IMPROVED DEVICE FOR ABLATION

Abstract

The current invention concerns a catheterization system For performing an Interventional ablation procedure comprising: a flexible guiding catheter comprising a distal end for Insertion and a proximal end for manipulation, the distal end of the guiding catheter transformable from a substantially elongated shape for passage within the vasculature into a contact shape for contacting internal tissue along a continuous band, the flexible guiding catheter comprising a guiding lumen, and a flexible ablation catheter comprising an ablation tip near a distal end, the ablation catheter insertable or inserted into the guiding lumen of the guiding catheter, characterized In that the guiding catheter comprises a continuous slit at or near the distal end of the guiding catheter, said silt arranged such that, when the distal end of the guiding catheter is in said contact shape and contacts internal tissue along a continuous band, the silt defines a functional opening between the guiding lumen and the internal tissue along said continuous band, through which slit said ablation tip is capable of ablating said internal tissue along said continuous band. The Invention further concerns a guiding catheter and an interventional ablation procedure.

Claims

1. Catheterization system for performing an interventional ablation procedure comprising: a flexible guiding catheter comprising a distal end for insertion and a proximal end for manipulation, the distal end of the guiding catheter transformable from a substantially elongated shape for passage within the vasculature into a contact shape for contacting internal tissue along a continuous band, the flexible guiding catheter comprising a guiding lumen, and a flexible ablation catheter comprising an ablation tip near a distal end, the ablation catheter insertable or inserted into the guiding lumen of the guiding catheter, characterized in that the guiding catheter comprises a continuous slit at or near the distal end of the guiding catheter, said slit arranged such that, when the distal end of the guiding catheter is in said contact shape and contacts internal tissue along a continuous band, the slit defines a functional opening between the guiding lumen and the internal tissue along said continuous band, through which slit said ablation tip is capable of ablating said internal tissue along said continuous band.

2. The catheterization system according to claim 1, wherein the guiding catheter comprises a self-expanding distal end, which is transformable from a substantially elongated shape for passage within the vasculature into a contact shape for contacting internal tissue along a continuous band.

3. The catheterization system according to claim 1, wherein the contact shape is a circumferential contact shape.

4. The catheterization system according to claim 1, wherein the contact shape comprises a helical shape, a spiral shape or an essentially circular shape.

5. The catheterization system according to claim 1, wherein the guiding catheter comprises one, two or more additional lumens.

6. The catheterization system according to claim 5, wherein at least one of the additional lumens comprises a sensing slit at or near the distal end of the guiding catheter, said sensing slit arranged such that the slit defines a functional opening between the additional lumen and the internal tissue.

7. The catheterization system according to claim 1, comprising a sensing catheter for sensing a variable at or near the targeted ablation zone.

8. The catheterization system according to claim 5, comprising a temperature sensing catheter.

9. The catheterization system according to claim 5, comprising a pressure sensing catheter.

10. The catheterization system according to claim 1, wherein the ablation catheter is a laser ablation catheter, an RF ablation catheter, a DC ablation catheter or a cryoablation catheter.

11. The catheterization system according to claim 1, wherein the guiding lumen comprises a cross section which is rotationally asymmetric around a longitudinal axis of the guiding lumen and wherein the ablation catheter comprises a cross section which is rotationally asymmetric around a longitudinal axis.

12. The catheterization system according to claim 1, wherein the ablation catheter telescopically fits an ablation positioning catheter, which comprises a distal end with an opening, the opening allowing the passage of at least the ablation tip of the ablation catheter.

13. A flexible guiding catheter comprising a distal end for insertion and a proximal end for manipulation, the distal end of the guiding catheter transformable from a substantially elongated shape for passage within the vasculature into a contact shape for contacting internal tissue along a continuous band, the flexible guiding catheter comprising a guiding lumen, and characterized in that the guiding catheter comprises a continuous slit at or near the distal end of the guiding catheter, said slit arranged such that, when the distal end of the guiding catheter is in said contact shape and contacts internal tissue along a continuous band, the slit defines a functional opening between the guiding lumen and the internal tissue along said continuous band, through which slit said ablation tip is capable of ablating said internal tissue along said continuous band.

14. Interventional ablation procedure comprising the steps of: inserting a flexible guiding catheter into vasculature of a patient, said guiding catheter comprising a guiding lumen and a continuous slit at or near a distal end of the guiding catheter; positioning the distal end of said guiding catheter at an ablation treatment zone and transforming the distal end of said guiding catheter into a contact shape, thereby contacting internal tissue along a continuous band, whereby said slit provides a functional opening between the guiding lumen and the internal tissue along said continuous band; inserting a flexible ablation catheter into the guiding lumen of said guiding catheter; ablating the internal tissue along said continuous band with said ablation catheter via said slit.

15. The catheterization system according to claim 2, wherein distal end comprises nitinol for allowing the transforming of the distal end in a self-expanding manner.

16. The catheterization system according to claim 11, wherein the rotational asymmetry of the ablation catheter is essentially of the same shape and size as the rotational asymmetry of the cross section of the guiding lumen.

17. The catheterization system according to claim 12, wherein the ablation tip can stick out of the slit in the guiding catheter and can come into direct contact with the internal tissue during ablation.

Description

DESCRIPTION OF FIGURES

[0028] FIGS. 1 to 6 show an ablation catheter according to the present invention from different viewpoints.

[0029] FIG. 7 shows a further embodiment of the present invention.

DETAILED DESCRIPTION or THE INVENTION

[0030] The present invention concerns a catheterization system for performing an Interventional ablation procedure and an interventional ablation procedure according to the claims and as further specified In this document.

[0031] Unless otherwise defined, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions are Included to better appreciate the teaching of the present invention. As used herein, the following terms have the following meanings:

[0032] “A”, “an”, and “the” as used herein refers to both singular and plural referents unless the context clearly dictates otherwise, By way of example, “a compartment” refers to one or more than one compartment.

[0033] “About” as used herein referring to a measurable value such as a parameter, an amount, a temporal duration, and the like, is meant to encompass variations of +/−20% or less, preferably +/−1.0% or less, more preferably +/−5% or less, even more preferably +/−1% or less, and still more preferably +/−0.1% or less of and from the specified value, in so far such variations are appropriate to perform in the disclosed Invention. However, it is to be understood that the value to which the modifier “about” refers is Itself also specifically disclosed.

[0034] “Comprise,” “comprising,” and “comprises” and “comprised of” as used herein are synonymous with “include”, “including”, “includes” or “contain”, “containing”, “contains” and are inclusive or open-ended terms that specifies the presence of what follows e.g. component and do not exclude or preclude the presence of additional, non-recited components, features, element, members, steps, known In the art or disclosed therein.

[0035] The term “rail” or “gutter” as used herein refers to a portion, preferably located at or near the distal end, of a guiding catheter comprising a slit, the portion being arranged to guide another catheter, e.g. an ablation catheter or a sensing catheter, along the slit.

[0036] The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within that range, as well as the recited endpoints.

[0037] In a first aspect, the invention provides catheterization system for performing an interventional ablation procedure. The system comprises a guiding catheter and an ablation catheter. A guiding catheter according to the present invention is shown in FIGS. 1 to 4.

[0038] In a preferred embodiment, the guiding catheter comprises a self-expanding distal end, which is transformable from a substantially elongated shape for passage within the vasculature into a contact shape for contacting internal tissue along a continuous band. In a preferred embodiment, the distal end comprises nitinol for allowing the transforming of the distal end in a self-expanding manner. Note that the self-expanding distal end is responsible for transforming the shape of the guiding catheter into the contacting shape, which preferably comprises a helical shape, a spiral shape or an essentially circular shape, but that the diameter of the guiding catheter is essentially fixed. The self-expanding distal end can hereby transform by curling up into such a preferred helical shape, spiral shape or circular shape, thereby leaving the diameter of the guiding catheter unchanged. A particularly preferred embodiment thus comprises a guiding catheter in which the distal end is provided with a nitinol wire or nitinol structure along at least a portion of the distal end of the guiding catheter, preferably provided essentially in a diametrically opposite half of the guiding catheter with respect to the slit, wherein the nitinol wire or structure comprises an unexpanded state In which it is substantially elongated for passage within the vasculature, and a deployed state defining the contact shape of the distal end of the guiding catheter, preferably the contact shape comprising a helical shape, spiral shape or circular shape. In an embodiment, the guiding catheter and/or the ablating catheter, and optionally all additional catheters such as sensing catheters, are steerable and/or deflectable. Steerable and deflectable catheters allow rotation and/or deflection resp. of at least the distal end of a catheter. Further, the catheters of the present invention may be steerable fixed-curve, bi-directional, 4-way deflectable, uni-directional or omnidirectional.

[0039] In a preferred embodiment, the catheterization system of the present invention may comprise a catheter-in-guide wherein at least one catheter is telescopically applicable or applied in another catheter. In FIG. 6, a lengthwise cross section of a catheterization system is shown which comprises a catheter-In-guide. In the shown embodiment, the ablation catheter telescopically fits an ablation positioning catheter, which can be inserted Into the guiding lumen of the guiding catheter either separately or simultaneously with the ablation catheter. The ablation positioning catheter comprises a distal end with an opening, the opening allowing the passage of at least the ablation tip of the ablation catheter, preferably such that the ablation tip can stick out of the slit in the guiding catheter and can come Into direct contact with the internal tissue during ablation. This cart be achieved by a guiding stop at the distal end of the ablation positioning catheter, which can guide the distal end of the ablation catheter with the ablation tip outwards, through the silk of the guiding catheter. With this embodiment, the length of the ablation catheter which sticks out of the silt, can be easily and accurately arranged proximally, which also allows an easy and accurate control of the pressure applied with the ablation tip to the internal tissue during the procedure. A continuous band can be ablated by essentially fixing the position of the ablation catheter with respect to the ablation positioning catheter in an ablative position, whereby the ablation tip sticks out of the slit and is in functional or direct contact with the internal tissue, and subsequently moving the ablation catheter and ablation positioning catheter along the lumen of the guiding catheter, such the ablation tip ablates a continuous band on the internal tissue as determined by the slit.

[0040] In preferred embodiments, the contact shape comprises a helical shape, a spiral shape or an essentially circular shape. In FIGS. 1 to 4, a contact shape comprising an essentially circular shape is Illustrated, a top view is presented in FIG. 4.

[0041] Preferably, the contact shape is selected taking into account the vessel or organ onto which the ablation is to be performed. In an embodiment, the contact shape may preferably be essentially circular. A circular shape can be preferred if a circumferential band needs to be ablated on the inner wall of a vessel, such as is the case for ablation in the antrum of a pulmonary vein to achieve PVI. A circular shape may also be preferred in case a surrounding band needs to be ablated on an organ wall around the entry or exit of a vessel, such as can be the case for ablation In the ostium of a pulmonary vein for achieving PVI, the ablation band thereby surrounding the entry of the pulmonary vein in the left atrium. In this latter case, a spiraling shape may also be preferred. A helical shape may be preferred if a helical band needs to be ablated on the inner wall of a vessel, such as is the case for ablation in a renal artery to treat arterial hypertension,

[0042] The silt comprises a length as measured along the guiding catheter, and a width as measured in an essentially azimuthal direction with respect to the guiding catheter. By definition, the slit is longer than it is wide. The width of the slit may vary along its length, but preferably the width of the silt is essentially constant along its length. Preferably, the slit comprises a length of at least 1 cm, more preferably at feast 1.5 cm, still more preferably at least 2 cm, yet more preferably at least 3 cm, at least 4 10 cm, at least 5 cm, at least 6 cm or even longer. Possible lengths of the slit are 1.0 cm, 1.1 cm, 1.2 cm, 1.3 cm, 1.4 cm, 1.5 cm, 1.6 cm, 1.7 cm, 1.8 cm, 1.9 cm, 2.0 cm, 2.1 cm, 2.2 cm, 2.3 cm, 2.4 cm, 2.5 cm, 2.6 cm, 2.7 cm, 2.8 cm, 2.9 cm, 3.0 cm, 3.1 cm, 3.2 cm, 3.3 cm, 3.4 cm, 3.5 cm, 3.6 cm, 3.7 cm, 3.8 cm, 3.9 cm, 4.0 cm, 4.1 cm, 4.2 cm, 4.3 cm, 4.4 cm, 4.5 cm, 4.6 cm, 4.7 cm, 4.8 cm, 4.9 cm, 5.0 cm, 5.1 cm, 5.2 cm, 5.3 cm, 5.4 cm, 5.5 cm, 5.6 cm, 5.7 cm, 5.8 cm, 5.9 cm; 6.0 cm, 6.1 cm, 6.2 cm, 6.3 cm, 6.4 cm, 6.5 cm, 6.6 cm, 6.7 cm, 6.8 cm, 6.9 cm, or any value there between or even higher than 7 cm. Preferably, the silt comprises a width which is smaller than 1 cm, more preferably smaller than 0.8 cm, still more preferably smaller than 0.5 cm, Possible widths of the slit are 1 cm, 0.9 cm, 0.8 cm, 0.7 cm, 0.6 cm, 0.5 cm, 0.4 cm, 0.3 cm, 0.2 cm, 0.1 cm or any value therebeteween or even smaller than 0.1 cm. In embodiments wherein a circumferential band needs to be ablated on the Inner wall of a vessel, such as is the case for ablation in the antrum of a pulmonary vein to achieve PVI, the slit comprises a length which is at least as long as the circumference of the of the vessel.

[0043] In an embodiment, the ablation catheter is a contact ablation catheter, i.e. it ablates tissue by direct contact of the ablation tip with the tissue. A contact ablation catheter can for instance be a heating catheter comprising an ablation tip which ablates tissue by direct heat transfer from ablation tip to tissue. In embodiments where the ablation catheter is a contact ablation catheter, the slit comprises a width which is larger than a width of the ablation tip of the contact ablation catheter in order to allow passage of at least a portion of the ablation tip through the silt.

[0044] In an alternative embodiment, the ablation catheter is a contactless catheter, i.e. it ablates tissue without direct contact of the ablation tip with the tissue. In such an embodiment, the slit may comprise a width which is larger than a width of the ablation tip of the contactless ablation catheter but preferably, the slit comprises a width which is smaller than a width of the ablation tip of the contactless ablation catheter

[0045] In related embodiments, it is the Intention to subsequently use more than one ablation catheter, e.g. a contact ablation catheter and, subsequently or prior, a contactless ablation catheter. This can be done using the same guiding catheter. The present invention thus relates to a system as described in this document, the system comprising a plurality of ablation catheters which are each insertable into the guiding lumen of the guiding catheter. The plurality of ablation catheters may comprise a contact ablation catheter and a contactless ablation catheter. In such embodiments, the ablation tip of the contact ablation catheter is smaller than a width of the slit and the ablation tip of the contactless ablation catheter is preferably larger than a width of the silt.

[0046] In a preferred embodiment, the guiding catheter comprises exactly one slit defining a functional opening between the guiding lumen and the internal tissue along the continuous band, through which slit the ablation tip is capable of ablating said internal tissue along the continuous band. In an alternative embodiment, the guiding catheter comprises a plurality of slits, e.g. two, three, four or more slits, provided at least partially adjacent to each other along the guiding catheter. Such an embodiment allows for instance a double continuous band to be ablated In a single procedure using one, two or more ablation catheters.

[0047] In an embodiment, the slit is located on the outward-lying side of the guiding catheter when the distal end of the guiding catheter has the contact shape (see FIG. 1). Such a silt allows essentially circumferential or partially circumferential bands to be ablated on the walls of a vessel. Hereby, the distal end of the guiding catheter in an elongated shape can be inserted into the vessel, subsequently the distal end of the guiding catheter can be transformed in an at least partially circumferential or helical contact shape. As the silt is located on the outward-lying side of the guiding catheter, the slit automatically faces the vessel's inner wall, which allows an easy and accurate subsequent ablation along an at least partially circumferential or helical band.

[0048] In another embodiment, the slit is located on the distal-lying side of the guiding catheter when the distal end of the guiding catheter has the contact shape (see FIG. 5). Such a slit allows essentially circular, spiraling, partially circular or partially spiraling bands to be ablated on the walls of an organ, preferably said band surrounding the entry or exit of a vessel into or out off said organ. Hereby, the distal end of the guiding catheter in an elongated shape can be inserted into the organ, subsequently the distal end of the guiding catheter can be transformed in an at least partially circular or spiraling contact shape. As the slit is located on the distal lying side of the guiding catheter, the slit automatically faces the organ's wall, preferably the silt at least partially surrounding the entry or exit of a vessel, e.g. the silt preferably facing the ostium of a vessel, which allows an easy and accurate subsequent ablation along an at feast partially circular or spiraling band.

[0049] The guiding catheter comprises at least a guiding lumen. In a preferred embodiment, the guiding catheter comprises one, two or more additional lumens. These additional lumens may comprise a sensing slit at or near the distal end of the guiding catheter, said sensing slit arranged such that the slit defines a functional opening between an additional lumen and the Internal tissue. In FIGS. 2A and 2B, a guiding catheter with two additional lumens is shown in detail. These lumens preferably allow other catheters to be positioned with a distal end at or near the targeted region, preferably said other catheters comprising sensors. In a particularly preferred embodiment, the guiding catheter comprises a pressure sensing lumen and/or a temperature sensing lumen. Herein, the pressure sensing lumen allows to position a pressure sensing catheter with a distal end at or near the targeted ablation region and the temperature sensing lumen allows to positron a temperature sensing catheter with a distal end at or near the targeted ablation region.

[0050] In a preferred embodiment, the catheterization system comprises a sensing catheter for sensing a variable at or near the targeted ablation zone. In a particularly preferred embodiment, the system comprises a pressure sensing catheter and/or a temperature sensing catheter. Sensing catheters preferably comprise one or more sensors at or near a distal end of said sensing catheters, e.g. a pressure sensing catheter preferably comprises pressure sensor at its distal end and a temperature sensing catheter preferably comprises a temperature sensor at its distal end. These embodiments are preferably combined with a guiding catheter comprising one, two or more additional lumens as described here above. Sensing can be performed before, during and/or after the procedure.

[0051] In a preferred embodiment, the distal end of the guiding catheter comprises an end cap closing off at least the guiding lumen and optionally the additional lumens, to prevent the ablation catheter and optionally sensing catheters from being inserted too far. This is shown in detail In FIGS. 3A and 3B.

[0052] In a preferred embodiment, the ablation catheter is a laser ablation catheter, an RF ablation catheter, a DC ablation catheter or a cryoablation catheter.

[0053] In a preferred embodiment of the invention, the guiding lumen comprises a cross section which is rotationally asymmetric around a longitudinal axis. Herein, the longitudinal axis refers to an axis oriented along the catheter, essentially through the geometrical center of the crass sections the lumen slang the catheter. For instance, the guiding lumen may have an essentially elliptical, triangular or rectangular cross section. Preferably in combination herewith, the ablation catheter preferably comprises a cross section which is rotationally asymmetric around a longitudinal axis, the rotational asymmetry being essentially of the same shape and size as the rotational asymmetry of the cross section or the guiding lumen. With such rotationally asymmetric cross sections, the ablation catheter is prevented to rotate within the guiding lumen during insertion into the guiding catheter, ensuring a better control of the ablation tip of the ablation catheter at the position of the distal end of the guiding catheter and thereby at the position of the silt. This embodiment is particularly preferred if the ablation catheter is a laser ablation catheter. In this case the ablation tip may comprise an outwardly oriented laser output region, i.e. a region where laser light is arranged to come out from the ablation tip In the direction of the slit towards the targeted tissue.

[0054] In an embodiment, the slit is open. In cases where the ablation catheter is arranged for ablating tissue by contacting the tissue with the ablation tip, such an open slit is necessary. Such can be the case for cryo-ablation, RF or DC ablation. In such cases it is also preferred that the ablation tip is of such dimensions that at least part of the ablation tip sticks out of the slit in order to contact the tissue, such as illustrated in FIG. 5.

[0055] In an alternative embodiment, the slit is at least partially dosed off fluidically, i.e. the slit does not or only partially allow fluid, e.g. blood, to be exchanged between the guiding lumen and the patient's body, e.g. the patient's vasculature. This embodiment can be preferred in cases where the ablation catheter is arranged contactless ablation, as can be the case for laser ablation or thermal ablation. For laser ablation in particular, the slit may be functionally open for the laser light by being transparent. For thermal ablation, the slit may be functionally open by comprising material of low thermal resistance.

[0056] In a preferred embodiment, at least one of the additional lumens is arranged for applying cooling liquid, preferably along the length of the guiding catheter, to cool the guiding catheter, and optionally the ablation catheter or other catheters, e.g. sensing catheters, during the procedure. The cooling liquid may also be used to cool the blood and/or vasculature along the guiding catheter during the Interventional procedure.

[0057] In a preferred embodiment, at least one of the additional lumens comprises one or more fluid openings at or near the distal end of the catheter and/or along, which fluidically connect the additional lumen to the vasculature for allowing transfer or exchange of fluids between vasculature and the additional lumen. Such additional lumen may be used for Introducing fluids Into the vasculature far treatment purposes, e.g. fluids comprising active substances, or cooling purposes, e.g. for cooling down the blood or the internal tissue or vasculature.

[0058] In an embodiment, the proximal end of the ablation catheter is directly or indirectly connected to an engine for moving the ablation catheter along the guiding lumen of the guiding catheter. Such an engine allows to better control the movement of the ablation catheter and thereby also the ablation tip. In particular during ablation of the internal tissue. Preferably, the ablation catheter can be rimed at an essentially constant speed, thereby allowing the achievement of a very regular ablation over the entire ablation band.

[0059] A further embodiment of the present invention is shown in FIG. 7. Here the catheter system comprises a sconce or entrenchment device which is proximally manipulable, preferably by a pullback wire which is preferably connected to a pullback system. The entrenchment device is preferably positioned near the distal end of the slit in the beginning of the procedure and comprises a slanted portion with respect to the longitudinal direction of the guiding catheter, such that an ablation catheter's tip is forced outwards towards and preferably through the slit when It is pushed distally. The entrenchment can be pulled back while the ablation catheter is not such that the ablation catheter's tip is pushed further outwards, or the entrenchment can be pushed without moving the ablation catheter such that the ablation tip is retracted inwards. Alternatively, ablation catheter and entrenchment device can be manipulated similarly such that the ablation is performed along the slit with the distance between the ablation tip and the guiding catheter's outer wall being the same during the procedure.