Multi-electrode balloon catheter with circumferential and point electrodes

The present invention relates to electrophysiological (EP) catheters, specifically EP catheters for cardiac mapping and / or ablation.

Cardiac arrhythmias and especially atrial fibrillation remain a common and dangerous condition, especially in the elderly population. In patients with normal sinus rhythm, the heart, including the atrium, ventricles and excitatory conduction tissue, is electrically excited and beats in a synchronous, patterned manner. In patients with cardiac arrhythmias, the abnormal areas of cardiac tissue do not follow a synchronous pulsatile cycle by the normally conductive tissue of patients with sinus rhythm. On the other hand, in the abnormal region of the cardiac tissue, the conduction to the adjacent tissue is abnormal, which disturbs the cardiac cycle and causes an asynchronous cardiac rhythm. Such abnormal conduction occurs in various areas of the heart, such as the area of the atrioventricular (AV) node and the sinoatrial (SA) node along the conduction path of the His bundle, or the myocardial tissue that forms the walls of the ventricles and atrium. It has been known so far.

Cardiac arrhythmias, including atrial arrhythmias, can be of the multi-wavelet reentrant type, characterized by multiple asynchronous loops of electrical impulses that are scattered around the atrium and often self-proliferate. Instead of or in addition to the multi-wavelet reentrant form, cardiac arrhythmias also have a local origin, such as when a limited area of atrial tissue is autonomously excited in a rapid and repetitive manner. May have.

Many clinical manifestations result from irregular cardiac function and the consequent hemodynamic abnormalities associated with atrial fibrillation, including stroke, heart failure, and other thromboembolism. In fact, atrial fibrillation is a major cause of stroke, and hemodynamic abnormalities caused in the left atrium by fibrillation wall movement are thought to induce thrombus formation in the atrium. Thromboembolism eventually travels into the left ventricle, where it sends the embolus into the cerebral circulation, where it causes a stroke. Therefore, many techniques have been developed to treat atrial arrhythmias, including pharmacological, surgical and catheter ablation.

Examples of catheter-based devices and treatment methods generally target the perimeter of the atriosphere, the disclosure of which is incorporated herein by reference, U.S. Pat. No. 5,617,854 (Munsif), U.S. Pat. No. 4,898,591. Straight or curved to the atrial demarcation wall tissue, as disclosed in Jang et al., US Pat. No. 5,487,385 (Avitall) and US Pat. No. 5,582,609 (Swanson). It has been performed by a cauterizing catheter device adapted to form a shaped, cauterized or the like treated site and methods using it. US Pat. Nos. 5,427,119, 5,497,119, the disclosure of which is incorporated herein by reference, to use a special guide sheath design for use in ablation of the right atrium and / or the left atrium. No. 5,564,440, and No. 5,575,766 (all of which are disclosed by Swartz et al.).

Minimally invasive percutaneous catheter ablation, which uses the design of an end electrode catheter for the purpose of ablation and treatment of localized arrhythmias in the pulmonary veins, has been disclosed. These ablation procedures are usually characterized by the application of electrical energy to the tissue in small increments to form localized ablation sites to block inappropriate conduction pathways. Localized ablation aims to destroy and treat localized arrhythmias caused by the pulmonary veins.

U.S. Pat. No. 6,973,339 discloses Lasso catheters for pulmonary vein mapping and ablation. An instrument that maps the pulmonary veins (PV) in an annular shape preferably comprises a catheter that includes a bend of a certain known length, roughly along the shape of the inner surface of the PV. The bend comprises one or more detection electrodes, the proximal end of which is joined to the base of the catheter at a constant angle, at a generally known angle, or at an angle with a limited range thereof. .. Preferably, at least one single coil 5D position sensor is secured to the bend of the catheter. Most preferably, two single-coil 5D position sensors are fixed to the bend, one at the distal end and one approximately in the center of the bend. The multi-coil 6-dimensional position sensor is preferably fixed at the distal end of the base, near the junction with the bend. A catheter is inserted into the heart and the bend is placed in contact with the PV wall essentially continuously, while the base is placed inside the left atrium, typically with the bend. The junction of the veins is arranged so that it is located at the heart of the vein. The information generated by the three position sensors can be used to calculate the position and orientation of the detection electrodes, allowing mapping of the PV surface.

U.S. Pat. Nos. 6,024,740 and 6,117,101 disclose an annular ablation device assembly adapted to form an annular conductive block in the pulmonary vein. The assembly is adapted to cauter the annular region of tissue along the pulmonary vein wall that surrounds the pulmonary vein cavity, thereby cutting off electrical conduction along the longitudinal direction of the pulmonary vein toward the left atrium. Includes ablation element. The annular ablation element includes an inflatable member having a working portion that is adjustable from a radially folded position to a radially expanded position. The equatorial zone surrounds the outer surface of the work area and is adapted to cauterize the tissue adjacent to the equatorial zone when actuated by a cauterizing actuator. When the width of the equatorial zone along the longitudinal direction of the inflatable member is narrower than that of the working portion, and the length along the circumferential direction is also in the position where the working portion is expanded in the radial direction. Substantially shorter than the length in the same direction. A heat insulating member arranged in a certain pattern and covering the cauterizing element may be included. Without such insulation, the cauterizing element would form the aforementioned equatorial zone over the entire working area. The inflatable member is adapted to follow the shape of the region of the hilar portion of the pulmonary vein. It is achieved by providing a considerable degree of radial adaptability or by providing a tapered shape along the work area such that its outer diameter decreases toward the distal direction. .. There is a composite assembly in which a linear ablation element is provided adjacent to the annular ablation element. Such composite assemblies are suitable for use in minimally invasive "maze" type surgery (Maze procedure) in the pulmonary vein region near the ventricle of the left ventricle.

In addition, various energy delivery therapies for forming cauterized sites in the atrial wall have been disclosed so far. Such treatments include those that use microwaves, lasers, and more generally high frequency energy to form conductive cutoffs along the heart tissue, the disclosure of which is described herein by reference. Incorporated in WO 93/20767 (Stem et al.), U.S. Pat. No. 5,104,393 (Isner et al.), And U.S. Pat. No. 5,575,766 (Swartz et al.), Respectively. .. U.S. Pat. No. 6,558,375 (Sinofsky et al.) Discloses a hand-held method for irradiating cardiac ablation instruments and target ablation sites. The instrument may include at least one light transfer optical fiber and a light diffusing element to create an annular or curvilinear ablation site. The light passing through the optical fiber for light transmission is scattered in a circular pattern by the light diffusing element. The light diffusing element may include a scattering medium, a reflective end cap, and a reflective surface that is radially opposed to the target ablation site. These components interact to provide a substantially uniform laser irradiation over the ring-shaped target area.

Cauterization with a freezing bath is also known. U.S. Pat. Nos. 7,896,870, 7,951,140, and 8,083,732 (Arless et al., Respectively) disclose catheters with a freezing ablation tip with an electrically driven ablation assembly for applying heat to tissue. There is. The freezing and cauterizing tip can be implemented by a cooling chamber in which a controlledly injected coolant circulates to reduce the temperature of the tip, and a high frequency electrode is placed at its distal end. Have. The radiofrequency electrode can be operated to warm the tissue cooled by the cryogen, or the coolant is controlled to cool the tissue to conduct electricity in cooperation with the radiofrequency treatment regimen. be able to.

It is emphasized that special care is taken to ensure that the ablation site is actually continuously connected, regardless of what type of catheter is used. Otherwise, irregular electrical activity in the pulmonary veins may continue to contribute to atrial arrhythmias. Often, whether by balloon catheter, Lasso catheter, or other method, the area where the pulmonary vein has been ablated is later checked to see if the pulmonary vein isolation was successful. Positions and points where the ablation site is not connected may be found. Isolation is usually completed using a point ablation catheter.<u style="single">For example, a balloon catheter is disclosed in Patent Document 1.</u><u style="single"> [Patent Document 1]</u><u style="single"> U.S. Pat. No. 05846238</u>

Catheter with pressure sensitive function to detect contact with tissue is known, and this type of catheter facilitates the formation of a cauterized site while avoiding puncturing the tissue. Can be done. Such a catheter may include a small transmission coil and a plurality of sensitive coils provided at opposite positions on the distal apex joined flexibly. This design is particularly suitable for point ablation catheters, but not for catheters that come into contact with tissue over a certain area or many locations. Such unsuitable catheters include those such as coil catheters or "Lasso" catheters that have a distal electrode assembly in a generally circular portion. In these types of catheters, the generally circular portion is perpendicular to the catheter body, so the generally circular portion should be checked for contact between the tissue and the electrodes in the generally circular portion. However, even if the operator applies a force toward the distal side to the catheter body, it may not be possible to apply a uniform pressure along the longitudinal direction thereof. In particular, electrodes closer to the catheter body tend to exert greater pressure on the tissue.

As described above, each type of catheter has advantages and disadvantages. Point Catheter catheters have a distal tip electrode that is more suitable for performing point cauterization, but cauterizing a large area can be time consuming and labor intensive. Circular ablation catheters achieve multiple contact points at the same time, requiring less operator skill and time, but cannot easily adapt to anatomical differences between individual patients. There is also. As a result, it may be necessary to use at least two or three catheters in a single operation to verify the success or failure of mapping, ablation, and electrical / anatomical isolation. It significantly increases the cost and time for surgery.

<p> Therefore, there is a need for electrophysiological catheters capable of providing both punctate and annular mapping and cauterization. The catheter may employ a radially inflated configuration for circular contact with tissue while having a distal tip electrode for point contact with tissue. desirable. Further, it is desirable that the catheter has an enhanced pressure sensitive function so that it can handle a two-dimensional and three-dimensional electrode assembly having a plurality of electrode contact points.</p>

<p> The present invention presents at least one adaptable balloon member and on the outer surface of said balloon member for annular detection or cauterization in a tubular region of the heart, including pulmonary veins or ventricles. The subject is a catheter comprising a balloon electrode assembly comprising at least one electrode provided in. The catheter may also include an electrode assembly with an distal end electrode and / or an annular electrode on the distal side of the balloon electrode assembly, adapted for localized contact.</p><p> The balloon electrode assembly remains contracted while the catheter travels through the patient's body towards the desired position in the heart. The balloon electrode assembly may remain contracted while cardiac mapping is being performed. The balloon electrode assembly may then be expanded to the desired perimeter / size and inserted into the pulmonary venous spiracles. The balloon electrode assembly is adapted to be present within the spiracles while keeping the electrode in contact with tissue along its outer surface. The operator of the EP catheter performs cauterization, rotation of the assembly, cauterization, etc. until almost all points along its outer surface have been cauterized to allow isolation of the pulmonary veins. Each pulmonary vein should be isolated in this way. The balloon electrode assembly is then contracted and a distal electrode assembly for localized point contact is used to verify the success or failure of the isolation. In that regard, in more complex cases, the distal electrode assembly can be used for fine punctate correction, contouring, continuous split atrial ablation, and other high frequency ablation. It may be used based on a strategy such as. The versatility of this catheter has the advantage of smoothing the workflow and reducing the number of different types of catheters used in atrial procedures, which would otherwise be greater. The balloon electrode assembly not only allows the operator to place the electrodes more confidently in the pulmonary veins, but also the distal punctate assembly using the same catheter. Can be treated.</p><p> In one embodiment, the catheter comprises an elongated catheter body, a first assembly, and a second assembly. The first assembly comprises at least one balloon member having an outer surface and at least one electrode on the outer surface, located distal to the catheter body. The second assembly has at least one electrode and is distal to the first assembly. The catheter also comprises a tube extending through the catheter body. In the catheter body, the tube defines a cavity adapted to allow fluid to pass through the at least one balloon member so as to inflate the at least one balloon member.</p><p> In a more detailed embodiment, the catheter further comprises a pressure sensitive assembly. The pressure sensitive assembly can be located proximal to the at least one balloon member or between the distal and proximal ends of the at least one balloon member.</p><p> In a more detailed embodiment, the at least one balloon member has at least one fluid port configured to allow fluid to flow from the inside to the outside of the balloon member.</p><p> In a more detailed embodiment, the catheter further comprises a second outer balloon member configured to cover at least a portion of the at least one balloon member.</p><p> In a more detailed embodiment, the at least one electrode is elongated and is located along the longitudinal axis of the catheter. The at least one electrode of the second assembly includes an irrigation tip electrode or a ring-shaped electrode.</p><p> In an alternative embodiment, the catheter comprises an elongated catheter body, a balloon electrode assembly on the distal side of the catheter body, and a tube extending through the catheter body. The balloon electrode assembly has at least an inner balloon member, an outer balloon member covering at least a portion of the inner balloon member, and at least one electrode on the outer surface of the outer balloon member. The tube defines a cavity adapted to allow fluid to pass through the inner balloon member in order to inflate the inner balloon member. The outer balloon member is adapted to expand in response to expansion of the inner balloon member.</p><p> In a more detailed embodiment, the catheter comprises a distal electrode assembly that is distal to the balloon electrode assembly.</p><p> In a more detailed embodiment, the inner balloon member is configured to allow fluid to pass from the inside of the inner balloon member to the outer space of the inner balloon member covered by the outer balloon member, at least. Has one fluid port. The outer balloon member has at least one fluid port configured to allow fluid to pass from the space to the outside of the outer balloon member.</p><p> In a more detailed embodiment, the catheter comprises a pressure sensitive assembly having an elastic member that is sensitive to the contact pressure applied to the balloon electrode assembly.</p>

These and other features and advantages of the present invention, when considered in conjunction with the accompanying drawings, will be better understood by reference to the following embodiments for carrying out the invention.<figref num="1">It is a perspective view of the catheter of this invention by one Embodiment.</figref><figref num="2">It is a side sectional view of the balloon electrode assembly and the distal tip of the catheter of FIG. 1, which is shown in a contracted / folded state.</figref><figref num="2A">FIG. 5 is a cross-sectional view of the end of the balloon electrode assembly of FIG. 2 cut along FIG. AA.</figref><figref num="2B">FIG. 2 is an end sectional view of the distal tip of FIG. 2, cut along line BB.</figref><figref num="3">FIG. 2 is a cross-sectional view of the end of the balloon electrode assembly of FIG. 2, which is shown in an inflated / expanded state.</figref><figref num="3A">FIG. 3 is a cross-sectional view of the end of the balloon electrode assembly of FIG. 3 cut along FIG. AA.</figref><figref num="4">It is a perspective view of the balloon electrode assembly of FIG. 1 and is shown in an inflated / expanded state.</figref><figref num="5">It is a perspective view of the distal electrode assembly of this invention by one Embodiment.</figref><figref num="5A">It is a side sectional view of the electrode assembly of FIG.</figref><figref num="6A">FIG. 5 is a side sectional view of a catheter having an intermediate bendable portion according to another embodiment of the present invention, cut along a first diameter.</figref><figref num="6B">FIG. 6A is a side sectional view of the catheter of FIG. 6A, cut along a second diameter approximately perpendicular to the first diameter.</figref><figref num="6C">It is a cross-sectional view of the end face cut along the line CC of the intermediate bendable part of FIGS. 6A and 6B.</figref><figref num="7">FIG. 3 is a perspective view of the distal electrode assembly of the present invention according to another embodiment.</figref><figref num="7A">FIG. 7 is a side sectional view of the distal electrode assembly of FIG.</figref><figref num="8">FIG. 3 is a perspective view of a half-expanded / inflated balloon electrode assembly of the present invention according to another embodiment.</figref><figref num="8A">FIG. 5 is a cross-sectional view of the end of the balloon electrode assembly of FIG. 8 cut along FIG. AA.</figref><figref num="9">It is a perspective view of the balloon electrode assembly of this invention by another embodiment.</figref><figref num="9A">9 is an end sectional view of an embodiment of an intermediate bendable portion suitable for use with the balloon electrode assembly of FIG.</figref><figref num="10">FIG. 5 is a side sectional view of a catheter cut along a first diameter according to another embodiment of the present invention.</figref><figref num="10A">It is sectional drawing of the end part cut along the line AA of the intermediate bendable part of FIG.</figref><figref num="10B">It is an end sectional view of the balloon member of the intermediate bendable part which has a spacer according to another embodiment of this invention.</figref><figref num="11">FIG. 5 is a side sectional view of a catheter portion accommodating a pressure sensitive assembly according to one aspect of the present invention.</figref>

With reference to FIG. 1, the present invention can be dilated and contracted as required to map and / or cauterize the tubular region of the heart, including the pulmonary veins around the left atrium. The target is a catheter 10 having a flexible balloon electrode assembly 25.

The catheter 10 comprises an elongated catheter body 12, a control handle 16 located at the proximal end of the catheter body 12, and a balloon electrode assembly 25 located at the distal end of the catheter body 12.

As shown in FIGS. 2 and 2A, the catheter body 12 has an elongated tubular structure with an outer tube 17 having one lumen 21 and an inner tube 18 having one lumen 20. , A guide wire tube 19 having a guide wire lumen 22 is provided. The tubes 17, 18, and 19 are coaxial, the inner tube 18 extends through the cavity 21 of the outer tube 17, and the guidewire tube 19 extends through the cavity 20 of the inner tube 18. There is. Tubes 17, 18, and 19 are flexible, i.e. flexible, but substantially incapable of compressing in the longitudinal direction. Any of the above tubes may have any structure as long as it has a suitable structure, and may be made of any material as long as it is a suitable material. In one embodiment, tubes 17, 18, and 19 are made of polyurethane or PEBAX® (note that PEBAX is a polyether blockamide copolymer). The outer tube 17 further comprises an implantable braided mesh, such as stainless steel, to increase the torsional stiffness of the catheter body 12, thereby causing the distal end of the catheter body 12 to rotate when the control handle 16 is rotated. , Rotate according to it.

As shown in FIG. 1, on the proximal side of the control handle 16, a connecting member or hub 4 is attached to the inner tube 18 and the guide wire tube 19. Each of the inner tube 18 and the guide wire tube 19 has a proximal portion extending proximal to the control handle. The connecting member 4 has ports 8 and 9, which are connected to the cavity 21 of the inner tube 18 and the cavity 22 of the guide wire tube 19, respectively. Port 8 is adapted to connect to a source of fluid that can apply pressure and a pump (not shown). Port 9 is adapted to receive a guide wire (not shown).

The outer diameter of the catheter body 12 is not important. In one embodiment, the outer diameter is about 8 French or less, more preferably 7 French or less. Similarly, the thickness of each tube is not important, as long as each lumen provides sufficient clearance between the tubes to accommodate and / or pass various parts and / or substances. As shown in FIGS. 2 and 2A, the components extending through the cavity 20 between the outer and inner tubes 18 are electromagnetically housed in or near the lead wire 30 for the electrodes and the assembly 25. Cable 28 for position sensor 32 is included. Other components may include a pair of thermocouple wires (not shown). The material flowing through the lumen 21 between the inner tube 18 and the guidewire tube 19 is an expansion medium for inflating the balloon assembly 25, such as saline.

The effective length of the catheter body 12, excluding assembly 25, inserted into the patient's body can vary widely depending on the desired situation. In one embodiment, the effective length ranges from about 110 cm to about 120 cm, more preferably from about 115 cm to about 117 cm, even more preferably from about 116 cm.

With reference to FIGS. 2 and 4, a balloon electrode assembly 25 is provided at the distal end of the catheter body 12. The balloon electrode assembly 25 includes at least a pair of generally similar shaped and sized outer and inner balloon members 24, as well as a plurality of electrodes 26 provided on the outer surface of the outer balloon member 23. The distal assembly 27 extends from the distal end of the balloon electrode assembly 25. In the illustrated embodiment, the distal assembly is housed in the outer ring or tube 28, the inner ring or tube 29, and the distal assembly between the ring 28 and the ring 29. Including 32. The cable 34 attached to the sensor 32 extends within the gap G between the inner balloon member 24 and the outer balloon member 23. The distal end of the guidewire tube 19 extends through the inner ring 29 and extends to the same position as the distal end of the inner ring 29. Adhesive 35 is applied to keep the distal assembly 27 together. The adhesive forms a non-invasive end around the distal end of the guidewire tube 19. Therefore, the distal ends of the ring 28 and / or the ring 29 are tapered.

With reference to FIGS. 2, 3 and 3A, balloon members 23 and 24, respectively, are generally tubular, with a proximal opening, a distal opening, and cavities C23 and C24 between them. Have. Since the inner balloon member 24 is slightly smaller than the outer balloon member 25, it fits inside the outer balloon member 23. However, when the inner balloon member 24 is expanded, it can be expanded by applying an outward force to the outer balloon member. In addition, in this specification, the two terms "expansion" and "expansion" are interchangeable. Similarly, "folding" and "shrinking" are interchangeable. The inner balloon member 24 is attached so as to cover the distal portion of the guide wire tube 19 extending distally from the catheter body 12. That is, the inner balloon member 24 extends through the cavity C24 between the proximal opening 24P and the distal opening 24D of the member 24, distal to the guidewire tube 19. It surrounds the part. The proximal opening 24P is fitted and sealed around the outer surface of the distal end of the inner tube 18. The distal opening 24D is fitted and sealed around the outer surface of the proximal end of the inner ring 29 of the distal assembly 27.

The outer balloon member 23 is mounted so as to cover the inner balloon member 24 so that the inner balloon member 24 is surrounded and exists inside the outer balloon 23. The proximal opening 23P is fitted and sealed around the outer surface of the distal end of the outer tube 17. The distal opening 23D is fitted and sealed around the outer surface of the proximal end of the outer ring 28 of the distal assembly 27.

With reference to FIG. 4, the electrodes 26 are radially arranged around the outer balloon member so as to form at least one circumferential row. Each electrode is aligned with adjacent electrodes in the same row at equal distances. In the illustrated embodiment, the electrodes are arranged in two or more rows in a circumferential shape on the approximately distal half of the outer balloon member 23. However, in the adjacent rows R1 and R2, they are radially offset or staggered from each other. In one embodiment, row R2 has nine electrodes and row R1 has at least nine electrodes, but more preferably three or four electrodes.

Each electrode is attached to, vapor-deposited, or otherwise attached to the outer surface of the outer balloon member 23 and corresponds to a corresponding lead through a small hole or opening in the side wall of the member 23. Connected to wire 30. Each lead wire 30 extends distally from the catheter body 12 towards each electrode through the gap G between the outer balloon member 23 and the inner balloon member 24.

Balloon members 23 and 24 are made of a flexible and adaptable material. Such materials may be elastic or inelastic, but members 23 and 24 may expand or expand outward due to internal forces (see Figure 2). It is a material that enables the members 23 and 24 to be contracted or folded (see Fig. 3) when such force is not applied or when the force applied so far is released. It is a material that becomes. Such inner force is provided by introducing an expansion medium into the cavity C24 of the inner balloon member 24. Port 8 (see Figure 1) is connected to a source and pump (not shown) of a fluid or expansion medium that can be pressurized, which pumps the expansion medium into port 8 and into the cavity of the inner tube 18. Through 21, deliver to the space between the inner tube 18 and the guide wire tube 19. The relative size of each of the inner tube 18 and the guide wire tube 19 is determined so that the expansion medium can flow over the entire length of the catheter sufficiently and unimpeded. The expansion medium passes through the catheter body 12 and enters the cavity C23 of the inner balloon member 23 to inflate the balloon member. The inflated inner balloon member 23 then inflates the outer balloon member 24. In order to contract the balloon members 23 and 24, the expansion medium can also be withdrawn from the cavity C23 through the cavity 21 by reversing the pump.

5 and 5A show the distal assembly 227 according to another embodiment. The distal assembly 227 has a structure similar to that of the distal assembly 27 as illustrated in FIGS. 2 and 3 and described above. However, one of the differences is that the ring-shaped electrode 248 is provided in the distal assembly 227. In the distal assembly 227, the outer ring 228 has at least one annular electrode 248 on the distal side of the balloon assembly 225. In the illustrated embodiment, the outer ring 228 is provided with two ring-shaped electrodes, each connected to a corresponding lead wire 230. The lead wire 230 extends between the outer ring 228 and the inner ring 229 and, more proximally, between the inner balloon member 223 and the outer balloon member 224. The inner ring 229 may be lengthened to help support the distal assembly 227. The position sensor 232 and its cable 234 are located between the rings 228 and 229.

As shown in FIGS. 6A and 6B, the catheter body 112 of another embodiment has an elongated tubular structure with a single lumen 115 near the axis or in the center. The catheter body 112 is flexible, i.e. flexible, but substantially incompressible along its longitudinal direction. The catheter body 112 has any suitable structure and can be made of any suitable material. One possible structure is made of polyurethane or PEBAX® (note that PEBAX is a polyether blockamide copolymer). The catheter body 112 has an outer wall 117, which is provided with an implantable braided mesh made of stainless steel or the like to increase the torsional rigidity of the catheter body 112. Therefore, when the control handle (not shown) is rotated, the distal end of the catheter body 112 rotates accordingly.

The outer diameter of the catheter body 112 is not important. In one embodiment, the outer diameter is about 8 French or less, more preferably 7 French or less. Similarly, the thickness of each tube is not important as long as the central cavity 115 can accommodate various components extending through the cavity 115. If necessary, the inner surface of the outer wall is lined with reinforcing pipe 118 to improve torsional stability. An example of a catheter body structure suitable for use in connection with the present invention is described and illustrated in US Pat. No. 6,064,905, the entire disclosure of which is incorporated herein by reference.

A component extending from the control handle 116 to the central cavity 115 of the catheter body 112 includes, for example, one or more puller wires 136 for bending the intermediate portion 114, lead wires for electrodes 130, and irrigation having a cavity 137. Includes a use / expansion tube 111, a guidewire tube 119 with a cavity 122, and a cable 134 for an electromagnetic position sensor 132 housed in or near assembly 125.

6A, 6B, and 6C show the intermediate portion 114, including the shorter portion of the tube 113, according to other embodiments. The tube has a braided mesh structure and has a central lumen 121 and a plurality of off-axis lumens. Off-axis cavities include, for example, cavities 138, 139, 140, and 141. Each of the first and second lumens 138, which are radially opposed to each other, contains puller wires 136, which allow the catheter to bend in two directions. To. The lead wire 130 is housed in the third cavity 140. Further, the sensor cable 134 is housed in the fourth cavity 141. If necessary, additional cavities can be provided.

The tube 114 of the intermediate portion 113 is preferably made of a suitable non-toxic material that is slightly more flexible than the catheter body 112. A suitable material for tube 113 is braided polyurethane with an embedded mesh such as braided stainless steel. The dimensions of each lumen are not important as long as they are long enough to accommodate each component extending through these lumens.

The length of the middle portion 14 is the relatively small portion of the effective length of the catheter, from about 6.35 cm to about 7.62 cm, more preferably from about 6.43 cm to about 6.5 cm, and even more preferably about 6.4 cm. Is.

Means for attaching the catheter body 112 to the intermediate portion 114 are shown in FIGS. 6A and 6B. The proximal end of the intermediate portion 114 comprises an outer surface notch 142 that receives the inner surface of the outer wall 117 of the catheter body 112. The intermediate region 114 and the catheter body 112 are attached by an adhesive or the like.

If desired, a spacer (not shown) can be provided within the catheter body 112, between the distal end and the middle of the proximal end of the stiffening tube 118 (if actually provided). .. The spacer provides a change in flexibility at the junction between the catheter body and the intermediate region, which allows the junction to bend smoothly without folding or kinking. Catheter with such spacers is disclosed in US Pat. No. 5,964,757, which disclosure is incorporated herein by reference.

The puller wire 136 contained in the cavities 138 and 139 of the intermediate shaft 14 is preferably coated with Teflon®. The puller wire may be made of any suitable metal such as stainless steel or nitinol, or a stronger material such as Vectran® nylon tubing, and the Teflon coating imparts lubricity to the puller wire. Each puller wire may have a diameter of about 0.02 cm to about 0.03 cm (about 0.006 inch to about 0.010 inch).

As shown in FIG. 6B, each puller wire 136 passes through a compression coil 143 that surrounds each corresponding puller wire. The compression coil 143 generally extends from the proximal end of the catheter body 112 to the proximal end of the intermediate 114, the proximal and distal ends of which are the stiffening tube 118 and the tube 113, respectively. It may be fixed to the proximal end of the device by an adhesive joint (not shown). The compression coil 143 is made of any suitable metal, preferably stainless steel, and is flexible, i.e. bendable, but tightly wound around itself to resist compression. The inner diameter of the compression coil is preferably slightly larger than the diameter of the puller wire. Within the catheter body 112, the outer surface of the compression coil 143 is also coated with a flexible non-conductive sheath 144, for example made of polyimide tubing. Within the intermediate 114, each puller wire extends through a protective sheath 145 to prevent the puller wire from biting into the tube 113 of the intermediate 114 as it bends.

The proximal end of the puller wire 136 is anchored to the control handle 116. The distal end of the puller wire is anchored at or near the distal end of the middle 114 of the tube 113. As shown in FIG. 6B, a T-shaped fixture is formed. The T-fix includes a small piece of annular stainless steel 146 that fits over the distal end of the puller wire, eg, a subcutaneous crossbar, and that small piece of annular stainless steel 146 is firmly attached to the puller wire. It is fixed by caulking. The distal end of the tubular stainless steel 146 is firmly attached to a cross piece 147 formed of a stainless steel ribbon or the like, for example by welding. Cross 147 extends through a hole (not shown) formed within tube 113. Since the cross piece 147 is larger than the hole, it will not be pulled out of the hole, and the cross piece 147 anchors the distal end of the puller wire to the distal end of the intermediate 114.

Extending through the central lumen 121 of the tube 113 of the intermediate portion 114 is an irrigation / dilation tube 111 having a lumen 137. The guide wire tube 119 is inside the lumen 137 of the tube 111 and extends through it. The proximal ends of each of the tubes 111 and 119 are connected to a connecting member having a port similar to that shown in FIG. One port is adapted for connection with sources and pumps (not shown) of irrigation / expansion media that can apply pressure. Other ports are adapted to receive guide wires (not shown).

A balloon electrode assembly 125 is located at the distal end of the intermediate 114. As described above, the balloon electrode assembly 125 has a structure similar to that of the balloon electrode assembly 25 described above. The balloon electrode assembly 125 includes a plurality of electrodes mounted on the outer surface of the outer balloon member 123, the inner balloon member 124, and the outer balloon member 123. However, a tube 113 with multiple lumens in the middle 114 extends from the catheter body 112 to the assembly 125, and the proximal opening 124P of the inner balloon member 124 is in the central lumen 121 of the tube 113. It is inserted into the distal end and sealed to the inner surface of the central lumen 121. The proximal opening 123P of the outer balloon member 123 is fitted and sealed around the outer surface of the distal end of the tube 113.

A guidewire tube 119 extends through the lumen of the irrigation / expansion tube 111, the central lumen 121 of the tube 113 of the intermediate 114, and the cavity C124 of the inner balloon member 124. The relative sizes of the tubes 119 and 111, respectively, are balloon electrodes that pass through the lumen 137 of the tube 111 over the entire length of the catheter, with sufficient irrigation and / or expansion medium unimpeded. Determined to be able to flow up to assembly 125. As mentioned above, the balloon members 123 and 124 are made of a flexible and adaptable material. Such a material, which may be elastic or inelastic, is a material that allows both members to expand and contract. Internal force can be provided by introducing the expansion medium into the cavity C124 of the inner balloon 124.

Figures 10, 10A, and 10B show intermediate 414 and balloon assembly 425 according to other embodiments. The catheter body 412 has a tube 413 with multiple lumens, similar in structure to the tube 113 shown in FIGS. 6A and 6B. Tube 413 has one or more additional cavities. For example, off-axis cavities 457 for transporting irrigation fluid along the intermediate portion 414, which are radially opposed to each other, are provided. The irrigation solution is provided in each lumen 457 at the proximal end of tubing 413 by a corresponding irrigation tube (not shown) extending through a catheter body (not shown) connected to intermediate 114. Will be sent to. At the distal end of tube 425, each cavity 457 communicates with the space S between the outer balloon member 423 and the inner balloon member 424. An irrigation solution port 456 is formed in the outer balloon member 424. The port 456 allows the irrigation solution that has entered the space S to exit the outer balloon member 423.

FIG. 10B shows one or more spacers 455 disposed between the inner surface of the outer balloon member 423 and the outer surface of the inner balloon member 424. The spacer can be attached to the inner surface of the outer balloon member and / or the outer surface of the inner balloon member. The spacer 455 is adapted to provide a space or channel as a flow path for the fluid between the inner and outer balloon members, thereby providing a fluid between the inner and outer balloon members. Can be distributed so that fluid is not dammed or impeded in any particular area, even in situations where both balloon members are pressed against each other. ing. The spacer can have any suitable outer shape or configuration, or can have any suitable cross-sectional shape or configuration. The spacer is often in a block shape or an elongated shape (a shape extending in the longitudinal direction). In the illustrated example, the spacer has a trapezoidal cross-sectional shape, with its longer base in contact with the outer surface of the inner balloon member 424 and its shorter base in contact with the inner surface of the outer balloon member 425. By doing so, a large space as a fluid flow path can be secured between both balloon members 423 and 424 when inflated and / or pressed against the tissue. Grooves may be formed on either or both of the inner surface of the outer balloon member and the outer surface of the inner balloon member to ensure fluid distribution.

According to one feature of the invention, its flow path through the irrigation solution and the entire catheter is isolated from its flow path through the expansion medium and the entire catheter. In the latter respect, the expansion medium is delivered to the medial balloon member 424 via a structure similar to that described for the catheters of FIGS. 6A, 6B, and 6C. In the illustrated embodiment, the expansion medium tube 411 extends through the catheter body and continues to extend through the lumen 421 within the tube 413 leading into the cavity of the inner balloon member 424.

7 and 7A show the distal assembly 127'with the irrigation tip electrode 155 according to another embodiment. The distal assembly may be used with a catheter in which the irrigation tube 111 is generally replaced by the guidewire tube 19 of FIG. 2 or the guidewire tube 119 of FIG. 6A. The tip electrode 155 has a two-piece structure including a conductive dome-shaped shell 151 and a conductive plug member 152. The dome-shaped shell 151 and the plug member 152 define a cavity of the internal plenum chamber 153 surrounded and closed by the shell 151 and the plug member 152. The shell 151 has a dome-shaped, non-invasive distal end adapted for contact with tissue and an open proximal end, usually sealed with a plug member 152. A plurality of fluid ports 156 are formed on the side wall of the shell to allow fluid to communicate between the chamber 153 and the outside of the shell 151.

The plug member 152 is formed with a through hole 154 into which the distal end of the irrigation tube 111 enters. The tube 111 then provides a fluid, such as saline, which passes through the catheter body, the intermediate, if any, and the balloon assembly, flows into the tip electrode 155, and cools the tip electrode. To do. In this embodiment, the fluid passing through the tube 111 travels separately from the cavity 21 of the inner tube 18 shown in FIG. 2 or the expansion medium passing through the cavity 137 of the tube 111 shown in FIG. 6A. To do.

With reference to FIG. 4, the electrode 26 provided in any one of the balloon assemblies described herein has a generally rectangular, convex shape and a cross-sectional shape raised from the outer surface of the balloon member. The electrodes may have any suitable shape, including those in which elongated electrodes are arranged so that their longitudinal directions coincide with the longitudinal direction of the assembly, as shown in FIGS. 8 and 8A. In that regard, the inner balloon member 224 and the outer balloon member 223 may have longitudinal folds or folds 260 extending between the elongated electrode bands 226. In doing so, when the balloon member is folded, it can be facilitated to be realized in a more foreseeable and orderly manner. Each electrode band extends longitudinally or along the axial direction in the distal half region of assembly 225. The folds 260 and the electrode band 226 are provided apart from each other so as not to interfere with the structure or function of the other.

Each balloon electrode or electrode band, as well as a ring-shaped electrode and / or a distal tip electrode, is connected to an energy source for cauterization by a corresponding lead wire. The ablation energy source is adapted to selectively deliver energy to the electrodes as needed or desired.

9 and 9A show an embodiment of an irrigation balloon electrode assembly 325 with electrodes 326 provided on a single or outer balloon member 323. The proximal opening 323P of member 324 is attached to the distal end of tube 313, which has multiple lumens in the intermediate bendable portion 314. In the disclosed embodiments, the tube 313 has a central lumen 321 and four off-axis lumens 338, 339, 340, and 341. A lead wire 330 to any other electrode of the balloon electrode 326 and the distal electrode assembly 325 also extends through the central cavity 321. The puller wire 336 for bidirectional bending extends through the cavities 338 and 339. Both the dilator and the irrigation fluid flow through one or both of the cavities 340 and 341.

The side wall of the balloon member 323 can be provided with many small holes or an irrigation port 372 can be formed. When the fluid flows into the cavity of the balloon member 323, the balloon member expands and the fluid exits the balloon member through the irrigation port 372 to cool the balloon electrode 326. Port 372 is generally located very close to electrode 326. It should be noted that any ring-shaped electrode and / or distal tip electrode may be adapted to allow fluid to flow into the distal tip assembly to cool.

A protective support tube 319 is provided between the intermediate bendable portion 314 and the distal electrode assembly 327. The tube extends through the cavity of the balloon member. Its proximal end is within the central canal 321. An opening 373 is provided on the side wall of the tube 319, through which the lead wire exits the inside of the tube 319 to the respective corresponding electrode 326. The opening may be sealed with an adhesive or sealant to prevent fluid from leaking out of the cavity into the lumen of tube 319. In that regard, the distal openings of the lumens 338 and 339 containing the puller wires are also sealed with an adhesive or sealant to prevent fluid from flowing into these lumens.

The present invention also includes a catheter that employs a pressure sensitive function in the distal portion. FIG. 11 shows an embodiment of a partial section 500 of a catheter representing a catheter body or a bendable intermediate portion proximal to the balloon electrode assembly. The catheter section 500 has many structural similarities to the catheter body and intermediates described above, as shown in FIGS. 4A, 4B, 6A, and 6B. Whether the section 500 includes a plurality of coaxial tubes or a tube 513 having a plurality of lumens, the section 500 has a central portion of a central tube or tube 519 that defines a central on-axis lumen. The lumen accommodates the pressure sensitive assembly 560 at or near the distal end of tube 519. As shown in FIG. 11, the pressure sensitive assembly 560 is generally incorporated into the junction 562 between the distal 519D and the proximal 519P. The junction 562 is similar in shape to the tube 519 and is provided by a short section of the flexible tube 561 having at least one lumen connected to the on-axis lumen of the tube 519. It is formed. Other cavities or passages may be provided that correspond to the other cavities or passages of the tube 519 and are arranged coaxially. The tube 561 should be made of a material that does not prevent the joint from bending or compressing. The tube 513 is harder and harder to bend than the tube 561.

The joint 562 includes an elastic member 563. The elastic member 563 may take the form of, for example, a coil spring, but instead other types of elastic components may be used for this purpose. The elastic member 563 responds to the force applied to the balloon electrode assembly, such as the force applied when it comes into contact with the tissue, between the balloon electrode assembly 525 and the intermediate portion 514. Allows a limited range of relative movements.

On the distal side of the elastic member 563, a magnetic position sensor 564 is housed in the lumen of tube 519 (preferably in the middle 514, the central on-axis lumen). The sensor 564 may include one or more small coils and typically includes a plurality of coils oriented along various axes. On the proximal side of the elastic member 563, a small magnetic magnetic field generator 565 is housed in the lumen of tube 519. Typically, the magnetic field generator 565 comprises a coil that is driven by an electric current delivered through the catheter. Alternatively, the position sensor 564 may include either another type of magnetic sensor, an electrode acting as a position converter, or another type of position converter, such as an impedance-based sensor or an ultrasonic position sensor. Although a single position sensor 564 is shown in FIG. 11, two or more position sensors may be used in embodiments of the present invention.

As will be appreciated by those skilled in the art, the magnetic field produced by the magnetic field generator 565 causes the coil of the sensor 564 to generate an electrical signal of the drive frequency of the magnetic field generator 565. The amplitude of these signals varies with the position and orientation of at least the distal 519D of the longitudinal tube 519 relative to the intermediate 14 extending through the balloon electrode assembly 525. A calibration processor (not shown) of the calibration unit (Fuji) processes these signals to determine the displacement and magnitude of the flexion angle of the axially distal 519D with respect to the proximal 519P. (Because the magnetic field generated by the coils is axisymmetric, only the magnitude of bending can be detected using a single coil in the magnetic field generator 565 and the direction of bending can be detected. Optically, the magnetic field generator 565 can include two or more coils, in which case the direction of bending can also be determined. In that regard, the embodiment of FIG. 11 , 3 coils are provided.) The magnitudes of displacement and flexion can be combined by adding the respective vectors to obtain the total magnitude of the movement of the distal 519D relative to the proximal 519P. ..

The relative movement of the distal 519D with respect to the distal end 14 provides a measure of the degree of deformation of the elastic member 563. Then, the magnetic field generator 565 and the sensor 564 are combined to detect the pressure. By sensing the combination of displacement and flexion, the pressure sensitive assembly 560 can apply pressure to the distal 519D or balloon electrode assembly regardless of whether it is applied head-on or diagonally. Should indicate correctly. Further details regarding the position sensor are described in US Pat. Nos. 8,357,152 and 8,535,308, the entire contents of which are incorporated herein by reference.

The catheter also includes non-volatile memory such as electrically erasable programmable read-only storage (EEPROM). The memory stores the calculated coefficients calculated at the time of calibration, as described in US Pat. No. 8,521,462, the entire disclosure of which is incorporated herein by reference. When the catheter is later used in a medical system, the actual pressure exerted by the catheter's balloon electrode assembly on body tissue is measured using the calibration-obtained coefficient stored in this memory. It can be derived with high accuracy from the bending value. If the catheter has a distal electrode assembly that is distal to the balloon electrode assembly, the pressure sensitive assembly is adapted to sense the actual pressure that the distal assembly exerts on the tissues of the body. ..

Note that the pressure sensitive assembly 560 may be placed in a variety of different positions along the distal 519D, including the portion extending between the distal and proximal ends of the balloon electrode assembly. .. When the balloon electrode assembly is pressed against the tissue surface, the various different positions described above change the stability of the balloon electrode assembly.

As is generally known in the art, an electrophysiologist may introduce a guide sheath and dilator into the patient's body to use the catheter of the invention. In addition, a guide wire may be introduced into a catheter suitable for the above-mentioned usage, such as the catheter shown in FIGS. 2 and 5. Suitable guide sheaths for use in connection with the catheters of the invention are braided guide sheaths (commercially available from Biosense Webster, Inc., Diamond Bar, Calif.), PREFACE . Is. If a guide wire is used, the guide wire is inserted and the dilator is removed. The catheter is then introduced through the guide sheath. The catheter may be introduced into the right atrium via the inferior vena cava. To reach the left atrium, the catheter passes through the septum.

The guide sheath covers the balloon electrode assembly in the folded position so that the entire catheter is passed through the patient's vascular system to reach the desired position. The adaptable material of the balloon member makes it easy for the assembly to contract and / or fold snugly within the guiding sheath. When the distal end of the catheter reaches the desired location, eg, the left atrium, the guide sheath is pulled out, exposing the balloon electrode assembly. Subsequently, the balloon electrode assembly may be inflated by introducing the expanding liquid into the balloon member. The balloon electrode assembly expands as needed or desired to fit snugly into the concave region of the ostium or atrium. To achieve circular mapping and / or cauterization, (1) extend the balloon electrode assembly, (2) one or more electrodes in the balloon electrode assembly, and one atrial tissue. Place the balloon electrode assembly in the desired position, nested, or otherwise so that it contacts along the circumference, and (3) one or more for sensing and / or cauterization. Activate the electrodes, (4) Rotate the balloon electrode assembly around its longitudinal axis so that different tissues of the atria make contact with one or more electrodes of the balloon electrode assembly approximately along the same circumference. 5) Activate one or more electrodes for sensing and / or cauterization, repeat steps (4) and (5) as desired, and (7) contract the balloon electrode assembly. (8) Activate one or more electrodes on the distal electrode assembly for sensing and / or cauterization.

The above steps or actions may be executed in the order as described above, and may be executed in an order other than the above if necessary or appropriate. Any one or more of the above steps may be performed for mapping, cauterization, and / or verification.

By known methods, such as measuring impedance, temperature, and / or contact force, the electrophysiologist can determine which electrode is in contact with the tissue of the atrium. A single, efficient, low-complexity platform with a fully integrated multi-electrode platform, such as Biosense Webster's nMARQ generator, which can operate multiple selected electrodes simultaneously. Mapping, cauterization, and verification can be performed using catheters.

As will be appreciated by those skilled in the art, the balloon electrode assembly can be fully or partially expanded. Since it can be flexed in both directions, the catheter is operated to place the balloon electrode assembly and the distal electrode assembly in or near the pulmonary vein, in the pulmonary vein, or near the pulmonary vein. can do. The electrodes on the assembly can be used in combination with a position sensor to allow the electrophysiologist to map, cauterize, and verify local uptime, which the electrophysiologist diagnoses and treats. It can be a guide in providing the law to the patient. Therefore, the electrophysiologist can visualize each electrode on one 3D mapping system. Therefore, the electrophysiologist can know where in the patient's body each electrode is when the balloon member is expanded. Each electrode may include a temperature feedback system, such as a thermistor or thermocouple.

The above description is based on a preferred embodiment of the present invention. Those skilled in the art will appreciate that it is possible to carry out the structural modifications and modifications described without significant deviations from the principles, intent and scope of the invention. As will be appreciated by those skilled in the art, drawings are not necessarily in actual size. Also, different features of different embodiments can be used in combination as needed or as long as it is appropriate. In addition, the catheters described herein can be adapted to be applied in various energy forms such as micros, lasers, radio frequencies, and / or cryogens. Therefore, the above description should not be read as relating only to the exact structure described and shown in the accompanying drawings, but rather is consistent with the following claims, which will have the most complete and fair scope. , And should be read as supporting the scope of claims.

BEST MODE FOR CARRYING OUT THE INVENTION (1) An elongated catheter body having a proximal end and a distal end, at least one balloon member having an outer surface, and at least one electrode on the outer surface. A first assembly located distal to the catheter body and adapted to extend through the catheter body and allow fluid to pass through the at least one balloon member to inflate the at least one balloon member. A catheter comprising a tube defining a defined lumen and a second assembly having at least one electrode and distal to the first assembly. (2) The catheter according to embodiment 1, further comprising a pressure sensitive assembly. (3) The catheter according to embodiment 2, wherein the pressure sensitive assembly is located proximal to the at least one balloon member. (4) The catheter according to embodiment 2, wherein the pressure sensitive assembly is located between the distal and proximal ends of the at least one balloon member. (Five) The catheter according to embodiment 1, wherein the at least one balloon member has at least one fluid port configured to allow fluid to flow from the inside to the outside of the balloon member.

(6) The catheter according to embodiment 1, further comprising a second outer balloon member configured to cover at least a portion of the at least one balloon member. (7) The catheter according to embodiment 6, wherein the at least one electrode is elongated and is located along a longitudinal axis of the catheter. (8) The catheter according to embodiment 1, wherein the at least one electrode of the second assembly comprises an irrigation tip electrode. (9) The catheter according to embodiment 1, wherein the at least one electrode of the second assembly comprises a ring-shaped electrode. (10) The catheter according to embodiment 1, wherein the fluid contains a dilator.

(11) The catheter according to embodiment 1, wherein the fluid comprises an irrigation solution. (12) An elongated catheter body having a proximal end and a distal end, at least an inner balloon member, an outer balloon member covering at least a part of the inner balloon member, and an outer surface of the outer balloon member. A balloon electrode assembly having at least one electrode, distal to the catheter body, and extending through the catheter body and into the inner balloon member to inflate the inner balloon member. A catheter comprising a tube defining a lumen adapted to allow fluid to pass through, wherein the outer balloon member is adapted to inflate in response to expansion of the inner balloon member. (13) The catheter according to embodiment 12, further comprising a distal electrode assembly on the distal side of the balloon electrode assembly. (14) At least one fluid port configured such that the inner balloon member allows fluid to pass from the inside of the inner balloon member to the space outside the inner balloon member covered by the outer balloon member. The catheter according to embodiment 12. (15) The catheter according to embodiment 14, wherein the outer balloon member has at least one fluid port configured to allow fluid to pass from the space to the outside of the outer balloon member.

(16) The catheter according to embodiment 12, further comprising a pressure sensitive assembly. (17) The catheter according to embodiment 16, wherein the pressure sensitive assembly is proximal to the balloon electrode assembly. (18) The catheter according to embodiment 16, wherein the pressure sensitive assembly is located between the distal and proximal ends of the balloon electrode assembly. (19) The catheter according to embodiment 16, wherein the pressure sensitive assembly has an elastic member. (20) The catheter according to embodiment 12, further comprising an irrigation tip electrode on the distal side of the balloon electrode assembly.