Innovations & Inventions

Endocardial catheter system for Wavelength measurement, Mapping and ablation

Inventor(s): ABDOLMOHAMMADI AKBAR (FR)

Applicant(s):   ABDOLMOHAMMADI AKBAR (FR)

Classification:  -international:      A61B18/14; (IPC1-7): A61B17/39

                           -cooperative:        A61B18/1492

Application number:       WO1998IB01737   19981031

Priority number(s):          WO1998IB01737   19981031

Also published as:            EP1123046 (A1)    EP1123046 (B1)     CA2348558 (A1)

                                             AU9554898 (A)      DE69835838 (T2)

 

                                          Abstract of WO 0025685 (A1)

The present invention relates to a catheter system comprising: an elongated tubular member (111) with a plurality of lumens and electrical conductors threaded there through from proximal to distal extremity. The lumens are either inflation lumens or great lumens allowing other catheters moving slidably thereon, a head portion which has one or a plurality of arms (112, 113) having proximal and distal extremities. The proximal extremity of the arms are connected to the distal extremity of the elongated member. There are a plurality of longitudinally spaced-apart electrodes (115, 117) provided on each arm and connected to conductors of the elongated member. The head portion undergoes an expanded and a contracted position by an expanding system (114), a stabilizing system (116) bonded to the head portion having a contracted and expanded position. In expanded position, this system applies firmly the working head to the cardiac wall under investigation.

A high quality text as facsimile in your desired language may be available amongst the following family members:

CA2348558 (A1)         DE69835838 (T2)          EP1123046 (B1)

ENDOCARDIAL CATHETER SYSTEM FOR WAVELENGHT MEASUREMENT, MAPPING AND ABLATION

  • Background of the invention

 The present invention relates generally to the field of the diagnosis and ablation using steerable vascular catheters. The invention is particularly directed to cardiac wavelength measurement and an ablation catheter system capable of creating linear lesions in the atrial wall.

  • Discussion of the related art:

Dr. Cox & al, have described an empirical surgical technique called the MAZE operation in which a series of incision produce a segmentation of atrial tissue which could cure the majority of patients, however, the percentage of patients who do not benefit from this operation is far from negligible.

The efficiency of this operation is explained by the relation between the critical mass (the minimum width of a given atrial tissue under which the fibrillation is impossible) and the wavelength. The critical mass itself depends on the wavelength of the atrial tissue. In other words the greater the wavelength measured, the greater the width of tissue in which the fibrillation is impossible, this principal is represented by the following formula RWL = WL/CM (where WL = wavelength, CM = critical mass, defined as the width of tissue below which the fibrillation is impossible, RWL = relative wavelength). As we can see there is a linear relation between the critical mass and the wavelength, the limit of the normal and pathological zone is defined by this line and the determinant element is the RWL.

This means that each time the width of the tissue is below the critical mass, the fibrillation stops on the contrary, when it is above this value, it continues. This explains the failure of the MAZE operation in some patients. The MAZE operation is a serious surgical act with pain, a long stay in hospital and multiple complications. Many have tried to use this technique by radiofrequency catheter ablation, however, the results have been disappointing. Not only does the procedure remain empirical (without measurement of the wavelength and the mass), but also, the creation of complete ablation lines is very difficult.

Undoubtedly, this is the result of a mediocre stability of ablation catheters actually available on the one hand, and the impossibility of effecting trans mural lesion on the whole route with the same catheter and in the same condition on the other.

It is obvious that the number of lines to be created by radio frequency ablation is dependent on the above parameters, so the measurement of the size of the atria (by echocardiography or by angiography). The wavelength and the appreciation of the anisotropy seems essential for an appropriate ablation of the fibrillation and some types of flutter.

The measurement of these parameters can also be helpful in the diagnosis of these arrhythmias when they are undiagnosed by classical means. For example rare episodes and, or, occurrence in some special circumstances. Also, for the evaluation of the mechanism or action of the drugs or other research programs this can be helpful.

The major problem for the measurement of the WL is the conduction velocity because the knowledge of the direction of the conduction velocity is essential for it’s appropriate evaluation.

The WL has been measured in dog atria after thoracotomy by SMEETS & al using the parallel electrodes and adjusting these electrodes in a manner to have parallel recordings to confirm the direction on the propagation.

In clinical settings there is no known techniques for the measurement of the wavelength. The provision of a WL measuring and ablation catheter system that can successfully treat atrial fibrillation and some types of atrial flutters, be readily creating linear continuous lesions in the atria, would represent a definite advance in the treatment of these conditions.

Accordingly, it is a primary object of the invention to provide a multielectrode catheter shape, easily deployed directly, or from main catheters or sheaths that provides shapes capable of adapting to varying contours of the atria and keeping a full stability until the end of the linear ablation procedure. Another object is to provide catheter shapes, which are easily deployed directly, or from main catheters or sheaths that provide shapes capable of adapting to varying contours of the atria and maneuvered to contact measurement can be taken.

A further object is to provide a catheter system, which is easily deployed directly or from main catheters that provide shapes capable of adapting to varying contours of the heart chambers and sustaining contact so that the anisotropy of conduction can be appreciated.

Other objects and advantages of the invention will become apparent to those skilled in the art with the art with the descriptions and figures of this specification.

  • Summary of the invention:

By means of the present invention, an array of distal working catheter shapes is provided, which are easily deployed to contact the inner wall surfaces of the cardiac chambers in a manner that allows them to adapt completely to endocardial surfaces of the cardiac chambers and enables easy recording of impulses of the ablation procedures.

In one aspect, the invention features an ablation system including:

– an elongated flexible, hollow catheter shaft having a plurality of lumens extending longitudinally from the proximal to the distal extremity. At least one of the lumens is connected to a screw syringe by an inflation port. One of the lumens is a large one allowing a special working catheter with radiofrequency delivering electrodes to move slid ably therein.

– an ablation head comprising a hollow catheter in continuity with the said catheter shaft wherein a plurality of longitudinally spaced-apart incomplete ring-form electrodes are incorporated.

– a stabilizing system which is a ring-like thin balloon made of a very compliant material attached to the working head of said catheter and connected to an inflation lumen.

The operator can stabilize the working head segment by inflating the ring from balloon in order to fix the head portion against the atrial wall. After the stabilization of the tip portion by changing the position of the radio frequency delivering 40 electrodes, one can realize a linear ablation without moving the head portion of the main catheter.

It is also possible to verify the perfect continuity of the ablation line before moving the so-called head.

In another embodiment the stabilizing system includes:

-a cylindrical balloon attached to the distal and proximal extremities of the head portion which forms an arc when expanded, containing a plurality of cylindrical structures (bridges) extending between the ablation head and the arc-form balloon. These cylinders are linked separately to the inflation ports so that the operator can improve the contact between the ablating head and the atrial wall by increasing the pressure of each individual bridge as necessary in order to compensate for any bulges in the wall.

Association of each of the catheter system described above with a cooling system which includes: two lumens in the catheter shaft by one of which the cooling solution is introduced to the head portion and by the other one it is drained.

In another embodiment the invention features a catheter system including:

-an elongated, flexible catheter shaft having a plurality of lumens, one of which is a large one and wherein an ablation catheter can slid ably move and the others are inflation lumens.

-an ablation head comprising a catheter in continuity with the catheter shaft which has a slotted opening. The electrodes of the ablation catheter will be applied directly to the atrial wall by this opening.

-a stabilizing system which is a ring-form very expandable thin balloon connected to a screw syringe by an inflation lumen and attached to the working head in the opposite side of the slotted opening.

In another embodiment the ablation catheter includes:

-an elongated, flexible catheter shaft having an inflation lumen extending from the proximal inflation port to the distal inflation port with a plurality of electrical conductors extending from the proximal extremity to the electrodes on the head portion situated on the distal tip.

-an ablation head comprising of a catheter in continuity with the catheter shaft wherein a plurality of longitudinally spaced-apart ring-form electrodes are incorporated and each electrode is connected by an insulated conductor to a radiofrequency delivering source.

-a stabilizing system, which is the same as described above.

In another embodiment:

There are two expandable arms provided on each side of the ablation head with sensing electrodes in their tips. In the contracted position these arms are very thin and are parallel to the axis of the head. In the expanded position they are perpendicular to the direction of the ablating head, and in this position the sensing electrodes are equidistant on each side. There is also a special catheter provided, having a plurality of electrodes with sensing capability which can move slid ably in the head portion.

This assembly enables to find the direction of the conduction velocity by changing the position of the catheter and evaluating the velocity between the recording of the electrodes of the head portion and the lateral arms.

In another aspect, the invention features an atrial wavelength measuring system which includes:

-an elongated, flexible catheter shaft incorporating a plurality of electrical conductors, extending from the proximal extremity of the elongated, flexible catheter shaft to the distal extremity. There are a plurality of inflation lumens extending longitudinally through it, coupling screw syringes through proximal inflation ports to the distal inflation ports which are connected to inflatable structures of the stabilizing system.

-a wavelength measuring head composed of: three arms having an expanded position and a contracted position. In the expanded position, the three arms are parallel and have a predetermined distance between them.

The expanded position is secured by thin cylindrical balloons of approximately one mm diameter made of a very strong, non-stretchable resinous material extended between the arms. Thereby providing a plurality of longitudinally spaced-apart electrodes on each arm and a plurality of conductors threaded wherein.

-a stabilizing system which is a ring-like balloon made of a very compliant material bonded to the central arm. In an expanded position the free part of the ring-like balloon backs up against the atrial wall and applies the WL measuring head to the opposite atrial wall under investigation.

In one embodiment the so-called arms are similar and constructed like classical catheters.

In another embodiment the wavelength measuring head includes: a central rigid arm and a plurality of inflatable arms made of a very strong low non-stretchable material in which the precise interelectode distance is possible by accurate dosing of the inflation pressure.

In another embodiment the wavelength measuring head is composed of:

-one central classical catheter, whereon a plurality of longitudinally spaced-apart electrodes are provided.

-a plurality of inflatable arms on each side of the central arm having an extremely contracted position and an expanded position in which the lateral arms are perpendicular to the central arm. There are a plurality of electrodes on each arm having a predetermined distance between one another and the electrodes of the central arm in the expanded position. Each arm is connected to a screw syringe by an inflation lumen threaded in the elongated flexible member.

-a stabilizing system which is a ring-form thin balloon made of a highly elastic material connected to a screw syringe by an inflation lumen.

In another embodiment the wavelength measuring head includes:

-three arms each having a determined number of electrodes and an interconnected proximal extremity. In the contracted position, the arms are parallel and in the expanded position they form a fan-like structure. The expanded position is secured by fine, expandable, cylindrical balloons which connect the distal extremity of the arms. This system, when expanded, changes the position of the lateral arms and extends them more and more. A very flexible part is provided in the proximal extremity of each arm for easy bending. Each arm can realize the measurement of the CV in all direction in one quadrant (90) so the provision of a complete mapping of the WL for 180 in one direction is possible (i. e. by stimulation of the proximal electrodes and recording of the distal electrodes) and 180 in the other direction (l. e. by stimulation of the distal electrodes and recording of the proximal electrodes).

In another embodiment: the arms are auto-expandable with a plurality of electrodes. The main catheter supporting the terminal part is applied to the cardiac wall by the supporting system described above.

In another embodiment the working head is a mapping head which is composed of:

-a plurality of longitudinally spaced-apart inflatable arms having an interconnected proximal extremity. These arms have a contracted very thin diameter and expanded position.

There are a plurality of longitudinally spaced-apart electrodes provided on each arm which are connected by a plurality of insulated conductors threaded in the arms and the elongated catheter shaft to a console. These arms are connected to screw syringes by inflation lumens.

-an expanding system which is a very cylindrical balloon made of a highly elastic material interconnecting the distal extremities of the arms. The expanding system is connected to a screw syringe by an inflation lumen.

By the infusion of a solution the expanding system is progressively inflated and the arms progressively extended.

-a stabilizing system (a ring-like, very thin balloon linked to the central arm and connected to a screw syringe by an inflation lumen. In the expanded position the stabilizing system backs up on the opposite wall of the cardiac chamber and applies the working head firmly to the wall under investigation.

In another embodiment there is a separate stabilizing system provided composed of:

-an elongated, flexible, catheter shaft having proximal and distal extremities. There are a plurality of lumens provided in the catheter shaft, one which is a large one and in which a relatively rigid central arm can slide between a shortened and an elongated position.

-a plurality of arms having proximal and distal extremities. The proximal extremity of the arms is connected to the distal extremity of the elongated catheter (main catheter) and their distal extremities to the distal extremity of the central arm. The arms have a contracted and an expanded position. The arms are thin, cylindrical balloons made of a relatively rigid low-elasticity material connected to screw syringes by inflation lumens threaded in the main catheter shaft. By changing the position of the central arm, the operator can define the shape of the head. A perfect application of the catheter head against the wall under study can be achieved by altering the position of the central arm and simultaneously regulating the pressure on the appropriate arm of the head portion.

In another embodiment the separate stabilizing system is composed of:

-an elongated, flexible, catheter shaft having proximal and distal extremities. There are a plurality of lumens provided in the catheter shaft, one of which is a large one and in which a relatively rigid central arm can slide between a shortened and an elongated position.

-there arms having proximal and distal extremities. The proximal extremity of the arms are connected to the distal extremity of the elongated catheter shaft and their distal extremity to the distal extremity of the central arm. Two of the arms are linked by a highly elastic sheet; allowing easy application of catheters having a unique member.

This stabilizing system can be associated to any of the working heads described above or can be a network of branches carrying a plurality of electrodes allowing any kind of measurements.

                               Brief Description of the Drawings

FIG.1 is a schematic illustration of an ablation system with a hollow catheter probe incorporating the present invention.

FIG.2 is a side view of the distal proportion of the ablation head with a stabilizing system in expanded position.

FIG.3 is an enlarged cross-sectional view taken along the line 7C-7C of FIG. 1.

FIG.4 is an enlarged cross-sectional view taken along the line 7B-7B of FIG. 1.

FIG.5 is an enlarged cross-sectional view taken along the line 7A-7A of FIG. 1.

FIG.6 is a schematic illustration of the working head of an ablation system having a wavelength measuring capacity, in which a plurality of expandable lateral arms allow the determination of the direction of the conduction velocity.

FIG.7 is an enlarged side view of the ablation head with the stabilizing system having a plurality of bridges in an expanded position.

FIG.8 is an enlarged cross sectional view taken along the line 7C-7C of a catheter shaft having a plurality of conductors connected to the electrodes of the working head.

FIG.9 is an enlarged cross-sectional view taken along the line 12-12 of a catheter shaft having a large lumen in which an ablation catheter can move slid ably with wavelength measuring capacity.

FIG.10 is an enlarged cross-sectional view taken along the line 14-14 of an ablation system having a hollow catheter and a working head with a stabilizing system including a plurality of bridges.

FIG.11 is a pictorial representation of the catheter of FIG 1 in the right atrium with the stabilizing system in an expanded position taking back up on the septum and pushing the ablation head to the wall under ablation.

FIG.12 is an enlarged side view of catheter system having two ablation catheters with the stabilizing system in an expanded position.

FIG.13 is an enlarged side view of the ablation head with a slotted opening and the stabilizing system in an expanded position.

FIG.14 is an enlarged cross-sectional view taken along the line 30-30 of an ablation system having a hallow catheter shaft and a double ablation catheter.

FIG.15 is an enlarged cross-sectional view taken along the line 42-42 of the FIG 17.

FIG.16 is an enlarged view of the working head (part 31 of FIG 17) in a contracted position.

FIG.17 is a schematic illustration of a wavelength measuring system with a working head constructed of three longitudinally spaced-apart arms which are parallel in an expanded position.

FIG.18 is an enlarged lateral cross-sectional view taken along the line 54-54 of FIG 20.

FIG.19 is an enlarged lateral view of the head portion (31 of FIG 17) in a partly expanded position.

FIG.20 is a schematic illustration of a wavelength measuring system with a working head having a central classical arm and two lateral inflatable arms.

FIG.21 is an enlarged cross-sectional view taken along the line 65-65 of FIG 22.

FIG.22 is a schematic illustration of a wavelength measuring system with a working head having a central classical arm and a plurality of inflatable lateral arms which are perpendicular to the central arm in an inflated position.

FIG.23 is a pictorial representation of the catheter of FIG 1 in the left atrium with the stabilizing system in an inflated position taking back up on the septum and pushing the ablation head to the wall under ablation.

FIG.24 is a schematic presentation of the position of the electrodes on the catheters of FIG 17-20-22.

FIG.25 is an enlarged cross-sectional view taken along the line 79-79 of the FIG 26.

FIG.26 is a schematic illustration of a wavelength measuring system with a working head having three parallel which are fan-shaped in an expanded position.

FIG.27 is a schematic illustration of a mapping head.

FIG.28 is a schematic illustration of a wavelength measuring system with a working head having 9 parallels arms which are fan-shaped in an expanded position.

FIG.29 is an enlarged cross-sectional view taken along the line 85-85 of FIG 27.

FIG.30 is an enlarged cross-sectional view taken along the line 94-94 of FIG 28.

FIG.31 is a schematic view of a separate stabilizing catheter system with a head comprising three lateral arms with a membrane 102 between two of them. The lateral arms are represented in an expanded position.

FIG.32 is an enlarged longitudinal view of the head portion of the catheter of the FIG 31, showing the different position of the lateral arms 103 by dotted lines depending on the position of the central member 101.

FIG.33 is an enlarged longitudinal cross-sectional view of the elongated flexible member of the catheter of FIG.31 showing the central member 101 and inflation lumens 106 and the large central lumen 107.

FIG.34 is the head portion of a separate stabilizing system with a plurality of lateral arms in an expanded position.

FIG.35 is an enlarged cross-sectional view taken along the line 104-104 of a separate stabilizing system having 4 lateral arms.

 FIG.36 is a schematic view of a wavelength measuring system with both the expanding system and the stabilizing system in an expanded position.

                                  Detailed description of the invention:

The present invention relates to catheter probes for introduction into a chamber of the heart having blood therein and formed by a wall through a lumen leading to the chamber.

Generally, the catheter system is comprised of three main co-operating components including:

-a flexible elongated tubular member having proximal and distal extremities.

-a distal working catheter portion (called the working head).

-a stabilizing system which assures a high stability profile to the working head.

FIG.1 shows generally one embodiment having a working head with ablation capabilities comprising:

-an elongated hollow catheter shaft 4 having two lumens 8,9 (FIG 3) extending longitudinally from the proximal to the distal extremity. One of the lumens 9 is connected to a screw syringe 5 by an inflation port and the other lumen 8 is a large one. Allowing a special working catheter 6 with ablation capability to move slidably wherein.

-a working head I including a hollow catheter in continuity with the tubular member wherein a plurality of incomplete ring-form electrodes 10 are incorporated. The inter electrode distance is 0.5 to 4 mm and the electrodes are 4 mm in length.

-a stabilizing system 3 which is a ring-like, very expandable balloon connected to inflation lumen 9 and attached to the working head.

After positioning the catheter under fluoroscopy the physician can stabilize the head by inflating the ring-like structure with a radiopaque solution and by changing the direction of the x-ray beam he can determine the maximum diameter of the circle formed by the said ring and if he desires two, three, ablation lines he can determine the same distances between the lines by the determination of the angle of the beam and the greatest diameter of the said ring.

FIG.7 shows another embodiment with a working head composed of:

-a stabilizing system with an arc-shaped, cylindrical balloon 13 attached to the proximal extremity and the distal extremity of the head portion and a plurality of cylindrical bridges 17 between the catheter shaft and the arc-shaped balloon.

This can help the physician stabilize the catheter head perfectly, especially in parts where the atrial wall has bulges limiting an optimal contact between the catheter and the atrial wall.

FIG.6 shows another embodiment in which the working head includes:

-a catheter shaft in continuity with the tubular member wherein a plurality of incomplete ring-form electrodes are incorporated.

-a stabilizing system which is a ring-form, very expandable structure connected to an inflation port.

-a plurality of lateral arms 11 having an expanded position and a contracted position. When contracted they have a very small size and are parallel to the axes of the catheter shaft. Sensing electrodes are provided at their tips and when expanded the said electrodes have equal distances from the catheter shaft. The physician can find the direction in which the recording of these electrodes are parallel. This direction could be considered at the direction of the propagation of the depolarization. At this moment he can measure the velocity by introducing a working catheter with a plurality of sensing electrodes each with a predetermined distance matching the electrodes of the head portion. The same catheter can be employed to ablate by using a radiofrequency delivering catheter which can slide in the said catheter shaft.

In another embodiment there is a cooling system provided comprising of an infusion port extending through the elongated flexible catheter shaft to the distal infusion port. The cooling solution either enters the blood flow (if the catheter head is open) or is pumped by a distal extraction port to an extraction lumen extending through the catheter shaft to a proximal extraction port.

In another embodiment the ablation catheter includes:

-an elongated, flexible, catheter shaft(FIG8) comprising a plurality of inflation lumens and a plurality of separated insulated leads 15 extending from the proximal extremity to the distal extremity. Each lead is separately connected to an electrode in one hand and to a radio frequency delivering system on the other hand.

-a working head comprising a catheter shaft in continuity with the elongated flexible catheter shaft, with a plurality of incomplete ring-form electrodes, which are connected separately to insulated leads.

-a stabilizing system composed of a ring-form, very thin structure constructed of a very expandable material allowing the stabilization of the head in the manner described earlier. The physician, by connecting the leads separately, or in gang, can apply the ablation and in the end of the first round of the ablation can verify the perfect continuity of the created line and can reablate the parts where the ablation has been incomplete.

FIG. 11 represents schematically the catheter head 19 applied firmly to the lateral wall of the right atrium by the stabilizing system 18 in an expanded position.

FIG. 12 shows another embodiment in which the ablation head includes:

-a stabilizing system formed of a ring-form, very expandable balloon 29 connected to a screw syringe by an inflation lumen27.

-two hollow catheters 28 encircling the stabilizing system in which an ablating catheter can slid ably move allowing the ablation of two lines at the same time.

FIG. 13 shows anther embodiment in which the ablation head includes:

-a hollow catheter in continuity with the elongated tubular member which has a slotted opening 25 allowing the electrodes 23 of the ablation catheter 24 to be applied directly to the cardiac wall.

-a stabilizing ring-form balloon 3 bonded to the head portion in the opposite side of the slotted opening.

FIG. 17 is a general view of a wavelength measuring catheter comprising:

-an elongated, flexible, catheter shaft 32 with a plurality of inflation lumens 43 and a plurality of insulated conductors 44 extending from the proximal extremity to the distal extremity.

-a plurality of longitudinally extending spaced-apart arms having interconnected proximal extremities and carried by the distal extremity of the flexible elongated tubular member. The said arms are moveable between a contracted position (FIG16) and an expanded position (FIG17). The means are provided for moving the arms between a contracted and expanded position. In the expanded position, the wavelength measuring head 31 has a predetermined form allowing the wavelength measurement in a precise manner. A plurality of longitudinally spaced-apart electrodes 36 are provided on each arm and are connected to a plurality of conductors 44 extending through a lumen provided in the flexible elongated member. The conductors 44 are connected to cables 38 which are connected to a control console and power supply.

-a stabilizing system is provided to apply the WL measuring head firmly to the heart wall under investigation. The said means is moveable between a contracted (small size) and an expanded position (FIG 19). When expanded the said stabilizing means backs up on the contra lateral wall of the atrium and applies firmly the so called head to the wall under investigation.

In one embodiment (FIG 17) the so-called head 31 consist of:

-three arms, longitudinally spaced-apart, having interconnected proximal extremities in which the lateral arms are connected to the central one by cylindrical, thin, very low elasticity balloons in proximal 34 A and distal 34 B extremities. Said balloons are coupled to inflation ports 37 through inflation lumens extending along the length of catheter shaft 43. Balloons 34 A and 34 B are inflatable with fluid preferably by a radiopaque solution which is inject by a syringe at the balloon inflation ports 37. By increasing the volume of the balloons the arms are separated and pressures are dosed in such a manner that the structure has three parallel arms with a distance of approximately 1 cm between each of them

– a plurality of inflatable lateral arms attached to the body of tree central arm 64.

These arms are perpendicular to the body of the central arm when they are in an expanded position and the distance between the tip of these arms and die catheter shaft is precisely determined by the pressure applied. There are two electrodes 62 provided in the tip portion of the lateral arms with a precise distance between the proximal electrode and the catheter shaft. In this way, the arms would have a negligible size when in a retracted position allowing the main body to be easily manipulated and when the arms are expanded we can see die parallel recordings between the different arms enabling us to determine the direction of die depolarization in the same way as the experiments of Smeet & al, or use the different electrodes in the same manner as described above to determine the velocity in different directions.

FIG. 26 shows another embodiment in which the head portion includes:

-tree arms 69,71 longitudinally spaced-apart having an interconnected proximal extremity.

The distal extremity of the arms are connected to a very expandable, cylindrical, thin balloon (expanding system) allowing the physician to extend the arms more and more by increasing the pressure in this balloon.

-a plurality of electrodes connected to a console by a plurality of insulate leads 79 threaded in die catheter shaft are provided in each arm allowing an extremely precise mapping in each position.

-a stabilizing system which is a ring-like, thin very expandable balloon connected to an inflation lumen 80 by an inflation port 77. Its function is identical to the stabilizing 15 systems described above.

By increasing the movement of the expanding system, the lateral arms are progressively extended.

In this way, the arms take the place of the radius of the circle which has as its center, the proximal end of the arms.

This allows the measurement of the conduction velocity in all directions, because if the stimulation comes from the central electrodes 73 and the measurement of the conduction velocity between the median 72 and distal 74, and distal 74, electrodes, it’s possible to measure between 0 and 180 and it the opposite direction between 180 and 360.

Each lateral arm is further linked to a cylindrical, very rigid balloon 70 which is coupled to an inflation port 77 through an inflation lumen 80 extending along the length of the catheter shaft 75.

This balloon is inflatable with fluid, preferably radiopaque solution, which is inject by a syringe at balloon inflation port 77.

By increasing the volume of the balloon progressively the arms become very rigid and keep a straight position.

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. page 12 and 13

ENDOCARDIAL CATHETER SYSTEM FOR WAVELENGTH MEASUREMENT, MAPPING AND ABLATION

Claims of WO0025685 (A1)

 

A high quality text as facsimile in your desired language may be available amongst the following members:

CA2348558(A1)    DE69835838 (T2)    EP1123046(B1)

.original claims

.claims three

The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

What is claimed: 1) An ablation catheter system for introduction into an atrial chamber of a heart and creation of linear lesions comprising:

– a flexible elongated tubular member having proximal and distal extremities. The said flexible elongated member having a plurality of lumens therein, extending through the distal extremity of the flexible elongate member and opening either in the distal ablation part or in the stabilizing system. One of these is a large lumen in which an ablating catheter can slide.

– a  flexible distal working catheter area (working head) in continuity with the flexible elongated tubular member and having one large lumen in continuity with the lumen of the elongated member and a plurality of electrodes spaced-apart longitudinally thereon for linear ablation or other electrical functions.

-a special catheter having ablating electrodes on its distal extremity is slid ably mounted in one of the said lumens, electrical conductors extending from the proximal extremity to the electrodes are provided.

-a stabilizing system which is a hollow, ring-like member bonded to the head portion having expanded and contracted positions. When expanded the stabilizing system applies the distal extremity of the flexible elongated member and the electrodes carried thereby against the wall of the atrium.

In one embodiment the said stabilizing system is made of a ring-like balloon of a very compliant material and is constructed to permit the user to select the dimension of the ring-like structure when inflated by selecting the volume of inflation fluid which is introduced. After the stabilization of the head portion the physician applies radiofrequency energy to all of the electrodes by the special catheter, one by one, or in gang.

2) an ablation catheter system for introduction into an atrial chamber of a heart and creation of liner lesions comprising:

-a flexible, elongated, tubular member having proximal and distal extremities, a plurality of lumens and electrical conductors extending along the longitudinal axis between the proximal and distal extremities. There is a central lumen in which a metallic guide member can be threaded.

-a flexible distal working catheter area (working head), having a plurality of longitudinally spaced-apart electrodes. Electrical means extending through the elongated tubular member and connected to the electrodes for performing electrical function.

-a stabilizing system including a ring-form balloon, made of a very compliant material connected to a screw syringe by an inflation lumen extending from the proximal extremity to the distal extremity of the elongated tubular member.

3) The catheter of claim I in which there are two lateral arms provided in each side, each having a contracted and an expanded position. In the distal extremity of the said arms there are pairs of electrodes having equal distances from the catheter shaft which are connected by conducting

Means threaded along these arms and the catheter shaft, and are connected to a console for measurements. In an extended position these arms have an equal distance from the catheter shaft and are perpendicular to it so if the recordings are parallel one can confirm the direction of the conduction velocity. In one embodiment the said arms are constructed by thin cylindrical balloons having a high strength and a very low elasticity.

The measurement of the wavelength and the ablation is possible by the same catheter.

4)A catheter system as in claim 1 and 3 wherein the head portion includes two lumens in the catheter shaft by one of which the cooling solution is introduced to the head portion and by the other one it is drained .

5) An ablation catheter system for introduction into an atrial chamber of a heart and creation of liner lesions comprising:

-an elongated, flexible catheter shaft having a plurality of lumens, one of which is large and wherein an ablation catheter can slidaby move, the others being inflation lumens.

– an ablation head (working head) comprising a catheter shaft in continuity with the catheter shaft which has a slotted opening. The electrodes of the ablation catheter will be applied to the atrial wall by this opening.

-a stabilizing system which is a ting-form, thin, very expandable balloon connected to a screw syringe by an inflation lumen and attached to the working head in the opposite side of the slotted opening. In the expanded position the stabilizing system applies the working head to the atrial wall in a manner that the slotted opening is applied to the atrial wall.

6) an ablation catheter system as in claim 5, wherein the source of energy comprises a source of radiofrequency electrical energy.

7) an ablation catheter system ad in clam 5, wherein the source of energy comprises a source of laser energy.

8) an ablation catheter system ad in clam 5, wherein the source of energy comprises a source of microwave energy.

9) a wavelength measuring catheter system for introduction into an atrial chamber of a heart and the measurement of the conduction velocity and the anisotropy of the conduction comprising:

-an elongated, flexible, catheter shaft having a proximal and a distal extremity with a plurality of inflation lumens and insulated conductors extending from the proximal extremity to the distal extremity.

– a flexible distal working catheter area (working head) including: three longitudinally extending spaced-apart arms having an interconnected proximal extremity. There are a plurality of electrodes provided on each arm which are connected by a plurality of conductors threaded in the arms and the elongate member to a console. The working head undergoes a contracted position and an expanded position. The expanded position is secured by a plurality of cylindrical thin balloons of approximately one mm diameter made of a very strong, non-stretchable resinous material extended between the arms and connected to screw syringes by inflation lumens threaded in the central branch and the elongated member. These balloons are inflated by radiopaque solutions and assure a parallel position to the branches in which the inter-electrodes distances are predetermined allowing the measurement of the conduction velocity in several directions.

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