP, LU (European patent), NL (European patent), SE (European patent).

(31) Priority Application Number: 148,906 (32) Priority Date: 27 January 1988 (27,01.88) Published With international search report.

(33) Priority Country: US (71)Applicant: ADVANCED BIOMEDICAL DEVICES, INC. [US/US]; One Launching Road, Andover, MA 08101 (US).

(72) Inventor: WINTERS, Edward One Launching Road, Andover, MA 08101 (US).

(74) Agents: BERNARD, Eugene, L. et al,; Bernard, Rothwell Brown, 1700 K Street NW, Suite 800, Washington, DC 20006 (US).

(54)Title: STEERABLE GUIDEWIRE FOR VASCULAR SYSTEM (57) Abstract A guidewire arranged to be transported through the vascular system composed of a helically wound tapered spring a length of tubing (14) attached to the proximal end of the spring, a wire (16) attached to the inner surface of and extending to the tip (12) of the spring for curving the tip (12) to a desired shape, and a tapered core wire (18) movably disposed in the tubing (14) and spring (10) and of sufficient length to extend to the tip (12) of the spring (10) to vary the -tiff.

ness and curvature of the tip (12) WO 89/06985 PCT/US89/00343 1 Steerable Guidewire for Vascular System Background of the Invention Field of Invention The invention is related to guidewires used for the insertion of catheters into the vascular system as a method of treating coronary arterial vascular blockage.

Description of the Background Art As a creatment technique for removing blockages in the vascular system, particularly those which affect the blood supply to the heart, guidewires of very fine diameter are inserted directly into the system from outside the patient and manipulated or steered by the physician or practitioner through the system to the blockage by fluoroscopic observation. Since the various arteries through which the wire must pass are sinuous or irregular in shape and intersect and connect with other vessels at various and sometimes sharp angles, maneuvering the wire to the position of concern is a delicate task. A plurality of quidewire type devices designed for this purpose exist in the prior art.

Each is a novel approach to the problem of providing the user with sufficient control to transverse the vascular system in a speedy and careful manner.

For example, United States Patents 4,545,390, Leary, and 3,789,841, Antoshkiw, both show distal tips formed of helically wound springs surrounding fixed tapered cores.

3,631,848, Muller, describes an axially movable distal tip extension tube of relatively short length.

44 I U.S. Patent No. 4,676,249 discloses a guidewire having a coil spring with a bendable tip of constant diameter, with a core wire movable therein.

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I 2 A coil tip with tapered face edges which will curve toward the taper when pulled upon by an internal control wire is disclosed in 3,452,740 and 3,452,742, both to Muller. 4,650,467, Bonello, shows a sinilr arrangement for inclining the tip by retraction of a control wire affixed thereto.

Additionally, 3,528,406, Jeckel et al., teaches the use of a fixed core wire having a reduced diameter in the spring tip portion of the wire. 3,625,200, Muller, discloses a curvable tip comprising solid cylindrical links engaging each other with ball and socket joints each of which is manipulatable by a fine core wire.

Finally, 4,573,470, Samson, shows a curved tip which is rotated in its entirety by rotating a core wire at the control handle.

The present invention is an improved guidewire which allows the user to vary the stiffness of the wire and vary the curvature of the tip from outside the patient during the transport and manipulation process.

Summary of the Invention A steerable guidewire arranged to be transported through a patient's vascular system is provided, of the type having a helically wound spring (10) terminating at a distal end thereof in a smooth rounded tip (12) and a core wire (18) movably disposed within said spring whereby the distal end of said spring (10) will be variably stiffened and straightened according to the position of said core wire (18) within said spring. The invention is characterized in that the distal end of said spring (10) is tapered, a length of tubing (14) is attached to a proximal end of said spring and a safety wire (16) is disposed within and connected to the inner surface of said spring Safety wire (16) 3 extends to the tip (12) of said spring said wire (16) having sufficient rigidity to allow said spring to be curved at its distal end. The core wire (18) has a tapered distal end which is complementarily receivable within the tapered distal end of said spring with the tapered core wire (18) being simultaneously movable within said tubing (14) and said spring The distal end of the core wire (18) has a tip arranged to be extended to the inner tip of said spring Brief Description of the Drawinqs Fig. 1 is a cross sectional view of the preferred embodiment; Fig. 2 is an additional cross sectional view of the embodiment of Fig. 1, and Fig. 3 is a further cross sectional view of the preferred embodiment, Description of the Preferred Embodiment Referring to Fig. I there is shown a cross sectional view of the steerable guidewire which comprises hhe preferred embodiment of the invention. Helically wound spring 10 composing the distal portion of the wire is tapered outward from tip 12 toward tubing 14. The amount or angle of taper and correspondingly the length of the coil are a matter of choice as dictated by clinical requirements. A coil length of 30 centimeters has been found appropriate and as will be obvious, the proximal portion of the coil may have little or no taper, the critical region being that nearest the tip. In the illustrated embodiment, the coil is uniformly tapered.

A safety wire 16 which has sufficient rigidity to hold an imparted shape is attached to the inner surface of spring 10 to provide bias for curving the tip and to prevent the coils of the spring from stretching apart 4 d

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V* t~ WO 89/06985 PCT/fUS89/00343 4 upon retraction. Tapered core wire 18 is disposed within spring 10 and tubing 14 and extends as does tubing 14 a selected length to allow the user to place the core wire at various positions within the spring from outside the patient. A length of approximately 150 centimeters has been found appropriate for this purpose.

Figs. 2 and 3 show the attitude that the tip will assume when the core is partially withdrawn. Fig. 2 illustrates the partial curve of the tip, the core still acting in part to counter the bias of wire 16 and Fig. 3 shows the core sufficiently withdrawn to allow the tip to reach its full bent, which, according to the illustrated embodiment, is the tip portion shown in Fig. 3. As can be seen in Fig. 3, the helically wound spring 10 is tapered along the entire length of the curved portion thereof when the tip is in the full bent position shown in Fig. 3.

As is now evident, the invention disclosed herein allows a range of flexibility and control previously unavailable in the art. The wire may be varied from a straight still configuration for penetrating or crossing lesions to a curved flexible profile of infinitely varying degree for steering through the junctions, twists and turns of the vascular system.

The materials of which the invention is constructed as well as the technique of use of the wire once in place to receive a catheter are well known and thus not herein described in detail. Similarly the control handle for holding the tubing and moving the core at the proximal end is a device of simple construction of the type described in the prior art referenced above.

Accordingly, the invenL2.on is defined by the following claim.

Claims (4)

1. A steerable guidewire arranged to be transported through a patient's vascular system comprising a helically wound spring terminating at a distal end thereof in a smooth rounded tip and a core wire movably disposed within said spring, characterized in that the distal end of said spring Is tapered, a length of tubing is attached to a proximal end of said spring, a safety wire is disposed within and connected to the inner surface of said spring, said safety wire extending to the tip of said spring, said safety wire having sufficient rigidity to cause said spring to be curved at its distal end, and said 10 core wire having a tapered distal end which is complementarily receivable within the tapered distal end of said spring, the tapered core wire being simultaneously movable within said tubing and said spring; the distal end of the core wire having a tip arranged to be extended to the inner tip of said Sspring; said core wire having sufficient rigidity to cause the guidewire to S 15 have a substantially straight still configuration when said tip of the core wire is extended to the inner tip of said spring. I

2. The guidewire of claim I wherein said spring is uniformly tapered, and said safety wire is biased and has sufficient rigidity and bias to cause said spring to be curved at Its dislal end between a full bent position thereof and a substantially straight position thereof, wherein the helically wound spring is tapered along the entire length of the curved portion of the spring when 4/ the distal end thereof is in said full bent position.

3. The guidewire of claim 1 wherein the tapered spring is about 30cm In mwspe#5914 91 12 3 -A -6- length.

4. The guidewire according to any one of claim 1 to 3 substantially as hereinbefore described. DATED this 3 December 199.1 CARTER SMITH BEADLE Fellows Institute of Patent Attorneys of Australia Patent Attorneys for the Applicant: ADVANCED BIOMED ICAL DEVICES, INC, fT mwspe#59149123 91 12 3