US20070142856A1 - Convertible mode vascular catheter system - Google Patents

Abstract

An angioplasty catheter comprising a catheter shaft having a proximal portion and a distal end, an angioplasty balloon attached to the shaft at the distal end, a balloon inflation lumen extending through the shaft and communicating with the interior of the balloon, a guidewire lumen extending through the shaft and through the balloon for receiving a steerable guidewire, the guidewire lumen having an outside wall, wherein the guidewire lumen has a proximal opening located at a point normally outside of the patient during use of the catheter for insertion of a guidewire into the lumen, and a side port adapted to permit passage of a guidewire into the lumen through the outside wall of the guidewire lumen, the side port located distally of the proximal opening and at a point normally inside of the patient during use, and guidewire removing means in the outside wall of the guidewire lumen extending from the proximal opening to the side port for permitting a guidewire in the guidewire lumen to be moved laterally from the guidewire lumen through the outside wall of the guidewire lumen. Also disclosed are a removable “Y” connector and methods for using the catheter and for exchanging catheters and guidewires during vascular catheterization procedures.

Description

RELATED APPLICATIONS
• This application is a continuation of application Ser. No. 10/282,687 filed Oct. 28, 2002, which is a continuation of application Ser. No. 07/714,642 filed Jun. 13, 1991, the disclosures of which are hereby incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
• This invention relates to vascular catheters (such as angioplasty catheters) specially adapted for rapid-exchange of both the guidewire and the catheter during use. It also relates to the method of using those catheters.
• Percutaneous transluminal coronary angioplasty (PTCA) has emerged as the major viable present alternative to bypass surgery for revascularization of stenotic and occluded coronary arteries. Although transluminal angioplasty has application in peripheral artery disease, it is most widely used in the treatment of coronary artery disease. Unlike bypass surgery, percutaneous angioplasty does not require general anesthesia, cutting of the chest wall, extracorporeal perfusion, or transfusion of blood. Percutaneous coronary angioplasty is not only less invasive and less traumatic to the patient, it is also less expensive because the angioplasty patient will have a shorter hospital stay and shorter post-procedure recovery time.
• Percutaneous transluminal angioplasty is performed by making a skin puncture with a specially-designed needle in one of the groins, and then introducing a guiding catheter (typically 8 or 9 French size) into the aorta and coronary artery orifice. A smaller caliber catheter which has a built-in inflatable and deflatable balloon of predetermined size and diameter is passed through the guiding catheter which is positioned in the opening of a target artery. This balloon catheter (with the balloon totally deflated by negative pressure) is advanced inside the target artery toward the point of obstruction that needs to be dilated. The guidewire plays an essential role in leading the balloon catheter to the target coronary artery in safety and non-traumatic fashion. With the balloon portion of the catheter properly positioned inside the obstructed segment of the artery, under X-ray fluoroscopic observation, the balloon is inflated by injecting contrast media mixed with saline at a pressure sufficient to overcome the resistance of the arteriosclerotic plaque of the obstructed segment.
• By inflating the balloon in the stenosis multiple times over a period of between 10-30 seconds and one or two minutes (allowing blood flow between inflations), the desired dilation of the obstructed segment of the artery can be achieved. When the desired results have been obtained by balloon inflations, the guiding catheter, the balloon catheter (with the balloon completely deflated with negative pressure) and the guidewire are withdrawn from the artery and the patient and the procedure is successfully terminated.
• The size and diameter of the balloon to be used in a transluminal angioplasty should be approximately matched to the size and native diameter of the obstructed segment of the artery to be dilated. If the balloon size and diameter is smaller than the native artery, the results of balloon angioplasty are suboptimal, requiring a second dilation with a larger-sized balloon, and if balloon size is too large for the native artery, complications may occur due to arterial wall damage.
• During the angioplasty procedure, a guidewire is first advanced into the desired location, after which the angioplasty catheter is advanced over the guidewire. It is sometimes necessary to replace (or exchange) either the guidewire or the balloon catheter during the procedure.
• If the balloon is undersized, for example, the catheter must be withdrawn and replaced with a larger balloon catheter in order to permit adequate dilatation of the lesion. With conventional over-the-wire catheters, in which the guidewire lumen extends the entire length of the catheter shaft, a guidewire extension (e.g., 145 cm long) must first be attached to the regular guidewire (e.g., 175 cm long) being used outside the patient before the catheter is withdrawn. This permits the distal end of guidewire to be held in position while the catheter is removed and a new catheter is exchanged. Usually, two to three operators are needed to effect such a catheter exchange.
• The catheter disclosed in U.S. Pat. No. 4,762,129 avoids the necessity for extending the guidewire or exchange guidewire (e.g., 300 cm in length) by having a short guidewire lumen that extends substantially only through the distal end of the catheter. This type of catheter is referred to herein as a rapid-exchange catheter. Thus, the guidewire is outside the catheter shaft for much of the catheter length, and is inside the catheter at only the distal end. The catheter can be exchanged without extending the 175 cm regular guidewire, and the exchange can be effected by one or two operators. However, this catheter has a serious drawback of not being able to permit ready exchange of guidewires. In clinical practice, the need for guidewire exchange is more common.
• Conventional over-the-wire angioplasty catheters, with a guidewire lumen extending their entire length, permit simple guidewire exchange. During angioplasty procedures, the guidewire tip may become damaged, may be needed of a different type of guidewire or may need to be reshaped to complement the patient's vasculature. The guidewire exchange procedure is readily accomplished with such a conventional over-the-wire catheter. However, with the rapid-exchange type catheter of U.S. Pat. No. 4,762,129, guidewire exchange requires complete removal and reinsertion of both the guidewire and the angioplasty catheter; thus, defeating the original goal of expedient advantage of the rapid-exchange catheter.
• Another disadvantage of the rapid-exchange catheter is backbleeding. While the guidewire is being manipulated to select the target vessel or to cross the culprit lesion, the Tuehy-Borst adapter must be loosened. This, in turn, permits backbleeding to occur.
• Accordingly, there is a need for an angioplasty catheter that permits rapid-exchange of both the catheter and the guidewire. There is also a need for a catheter that will permit the user to select the mode of usage between the rapid-exchange and the over-the-wire systems.
BRIEF SUMMARY OF THE INVENTION
• In accordance with one aspect of the present invention, there is provided an angioplasty catheter comprising a catheter shaft having a proximal portion and a distal end, an angioplasty balloon attached to the shaft at the distal end, a balloon inflation lumen extending through the shaft and communicating with the interior of the balloon, a guidewire lumen extending through the shaft and through the balloon for receiving a steerable guidewire, the guidewire lumen having an outside wall, wherein the guidewire lumen has a proximal opening located at a point normally outside of the patient during use of the catheter for insertion of a guidewire into the lumen, and a side port adapted to permit passage of a guidewire into the lumen through the outside wall of the guidewire lumen, the side port located distally of the proximal opening and at a point normally inside of the patient during use, and guidewire removing means in the outside wall of the guidewire lumen extending from the proximal opening to the side port for permitting a guidewire in the guidewire lumen to be moved laterally from the guidewire lumen though the outside wall of the guidewire lumen. In one embodiment, the side port is located adjacent to and proximally of the balloon, preferably within about 35 cm of the balloon. One embodiment of the guidewire removing means is a slit through the outside wall of the catheter shaft. This slit may be continuous from the proximal opening to the side port, or may be discontinuous, forming a perforated line from the proximal opening to the side port. In another embodiment, the guidewire removing means is a weakened area of the wall of the guidewire lumen adapted to be severed for removal of the guidewire therethrough. One variation of the invention provides a second side port communicating with the interior of the guidewire lumen. Another provides a perfusion opening communicating with the interior of the guidewire lumen, the perfusion opening located between the side port and the balloon. Still another embodiment includes a “Y” connector at the proximal opening having an axial portion through which the balloon inflation lumen extends and a side portion through which the guidewire may be inserted into the guidewire lumen, wherein at least a portion of the connector can be removed from the catheter shaft to permit a guidewire extending through the connector and into the guidewire lumen to be removed through the guidewire removing means. The connector is advantageously adapted to be separated longitudinally and at least a portion thereof removed from the catheter shaft. In one variation, the connector comprises two longitudinally separable portions having first and second longitudinal sides on different sides of the catheter shaft, the portions being hingedly joined at the first longitudinal side and separably joined at the second longitudinal side.
• Another embodiment of the present invention comprises an intravascular catheter comprising a catheter shaft having a proximal end and a distal end, wherein a portion of the catheter including the distal end is normally inside a patient during use and the proximal end is normally outside the patient or outside the guiding catheter, a guidewire lumen extending through the shaft for receiving a steerable guidewire, wherein the guidewire lumen has an outside wall, and a proximal opening at the proximal end of the shaft for insertion of a guidewire into the lumen, and means formed in the outside wall of the guidewire lumen extending distally from the proximal opening to a point normally inside the patient during use of the catheter for permitting a guidewire in the guidewire lumen to be moved laterally from the guidewire lumen through the outside wall of the guidewire lumen. The guidewire removing means may be a slit, fully formed or inchoate. The catheter preferably includes a side port through the outside wall of the guidewire lumen for passage of a guidewire into the lumen through the side of the catheter shaft, the side port located distally of the proximal opening and normally inside of a patient during use of the catheter. In one embodiment of the catheter, the guidewire removing means is a slit and the slit is continuous from the proximal opening to the side port. In another, the guidewire removing means is a slit and the slit is discontinuous, forming a perforated line from the proximal opening to the side port. In still another embodiment, the guidewire removing means is a weakened area of the wall of the guidewire lumen adapted to be severed for removal of the guidewire therethrough. According to one modification, the catheter may further comprise a second side port communicating with the interior of the guidewire lumen.
• The present invention also includes a catheter for use in an animal body with a guidewire, comprising a catheter shaft having a proximal end and a distal end with at least two lumens extending therethrough, and a “Y” connector surrounding at least a portion of the proximal end of the catheter shaft and having at least two arms, one arm providing an access channel into one of the lumens and another arm providing an access channel into another of the lumens, wherein the “Y” connector has at. least two segments joined together in a separable manner along a longitudinal line so that upon separation of the segments, the “Y” connector no longer surrounds the portion of the proximal end of the catheter shaft. In one embodiment, upon separation of the segments, one of the segments is completely removable from the catheter shaft. In another embodiment, upon separation of the segments, the connector is completely removable from the catheter shaft in such a manner that an elongate object extending through one arm of the connector into a lumen of the catheter shaft can remain in the lumen during such removal of the connector.
• The invention further includes a method of removing a catheter during a procedure involving vascular catheterization, comprising the steps of providing a catheter of the type described above having a guidewire passing through the guidewire lumen from the proximal opening to the distal opening thereof and positioning the catheter in a patient with the proximal end of the guidewire extending out of the proximal opening, holding the proximal end of the guidewire to maintain the positioning of the guidewire in the patient while removing the catheter from the patient by moving the guidewire laterally out of the guidewire lumen through the guidewire removing means until the entire catheter is outside the patient and outside the guiding catheter and a portion of the guidewire is exposed at the distal end of the catheter, and then holding the exposed portion of the guidewire and removing the catheter off of the proximal end of the guidewire. The method may also include inserting another catheter, with the guidewire in the guidewire lumen at the distal portion of the catheter and either remaining in the guidewire lumen for the entire length of the catheter that is inside the patient during use, or extending out through the side of the catheter and running parallel to the catheter proximal of the distal portion of the catheter.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
• FIG. 1 is a foreshortened plan view of a catheter according to the present invention.
• FIG. 1A is a transverse cross section of the catheter ofFIG. 1, taken along the line A-A.
• FIG. 1B is a transverse cross section of the catheter ofFIG. 1, taken along the line B-B.
• FIG. 1C is a transverse cross section of the catheter ofFIG. 1 corresponding toFIG. 1B, but illustrating the opening of the guidewire removing means.
• FIG. 2 is a fragmentary view of a portion of the catheter shaft of theFIG. 1 catheter surrounding the proximal opening, illustrating one variation of the guidewire removing means.
• FIG. 3 is a longitudinal cross section of the catheter ofFIG. 1 taken along the line3-3, illustrating the guidewire in place and the function of the guidewire removing means.
• FIG. 4 is a cross sectional fragmentary perspective view of the catheter ofFIG. 1, taken along the line B-B, illustrating another variation of the guidewire removing means.
• FIG. 5 is a longitudinal cross section corresponding toFIG. 3, illustrating movement of the guidewire laterally out of the guidewire removing means.
• FIG. 6 is a foreshortened longitudinal cross section of the proximal end of one embodiment of the catheter of the present invention.
• FIG. 7 is a perspective view of a removable “Y” connector at the proximal end of the catheter shaft.
• FIG. 8 is a detailed perspective view of a locking mechanism on the “Y” connector ofFIG. 7.
• FIG. 9 is a transverse cross section taken along the line9-9 inFIG. 7.
• FIG. 10 is a detailed perspective view of another locking mechanism on the “Y” connector ofFIG. 7.
• FIG. 11 is an exploded transverse cross section corresponding toFIG. 9, illustrating removal of the “Y” connector from the catheter shaft.
• FIG. 12 is a perspective view of the distal end of the catheter shaft after removal of the “Y” connector, illustrating a sealing member.
• FIG. 13 is a longitudinal cross section of the removable “Y” connector, taken along the line13-13 inFIG. 7.
• FIG. 14 is a longitudinal cross section of the entire catheter, taken along the line13-13 inFIG. 7.
• FIG. 15 corresponds toFIG. 14, except that the guidewire is illustrated in place in the guidewire lumen.
• The foregoing summary, as well as the following detailed description of the preferred embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the preferred embodiments of the present invention, there is shown in the drawings, embodiments which are presently preferred. It should be understood, however, that the present invention is not limited to the arrangements and instrumentality shown in the attached drawings.
DETAILED DESCRIPTION OF THE INVENTION
• A basic embodiment of the catheter of the present invention is illustrated inFIG. 1. Acatheter10 is provided with acatheter shaft12 extending from aproximal end14 to adistal end16. As shown more clearly inFIG. 1B, the interior of thecatheter shaft12 has aguidewire lumen20 and aballoon inflation lumen22 extending through thecatheter shaft12.
• Thecatheter10 has anangioplasty balloon24 at thedistal end16 thereof. At theproximal end14 of thecatheter shaft12, aballoon inflation connector26 is provided in fluid communication with theballoon lumen22. Fluid introduced into the proximal end of theballoon inflation connector26 can travel through theballoon lumen22 and into the interior of theballoon24 to inflate and deflate theballoon24 during an angioplasty procedure. Theballoon inflation lumen22 terminates inside theballoon24. The opposite end of theballoon inflation lumen22 terminates inside theballoon inflation connector26.
• Theguidewire lumen20 is adapted to receive a steerable guidewire and has an outside wall30 (shown inFIG. 1B).
• Aproximal opening32 is provided through theoutside wall30 of theguidewire lumen20. Thisproximal opening32 is situated in the proximal portion of thecatheter shaft12 at a location sufficiently close to theproximal end14 that it is normally outside of the patient during the angioplasty (or other vascular procedure). Typically, theproximal opening32 will be within 60 cm, preferably within about 40 cm, more preferable within about 30 cm of theproximal end14 of thecatheter10.
• Theballoon24 is made in accordance with conventional techniques for fabricating angioplasty balloons. Preferably, it is either blown from thedistal end16 of thecatheter shaft12, or is blown or formed of a separate piece of material which is bonded to the distal end of16 of thecatheter shaft12. Theballoon24 may advantageously be formed of relative inelastic polymer material, such as polyethylene, polypropylene, polyvinylchloride, polyethylene terephthalate, and the like.
• Thecatheter shaft12 is also provided with aside port34 which extends through theoutside wall30 of theguidewire lumen20. Theside port34 is located distally of theproximal opening32, and is located at a point normally inside of the patient when the catheter is properly placed for performance of an angioplasty procedure. Preferably, theside port34 is located proximally of theballoon24 and within 80 cm, preferably 60 cm, and more preferably about 40 cm of theballoon24.
• Thecatheter10 of the present invention is provided with a means for removing a guidewire that is inside of the guidewire lumen out of theguidewire lumen20 through theoutside wall30 of theguidewire lumen20. If thecatheter shaft12 or the guidewire is considered to extend in a longitudinal or axial direction, this movement of the guidewire out of theguidewire lumen20 can be considered as a sideways, radial, or transverse motion of the guidewire. Theguidewire removing means40 is adapted to form a slit through theoutside wall30 of theguidewire lumen20 through which the guidewire may be removed from inside theguidewire lumen20. The guidewire removing means40 may be an actual slit cut entirely through theside wall30 of theguidewire lumen20 as illustrated inFIG. 1C. Alternatively, it may an inchoate slit such as the weakened area illustrated inFIG. 1B. The guidewire removing means40 may be cut entirely through theoutside wall30 of theguidewire lumen20 only in certain sections, leaving other sections at least partially intact, to form a sort of perforated line. It may be formed of a different material than the remainder of thecatheter shaft12 and even of a different material than the adjacent portions of theoutside wall30 of theguidewire lumen20.
• One advantage of having only an inchoate slit is that it prevents backbleeding out of the guidewire removing means40 during performance of the procedure. It is possible, however, to use an inchoate slit for only the portion of the guidewire removing means40 that is outside of the guiding catheter in use. The remainder of the guidewire removing means40 that is outside the patient and outside the guiding catheter can be a fully formed slit or a perforated slit without creating backbleeding problems.
• As illustrated inFIG. 2, the guidewire removing means40 may comprise aremovable tear strip42 defined by a pair of weakenedlines44,46 extending distally from theproximal opening32.
• Theguidewire removing means40 extends from theproximal opening32 distally along the length of thecatheter shaft12 to a point that is ordinarily inside the patient when thecatheter10 is properly placed for performance of an angioplasty procedure. Thus, theguidewire removing means40 begins at a point ordinarily outside the patient and outside the guiding catheter upon proper placement of thecatheter10 and extends distally to a point ordinarily inside the patient upon such placement. From another perspective, it can be said that theguidewire removing means40 extends distally for at least 40 cm, preferably at least 60 or 70 cm, and more preferably at least 80, 90 or 100 cm.
• The guidewire removing means40 may advantageously extend distally to theside port34, and in one embodiment of the invention, may extend an additional distance distally beyond theside port34. The guidewire removing means40 preferably terminates proximally of theballoon24, and may be immediately adjacent theballoon24 or may be 5 cm, 10 cm, or more proximally of theballoon24.
• If theguidewire removing means40 is not a slit prior to its use, it becomes a slit or opening after use, as illustrated inFIG. 1C.
• The use of thecatheter10 of the present invention is illustrated inFIG. 3. In this longitudinal cross sectional view, thecatheter10 is illustrated with aguidewire50 in place in theguidewire lumen20. The proximal portion of theguidewire50 is outside of thecatheter10. The guidewire50 passes through theproximal opening32 into theguidewire lumen20, and is inside theguidewire lumen20 for the entire length of thecatheter shaft12 that extends distally from theproximal opening32. The distal end of theguidewire50 extends out of thedistal end16 of thecatheter shaft12.
• When the guide wire is to be removed radially or laterally out of theguidewire lumen20, theguidewire removing means40 provides a slit or opening in theoutside wall30 of theguidewire lumen20 through which theguidewire50 may be removed from theguidewire lumen20. This slit or opening, if not fully formed, may be completed by cutting theoutside wall30 of theguidewire lumen20, by tearing or rupturing a weakened area in theoutside wall30, or by tearing loose a removable strip (as illustrated inFIG. 2). In a preferred embodiment theguidewire removing means40 is a weakened area that is fully opened only when theguidewire50 is removed through theguidewire removing means40. In one embodiment, theguidewire50 is simply pulled through theoutside wall30 of theguidewire lumen20. Alternatively, as illustrated inFIG. 4, thecatheter shaft12 may be provided with afilament52 in association with theguidewire removing means40. Thefilament52 may be a continuous fiber or strand extending along the length of the guidewire removing means and inside at least a portion of theoutside wall30 of theguidewire lumen20. When thefilament52 is pulled outwardly, it tears a slit into theoutside wall30 of theguidewire lumen20.
• InFIG. 3, the initial removal of theguidewire50 through theguidewire removing mans40 is illustrated in phantom. In that figure, aphantom guidewire50 is illustrated extending through theoutside wall30 of theguidewire lumen20 at a point distally of theproximal opening32.
• As illustrated inFIG. 5, the phantom guidewire50 is pulled through theoutside wall30 of theguidewire lumen20 until theguidewire50 has been removed through theoutside wall30 up to theside port32. It will be understood, of course, that in accordance with the present invention, theguidewire50 may be removed through theoutside wall30 to a point proximal of or distal of theside port34; however, in a preferred embodiment, the lateral removal out of theguidewire lumen20 continues up to theside port34.
• It should be noted that the removal of the proximal portion of theguidewire50 through theoutside wall30 can be accomplished without longitudinal or axial movement of the distal portion of theguidewire50. Thus, inFIG. 3, the distal tip of theguidewire50 is in the same position as inFIG. 5; however, inFIG. 5, the guidewire has been removed laterally through the guidewire removing means along a portion of the length of thecatheter shaft12.
• In the simplest embodiment of the present invention theguidewire lumen20 may be provided simply with aproximal opening32, aside port34, and guidewire removing means40 extending distally of theproximal opening32 at least to theside port34, and perhaps beyond.
• However, more sophisticated versions of the present invention are also contemplated. In one such embodiment, adistal side opening54 may be provided through theoutside wall30 of theguidewire lumen20 to provide access into theguidewire lumen20 at a point distal of thesideport34. Thedistal side opening54 may be open in normal use; however, thedistal side opening54 is preferably covered with aremovable patch56, as best seen inFIGS. 3 and 5. Theremovable patch56 is preferably made of foil, Mylar, aluminized or metalized Mylar, or other suitable material, and may be held in place with an adhesive. Theremovable patch56 may be removed from thecatheter shaft12 to open up thedistal side opening54 to permit extension of theguidewire50 through thedistal side opening54 or to permit use of thedistal side opening54 as a perfusion opening. In one embodiment of the invention, theguidewire removing means40 extends distally to the distal side of thedistal side opening54.
• The portion of theguidewire lumen20 located proximally of theproximal opening32 is preferably closed, and may be filled with afiller60 such as a polymer material formed in place or a stylet inserted in a waterproof manner into theguidewire lumen20, as illustrated inFIGS. 3 and 5.
• In an alternative embodiment the invention, the catheter ofFIG. 1 is modified at its proximal end as illustrated inFIG. 6. Specifically, this particular catheter has a conventional “Y”connector62 at theproximal end14 of thecatheter shaft12 has theballoon inflation connector26 and aguidewire connector64 at the two “branches” of the “Y”. Theguidewire lumen20 extends from theproximal end14 of thecatheter shaft10 through theguidewire connector64 and the “Y”connector62 and extends distally the length of thecatheter shaft12.
• Theproximal opening32 is located distally of the “Y”connector62. Thecatheter10 is provided with a slidingcover66 that is axially movable to cover or uncover theproximal opening32. The slidingcover66 is preferably an annular sleeve circling thecatheter shaft12 and axially movable with respect thereto. The slidingcover66 preferably has a soft sealing material70 (such as a pliable closed cell polymer foam, a silicone elastomer, or other suitable material) on its inside surface to provide a seal against thecatheter shaft12. Ordinarily, the slidingcover66 is over theproximal opening32, closing and sealing theproximal opening32.
• In an alternative embodiment, the slidingcover66 may be replaced by a removable covering (not illustrated) similar to theremovable patch56 to close theproximal opening32 until it is used.
• In ordinary use, theguidewire50 extends distally through theguidewire connector64, the remainder of the “Y”connector62, inside theguidewire lumen20, past theproximal opening32, and out of thedistal end16 of thecatheter10. When required (as will be explained in more detail hereafter), the slidingcover66 or other seal covering theproximal opening32 is removed, thecatheter10 is maintained in place in the patient while theguidewire50 is removed proximally out of theguidewire connector64, and theguidewire50 is then inserted through theproximal opening32 until it is in the desired position. Then theguidewire50 is removed out through theoutside wall30 of theguidewire lumen20 as explained in more detail elsewhere. Removal of theguidewire50 through the outside wall of thecatheter shaft12 permits conversion of the catheter from an over-the-wire catheter to a rapid-exchange catheter that can be removed from the patient without extension of theguidewire50.
• In the embodiment illustrated inFIG. 6, because aconventional guidewire connector64 is ordinarily used, backbleeding during use is eliminated by tightening the Tuehy-Borst adapter (not shown) except when manipulating theguidewire50. This is in contrast to the embodiment illustrated inFIG. 1, where some backbleeding might be expected.
• In yet another embodiment of the invention, the guidewire removal and reinsertion explained in connection withFIG. 6 is eliminated by providing a removable “Y”connector80, illustrated inFIGS. 7-13.
• The particular embodiment of removable “Y” connector illustrated inFIG. 7 provides an axially separable “Y”connector80. The “Y”connector80 is preferably molded of a relatively hard thermoplastic material, and is adapted to fit concentrically around the catheter shaft. The removable “Y”connector80 is formed of 2 (or more) pieces which are joined together along lines extending in the axial or longitudinal direction of thecatheter shaft12. In the illustrated embodiment, the removable “Y” connector has anaxial portion82 through which the balloon lumen22 (and preferably the catheter shaft12) extends. The removable “Y”connector80 further has aguidewire connector64 extending proximally and at an angle outwardly from theaxial portion82 of the removable “Y”connector80.
• Theguidewire connector64 of the removable “Y”connector80 is cylindrical in shape and has a guidewire bore84 extending therethrough. The guidewire bore84 connects through theproximal opening32 into theguidewire lumen20, as best illustrated inFIG. 13.
• The removable “Y”connector80 is preferably formed of afirst half86 andsecond half90. Thefirst half86 and thesecond half90 each has a semicylindrical recess92,94 extending axially along the length of eachhalf86,90 of the removable “Y”connector80. The semi cylindrical recesses92,94 are best illustrated inFIG. 11. When the first andsecond halves86,90 are joined together, the semi cylindrical recesses92,94 together form a cylindrical recess through which thecatheter shaft12 extends.
• When the first andsecond halves86,90 are joined together on thecatheter shaft12, they are joined at afirst edge96 and asecond edge100 on opposite sides of thecatheter shaft12. The first andsecond edges96,100 of eachhalf86,90 extend axially parallel to the axis of thecatheter shaft12.
• In a preferred embodiment of the invention, thefirst edges96 of the first andsecond halves86,90 are joined by ahinge102. Preferably, thehinge102 is a “live” hinge; that is, a hinge formed of a thin portion of the polymer material of which the removable “Y”connector80 is formed. In a preferred embodiment, thehinge102 extends axially the entire length of thefirst edge96.
• The second edges100 of the first andsecond halves86,90 are separably joined together by any appropriate connecting mechanism. The illustrated mechanism is but one possibility. In the illustrated mechanism, thesecond edge100 of the first andsecond halves86,90, comprises on each half aradially extending tab104 running the length of thesecond edge100. At the outside radial edge of thetabs104 is aflange106 formed so that, when the first andsecond halves86,90 are mated together at theirsecond edges100, theflanges106 extend in opposite directions on the first andsecond halves86,90, forming a “T” shape in radial cross section as shown inFIG. 9.
• Anedge connector110 is provided to hold thesecond edges100 of the first andsecond halves86,90 together. Theedge connector110 preferably extends the entire length of thesecond edges100 and is formed with a “T” channel inside to lock together thetabs104 andflanges106 of thesecond edges100 of the first andsecond halves86,90. Thus, the “T” of the mated second edges of the firstsecond edges100 of the first andsecond halves86,90 is adapted to slide inside the “T” channel of theedge connector110. Once theconnector110 is placed on the “T” of the second edges, it may be locked in place using any appropriate mechanism. In one embodiment, afirst end112 of the connector is permanently closed to prevent movement of theedge connector110 in one direction. Thesecond end114 of theedge connector110 may have abreakaway end116, as illustrated inFIGS. 7 and 8. Thebreakaway end116 is glued or otherwise connected to the remainder of theconnector110 in such a manner that it may be readily severed from theedge connector110. This may be done by a rocking motion applied to thebreakaway end116 as illustrated in by thearrows120 inFIG. 7. Once thebreakaway end116 is removed as illustrated inFIG. 8, theconnector110 may be moved axially in the direction indicated byarrow122 until theedge connector110 is removed from the remainder of the removable “Y”connector80.
• Another method for locking theedge connector110 onto the removable “Y”connector80 is by use of alocking pin124 as illustrated inFIG. 10. The locking pin may extend through theedge connector110 and thesecond edges100 of the first andsecond halves86,90, to lock theedge connector100 in place. When thepin124 is removed, theedge connector110 may also be removed.
• Although thepin124 illustrated inFIG. 10 is circular, any other suitable pin or locking device may similarly be used.
• After the removal of theedge connector110, the first andsecond halves86,90 may be removed from thecatheter shaft12 as illustrated inFIG. 11 by pivoting thesecond edges100 away from each other. The removable “Y”connector80 may then be slid proximally off the proximal end of theguidewire50.
• In a preferred embodiment of the invention, aseal126 is provided around thecatheter shaft12 as illustrated inFIG. 12. Theseal126 prevents leakage between the removable “Y”connector80 and thecatheter shaft12, and is preferably formed of annular polymer material such as elastomeric material or closed cell foam. Theseal126 is preferably provided with anindex feature130 for preventing rotational or longitudinal movement of the in-place “Y”connector80 with respect to thecatheter shaft12. In the illustrated embodiment, theindex feature130 is an outwardly extending tab; however, theindex feature130 could alternatively be a groove, a recess, a flange, or the like. The outwardly-extendingindex feature130 illustrated inFIGS. 12 and 11 can cooperate with acomplimentary index receptacle132 on theaxial portion82 of the removable “Y”connector80.
• The use of the removable “Y” connector is further illustrated inFIGS. 14 and 15. Thecatheter10 without the “Y”connector80 in place is illustrated inFIG. 14. Aguidewire50 is inserted, into theproximal opening32 through theguidewire connector64, as seen inFIG. 15. Theguidewire50 extends the length of thecatheter shaft12 and out of thedistal end16 of thecatheter10.
• When the removable “Y”connector80 is removed from thecatheter shaft12, thecatheter10 is properly illustrated inFIG. 3, and theguidewire50 can be removed laterally through theoutside wall30 of theguidewire lumen20 as illustrated inFIGS. 3 and 5, and as previously explained.
• Although the removable “Y”connector80 has been discussed in the context of a particular preferred embodiment, it will be understood that equivalent removable “Y” connectors can be provided in which only a portion (such as a strip) of the “Y” connector is removed from thecatheter shaft12; or where there are more than two separable pieces of the “Y” connector; or where alternative latches or locking mechanisms are utilized to hold the removable “Y” connector together until removal is desired. Further, other mechanical features having equivalent function can be substituted for others of the various described elements.
• Methods of Using the Convertible Mode Catheter
• The catheter of the present invention may be used as a rapid-exchange catheter with theguidewire50 extending through theside port34 and out of thedistal end16 of theguidewire lumen20. Alternatively, it may be used as a conventional over-the-wire catheter with theguidewire50 extending substantially the entire length of thecatheter shaft12 from the proximal end (either through a conventional “Y”connector62 or a removable “Y”connector80 or through the proximal opening32) distally through the entire length of the catheter shaft and out of the distal end thereof.
• A revolutionary aspect of the catheter of the present invention is that it may readily and rapidly be converted from one mode of use to the other. Thus, it can be used first as a rapid-exchange catheter, with the guidewire extending in theguidewire lumen20 only from theside port34 to the distal end of the catheter. It can be converted from this rapid-exchange mode of use to conventional over-the-wire use simply by removing the guidewire and, while maintaining thecatheter10 in place in the patient, inserting anew guidewire50 into the proximal end of the guidewire lumen20 (through a “Y” connector or through the proximal opening32) and extending theguidewire50 out of the distal end of thecatheter10.
• When the catheter ofFIG. 4 is being used as a conventional over-the-wire catheter, it can be converted into a rapid-exchange catheter by removing the removable “Y” connector80 (if used), and, with the guidewire extending proximally out of theproximal opening32, maintaining theguidewire50 in position in the patient while moving the guidewire laterally out of theoutside wall30 of theguidewire lumen20 through theguidewire removing means40 and simultaneously withdrawing thecatheter10 proximally until thedistal end16 of thecatheter10 is outside of the patient. During this portion of the procedure, theguidewire50 is held by grasping it at the proximal end. Then the operator may hold theguidewire50 by grasping the portion of theguidewire50 exposed at thedistal end16 of thecatheter10, remove thecatheter10 off of the proximal end of theguidewire50, and insert anew catheter10 over theguidewire50 while maintaining the position of theguidewire50 in the patient. The insertion of thenew catheter10 may be accomplished in rapid-exchange mode by retrograde insertion of the proximal end of theguidewire50 through the distal end of the catheter and out of theside port34. The proximal end of the guidewire is then held while thecatheter10 is advanced back into position in the patient. The catheter can then be used as a rapid-exchange catheter. Alternatively, if desired, theguidewire50 may be removed with the catheter maintained in position, and in a matter of seconds the guidewire may be reinserted through theproximal opening32 or through theproximal end14 of thecatheter shaft12 to convert the mode of use to conventional over-the-wire use.
• Thus, it will be appreciated that the catheter of the present invention can easily be used in either a rapid-exchange mode or an over-the-wire mode; that conversion between modes of use may be readily accomplished; that guidewire exchange may be accomplished in either mode of use, and that catheter exchange when in either mode of use can be accomplished without use of an extension guidewire; and that all of the forgoing conversions and modes of use can be accomplished while maintaining the positioning of either the guidewire or the catheter in the patient.
• Thus, one method of the present invention comprises inserting the catheter ofFIG. 1 into the patient with theguidewire50 going through theproximal opening32 and extending from that point distally through the entire remaining length of thecatheter shaft12 and out of thedistal end16. Theguidewire50 can then be exchanged by removing it and reinserting it through theproximal opening32. The catheter can be exchanged by holding the guidewire as explained above while peeling away the catheter laterally while withdrawing it so that the guidewire is pulled through the guidewire removing means40 until the distal end of the-catheter is outside the patient. The guidewire is then held distally of the catheter and a new catheter is inserted, this time in rapid-exchange mode. Once that catheter is in place, the guidewire can be rapidly exchanged (if desired) to convert the catheter back into the over-the-wire mode of use as explained above.
• In another method of use, the catheter ofFIG. 6 can be used. This catheter can be used with the guidewire in the side port or the proximal opening, as explained above, with the same catheter and guidewire exchanges possible. Moreover, it can be used with the guidewire extending through the entire length of theguidewire lumen20 through theguidewire connector64. Exchange of the guidewire from theguidewire connector64 to theproximal opening32 and vice versa is also contemplated.
• The identical modes of use explained in connection with theFIG. 1 catheter can be used with the removable “Y” connector catheter ofFIGS. 7-15, except the guidewire passes simultaneously through theproximal opening32 and theguidewire adapter64 of the removable “Y”connector80. Further, in these modes of use, the conversion from over-the-wire use to rapid-exchange use will require removal of the “Y”connector80 prior to and in addition to use of theguidewire removing means40.
• Although the present invention has been described in the context of certain preferred embodiments, it is intended that the scope of the present patent be measured with reference with the appended claims and reasonable equivalence thereof.
• While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims (1)

1. A catheter comprising:

a catheter shaft having a proximal end and a distal end;

an expandable member mounted on the shaft near the distal end;

a guidewire lumen extending through the shaft and adapted for receiving a guidewire, the guidewire lumen having an outside wall, the guidewire lumen extending from a location at or near the proximal end of the shaft to a location proximate the distal end of the shaft; and

guidewire removing means in the outside wall of the guidewire lumen for permitting a guidewire in the guidewire lumen to be moved laterally from the guidewire lumen though the outside wall of the guidewire lumen, the means extending from a first location at or near the proximal end of the shaft to a second location proximate the distal end of the shaft.

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