US20050261667A1 - Infusion device and method - Google Patents

Abstract

Devices and methods for performing improved percutaneous myocardial revascularization (PMR) procedures. One device includes a preassembled PMR drug delivery catheter and a drug neutralizing vial. The vial assembly allows prepping the PMR catheter by flushing drug through distal needle, and into a vial cavity where the drug is neutralized by a neutralizing agent. One set of devices includes needles having protrusions secured to the distal regions of drug delivery tubes. One needle has outward protruding barbs engaging the inner tube wall while another needle has outward threads which can screw into the tube inner wall. Radiopaque marker bands are also included in the present invention which are asymmetrically distributed on the catheter shaft, allowing a treating physician to determine under fluoroscopy whether the catheter distal region is pointed away or toward the treating physician, as well as determining whether the catheter distal region is rotated toward or away from the treating physician. PMR devices include catheters having dual injection needles, for both injecting a drug into the heart wall and a radiopaque contrast media to mark the already treated sites. One PMR injection device has multiple stops for allowing controlled, variable needle depth penetration with a single distal needle tip.

Description

RELATED CASES
• The present application is a continuation of U.S. application Ser. No. 10/621,378, which was filed on Jul. 18, 2003, was entitled Infusion Devices and Method and is now U.S. Pat. No. ______. The '378 application is itself a continuation of U.S. Pat. No. 6,616,626, which was filed on Dec. 21, 2000 and shares the same name.
FIELD OF THE INVENTION
• The present invention is related generally to medical devices. More specifically, the present invention is related to devices and methods associated with delivery of genes or therapeutic substances.
BACKGROUND OF THE INVENTION
• A number of techniques are available for treating heart disease and diseases of other organs percutaneously. Examples of such techniques include delivery of genes and therapeutic substances, including the delivery of genes and therapeutic substances for percutaneous myocardial revascularization (PMR). This procedure is performed to increase blood perfusion through the myocardium of a patient. For example, in some patients, the number of lesions in coronary vessels is so great or the location so remote in the patient vasculature that restoring blood flow to the heart muscle is difficult. Percutaneous myocardial revascularization (PMR) has been developed as an alternative to techniques which are directed at bypassing or removing lesions. PMR is performed by boring holes directly into the myocardium of the heart. Positive results have been demonstrated in some human patients receiving PMR treatments. These results are believed to be caused in part by blood flowing from within a heart chamber through patent holes formed by PMR to the myocardial tissue. Suitable PMR holes have been proposed to be burned by laser, cut by mechanical means, and burned by radio frequency devices. Increased blood flow to the myocardium is also believed to be caused in part by the healing response to wound formation, specifically, the formation of new blood vessels in response to the newly created wound.
• Several aspects of PMR procedures could be improved upon. One area for improvement is in the preparation of PMR injection catheters for use by the treating physician. In particular, at present, the PMR device maybe flushed with a drug to prime the distal needle by flushing the drug through the needle and into a container. This preparation can be awkward and may leave a container of biologically active material which may require further processing. Another aspect which may be farther optimized lies in the attachment of the needle to the distal region of the PMR catheter tube. In particular, forces may act upon the needle during both the advancement and retraction of the needle within the heart wall, urging the needle undesirably both into and out of the tube. Improved methods of securing the needle to the tube would be desirable.
• During a PMR treatment, a physician may be attempting to treat a three-dimensional space using a catheter having a distal bend. In particular, the physician may be attempting to treat the heart chamber side, anterior, and posterior wall regions. This may presently be difficult to visualize under fluoroscopy as current marking systems for shafts may make interpretation of the catheter distal region orientation somewhat ambiguous. The heart chamber wall thickness can vary depending on the chamber and wall region being treated. In particular, the left ventricle wall is thinner in the posterior region relative to the anterior region. Improved devices for variable depth, yet controlled penetration of the heart walls, would be advantageous. As multiple sites of the heart chamber wall are penetrated, a system for tracking the treated versus untreated regions would also be desirable.
SUMMARY OF THE INVENTION
• The present invention includes improved devices and methods for performing PMR procedures. One device allows for improved preparation of PMR catheters used to inject a drug or therapeutic substance into the heart wall. One such device includes a PMR device distal region or hood disposed within the neck of a vial for receiving the drug. The vial can be used to receive the drug while the drug is being flushed through the PMR device and needle to prepare the PMR device for use. One vial has a neck and shoulder region for receiving and retaining the distal region of a PMR injection device. A no-leak gasket defines one wall of an inner cavity within one such vial.
• The vial is preferably formed of a transparent or translucent material for observing the injection of the drug into the vial. In one embodiment, the vial cavity includes a drug-neutralizing agent. The agent allows the drug to be neutralized after receiving the drug. A neutralizing agent can provide improved safety, should the integrity of the vial be breached. The drug-neutralizing vial allows a biologically active drug to be flushed through the catheter with the vial being disposed of in a normal waste stream such as a wastebasket, rather than requiring special handling.
• One set of devices provides improved needle attachment to drug delivery tubes. One improved drug delivery tube has an outer tube defining a lumen therein. A needle may be disposed within the distal end of the tube. The needle can have a distal, sharp tube region for insertion into the heart wall, as a well as a wider, more proximal region having outward protrusions for engaging or biting into the drug delivery tube inner wall. One device has a wide flange for abutting the drug delivery tube distal end, thereby limiting the proximal travel of the needle into the drug delivery tube lumen. One drug delivery tube also has a bonding hole which can be used to inject an adhesive to further secure the needle within the drug delivery tube distal region. The improved securing of the needle to the drug delivery tube can act to prevent the needle from being distally pulled from the tube.
• During insertion of the needle into the heart wall, forces can act to urge the needle into the tube. Upon retraction of the needle from the heart wall, forces may act to pull the needle distally from the tube. Both the outward protrusions, the flange, and the added adhesive can act to better secure the needle to the drug delivery tube. One embodiment includes outward barbs biting into the drug delivery tube, while another embodiment uses a series of helically disposed screw threads to engage the tube wall. A preferred embodiment uses outward protruding elements which engage the inner wall, while another embodiment uses inwardly protruding elements engaging the outer wall of the tube distal region.
• Another aspect of the invention provides improved visualization of the catheter shaft orientation under fluoroscopy. One embodiment utilizes asymmetrically disposed radiopaque markers on the shaft distal region to enable the treating physician to determine whether the catheter distal region is pointed at right angles to the treating physician or is pointed toward or away from the treating physician. One embodiment has the radiopaque marker being asymmetrically distributed with respect to a plane bisecting a longitudinal axis of the catheter tube distal region. Another embodiment further includes the radiopaque marker being asymmetrically distributed with respect to length over the catheter distal region. One marker includes an annular ring portion and a straight leg portion lying along the length of one side of the tube. Yet another embodiment includes an annular shell or ring portion and an annular arc leg portion extending along a length from the annular shell or ring portion. The radiopaque markers may be disposed on either the proximal or the distal side of any bend in the catheter shaft. A preferred use of the radiopaque marker band is on a guide catheter used to guide a PMR therapeutic tip to the heart wall.
• In yet another aspect of the invention, radiopaque marker segments are asymmetrically distributed such that the rotation of the tube relative to the treating physician may be determined under fluoroscopy. One embodiment uses opposing annular shells on opposing sides of a tube where the annular shells are shifted longitudinally relative to each other. The asymmetrically disposed shells are thus asymmetric both with respect to a plane bisecting a longitudinal central access and with respect to a plane transversely bisecting a catheter shaft.
• In still another aspect of the invention, marker bands are provided a distance apart which approximates the desired inter-treatment site spacing along the heart wall. A method can be performed using this aspect of the invention, whereby a therapeutic substance is delivered at treatment sites which are observed under fluoroscopy to be spaced apart approximately the distance between marker bands. Any distortion or magnification of the distances between marker bands will approximately be matched by distortions between treatment sites.
• The present invention also includes a PMR device for allowing precise, variable depth needle penetration of the heart wall. One device includes at least one inner stop affixed to a rotatable inner needle. The device also can have one or more stops disposed inwardly from an outer tube, the outer tube having the inner needle rotatably disposed within. The inner needle can be longitudinally advanced until the inner stop abuts an outer stop, thereby inhibiting further distal movement of the inner needle. If greater penetration is desired, the inner shaft can be rotated, thereby swinging the inner stop clear of the first encountered outer stop, allowing the inner stop to proceed further distally until a subsequent outer stop is encountered. This aspect of the invention allows a single device to be used, yet provides multiple, preset, precise penetration depths. This may be of particular use where the thickness of the heart wall varies over different regions of the heart chamber wall.
• Yet another aspect of the invention provides for injection of drug and contrast media into the heart wall. Injection of contrast media near the injection site of a drug allows the treating physician to visualize under fluoroscopy which areas of the heart wall have been treated and which have not yet been treated. One device provides a contrast media injection needle disposed side-by-side with a drug delivery needle. One embodiment allows the two side-by-side needles to be retracted and advanced together. The needles can be distally straight, arcuate, or one arcuate and one straight. Another embodiment provides a drug and contrast media injection device having a pair of needles, one being coaxially disposed within the other. The innermost needle can be used to inject drug deep into the heart tissue, while the more outer, coaxially disposed needle may be used to inject contrast media to the heart wall, thereby marking the site of treatment. One embodiment utilizes a sharp, cutting end to inject contrast media. Another embodiment uses a less sharp, less cutting end, for injecting a contrast media into the heart wall tissue using pressure, rather than cutting.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a fragmentary, side, cutaway view of a myocardial revascularization preparation system including a drug neutralizing vial and a myocardial revascularization drug delivery catheter in the process of being prepared for use by flushing a drug through the injection needle into the drug-neutralizing vial;
• FIG. 2 is a fragmentary, longitudinal, cross-sectional view of a drug delivery catheter distal portion having a needle disposed within a tube, the needle having barbs for engaging the tube inner wall to improve needle retention;
• FIG. 3 is a fragmentary, longitudinal, cross-sectional view of a drug delivery catheter distal portion having a needle disposed within a tube, the needle having threads for engaging the tube inner wall to improve needle retention;
• FIGS. 4A-4C are perspective views of a prior art catheter shaft having an annular radiopaque band;
• FIGS. 5A-5C are perspective views of a catheter shaft having an asymmetric radiopaque marker;
• FIGS. 5D-5E are transverse, cross-sectional views taken through the catheter ofFIGS. 5A-5C;
• FIGS. 6A-6C are perspective views of a catheter having an asymmetric radiopaque marker;
• FIGS. 6D-6E are transverse, cross-sectional views taken through the catheter ofFIGS. 6A-6C;
• FIG. 7 is a perspective view of a catheter shaft having an asymmetric, radiopaque marker disposed proximal of a bend;
• FIGS. 8A-8H are plan views of a catheter shaft having an asymmetric radiopaque marker in varying degrees of rotation;
• FIGS. 9A and 9B are perspective views of a guide catheter shaft including radiopaque marker bands having an inter-band distance corresponding to a desired myocardial revascularization treatment site spacing;
• FIG. 10 is a fragmentary, longitudinal cross-sectional view of a PMR catheter having multiple stops for controlling needle penetration;
• FIGS. 11A-11C are fragmentary, longitudinal cross-sectional views of a PMR catheter having side-by-side needles for injection of a drug and a radiopaque fluid; and
• FIGS. 12A-12B are fragmentary, longitudinal cross-sectional views of PMR devices having coaxially disposed drug and dye delivery lumens.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• FIG. 1 illustrates a myocardial revascularization drugdelivery preparation assembly30 including adrug receiving vial32 and adrug delivery catheter42 inserted intovial32.Drug delivery catheter42 includes atube44 having alumen46 therethrough.Catheter42 includes adistal portion54 having an injection device orneedle50 in fluid communication withlumen46.Catheter42 further includes adistal hood48, illustrated in an expanded state.Drug injection needle50 is illustrated penetrating through a self-sealing, no-leak gasket40.Gasket40 can be disposed withinvial32 in anannular seat52, as shown.
• Drug receiving vial32 includes awall38, which is preferably formed of a transparent or translucent material, allowing both an expelled drug and catheter needle to be viewed through the vial wall.Vial32 includes acavity34 having a drug-neutralizingagent36 disposed withincavity34.Vial32 includes aneck region58 for receiving catheterdistal portion54. In one embodiment,vial32 further includes a shoulder orcontour region56 for engaging catheterdistal hood48. In some embodiments,vial shoulder56 andcatheter hood48 are cooperatively sized such thatshoulder56 engageshood48 even whenhood48 is in a non-expanded state.Hood48 is preferably sufficiently compliant so as to allow retraction ofhood48 throughvial neck region58 after preparing the catheter.Vial shoulder56 can also flex to containhood48.
• In use, drug deliverycatheter preparing system30 can be provided substantially as illustrated inFIG. 1.Catheter42 can be provided either separate from, or already engaged within,vial neck region58. Whencatheter42 is to be prepared,catheter42distal portion54 can be inserted intovial neck region58, if not already so disposed.Catheter42 can be further advanced, forcingneedle50 throughgasket40, and intocavity34. Withneedle50 inserted throughgasket40, the drug to be delivered can be flushed throughneedle50 intocavity34, preferably mixing with a neutralizing agent. In this way, the drug to be delivered can be loaded intocatheter42, preparing the catheter for use. The excess drug can be contained withincavity34, which may be desirable where the drug is potentially harmful or must be isolated for other reasons.Catheter42 can be retracted fromvial32 when needed.Gasket40 is preferably formed of a self-sealing material, such that a seal is re-formed afterneedle50 is withdrawn. In embodiments having a drug-neutralizing agent, the contents of the vial will be harmless, even if the vial integrity is compromised. After preparing,vial32 can be disposed of in a proper manner. In some embodiments,vial32, containing either a harmless or a neutralized drug, may be disposed of in a wastebasket, with no special handling required.
• Catheter42 can be used to inject various drugs or other therapeutic substances into the myocardium. Examples of therapeutic substances include small molecular drugs, proteins, genes and cells which could promote angiogenesis, protect tissues (i.e., cardiac protection), or promote tissue regeneration. Vascular Endothelial Growth Factor (VEGF) and Fibroblast Growth Factors (FGFs) are believed suitable for use with the present invention. Carriers for the therapeutic agents of the present invention can include polymers, angiopoietins, biodegradable and biostable hydrogels, and dissoluble polymers. Adhesives suitable for binding the present invention include fibrin glues and cyanoacrylates which may also be included with the therapeutic substance to improve the desired response. Drug injection catheters referred to in the remainder of the present patent application, and drugs similarly referenced, may include the injection and use of the aforementioned therapeutic substances.
• Catheter42, as well as subsequently referenced drug injection catheters or myocardial revascularization catheters, can include catheters such as those described in co-pending U.S. patent application Ser. No. 09/271,045, filed Mar. 17, 1999, entitled TRANSMYOCARDIAL REVASCULARIZATION CATHETER AND ASSEMBLY; and U.S. patent application Ser. No. 09/184,220, filed Nov. 2, 1998, entitled PERCUTANEOUS MYOCARDIAL REVASCULARIZATION GROWTH FACTOR MEDIUMS AND METHOD, herein incorporated by reference. In particular, guide catheters described according to the present invention may be used to guide these previously referenced devices, and others, to target sites in the myocardium.
• FIG. 2 illustrates the distal portion of adrug delivery catheter60 which, in a preferred use, can be used for a procedure such as myocardial revascularization.Drug delivery catheter60 includes a tube62 having a wall64 defining adrug delivery lumen66 within.Catheter60 has adistal region68, terminating in adistal end76. Disposed within catheter tube62 is a drug delivery needle78, including generally a wider, proximal portion80, and a narrower,distal portion82.Distal portion82 includes anelongate tube83 terminating in asharp end84. Needle wide proximal portion80, in the embodiment illustrated, includes a plurality ofwider protrusions88 spaced apart from each other by a plurality of narrower regions90.Protrusions88, in a preferred embodiment, include sharp tips or barbs86 for engaging and gripping tube wall64.
• As can be seen inFIG. 2, outward protrusions or barbs86 may form a plurality ofdeformations69 where the barbs dig into tube wall64. In a preferred embodiment, barbs86 have at least a slight inclination toward the distal direction, such that retraction of needle78 from tube62 is more difficult than insertion of needle78 into tube62. In a preferred embodiment,drug delivery catheter60 includes adistal flange72 which can serve to limit travel of needle78 intodrug lumen66. In the embodiment illustrated,flange72 abuts tubedistal end76 and has ahole74 therethrough for receiving needledistal tube portion83. In one embodiment, tube62 includes abonding hole70 through tube wall64 for receiving adhesive. Adhesive can be injected throughhole70 for improving the adherence of needle wide portion80 to tubedistal region68.
• In one use,drug delivery catheter60 can be advanced through the vasculature and into a heart chamber wall. After injection of a drug throughdrug lumen66,drug delivery catheter60 can be retracted, thereby retracting needledistal end84. In a situation where the heart wall grips needledistal tube portion83, barbs or protrusions86 can serve to resist the distally directed force attempting to retain needle78.
• Anotherdrug delivery catheter100 is illustrated inFIG. 3, having aneedle114 disposed within atube102.Tube102 includes atube wall104 having aninner surface108 and anouter surface107.Tube102 includes adistal region110, adistal end112, and alumen106 disposed therethrough.Needle114 includes adistal tip region116 ending distally in a sharpdistal end118.Needle114 also includes aproximal needle portion118 including a plurality ofthreads120 which are spaced apart and havenarrower regions121 disposed betweenthreads120.Needle114 includes aneedle lumen124 extending throughneedle114 and having aproximal throat region126.Throat126 can improve the flow characteristics of fluid through the needle.Needle threads120 may be seen to engage or bite intotube wall104. In the embodiment illustrated,threads120 are disposed on the outside ofneedle114, and engageinner surface108 oftube wall104. In another embodiment, not requiring illustration, the proximal portion of the needle extends overtube104. In this embodiment, threads are disposed inward within the needle lumen and engage tubeouter surface107, rather than the inner surface.Needle114 can be secured totube102 by advancingneedle114 intotube lumen106 and rotating114, thereby screwingneedle114 intotube lumen106.Threads120 thussecure needle114 totube102 and resist the distally directed forces attempting to urgeneedle114 out oftube102.
• FIGS. 4A through 4C illustrate a priorart catheter shaft130 having abend134 and extending to adistal end132.Catheter shaft130 has anannular band136 which includes a radiopaque material.FIG. 4A is a side view,viewing catheter shaft130 from an angle of about ninety degrees (90.degree.) away from a straight-on end view looking directly along the central longitudinal axis.FIG. 4B illustratescatheter130 viewed from an angle of less than ninety degrees (90.degree.) off the center longitudinal axis.FIG. 4B illustratescatheter shaft130 wheredistal end132 is pointed more toward the viewer than away.FIG. 4C illustratescatheter shaft130 being pointed more away from than toward the viewer.FIGS. 4B and 4C illustrate that annularradiopaque band136 looks somewhat elliptical, and looks about the same, whether viewed from the front or the back.Annular band136 thus looks the same when catheter shaftdistal end132 is pointed toward or away from the viewer. Annularradiopaque band136 gives no indication under fluoroscopy of the direction the catheter shaft distal end is pointed. This is a less than optimal attribute of annularradiopaque band136, when used in an application such as myocardial revascularization, where the catheter shaft may be rotated and translated in all directions.
• FIGS. 5A through 5E illustrate acatheter shaft140 having an asymmetric radiopaque marker.Catheter shaft140 includes abend141 disposed proximal of a distal end142.Catheter140 includes an asymmetricradiopaque marker144 including a first, annular orring portion146 extending radially about the catheter and disposed transversely to the catheter longitudinal axis, and a second,straight portion148, extending along one side ofshaft140 toward distal end142.FIG. 5A illustrates a side view ofcatheter shaft140. The view ofFIG. 5A is taken from about ninety degrees (90.degree.) away from a straight-on end view, a view which would look directly along the central longitudinal axis.FIG. 5B illustrates a view ofcatheter shaft140 with shaft distal end142 pointed more toward the viewer than away.FIG. 5C illustratescatheter shaft140 having distal end142 pointed more away from the viewer than toward the viewer. As can be seen from inspection ofFIGS. 5B and 5C,marker144 appears differently when the catheter distal end is pointed away from the viewer compared to pointing toward the viewer. Theasymmetric marker band146 thus provides an indication under fluoroscopy of whether the catheter is pointed away from, or toward the viewer.
• FIG. 5D illustrates the asymmetric nature ofradiopaque marker144. FIG. SD, taken throughannular ring portion146, shows a more proximal slice throughcatheter shaft140.FIG. 5E, taken through a more distal portion ofcatheter140, illustratesmarker144 havingstraight leg portion148 only on one side. It may be seen fromFIGS. 5A through 5E that a plane bisecting the central longitudinal axis ofcatheter shaft140, will have differing, asymmetrical portions of radiopaque marker on either side of the bisecting plane. In particular, the markers on either side of the bisecting plane are not mirror images of each other. It may also be seen thatmarker144, when compared proximal end to distal end, is asymmetric along its length. In particular,radiopaque marker144 does not have a distal portion which is a mirror image of its more proximal portion.
• FIG. 6A illustrates acatheter160 having aradiopaque marker164 which is asymmetric and includes a first, annulararc shell portion166, and a second,annular ring portion168. InFIG. 6A, it may be seen that a plane bisecting the central longitudinal axis ofcatheter160 would have an asymmetry with respect to the marker about the bisecting plane. In particular, the right and left halves ofcatheter160 are not mirror images of each other. InFIG. 6A, catheterdistal end160 is pointed directly at the viewer. InFIG. 6B,catheter160 is directed such that catheterdistal end162 is pointed ninety degrees (90.degree.) away from the viewer, directly to the side. InFIG. 6C,catheter160 is pointed one hundred eighty degrees (180.degree.) away from the viewer, toward the back. Comparison ofFIGS. 6A through 6C illustrates thatmarker164 appears differently depending whether catheterdistal end162 is pointed toward the viewer, to the side of the viewer, or away from the viewer.FIG. 6D shows a transverse cross-section taken through radiopaqueannular shell166.Annular arc shell166 extends along the length of the catheter and substantially parallel to the central longitudinal axis, similar in some respects tostraight segment140 ofFIGS. 5A through 5E, but wider.FIG. 6E shows a transverse cross-section taken throughmarker164 throughannular ring168. The asymmetry about the bisecting plane may be seen inFIGS. 6D and 6E, as well.Radiopaque marker164 may also be seen to be asymmetric about a transverse bisecting plane. In particular, the top half ofmarker164 inFIG. 6A is not the mirror image of a bottom half ofmarker164 inFIG. 6A.
• In comparingFIGS. 5A through 5C and6A through6C, it may be seen that both embodiments, when viewed from an angle orthogonal to a plane containing the shaft on either side of the bend, have an asymmetric marker having two portions. The first portion lies substantially within a plane transverse to the center longitudinal axis. The second portion lies substantially within a plane that contains the center longitudinal axis. One embodiment has the marker disposed proximal of the bend, while the other embodiment has the marker disposed distal of the bend. One embodiment indicates shaft rotation proximal of the bend directly and infers the orientation of the segment distal of the bend. Another embodiment indicates shaft rotation distal of the bend directly and infers the orientation of the segment proximal of the bend. The other embodiment, not requiring illustration, has both the markers ofFIGS. 5A through 5C and6A through6C on the same shaft.
• FIG. 7 illustrates acatheter shaft200 having a radiopaque marker201 including afirst portion206 and asecond portion208.Catheter200 has abend202 and-adistal end204. In the embodiment illustrated,catheter200 has alumen210 extending therethrough. As can be seen from inspection ofFIG. 7, a plane bisecting the center longitudinal axis throughcatheter shaft200 would bisect radiopaque marker201 into twohalves206 and208, with the halves being asymmetric relative to the bisecting plane. In particular,first marker portion206 andsecond marker portion208 are not mirror images of each other with respect to a bisecting plane sending through the central axis. Radiopaque marker201 is also not symmetrical with respect to a transverse bisecting plane. The asymmetry causes marker201 to appear differently depending on the rotation of the tube with respect to a viewer. In particular, marker201 will appear differently under fluoroscopy depending on the degree to which the catheter is rotated about its central, longitudinal axis proximal ofbend202.
• FIG. 8A illustrates acatheter shaft220 somewhat similar tocatheter shaft200 ofFIG. 7.Catheter shaft220 has adistal end224, a first or leftmarker portion226, and a second orright marker portion228. Together, first andsecond marker portions226 and228 form anasymmetric marker230 which is asymmetric about a bisecting plane extending through the center longitudinal axis ofcatheter shaft220. InFIG. 8A,catheter shaft220 is rotated such that catheterdistal end224 is disposed at an angle of zero degrees (0.degree.) relative to the viewer. Catheter shaftdistal end224 is directed directly at the viewer.FIG. 8B illustratescatheter shaft220 rotated at a forty-five degree (45.degree.) angle relative to the viewer, yet still remaining in a somewhat forward disposition. Similarly,FIG. 8C illustratescatheter220 rotated at ninety degrees (90.degree.) relative to the viewer, andFIG. 8D has the catheter pointed at a one hundred thirty five degree (135.degree.) angle away from the viewer.FIG. 8E illustratescatheter shaft220 being pointed directly away from the viewer, followed byFIG. 8F, which illustrates the same catheter pointing away from the viewer, but at an angle of two hundred twenty five degrees (225.degree.).FIG. 8G illustratescatheter shaft220 being rotated sufficiently to point two hundred seventy degrees (270.degree.) relative to the line of view, toward the side. Finally,FIG. 8H illustratescatheter shaft220 being pointed three hundred fifteen degrees (315.degree.) away from its initial location, pointing mainly toward the viewer, but at a slight angle to the left.
• As can be seen from inspection ofFIGS. 8A through 8H,catheter marker230 appears differently under fluoroscopy depending on the rotation of the marker relative to the viewer. In particular, the marker is asymmetrically disposed on the catheter shaft such that rotation of the catheter about its longitudinal center axis appears different, relative to a fixed viewer orthogonal to the longitudinal axis of the catheter shaft. Marker201 thus enables a viewer using fluoroscopy to determine the angle of rotation of the catheter shaft about its longitudinal axis. This can prove useful in a myocardial revascularization procedure, where turning the catheter in varying degrees can be important, as the degree of rotation may correspond to the location of holes formed in the heart chamber wall.
• FIG. 9A illustrates acatheter shaft240 having abend242 and adistal end244.Catheter shaft240 further has a firstradiopaque marker band246 and a secondradiopaque marker band248 disposed at a known distance “D1” apart. In a preferred embodiment,marker bands246 and248 are disposed at a distance apart of between about 1-2 cm.FIG. 9B illustratescatheter240 being rotated toward and to the left of the viewer. Atreatment catheter250 may be seen to extend from catheter shaftdistal end244.Treatment catheter250 may be seen to have atherapeutic tip252. Afirst treatment site254 is represented by an “X” inFIG. 9B. As illustrated inFIG. 9B,therapeutic tip252 has been moved to a distance of about “D2” fromfirst treatment site254. In the embodiment illustrated,therapeutic tip252 is about to treat asecond site256, where the inter-site distance, D2, is substantially equal to the D1 distance. The marker bands may thus be used as a scale to accurately space the treatments sites in the heart chamber wall. The marker bands, being spaced apart about the same distance as the desired treatment spacing, will be subject to the same magnifications and/or distortions under fluoroscopy. This means that even if the distance between the markers appears distorted under fluoroscopy, the distance between target sites will likewise be distorted by about the same amount.
• FIG. 10 illustrates aPMR catheter280 including aninner needle282 rotatably disposed within anouter tube284.Inner needle282 includes ashaft286, and can terminate distally in asharp needle tip288.Outer tube284 includes atube wall290, and has a distal flange orhood292. Ahole293 is disposed withindistal flange292 for receivingneedle tip288. In the embodiment illustrated,inner needle282 has aninner stop294 secured toinner shaft286.Inner stop294 is secured toinner shaft286 such that rotating the inner shaft rotates the inner stop. In this embodiment,outer tube284 hasouter stops295,296, and297 secured at various longitudinal and angular locations alongtube wall290. As can be seen from inspection ofFIG. 10,inner stop294, if advanced further distally, will encounterouter stop295 which will limit the distal travel ofneedle tip288. It may also be seen that rotatinginner shaft286 by ninety degrees (90.degree.) will allowinner stop294 to clearouter stop294 and proceed distally further. In an embodiment whereinner stop294 has a hemispherical configuration, rotatinginner shaft286 by one hundred eighty degrees (180.degree.) would allowneedle tip288 to travel distally, yet be stopped byouter stop296, again requiring one hundred eighty degree (180.degree.) rotation to allow further distal travel of the needle tip. Thus, twisting the inner shaft can allow the depth of penetration to be controlled. In some embodiments, the inner and outer stops are formed of radiopaque material, allowing the degree of penetration to be observed under fluoroscopy. Having staggered stops, as illustrated inFIG. 10, allows the penetration depths to be accurately controlled from the proximal end of the catheter. This may be of particular importance in PMR procedures due to the varying thickness of the heart wall.
• FIG. 11A illustrates aPMR device400 extending from aproximal region402 to adistal region404 and having adistal flange410.PMR device400 includes anouter tube408 defining anouter lumen412 within and slidably containing aninner tube414 having afirst lumen416 and asecond lumen418 disposed within. In one embodiment, the two lumens are formed within a multi-lumen extrusion ofinner tube414. In another embodiment, the twolumens416 and418 are defined by separate tubes which are joined together along their length.First lumen416 may have a fluid injected through a firstmanifold port420 disposed inproximal region402 extending through afirst access tube417 which can definefirst lumen416 in the proximal region.First lumen416 extends distally to afirst injection needle426 which may be seen to have an arcuatedistal region427. Similarly,second lumen418 may be seen to extend from a secondmanifold port422, through a secondproximal tube419, extending distally to a second fluid injection needle428. In the embodiment illustrated,first injection needle426 is curved, while second injection needle428 is substantially straight in the distal region.
• In one embodiment,first lumen416 is used to inject radiopaque fluid, whilesecond lumen418 is used to inject a drug as part of the PMR procedure. In another embodiment,first lumen416 is used to inject a drug, whilesecond lumen418 is used to inject a radiopaque material. In this latter embodiment, the straight needle428 can be used to inject radiopaque material at the center of a circular pattern formed by the repeated injection of a drug throughfirst needle426. Injection of the radiopaque fluid allows the treating physician to visualize under fluoroscopy which areas of the heart wall have already been treated with the drug.
• FIG. 11B illustrates a distalPMR device region434, similar todistal region404 ofFIG. 11A, and having similar proximal regions, but having a different configuration for the two distal needles. In the embodiment illustrated, the PMR device distal region includesouter tube408,inner tube414, and first andsecond lumens416 and418, as inFIG. 11A.First needle426 hasarcuate region427. In this embodiment, asecond needle430 is illustrated, also having arcuatedistal segment432. In this embodiment, both first and second needles have arcuate distal regions.FIG. 11C illustratesdistal region434 ofFIG. 1B, shown in a retracted configuration.First needle426 andsecond needle430 may be seen to be retracted withinouter tube408.
• FIGS. 12A and 12B illustrate other embodiments of PMR device distal regions, with the proximal regions not requiring illustration and having somewhat similar designs to those ofFIG. 11A.FIG. 12A illustrates aPMR device440 including adistal region444 and having a distalatraumatic flange446.PMR device440 includes anouter tube448 defining anouter lumen450 within.Outer lumen450 includes within an intermediate orfirst tube452 defining an intermediate orfirst lumen454 within.Intermediate lumen454 includes within an inner orsecond tube456 defining an inner orsecond lumen458 within.Intermediate lumen tube452 extends distally and terminates in adistal injection tip462. Second orinner tube456 extends distally, terminating in adistal injection tip463.
• In one embodiment,first lumen454 is used to inject a drug throughneedle462. In this embodiment, second orintermediate lumen458 is used to inject a radiopaque dye through second orintermediate needle463. In the embodiment illustrated inFIG. 12A,intermediate tube452 can be slidably disposed within theouter tube444, and can haveinner tube456 slidably disposed within. In another embodiment, the functions of the first and second lumens are reversed relative to the aforementioned embodiment. In this embodiment,inner needle463 is used to inject dye, whileintermediate needle462 is used to inject a drug. Injecting a radiopaque dye or contrast media allows the treating physician to observe which areas of the heart wall have been treated and which have not been treated, under fluoroscopy.
• FIG. 12B illustrates aPMR device480 including adistal region484 and having a distalatraumatic flange486. A first material may be injected through a proximal manifold port, through afirst lumen492 defined within a first orintermediate tube490. The first material or fluid may be injected throughintermediate tube490, being injected into tissue through a firstdistal tip494. A second material or fluid may be injected through a second or inner manifold port, flowing through aninner lumen500 defined within aninner tube498. The second media may be injected distally into tissue through a innerdistal tip502.
• In the illustrated embodiment,tube490 is fixed relative toouter tube484, whileinner tube498 can be slidably disposed with respect totube490. In this embodiment, radiopaque contrast media may be injected at approximately the same site as a drug delivered in a PMR procedure. In one embodiment, a drug is injected throughinner tip502, while a contrast media is injected throughtip494. In another embodiment, contrast media is injected throughtip502, while a drug or other therapeutic substance is delivered through the outerdistal tip494. In the embodiment illustrated inFIG. 12B, outerdistal tip494 is relatively rounded at the end, with pressure being used to force material into the heart wall, rather than relying primarily on needle penetration.PMR device480 also allows injection of contrast media near the site of drug injection. This allows the treating physician to observe the location of sites treated by PMR under fluoroscopy, distinguishing the treated sites from the untreated areas.
• Numerous advantages of the invention covered by this document have been set forth in the foregoing description. It will be understood, however, that this disclosure is, in many respects, only illustrative. Changes may be made in details, particularly in matters of shape, size, and arrangement of parts without exceeding the scope of the invention. The invention's scope is, of course, defined in the language in which the appended claims are expressed.

Claims (12)

1. A catheter comprising:

an elongate shaft having a central longitudinal axis, a radial dimension extending outward from said central axis, and a distal region, wherein a plane bisecting said shaft through said longitudinal axis defines a shaft first portion and a shaft second portion opposite said shaft first portion; and

a radiopaque marker disposed in said shaft distal region, wherein said radiopaque marker is asymmetric about said bisecting plane, such that said catheter distal portion appears differently under fluoroscopy when viewed from an angle less than ninety degrees (90°) to said plane than when viewed from an angle greater than ninety degrees (90°) to said plane.

2. A catheter as inclaim 1, wherein said marker is asymmetric with respect to a transverse bisecting plane through said shaft and marker.

3. A catheter as inclaim 1, wherein said marker includes more than one region, and said regions are contiguous with each other.

4. A catheter as inclaim 1, wherein said marker includes a first portion transverse to said central longitudinal axis and a second portion parallel to said longitudinal axis.

5. A catheter as inclaim 1, wherein said marker includes more than one region, and said regions are not all contiguous with each other.

6. A catheter as inclaim 1, wherein said radiopaque marker includes a first arcuate portion disposed about said shaft and a second linear portion disposed along said shaft and substantially parallel to said shaft longitudinal axis.

7. A catheter as inclaim 6, wherein said first arcuate portion includes an annular portion about said shaft and contiguous with said second marker portion.

8. A catheter as inclaim 1, wherein said marker includes a first portion extending along said shaft length parallel to said central longitudinal axis and a second portion extending transversely to said shaft central axis.

9. A catheter as inclaim 8, wherein said shaft has a length and a circumference, wherein said marker first portion includes an arcuate shell extending along said shaft length in an annular fashion around less than all of said shaft length in an annular fashion around less than all of said shaft circumference, wherein said second marker portion is an annular band extending transversely to said central axis.

10. A catheter as inclaim 1, wherein said first marker portion includes a first arcuate shell on one side of said bisection plane, wherein said second marker portion includes a second arcuate shell disposed on the other side of said bisection plane relative to said first arcuate shell, wherein said first and second arcuate shells are disposed over different lengths on said shaft.

11. A catheter as inclaim 10, wherein said catheter shaft has a bend, and said marker is disposed proximal of said bend.

12. A catheter as inclaim 10, wherein said arcuate shells are substantially annular.

Images