JP2014213173A - Electrode catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode catheter capable of accurately pressing an electrode section against a desired portion.SOLUTION: An electrode catheter 1 has a straight shaft 2, and a distal end side of the shaft 2 is provided with a movable section 2A that allows for curvature deformation by an operation of an operation section 3. A distal end of the movable section 2A of the shaft 2 is connected with a linear distal section 4 included in one plane including the shaft 2 in a non-deforming state. This distal section 4 has a connected area portion 4A and an electrode area portion 4B in this order from a side of the shaft 2. The electrode area portion 4B is provided in the form of crossing an extension line 2A' of the shaft 2 in the non-deforming state in an approximately-orthogonal direction. A curvature deformation direction of the movable section 2A is approximately orthogonal to the one plane.

Description

  The present invention relates to an electrode catheter suitable for, for example, mapping of an electrical activity state in the heart and measuring cardiac potential after ablation (cauterization) of the inner wall of the heart.

  The electrode catheter is used not only for the treatment of, for example, ablation of the inner wall of the heart but also for mapping the electrical activity state in the heart prior to the ablation (for example, Patent Documents 1 and 2). A plurality of electrodes for measuring cardiac potential are provided at the tip region of the shaft of such an electrode catheter. In the mapping, for example, each electrode of the catheter is placed in a peripheral region of a line (hereinafter simply referred to as a line) where occurrence of abnormal potentials such as a roof line, a bottom line, and a mitra Lewismus line in the left atrium is confirmed. Press to measure the electrocardiogram. Mapping is performed by sequentially performing this measurement, for example, along a line. Then, after identifying the location where the abnormal potential is generated by this mapping, ablation is performed along the line to block the abnormal potential.

  An electrode catheter is also used to confirm the ablation state after performing ablation treatment. Specifically, it is confirmed whether or not the abnormal potential can be blocked by pressing the electrodes of the catheter against the regions on both sides of the line after the ablation and measuring the cardiac potential.

  In such an electrode catheter, a tip region where a plurality of electrodes are arranged is configured linearly and extends in the same direction as the shaft axis (Patent Document 1), or the tip region is configured in a loop shape. (Patent Document 2) and the like.

Japanese National Patent Publication No. 10-507678 JP 2004-275767 A

  However, with the electrode catheter having such a shape, it is difficult to appropriately press the distal end region to a desired location in the heart. For example, a part of the tip region may float from the pressing surface (inner heart wall), and the entire tip region may not be pressed evenly. In particular, for the confirmation of the mapping and cauterization state, it is important to press the electrodes accurately to the areas on both sides of the line as described above. However, the practitioner needed very skill.

  The present invention has been made in view of such problems, and an object thereof is to provide an electrode catheter capable of accurately pressing an electrode to a desired location.

  The electrode catheter of the present invention includes an operation part, a linear shaft in which a proximal end is connected to the operation part, and a predetermined section portion on the distal end side is configured to be curved and deformable by operation of the operation part, A proximal distal end coupled to the distal end of the shaft and configured to be contained within a plane including the undeformed shaft, the distal portion comprising a plurality of distal portions A linear electrode region portion configured to straddle an extension line in a substantially orthogonal direction when the shaft is in a non-deformed state, a proximal end of the electrode region portion, and a distal end of the shaft And a bending deformation direction of a predetermined section portion of the shaft is a direction substantially orthogonal to the one plane.

  In the electrode catheter of the present invention, the linear electrode region portion of the distal portion is configured to straddle the extension line of the non-deformed shaft in a substantially orthogonal direction, and thus straddles the target line of the inner wall of the heart. Thus, the operation of pressing the electrode region portion is easy. In addition, since the predetermined section portion on the distal end side of the shaft can be bent and deformed in a direction (penetrating direction or crossing direction) substantially orthogonal to the one plane, there are various changes with respect to the shaft entering direction. It is easy to measure the inner wall region of the heart in any direction, and the degree of freedom of mapping is increased. For example, for the inner wall region of the heart immediately adjacent to the septal puncture for allowing the catheter to enter the left atrium from within the right atrium, mapping has hitherto been difficult. Even if it exists, a cardiac potential measurement becomes comparatively easy.

  In the electrode catheter of the present invention, it is preferable that at least one of the connection region portion and the electrode region portion is elastically deformable. When configured in this manner, the distal portion flexibly deforms in response to the heartbeat, so that problems such as separation of the electrode region portion from the inner wall of the heart during measurement can be avoided. Moreover, the electrode region portion can be softly pressed against the inner wall of the heart due to the elasticity of the distal portion.

  In the electrode catheter of the present invention, the connection region portion is positioned between the first elastically deformable portion on the shaft side, the second elastically deformable portion on the electrode region portion side, and the first portion and the second portion. The electrode region portion and the linear intermediate portion that is non-parallel are preferably configured. In this case, the elastic action of both the first part and the second part is combined to ensure sufficient elasticity for the entire distal part. In particular, since the electrode region portion and the intermediate portion are non-parallel, it is easy to increase the elastic force exerted by the second portion as compared with the case where both are parallel.

  In the electrode catheter of the present invention, the angle formed by the intermediate portion of the connecting region portion and the electrode region portion is, for example, 20 degrees to 50 degrees, and the angle formed by the intermediate portion of the connecting region portion and the non-deformed shaft is, for example, 110 degrees. It is preferable that the angle is 130 degrees.

  In the electrode catheter of the present invention, the connecting region portion is preferably curved in an S shape so as to smoothly connect the proximal end of the electrode region portion and the distal end of the shaft. In this case, since the force applied when the electrode region portion is pressed against the inner wall of the heart is distributed over the entire connection region portion, local stress concentration at both ends of the connection region portion can be suppressed.

  In the electrode catheter of the present invention, the electrode region portion is less than 90 degrees with respect to the undeformed shaft extension line so that the distal end of the electrode region portion is further from the shaft than the proximal end of the electrode region portion. It is preferable that they are provided at an angle. For example, when the angle formed by the extension line of the shaft and the electrode region portion is 90 degrees or more, when the electrode region portion is pressed against the inner wall of the heart, the distal end of the electrode region portion is simultaneously with other portions, or Since it contacts the inner wall of the heart later, the distal end tends to float. On the other hand, when configured as described above, the electrode region portion comes into contact with the inner wall of the heart sequentially from the distal end thereof, so that the distal end of the electrode region portion is less likely to lift.

  In this case, the electrode region portion is more preferably provided at 70 degrees or more with respect to the extension line of the non-deformed shaft. In this configuration, the time from the contact of the distal end of the electrode region portion to the complete pressing of the entire electrode region portion is less than 70 degrees between the shaft extension line and the electrode region portion. It becomes shorter compared with the case of.

  In the electrode catheter of the present invention, the electrode region portion can be gently bent so as to be convex on the side opposite to the shaft. When comprised in this way, it becomes possible to let an electrode area | region part follow the inner wall of a heart.

  In the electrode catheter of the present invention, the length of the electrode region portion can be made equal on both sides of the extension line of the shaft. When configured in this way, a force is easily applied evenly to the entire electrode region portion.

  According to the electrode catheter of the present invention, since the electrode region portion is provided in a direction substantially perpendicular to the extension line of the non-deformed shaft, the electrode region portion is accurately pressed against a desired location such as the inner wall of the heart. be able to. In addition, since the predetermined section on the tip side of the shaft can be curved and deformed in a direction substantially perpendicular to the plane including the non-deformed shaft, high degree of freedom and accurate operability can be realized. it can.

It is an external view showing the schematic structural example of the electrode catheter which concerns on one embodiment of this invention. It is a perspective view showing the structural example of the electrode catheter shown in FIG. It is a top view which shows some operation states of the electrode catheter shown in FIG. FIG. 3 is a perspective view showing several operating states of the electrode catheter shown in FIG. 2. FIG. 2 is a partially enlarged plan view showing a main part configuration of the electrode catheter shown in FIG. 1. It is a top view for demonstrating in detail the principal part shape of the electrode catheter shown in FIG. It is a figure showing the usage example of the electrode catheter shown in FIG. It is a schematic diagram for demonstrating the structure of the heart. It is a schematic diagram for demonstrating the pulmonary vein of the left atrium shown in FIG. It is a figure which shows the positional relationship of the electrode area | region part and the line of the heart inner wall in the use condition of the electrode catheter shown in FIG. It is a figure showing the other usage example of the electrode catheter shown in FIG. It is a wave form diagram showing an example of the time change of the cardiac potential measured with the electrode catheter shown in FIG. It is a schematic diagram showing the other usage example of the electrode catheter shown in FIG. 11 is a plan view illustrating a configuration of a main part of an electrode catheter according to Modification 1. FIG. FIG. 10 is a plan view illustrating a configuration of a main part of an electrode catheter according to Modification 2. FIG. 10 is a plan view illustrating a main configuration of an electrode catheter according to Modification 3. 10 is a plan view illustrating a configuration of a main part of an electrode catheter according to Modification 4. FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The description will be given in the following order.
1. Embodiment 2. FIG. Modification 1 (example in which the electrode region is gently curved)
3. Modification 2 (example in which the connecting portion between the shaft and the electrode region portion is an intersection of straight lines)
4). Modified example 3 (an example in which the length of the electrode region portion is different from each other on both sides of the undeformed shaft extension)
5. Modification 4 (example in which the electrode region is orthogonal to the extension line of the non-deformed shaft)

<Embodiment>
[Schematic configuration]
FIG. 1 shows a schematic configuration of an electrode catheter (electrode catheter 1) according to an embodiment of the present invention. (A) is a plan view (top surface, X direction in FIG. 1), (B) is a front view (Y direction in FIG. 1), (C) is a side view on the distal end side (Z direction in FIG. 1), ( D) shows a side view (Z direction in FIG. 1) of the proximal end side. FIG. 2 shows a perspective configuration of the electrode catheter 1.

  The electrode catheter 1 is inserted into a heart, for example, through a blood vessel, and is used for mapping the electrical activity state of the inner wall of the heart and for confirming the ablation state after ablation. The electrode catheter 1 is connected to a shaft 2 (catheter shaft) as a catheter body, an operation portion 3 provided at a proximal end (base end) of the shaft 2, and a distal end (tip end) of the shaft 2. And a distal portion 4.

(Shaft 2)
The shaft 2 extends linearly in a predetermined direction (Z direction in FIGS. 1 and 2). The predetermined section portion on the distal end side of the shaft 2 is configured as a movable portion 2A that can be curved and deformed in a direction (± Y direction) away from the shaft extending direction by operation of the operation portion 3. When the operation unit 3 is not operated (non-deformed state), the entire shaft 2 including the movable unit 2A is linear.

FIG. 3 shows a state in which the movable portion 2A is deformed in a single view and is shown in plan view, and FIG. 4 is a perspective view. In these drawings, a solid line indicates an undeformed state, and a broken line indicates a curved state.
As shown in these drawings, the movable portion 2A is substantially orthogonal to this direction from the extending direction of the shaft 2 in the non-deformed state (the -Z direction in FIGS. 1 and 2) by the operation of the operation portion 3. It is curved and deformed in the direction (± Y direction in FIGS. 1 and 2) and can be deformed up to 180 degrees (+ Z direction).

  The shaft 2 has at least one inner hole (not shown) called a lumen that extends in the main axis direction. A pair of operation wires (not shown) or the like for bending and deforming the movable portion 2A is inserted into the inner hole. The shaft 2 may be a single lumen structure having one lumen, or may be a multi-lumen structure having a plurality of lumens.

  The proximal end of the operation wire in the inner hole of the shaft 2 is connected to a rotating plate 32 (described later) provided in the operation portion 3, and the distal end is connected to the distal end of the shaft 2 (movable portion 2A). It is fixed to the anchor inside the portion 21. For example, the operation wires are arranged on both sides of an elongated leaf spring (not shown) provided along the main axis inside the movable portion 2A. The operation wire may be disposed along the inner wall of the shaft 2 or may be disposed along both surfaces of the leaf spring. The plate spring functions to prevent twisting of the movable portion 2A when the operation wire causes the movable portion 2A to bend and deform in accordance with the rotation operation of the rotary plate 32 of the operation portion 3. In order to prevent twisting of the movable portion 2A during bending deformation, a pair of highly rigid linear members, such as wires, are provided in the direction orthogonal to the pair of operation wires instead of the leaf springs. May be.

  The shaft 2 is made of a flexible material. Specifically, synthetic resin such as polyolefin, polyamide, polyether polyamide, polyurethane, nylon, and PEBAX (polyether block amide) can be used for the shaft 2. However, it is preferable to use a less rigid (flexible) material for the movable portion 2A of the shaft 2.

  The shaft 2 can be manufactured to an appropriate length (Z direction), and is, for example, about 600 mm to 1500 mm, more preferably about 900 mm to 1200 mm. The length of the movable part 2A is, for example, about 40 mm to 150 mm. The outer diameter of the shaft 2 is about 1.0 mm to 3.0 mm, more preferably about 1.6 mm to 2.7 mm.

(Operation unit 3)
The operation unit 3 (FIGS. 1 to 4) includes a handle 31 (gripping unit) and a rotating plate 32. The handle 31 is a part that the operator grips when using the electrode catheter 1. As described above, the proximal ends of the pair of operation wires provided in the inner hole of the shaft 2 are fixed to the rotary plate 32 of the operation unit 3. The rotating plate 32 is rotatable around a rotating shaft (X axis in FIGS. 1 to 4) (not shown). The rotary plate 32 is provided with rotary knobs 32A at two positions 180 degrees apart from each other. By operating the rotary knob 32A in the directions of arrows d1 and d2 (FIGS. 1 to 4) and rotating the rotary plate 32, the movable portion 2A of the shaft 2 is bent by the operation wire and the distal portion 4 is deflected. It can be made to.

(Distal part 4)
FIG. 5 is an enlarged plan view of the portion from the movable portion 2A to the distal portion 4 of the shaft 2 of FIG. The distal portion 4 is a linear member as a whole having a connection region portion 4A and an electrode region portion 4B in order from the movable portion 2A side, and is displaced and deflected following the curved deformation of the movable portion 2A. It has become. The electrode region portion 4B of the distal portion 4 is pressed against a desired location in the heart, and the cardiac potential is measured.

  The electrode region portion 4B is linear and includes a plurality of ring electrodes 41 and a tip electrode 42. The tip electrode 42 is located at the distal end of the electrode region portion 4B, and the ring-shaped electrode 41 is spaced from each other between the distal end of the electrode region portion 4B and the connecting region portion 4A, for example, about 4 to 19 pieces. Has been placed. The ring electrode 41 and the tip electrode 42 are made of, for example, a conductive metal such as aluminum, copper, stainless steel, gold, platinum, iridium, and alloys thereof. The electrode width of the ring electrode 41 is preferably about 0.5 mm to 0.7 mm. Conductive wires (not shown) are electrically connected to the ring electrode 41 and the tip electrode 42, respectively. These conducting wires extend through the lumen of the shaft 2 to the operating portion 3 while being insulated from each other.

  In the present embodiment, when the shaft 2 is in an undeformed state (in a state where the distal portion 4 is not curved and deformed), the extension line 2A ′ of the shaft 2 is substantially orthogonal (X direction in FIG. 5). An electrode region portion 4B is provided so as to straddle. The proximal end of the electrode region portion 4B and the distal end of the movable portion 2A of the shaft 2 are smoothly connected by the connecting region portion 4A.

  Thus, the shape of the distal end side section of the electrode catheter 1 has a shape similar to a mop. Here, the shaft 2 corresponds to the handle of the mop, and the electrode region portion 4B of the distal portion 4 corresponds to the wiper portion. Although details will be described later, such a shape makes it possible to accurately press the electrodes (ring-shaped electrode 41 and tip electrode 42) of the electrode region portion 4B to a desired location.

  As described above, the electrode region portion 4B is substantially orthogonal to the extension line 2A ′ of the shaft 2, but this “substantially orthogonal” is not limited to a strict orthogonal direction, and the effects of the present invention can be obtained. It is meant to include the range of angles that can be demonstrated. Specifically, the angle θ (FIG. 5) formed by the extension line 2A ′ of the shaft 2 in the non-deformed state and the electrode region portion 4B is preferably less than 90 degrees. Further, the angle θ is preferably 70 degrees or more and less than 90 degrees, more preferably 82 degrees or more and 86 degrees or less, for example, 85 degrees.

The connection region portion 4A includes a first portion 4A-1 that is a connection portion with the distal end of the shaft 2, a second portion 4A-3 that is a connection portion with the proximal end of the electrode region portion 4B, and a first portion It includes an intermediate region 4A-2 connecting between the portion 4A-1 and the second portion 4A-3, and is curved in a substantially S shape as a whole.
The first portion 4A-1 has a curved shape in which the extending direction changes in a direction away from the direction of the extension line 2A ′ of the shaft 2 in the non-deformed state as the distance from the distal end of the shaft 2 increases. The second portion 4A-3 has a curved shape close to a U shape whose extending direction changes by approximately 180 ° as the distance from the proximal end of the electrode region portion 4B increases. On the other hand, the intermediate region 4A-2 is substantially linear, and forms a predetermined angle α (90 degrees <α <180 degrees) with respect to the extension line 2A ′ of the undeformed shaft 2.

  FIG. 6 illustrates an angle formed by the intermediate region 4A-2 with respect to the extension line 2A ′ of the shaft 2 in an undeformed state and the electrode region portion 4B. The angle α formed by the intermediate region 4A-2 with respect to the extension line 2A ′ is, for example, 105 to 160 degrees, and preferably 110 to 130 degrees.

On the other hand, the angle β formed by the intermediate region 4A-2 with respect to the electrode region portion 4B is, for example, 15 degrees to 90 degrees, preferably 20 degrees to 50 degrees, and they are not parallel to each other.
The connection region portion 4A and the electrode region portion 4B are configured to be included in one plane. This plane coincides with an XZ plane including the shaft 2 (hereinafter simply referred to as an XZ plane) when the shaft 2 is in an undeformed state (FIGS. 1 to 4).

  As shown in FIGS. 3 and 4, the distal portion 4 maintains the state in which the connecting region portion 4 </ b> A and the electrode region portion 4 </ b> B are included in one plane as the movable portion 2 </ b> A of the shaft 2 is bent. , Deflected in a direction deviating from the XZ plane (directions of arrows d3 and d4). Specifically, as the movable portion 2A of the shaft 2 curves in a direction (± Y direction in FIGS. 3 and 4) perpendicular to the XZ plane (XZ plane in FIGS. 3 and 4), the distal portion 4 Is deflected in the direction approaching the XY plane orthogonal to the XZ plane (the directions of arrows d3 and d4). In other words, the movable portion 2A of the shaft 2 is curved in a direction substantially perpendicular to both the extending direction (Z direction) of the non-deformed shaft 2 and the extending direction (X direction) of the electrode region portion 4B. It has become. The movable portion 2A can be curved and deformed until the plane including the distal portion 4 including the connection region portion 4A and the electrode region portion 4B reaches a state AP in which the plane is parallel to the XZ plane. When the shaft 2 is in an undeformed state, the distal portion 4 is arranged in the −Z direction with respect to the movable portion 2A, whereas the distal portion 4 in the state AP is arranged in the + Z direction with respect to the movable portion 2A. The

  The distal portion 4 is composed of a core material for defining the shapes of the connection region portion 4A and the electrode region portion 4B and a resin material that covers the core material. The core material stores a predetermined shape and deforms only while a force is applied. That is, the connection region portion 4A and the electrode region portion 4B of the distal portion 4 are configured to be easily elastically deformed.

Examples of the core material include a nickel (Ni) -titanium (Ti) alloy. The ratio of nickel to titanium is, for example, Ni: Ti = 54: 46 to 57:43. Specifically, nitinol can be used.
The distal end of the core material is fixed to the vicinity of the distal end of the electrode region portion 4B, and the proximal end is fixed to an anchor or the like (not shown) at the connection portion 21 of the shaft 2. In this way, the core material of the distal portion 4 is fixed to a part (connecting portion 21) of the movable portion 2A of the shaft 2, so that the distal portion following the bending operation of the movable portion 2A as described above. The portion 4 can be displaced.
For the resin material covering the core material, for example, a flexible material similar to that of the shaft 2 such as PEBAX can be used, but it is preferable to use a material that is equivalent to or less rigid than the movable portion 2A of the shaft 2. .

  The length and outer diameter of the connecting region portion 4A and the electrode region portion 4B are arbitrary. For example, the length of the connecting region portion 4A is preferably 11 mm to 40 mm, and more preferably 21 mm to 31 mm. The length of the electrode region portion 4B is preferably, for example, 10 mm to 40 mm, and more preferably 20 mm to 30 mm. The central portion of the electrode region portion 4B is disposed on the extension line 2A ′ of the shaft 2, and the lengths of the electrode region portions 4B are equal on both sides of the extension line 2A ′ of the shaft 2 (FIG. 5). The outer diameter of the connection region portion 4A is preferably 0.7 mm to 1.7 mm, and the outer diameter of the electrode region portion 4B is preferably 0.7 mm to 2.0 mm.

[Action / Effect]
(basic action)
First, the usage method of the electrode catheter 1 is demonstrated with reference to FIGS.
In the electrode catheter 1, first, the distal portion 4 is temporarily stretched linearly in the same direction as the non-deformed shaft 2, and then inserted into a cylindrical sheath (not shown). In the state, it is carried to the vicinity of the target site in the heart. Thereafter, when the distal portion 4 is pushed out of the sheath, its shape automatically returns to the mop shape (FIG. 2). In this state, the cardiac potential is measured by the electrodes (ring-shaped electrode 41 and tip electrode 42) of the electrode region portion 4B.

  Specifically, first, the electrode region portion 4B is disposed at a predetermined distance from the heart inner wall S. At this time, for example, the inner wall S as a pressing surface and the plane including the distal portion 4 are arranged so as to be substantially parallel. Next, when the operator operates the rotary knob 32A (FIGS. 1 and 2) of the operation unit 3 to rotate the rotary plate 32 in the direction of the arrow d1 (or arrow d2), one of the operation wires in the shaft 2 is moved. The other part is pulled while being loosened, and the distal portion 4 is displaced in the direction of arrow d3 (or arrow d4) (FIGS. 3 and 4). Thereby, since the electrode region portion 4B is pressed against the inner wall of the heart, the cardiac potential can be measured.

  FIG. 7 shows an example of how to use the electrode catheter 1. In this example, the shaft 2 is advanced without moving the rotating plate 32 (without bending the movable portion 2A of the shaft 2), and the plane including the distal portion 4 is substantially perpendicular to the inner walls S and S '. In this manner, the electrode region portion 4B is pressed against the inner walls S and S ′ of the heart.

In this case, as shown in FIG. 7A, the shaft 2 is advanced as it is toward the inner walls S, S ′ without bending the movable portion 2A of the shaft 2. After the distal end of the electrode region portion 4B of the distal portion 4 contacts the heart inner wall S as shown in (B), the shaft 2 is advanced as it is, and as shown in (C), the electrode region portion 4B. Is fully pressed against the inner wall S of the heart.
Symbol S represents the position when the inner wall of the heart has contracted (moved inward) due to the heartbeat H, and symbol S ′ represents the position when expanded (moved outward).

As shown in FIG. 7C, in a state where the entire electrode region portion 4B of the distal portion 4 is sufficiently pressed against the heart inner wall S at the time of contraction, the heart inner wall S ′ as shown in FIG. When the lens expands outward, the shape of the distal portion 4 is slightly deformed in the restoring direction. For this reason, it is possible to prevent a part or the whole of the electrode region portion 4B from separating from the heart inner wall S ′.
In this way, by performing mapping in which the cardiac potential is measured using the electrode catheter 1, it is possible to find a location where an abnormal potential is generated and identify a line described later.
The followability of the distal portion 4 with respect to the pulsation of the heart is not limited to the case shown in FIG. It will be apparent that this is also demonstrated when performing the above.

  FIG. 8 schematically shows the structure of the heart. There are four rooms in the heart: left atrium LA, right atrium RA, left ventricle LV, and right ventricle RV. Tricuspid valve TV at the entrance of right ventricle RV from right atrium RA, entrance of left ventricle LV from left atrium LA Are provided with mitral valves MV, respectively. For example, many occurrences of abnormal potential such as atrial fibrillation have been confirmed around the pulmonary vein PV in the left atrium LA.

  FIG. 9 schematically shows the configuration of the four pulmonary vein entrances LSPV, RSPV, LIPV, and RIPV of the left atrium LA. In order to block the abnormal potential in the left atrium LA, the roof line Li (Roof line) connecting the pulmonary vein entrance LSPV and the pulmonary vein entrance RSPV, the pulmonary vein entrance LIPV and the pulmonary vein entrance Bottom line Li (Bottom line) connecting the hole RIPV, pulmonary vein inlet RIPV, pulmonary vein inlet LIPV and mitral valve MV Mitral Lewismus line Li (Mitral isthmus line), etc. Ablation is often performed. Ablation is similarly performed for the tricuspid isthmus line Li, which connects the entrance of the inferior vena cava IVC of the right atrium RA, the annular vein, and the tricuspid valve TV. For example, the location of the occurrence of the abnormal potential near the line (line Li) is identified as follows.

  FIG. 10 schematically shows the positional relationship between the line Li on the heart inner wall and the electrode region portion 4B. FIG. 11 shows a state in which the distal portion 4 of the electrode catheter 1 is pressed against the line Li on the inner wall of the heart. 11A shows a perspective state, and FIGS. 11B and 11C respectively show the state of FIG. 11A in the direction of arrow B (X direction) and the direction of arrow C (Z direction). ).

  First, the distal portion 4 is arranged at a predetermined distance from the heart wall surface S (illustrated by a broken line). At this time, the electrode region portion 4B is in a position twisted orthogonally to the line Li, and the electrode region 4B electrodes (ring-shaped electrode 41, tip electrode 42) are on both sides of the line Li. Position portion 4B. Next, the movable plate 2A of the shaft 2 is bent and deformed by moving the rotating plate 32 of the operation unit 3 so that the electrode region portion 4B is pressed against the regions on both sides of the line Li (solid line). In this state, the cardiac potential is measured. Then, the electrocardiogram is measured every time the electrode region portion 4B is moved a little along the line Li. Thereby, mapping can be performed over a wide range, and the location where the abnormal potential occurs on the inner wall of the heart can be specified.

  FIG. 12 schematically shows changes over time in the electrocardiogram measured using a plurality of ring electrodes 41 (ring electrodes 41-1, 41-3, 41-5, 41-7). The axis indicates time t, and the vertical axis indicates the electrode position. In FIG. 12, of the waveforms obtained from the ring electrode 41-3, the waveform A that appears at a timing earlier than the normal timing T1 is an abnormal waveform. Thereby, it can be confirmed that an abnormal potential is generated in the vicinity of the ring-shaped electrode 41-3. Note that the abnormal waveform may appear at a timing later than the normal state.

  As described above, after identifying the line Li including the location where the abnormal potential is generated by mapping with the electrode catheter 1, for example, the electrode region portion 4B of the electrode catheter 1 is arranged along the line Li. Next, using the electrode region portion 4B of the electrode catheter 1 as a mark, the ablation treatment along the line Li is performed with the catheter for ablation treatment, and then the ablation state is confirmed as to whether or not the abnormal potential is blocked. . The ablation state is confirmed using the electrode catheter 1 in the same manner as the above mapping (FIGS. 10 and 11). Specifically, the electrocardiogram is measured by pressing the electrodes (ring-shaped electrode 41, tip electrode 42) of the electrode region portion 4B against the regions on both sides straddling the ablated line (Li).

(Function)
As described above, at the time of mapping, it is necessary to accurately press all the electrodes against the heart wall surface in the vicinity of the line. In this regard, for example, in a catheter in which the electrode region portion is on the extension line of the shaft, when the electrode region portion is pressed against the target portion, a part of the electrode floats and the electrode becomes poor in contact. It is not easy to press against the heart wall accurately.

  On the other hand, in the electrode catheter 1 of the present embodiment, the electrode region portion 4B is substantially orthogonal so as to straddle the extension line 2A ′ of the shaft 2 when not in operation (non-deformed state), and the distal end side of the catheter is mop. Therefore, it is easy to apply force evenly to the entire electrode region portion 4B, and a part of the electrode region portion 4B can be prevented from being lifted. That is, it is easy to apply an equal pressing force by bringing the entire electrode region portion 4B into contact with a desired location on the heart wall surface.

  Therefore, for example, in mapping before ablation treatment, the cardiac potential can be accurately measured by pressing the electrode region portion 4B evenly and accurately against the heart wall surface in the vicinity of the line Li, and identification of the location where the abnormal potential is generated Is accurate and easy. Similarly, when the ablation state is confirmed after the ablation treatment, it is easy to accurately confirm that the abnormal potential has been properly blocked. Moreover, in the electrode catheter 1, since the front end side has a mop shape, it is easy to measure the electric potential on both sides across the line over a wide area along the line Li.

  In the present embodiment, as shown in FIG. 5, the electrode region portion 4B of the distal portion 4 is in an undeformed state so that the distal end (tip) is farther from the shaft 2 than the proximal end. An angle θ of less than 90 ° is formed with respect to the extension line 2A ′ of the shaft 2. For this reason, as shown in FIGS. 7 (A) to 7 (C), when the electrode region portion 4B is pressed against the wall surface of the heart, it comes into contact with the inner wall of the heart sequentially from its distal end, It is possible to prevent the distal end of the electrode region portion 4B from rising from the inner wall of the heart.

  On the other hand, if the angle θ is larger than 90 degrees, the distal end of the electrode region portion 4B comes into contact with the pressing surface later than the other portions. Even if it is pressed strongly enough, the distal end (tip) of the electrode region portion 4B may remain away from the inner wall of the heart.

Thus, in the present embodiment, as described above, the distal end of the electrode region portion 4B hardly rises from the inner wall of the heart, and the electrode region portion 4B can be accurately pressed to a desired location on the inner wall of the heart. Therefore, the electrocardiogram can be measured efficiently, easily and accurately.
However, if the angle θ is too small and the electrode region portion 4B is inclined too much from the direction orthogonal to the extension line 2A ′, the tip of the electrode region portion 4B tends to abut against the inner wall of the heart, so that the angle does not fall below 70 degrees, for example. It is preferable to set θ. In this case, since the time from the contact of the distal end of the electrode region portion 4B to the contact of the entire electrode region portion 4B with the inner wall of the heart is relatively short, the cardiac potential can be measured more efficiently. There is also a merit.

  In the present embodiment, as shown in FIG. 6, both the first portion 4A-1 and the second portion 4A-3 at both ends of the connecting region portion 4A are made of an elastic material having a curved shape. The angle α formed by the intermediate portion 4A-2 of the connecting region portion 4A with respect to the extension line 2A ′ of the undeformed shaft 2 and the angle β formed by the intermediate portion 4A-2 with respect to the electrode region portion 4B are appropriately set. It is set in a range. For this reason, the pressing force when the electrode region portion 4B is pressed against the inner wall of the heart is transmitted to the entire pressing portion. Hereinafter, this point will be described in detail.

  First, in the present embodiment, the angle α at which the intermediate portion 4A-2 of the connection region portion 4A of the distal portion 4 is inclined with respect to the extension line 2A ′ of the shaft 2 in the non-deformed state when not in use. (90 degrees <α <180 degrees). Therefore, compared with the case where the angle α is 90 degrees, the elastic force of the first portion 4A-1 when the electrode region portion 4B is pressed against the inner wall of the heart is sufficiently secured, and the first portion 4A. The allowable distance range in which the elastic force of -1 can effectively and appropriately act on the inner wall of the heart (hereinafter referred to as the effective movable range of the electrode region portion 4B) is increased. As a result, for example, as already described with reference to FIG. 7, in the state where the entire electrode region portion 4B of the distal portion 4 is pressed against the heart inner wall S during contraction (FIG. 7C), the inner wall of the heart Even if S ′ expands outward, the shape of the distal portion 4 is deformed in the restoring direction following the movement (FIG. (D)), so that a part or the whole of the electrode region portion 4B is the heart inner wall S ′. There is little possibility of leaving. That is, it is avoided that the electrocardiographic measurement becomes unstable due to the pulsation of the heart.

  When the angle α is 180 degrees, that is, when the intermediate portion 4A-2 and the first portion 4A-1 extend linearly so as to coincide with the axial direction of the shaft 2 in the non-deformed state. Since there is no room for the first portion 4A-1 to exhibit elasticity, it is meaningful to make the angle α less than 180 degrees as in the present embodiment, even in this case.

  If the angle α is too close to 180 degrees, the elastic force of the first part 4A-1 is too large, and if the angle α is too close to 90 degrees, the elastic force of the first part 4A-1 becomes insufficient. Since the allowable range of the distance at which the elastic force of the 1 part 4A-1 can act on the inner wall of the heart becomes small, the angle α is more preferably designed to be, for example, about 110 degrees to 130 degrees in consideration of these.

  Second, in the present embodiment, the intermediate portion 4A-2 of the connection region portion 4A of the distal portion 4 and the electrode region portion 4B are not parallel when not in use. Specifically, the angle β between the intermediate portion 4A-2 and the electrode region portion 4B is set to about 20 to 50 degrees, for example. By doing so, the insufficient pressing force at the distal end of the electrode region portion 4B can be compensated. For example, when the intermediate portion 4A-2 and the electrode region portion 4B are parallel, when the electrode region portion 4B is pressed against the heart inner wall S, the elastic force of the second portion 4A-2 is hardly exhibited. Although the pressing force at the distal end of the electrode region portion 4B is insufficient, if the intermediate portion 4A-2 and the electrode region portion 4B are made non-parallel as in the present embodiment, the distal end of the electrode region portion 4B Insufficient pressing force is compensated. That is, a predetermined pressing force is ensured over the entire electrode region portion 4B.

  In the present embodiment, since the first portion 4A-1 and the second portion 4A-3 are formed in an arc shape (curved shape), the stress generated in the connection region portion 4A when the electrode region portion 4B is pressed. Is dispersed throughout the connecting region portion 4A. Therefore, for example, in the present embodiment, the first portion 4A-1 and the second portion 4A-3 are compared with the case where the first portion 4A-1 and the second portion 4A-3 are configured to form a straight crossing angle. It is possible to suppress local stress concentration on the surface. Therefore, durability of the distal portion 4 of the electrode catheter 1 can be enhanced. In addition, since the first portion 4A-1 and the second portion 4A-3 are smoothly curved, there is an advantage that the contact with the inner wall of the heart becomes gentle.

  Thus, according to the present embodiment, the connecting region portion 4A has the two first portions 4A-1 and 4A-3 that can be elastically deformed at both ends thereof. The effective range of motion of 4B can be increased, and at the same time, a pressing force on the inner wall of the heart can be secured over the entire electrode region portion 4B. For this reason, as described above, the electrode region portion 4B is displaced following the pulsation of the heart (FIGS. 7C and 7D). For example, even when the heart is expanded, The contact state with the heart inner wall S ′ is maintained. Therefore, the electrocardiogram can be measured efficiently, accurately and easily even in mapping before ablation or in a scene of ablation status confirmation (confirmation of blocking of abnormal potential) after ablation.

Next, other features will be described.
In the electrode catheter 1 of the present embodiment, the movable portion 2A of the shaft 2 can be bent and deformed by the operation of the operation portion 3. Therefore, the distal portion 4 can be deflected in a direction substantially orthogonal to the XZ plane (a plane including the undeformed shaft 2 and the distal portion 4, the XZ plane in FIGS. 3 and 4).

  Specifically, for example, as illustrated in FIG. 11, the electrode region portion 4 </ b> B can be easily moved in the direction along the line Li by the operation of the rotary knob 32 </ b> A of the operation unit 3. More specifically, by further bending the movable portion 2A in the direction of the arrow M2 from the state in which the electrode region portion 4B is pressed against the line Li on the inner wall of the heart (solid line in the figure), the electrode region portion 4B is It is easy to move so as to trace the inner wall S along the line (dashed line in the figure).

  For example, when it is assumed that the shaft does not bend and deform, in order to move the distal portion 4 along the line Li, the operator moves the entire electrode catheter, and measures the potentials on both sides across the line Li. There must be. In this case, the shaft 2 is likely to be laterally shifted during the measurement, so that the distance between the line Li and each electrode is likely to be shifted, and there is a possibility that accurate measurement cannot be performed.

  On the other hand, in the electrode catheter 1 of the present embodiment, the electrode region portion 4B is moved along the line Li by gradually bending and deforming the movable portion 2A on the distal end side of the shaft without moving the entire electrode catheter. There are cases that can be made. In such a case, the potential can be measured while accurately maintaining the distance between the line Li and each electrode (ring-shaped electrode 41, tip electrode 42) of the electrode region portion 4B. In this case, since the electrode region portion 4B can be smoothly moved along the line Li according to the operation amount of the rotary knob 32A of the operation unit 3, the interval between the measurement positions can be miniaturized.

  Further, by adjusting the degree of curvature of the movable portion 2A by operating the rotary knob 32A of the operation portion 3, the electrode region is adjusted in accordance with the undulation of the heart inner wall S while maintaining the contact between the wall surface S and the electrode region portion 4B. It is also possible to move the portion 4B.

  In the present embodiment, as shown in FIG. 11, the operation unit starts from a state (shown by a broken line) in which the plane including the distal portion 4 is spaced apart and substantially parallel to the region including the line Li of the inner wall S. The entire electrode region portion 4B can be easily deflected in the direction of the arrow M1 by only the operation 3 and can be brought into contact with the inner wall of the heart. That is, the electrode catheter 1 has a high degree of freedom of operability that allows the electrode region portion 4B to be easily pressed against various places in a narrow heart.

  Further, for example, if the distal portion is displaced in the XZ plane including the non-deformed shaft (XZ plane in FIGS. 3 and 4), the linear electrode region portion is in the XZ plane. Will move in. For this reason, in the narrow heart, there is a possibility that the tip (tip electrode) of the electrode region portion contacts the inner wall of the heart and is stimulated. Such stimulation may cause extra-systole. On the other hand, in the present embodiment, since the distal portion 4 is displaced in a direction substantially orthogonal to the XZ plane, the operational risk as described above can be reduced. That is, according to the electrode catheter 1, it is possible to realize operability with a small surgical risk while ensuring a high degree of freedom.

  FIG. 13 schematically shows how the distal portion 4 of the electrode catheter 1 inserted into the heart through the septal puncture hole H is pressed against the wall surfaces S1, S2, and S3. As described above, by operating the operation unit 3, the electrode region portion 4B can be easily and safely pressed even in the heart inner wall S1 in the immediate vicinity of the septal puncture hole H into which the electrode catheter 1 is inserted. . Further, by the operation of the operation unit 3, the electrode region portion 4B can be efficiently and accurately pressed even on the inner heart walls S2 and S3 at positions away from the wall surface S1. That is, the degree of freedom of operation during the treatment is high.

  As described above, in the present embodiment, since the electrode region portion 4B is provided so as to straddle the extension line 2A ′ of the shaft 2 in the non-deformed state, the electrode region portion 4B can be pressed accurately to a desired location. . Therefore, when mapping or confirming the ablation state after ablation treatment, the electrode region portion 4B can be easily pressed evenly on both sides of the line, efficiently and accurately. The cardiac potential can be measured.

  In the present embodiment, the movable portion 2A of the shaft 2 can be bent and deformed by the operation of the operation portion 3, and the distal portion 4 can be deflected in a direction substantially perpendicular to the XZ plane. Degrees can be realized.

Further, in the present embodiment, since the two first portions 4A-1 and 4A-3 that can be elastically deformed are provided at both ends of the connection region portion 4A of the distal portion 4, the electrode region portion The expansion of the effective movable range of 4B and the predetermined pressing force over the entire electrode region portion 4B can be realized simultaneously.
That is, according to the electrode catheter 1 of the present embodiment, it is possible to easily and efficiently perform an accurate electrocardiogram measurement.

  Hereinafter, modifications of the present embodiment will be described. In the following description, the same components as those in the above embodiment are given the same reference numerals, and the description thereof is omitted as appropriate.

<Modification 1>
FIG. 14 illustrates a planar configuration of the distal portion 4 of the electrode catheter 1 according to the first modification. As shown in this figure, the electrode region portion 4B may not be a complete straight line, and may be gently curved so as to be convex on the opposite side to the shaft 2, for example. In this case, there is a merit in that all the electrodes in the electrode region portion 4B can easily come into contact with the inner wall of the heart. Note that the gentle curve of the electrode region portion 4B may be adjusted so as to follow a curve of a specific target region in the inner wall of the heart, for example.

<Modification 2>
FIG. 15 illustrates a planar configuration of the main part of the electrode catheter 1 according to the second modification. In this electrode catheter 1, the distal end of the shaft 2 and the electrode region portion 4B form a linear intersection angle, and similarly, the electrode region portion 4B and the connection region portion 4A have a linear intersection angle. Forming part. That is, the first portion 4A-1 is linearly directed from the distal end of the shaft 2 to the electrode region portion 4B, and the second portion 4A-3 is bent in a substantially V shape. However, as described with reference to FIG. 5 above, the first portion 4A-1 and the second portion 4A-3 may be formed in a curved shape in order to avoid local stress concentration at the crossing corner. preferable.

<Modification 3>
FIG. 16 illustrates a planar configuration of the distal portion 4 of the electrode catheter 1 according to Modification 3. In the distal portion 4, the length of the electrode region portion 4 </ b> B is different on both sides of the extension line 2 </ b> A ′ of the undeformed shaft 2. However, in order to apply the pressing force evenly to the entire electrode region portion 4B, as shown in FIG. 5, the electrodes are made so that the lengths on both sides of the extension line 2A ′ of the shaft 2 in the non-deformed state are substantially equal. It is preferable to constitute the region portion 4B.

<Modification 4>
FIG. 17 illustrates a planar configuration of the distal portion 4 of the electrode catheter 1 according to Modification 4. In this way, the distal portion 4B of the electrode region portion may be orthogonal to the extension line 2A ′ of the shaft 2 in the non-deformed state.

<Other variations>
Although the present invention has been described with reference to the embodiment and the modifications, the present invention is not limited to this embodiment, and various modifications can be made. For example, the above material may be another material. In the above embodiment, the configuration of the electrode catheter (shaft) has been specifically described. However, it is not always necessary to include all the members, for example, when the bending deformation direction of the movable portion 2A is one direction. Alternatively, a single operation wire may be used. Furthermore, in addition to the above configuration, other members may be provided.

  In the above embodiment, the configuration of the electrodes in the electrode region portion 4B of the distal portion 4 has been specifically described. However, the arrangement, position, interval, shape, number, and the like of the ring-shaped electrode 41 and the tip electrode 42 are described. Is not limited to this. The electrode region portion 4B only needs to have two or more electrodes.

  In addition, Modifications 1 to 4 such as Modification 1 (FIG. 14) and Modification 4 (FIG. 17), Modification 2 (FIG. 15) and Modification 4 or Modification 3 (FIG. 16), Modification 4 and the like. These may be combined to form an electrode catheter. It is also possible to combine three or more of the first to fourth modifications.

  DESCRIPTION OF SYMBOLS 1 ... Electrode catheter, 2 ... Shaft, 21 ... Connection part, 2A ... Movable part, 3 ... Operation part, 31 ... Handle, 32 ... Rotary plate, 4 ... Distal part, 4A ... Connection area | region part, 4B ... Electrode area | region part , 41 ... ring-shaped electrode, 42 ... tip electrode.

Claims (9)

An operation unit;
A linear shaft having a proximal end connected to the operation portion and a predetermined section portion on the distal end side configured to be freely deformable by operation of the operation portion;
A linear distal portion coupled to the distal end of the shaft and configured to be included in a plane including the undeformed shaft;
The distal portion is
A linear electrode region portion configured to have a plurality of electrodes and to straddle the extension line in a substantially orthogonal direction when the shaft is in a non-deformed state;
A connecting region portion connecting the proximal end of the electrode region portion and the distal end of the shaft;
The electrode catheter in which a bending deformation direction of the predetermined section portion of the shaft is a direction substantially orthogonal to the one plane. The electrode catheter according to claim 1, wherein at least one of the connection region portion and the electrode region portion is elastically deformable. The connecting region portion is
An elastically deformable first portion on the shaft side;
An elastically deformable second part on the electrode region part side;
The electrode catheter according to claim 1, further comprising: a linear intermediate portion that is located between the first portion and the second portion and is not parallel to the electrode region portion. An angle formed by an intermediate portion of the connection region portion and the electrode region portion is 20 degrees to 50 degrees,
The electrode catheter according to claim 3, wherein an angle formed between an intermediate portion of the connection region portion and the shaft in a non-deformed state is 110 degrees to 130 degrees. The connection region portion is curved in an S shape so as to smoothly connect the proximal end of the electrode region portion and the distal end of the shaft. Electrode catheter. The electrode region portion has an angle of less than 90 degrees with respect to an undeformed extension of the shaft such that the distal end of the electrode region portion is further from the shaft than the proximal end of the electrode region portion. The electrode catheter according to any one of claims 1 to 5, wherein the electrode catheter is provided. The electrode catheter according to claim 6, wherein the electrode region portion is provided so as to form an angle of 70 degrees or more with respect to an extension line of the shaft in a non-deformed state. The electrode catheter according to any one of claims 1 to 7, wherein the electrode region portion is gently curved so as to be convex on the opposite side to the shaft. The electrode catheter according to any one of claims 1 to 8, wherein the length of the electrode region portion is equal on both sides of an extension line of the shaft in an undeformed state.

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