Entry into the interventricular septum using a puncture catheter device.

Abstract

The present invention provides an apparatus and method for creating a transvenous access route within the interventricular septum of a patient's heart. [Solution] This method uses a catheter device that is operable at its distal end. The puncture device passes through the coronary sinus and enters a coronary vein (e.g., a great cardiac vein), then is advanced through the catheter device and punctures the vein wall. To facilitate this puncture, the distal end of the catheter device may be bent at an angle toward the vein wall. The puncture device is pushed to perforate the myocardium toward the interventricular septum. This perforation creates an entry passage from the coronary vein through the myocardium into the interventricular septum. This entry passage may be used for insertion of an electrode lead or a mitral valve loop circular wire.

Description

Technical Field

[0001] The present invention relates to a catheter device for performing transvascular cardiac surgery.

Background Art

[0002] With the recent development of interventional cardiology, there is a need to create a transvenous access route within the ventricular septum of a patient's heart. For example, this route can be used for novel catheter-based treatments such as mitral valve loop circumclage, physiological pacing, or septal reduction by radiofrequency (RF) ablation within the septum for mitral regurgitation. This technique is relatively easier when the patient has a septal perforating vein within the ventricular septum. However, when the patient does not have a suitable septal perforating vein within the ventricular septum, this technique becomes more difficult. Therefore, a more general technique for creating a transvenous access route that can be used for patients regardless of the presence or absence of a suitable septal perforating vein is needed.

Summary of the Invention

[0003] The present invention is for creating a transvenous access route within the ventricular septum of a patient's heart. There are various different types of cardiac surgeries for which such an access route can be beneficial, such as cardiac pacing, RF (radiofrequency) ablation, or mitral valve circumclage surgery. These surgeries are described in more detail below. The method uses a catheter device that is operable at its distal end. An example of a catheter device that can be used includes those described in International Publication No. WO 2021 / 119636 of the patent application published under the name "Septal Cross System" (Tau Cardio, Inc.), which is incorporated herein by reference. Other examples of catheter devices that can be used are further described herein.

[0004] This catheter device comprises a main tube having a distal end segment, a distal end, and a lumen. As used herein, the “distal end segment” refers to the portion of the main tube encompassing the area from the distal end of the main tube to a distance of 5 cm medially (proximal) from the distal end. The length of the main tube may be in the range of 60 to 180 cm. This catheter device further comprises a puncture device that passes through the lumen. The puncture device may be inserted into the lumen of the catheter device at any preferred stage of cardiac surgery.

[0005] The main vessel is inserted into an inlet vein (such as the femoral vein, subclavian vein, or jugular vein). The main vessel is then advanced into a superior vena cava (superior or inferior vena cava). The main vessel is then advanced into the right atrium of the heart. From the right atrium, the main vessel is inserted into the coronary sinus and advanced through the coronary veins. Examples of coronary veins that can be traversed include tributaries that flow into the coronary sinus, such as the great cardiac vein, left ventricular vein, middle cardiac vein, left marginal vein, and septal vein.

[0006] The distal tip is positioned at a target site within the coronary vein near the interventricular septum (e.g., within 4.0 cm). The lancet is introduced into the catheter device so that it passes through the lumen of the main vein. The lancet may be any type of wire-like instrument capable of penetrating the vein wall and into the myocardium. For example, the lancet may be a wire, a drill bit, or a sharp needle tip.

[0007] The lancet is advanced distally along the main vein's lumen (i.e., through the superior vena cava, right atrium, coronary sinus, and coronary veins). The lancet is advanced out of the distal opening of the main vein and pushed to puncture the vein wall. The lancet is then advanced further into the myocardium toward the interventricular septum. This creates an entry passage from the coronary vein through the myocardium into the interventricular septum.

[0008] Any suitable amount of force may be used to puncture through the vein wall. In situations where the patient has a septal vein and the distal end of the main tube is positioned within the septal vein, a relatively small force may be required. For example, the force applied to puncture through the vein wall may be less than 0.20 N (Newtons). In other situations (e.g., when the patient does not have a septal vein), a relatively large force may be required. For example, the force applied to puncture through the vein wall may be in the range of 0.20 to 1.25 N (Newtons). This amount of force may be suitable in situations where the distal end of the main tube is within the great cardiac vein and puncture of the wall through the great cardiac vein is required. To apply the force, the opposing wall of the coronary vein may be used as a support wall in the distal end segment of the main tube.

[0009] In some embodiments, at the target site for venous wall puncture, the distal end segment of the main tube is bent at an angle with respect to the longitudinal axis of the main tube. Thus, the distal tip opening is directed at an angle toward the venous wall. For example, this angle may be at least 45° with respect to the longitudinal axis of the main tube. With the main tube bent in this manner, the puncture device is advanced at an angle toward the venous wall and punctures through the venous wall.

[0010] In some embodiments, the main tube is provided with a flexible segment at its distal end segment. The flexible segment may be manufactured to bend under operator control (e.g., like an operable tip). In some cases, the flexible segment is more flexible than other segments of the main tube proximal to the flexible segment (e.g., the flexible segment is more flexible than other parts of the main tube). In some cases, the main tube is provided with a coil element at its flexible segment. Having a coil element gives the flexible segment spring-like extensibility, improving the maneuverability of the catheter device. In some cases, the length of the flexible segment is in the range of 10 to 40 mm.

[0011] In some embodiments, the main tube includes a pre-formed C-shaped curved segment extending from a proximal point A to a distal point B. Point A is located within 6.0–15 cm from the distal end of the main tube. Point B is located within 0.4–4.0 cm from the distal end of the main tube. Point B is located distal to point A. The length of the C-shaped curved segment (distance from point A to point B) may be in the range of 5–20 cm. In some cases, the operating wire is positioned within the internal curve of the C-shaped curve. During use, the main tube is inserted into the coronary sinus so that the C-shaped curve of the main tube follows the curve of the coronary sinus. This pre-formed C-shaped curve can help set the main tube at a good angle toward the coronary sinus and provide torque capacity through the coronary vein.

[0012] In some embodiments, the catheter device further comprises a manipulative wire that acts to cause a bend in the main tube. The manipulative wire is fixed to the main tube at the distal end segment of the main tube. The bend is acted upon by pushing or pulling the manipulative wire. Depending on the detailed configuration of the catheter device, straightening or bending may be achieved by pushing or pulling. The distal end of the manipulative wire is attached to the main tube near the distal tip of the main tube. In some cases, the distal end of the manipulative wire is attached to the main tube at a position within 1.5 cm of the distal tip of the main tube. The length of the manipulative wire may be in the range of 80 to 200 cm. The length of the manipulative wire may be shorter than the length of the puncture device.

[0013] In some embodiments, the catheter device further comprises a handle assembly equipped with an operating actuator. The operating wire is coupled to the operating actuator, which works to push or pull the operating wire. The operating actuator may have any preferred components such as a knob, dial, slider, or lever to perform this action.

[0014] In some embodiments, the main tube further comprises a second lumen separate from the (first) lumen. The operating wire passes through the separate second lumen of the main tube. In some cases, the main tube comprises an exit hole from the second lumen. The operating wire exits the second lumen through the exit hole. This exit hole may be located within 4 to 40 mm from the distal end of the main tube.

[0015] In some embodiments, the distal end segment of the main tube comprises two or more radiopaque markers. The distance between the markers may be in the range of 2 to 8 mm. In some cases, the main tube comprises at least three radiopaque markers. These radiopaque markers may be beneficial in that the operator can evaluate the degree of curvature by imaging under X-ray fluoroscopy. The amount of deviation of the radiopaque markers from a linear arrangement indicates the degree of curvature.

[0016] In some embodiments, a catheter device is used to perform cardiac venography. With the distal end of the main catheter located within the coronary sinus or further into the coronary vein, a contrast agent is injected into the coronary vein through the catheter device. In some cases, pressurized venography is performed by placing an obstruction at or near (within 1.5 cm of) the coronary sinus ostium. This allows for better visualization of smaller distal branch veins of the coronary sinus.

[0017] In some embodiments, this method is used to insert an electrode lead into a patient's heart. Examples of electrode leads include those used for cardiac pacing or RF (radiofrequency) ablation. The method involves introducing the electrode lead into a catheter device such that the electrode lead travels along the same path along the main lumen, then through an inlet passage in the myocardium, and into the interventricular septum. The electrode of the electrode lead is positioned inside the interventricular septum. In situations where the same lumen is used to advance the electrode lead, the puncture device is withdrawn from the catheter device, and the electrode lead is advanced through this same lumen of the main lumen.

[0018] Cardiac pacing within the interventricular septum may be beneficial in treating cardiac rhythm abnormalities. For example, the above treatment may be para-Hisian pacing of the right ventricle adjacent to the bundle of His or the proximal right bundle branch (RBB). This para-Hisian pacing may be beneficial in patients with atrioventricular (AV) block as the cause of the cardiac rhythm abnormality. Radiofrequency ablation (RF) in the interventricular septum may be beneficial in treating various cardiac conditions, such as hypertrophic cardiomyopathy.

[0019] In some embodiments, this method is used for mitral valve cerclage surgery. Examples of such surgeries are described in Kim et al., “Mitral cerclage annuloplasty, a novel transcatheter treatment for secondary mitral valve regurgitation: Initial results in swine” (2009) J Am Coll Cardiol. 54(7):638-651, and Park et al., “Mitral Loop Cerclage Annuloplasty for Secondary Mitral Regurgitation: First Human Results” (2017) JACCCardiovasc Interv. 10(6):597-610. These publications are incorporated herein by reference.

[0020] This method involves introducing a mitral valve loop circular wire into a catheter device such that the mitral valve loop circular wire follows the same path along the main lumen, then passes through an inlet passage in the myocardium, and enters the interventricular septum. The mitral valve loop circular wire may then exit outside the interventricular septum to form a desired loop. In situations where the same lumen is used to advance the circular wire, the puncture device is withdrawn from the catheter device, and the circular wire is advanced through this same lumen of the main lumen. [Brief explanation of the drawing]

[0021] [Figure 1] It is an overall view of the catheter device. [Figure 2] It is a detailed side view of the distal portion of the catheter device. [Figure 3] It is a detailed cross-sectional view of the distal portion of the catheter device. [Figure 4] It is a diagram showing the bending operation of the catheter device. Figure 4 shows the twist knob in the standby position with no tension applied to the operating wire. [Figure 5] It is a diagram showing the bending operation of the catheter device. Figure 5 shows the slider moving backward. [Figure 6] It is a diagram showing the bending operation of the catheter device. Figure 6 shows the distal tip of the main tube angled and deflected. [Figure 7] It is a detailed view of the bendable segment. Figure 7 shows the bendable segment bent at a 90° angle. [Figure 8] It is a detailed view of the bendable segment. Figure 8 shows the bendable segment further flexed to bend at a 135° angle. [Figure 9] It is a diagram showing an example of how the operating mechanism can work. Figure 9 shows the main tube inside the coronary vein. [Figure 10] It is a diagram showing an example of how the operating mechanism can work. Figure 10 shows the puncture device inside the main tube in the bending state. [Figure 11] It is a diagram showing an example of how the operating mechanism can work. Figure 11 shows further bending of the main tube to point at a steeper angle towards the myocardium. [Figure 12] It is a diagram showing a cross-section of the heart and illustrating an example of the overall insertion procedure of the catheter device. [Figure 13] It is a diagram showing how an external ultrasonic probe can be used by an operator to assist in guiding the puncture procedure. [Figure 14]This figure shows how the flexible segment of the main tube is designed to bend when the operating wire is pulled back. Figure 14 shows the main tube in a relaxed position (without tension applied). [Figure 15] This figure shows how the bendable segment of the main pipe is designed to bend when the operating wire is pulled back. Figure 15 shows the bending of the main pipe caused by the pulling back of the operating wire. [Figure 16] Figure 16 shows how the bendable segment of the main pipe is constructed to bend as the operating wire is pulled back. Figure 16 shows the further bending of the main pipe as the operating wire is pulled back further. [Figure 17] This figure shows an example of a conventional cardiac pacemaker device that can be implanted using a catheter device. [Modes for carrying out the invention]

[0022] [Detailed description of exemplary embodiments] To aid in understanding the present invention, references are made to the accompanying drawings to illustrate specific embodiments in which the invention may be carried out. The drawings herein are not necessarily drawn to scale or to actual proportions. For example, the lengths and widths of components may have been adjusted to correspond to page dimensions.

[0023] Figure 1 shows an example of a catheter device 10 for creating a transvenous access route within the interventricular septum of a patient's heart. The orientation of the proximal end 13 and distal end 11 relative to the catheter device 10 is shown. Towards the distal end 11, the catheter device 10 comprises a flexible main tube 20 having multiple (two or more) lumens inside. This configuration defines the longitudinal axis 21 (straight vertical in this drawing) of the main tube 20. The main tube 20 comprises a bendable segment 34. The catheter device 10 also comprises a manipulating wire 40 for manipulating the bendable segment 34 of the main tube 20.

[0024] Towards the proximal end 13, the catheter device 10 comprises a handle assembly 50 having a conical hood 88 to which the main tube 20 is attached. The handle assembly 50 further comprises a handle grip 86. On the underside of the handle assembly 50 is a hub 56 having a main port 84 and a secondary port 82. A guidewire and a puncture device (not shown) are inserted into the main port 84, which is an opening for the first lumen 26 (not shown) of the main tube 20. The handle assembly 50 comprises a twist knob 52 and a slider 54. Inside the twist knob 52 is a helical rail 80. The twist knob 52 engages with the slider 54 on the helical rail 80. In this configuration, turning the twist knob 52 (clockwise or counterclockwise) drives the slider 54 forward or backward by the helical rail 80. As will be explained in more detail below, this movement results in a bend in the bendable segment 34 of the main pipe 20.

[0025] Figures 2A and 2B show detailed views of the distal portion of the catheter device 10. As shown here, the main tube 20 has a distal tip 20a with an opening 25. The opening 25 is part of a first lumen 26 through which a puncture device 44 (not shown) passes. An electrode lead or circular wire may be inserted into this same first lumen 26 used by the puncture device 44 (after the puncture device 44 has been withdrawn). In addition to the first lumen 26 for the puncture device 44 (not shown), the main tube 20 has a second lumen 28 for the manipulative wire 40. The second lumen 28 has a proximal opening 24 which serves as an exit hole from the second lumen 28.

[0026] The operating wire 40 exits the second lumen 28 through the proximal hole 24 and runs alongside the main body of the main tube 20, passing outside the main body of the main tube 20. The operating wire 40 re-enters the main body 20 through the distal hole 22. The distal end of the operating wire 40 is embedded inside the main tube 20. This ensures that the distal end of the operating wire 40 is attached near the distal tip 20a of the main tube 20. The distal hole 22 is unnecessary for attaching the operating wire 40 to the main tube 20. For example, in another embodiment, the distal end of the operating wire 40 may be attached to the outer surface of the main tube 20 at or near its distal tip 20a.

[0027] Figures 2 and 3 also show some relevant dimensions of the catheter device 10. The total length L2 of the main tube 20 is approximately 120 cm. The length L3 of the bendable segment 34 is approximately 18 mm. The length L1 of the manipulator wire 40 is longer than the length L2 of the main tube 20. Here, the length L1 of the manipulator wire 40 is approximately 150 cm. The portion of the manipulator wire 40 that passes outside the body of the main tube 20 (between side holes 22 and 24) is approximately 12 mm in length (when the main tube 20 is in a straight configuration). The distance from the proximal side hole 24 to the distal tip 20a of the main tube 20 is approximately 15 mm. The length of the second lumen 28 (for the manipulator wire 40) is shorter than the length of the first lumen 26 for the puncture device 44. These figures also show the metal coil 30 inside the bendable segment 34 of the main tube 20. The metal coil 30 provides elastic flexibility to the bendable segment, i.e., makes the bendable segment 34 elastically deformable. These figures also show three radiopaque markers 32.

[0028] The main vessel 20 also has a pre-formed C-shaped curved segment 88. That is, the main vessel 20 tends to form a C shape in this curved segment 88. This curved segment 88 encompasses a portion of the main vessel 20 from the proximal end of the flexible segment 34 to a point even more proximal thereto. In this example, the C-shaped curved segment 88 has a length L4 of approximately 10 cm. This C-shaped curve conforms to the natural curved passage of the coronary sinus. Having this C-shaped curve can be beneficial in ensuring that when venous puncture is performed, the bend in the flexible segment 34 directs the main axis 20 so that its distal end points precisely medially toward the interventricular septum.

[0029] The main tube 20 has three 1.0 mm wide radiopaque marker bands 32 for imaging under X-ray fluoroscopy. These radiopaque marker bands 32 allow the operator to assess the position of the distal end of the main tube 20. Here, the marker bands 32 are spaced approximately 5 mm apart. Having multiple spaced-out marker bands 32 also allows the operator to assess the shape of the distal end of the main tube 20, i.e., its degree of curvature. For example, a linear arrangement of the three marker bands 32 would indicate that the distal end of the main tube 20 is not curved. However, three marker bands 32 that are not in a linear arrangement would give the operator an estimate of the degree of curvature.

[0030] Figures 4 to 6 show the bending motion of the catheter device 10. The main tube 20 and the first lumen 26 contained within it are shown here. Also shown is the manipulative wire 40 passing through a separate second lumen 28 of the main tube. The manipulative wire 40 passes through the proximal hole 24, exits the second lumen 28, and is fixed to the main tube 20 at the distal hole 22. The twist knob 52 holds a slider 54 that engages with a spiral rail 80 inside the twist knob 52. By rotating the twist knob 52, the slider 54 moves back and forth. The proximal end of the manipulative wire 40 is attached to the slider 54. Due to this operating mechanism, the manipulative wire 40 is pushed or pulled by turning the twist knob 52. This is the operating control mechanism for the catheter device 10.

[0031] In Figure 4, the twist knob 52 is in a standby position with no tension applied to the operating wire 40. The main tube 20 is in a relaxed state with no forced bending at its distal end. In Figure 5, when the twist knob 52 is twisted by the operator, the slider 54 slides backward along the rail 80. This sliding causes the slider 54 to pull the operating wire 40 backward. The tension applied to the operating wire 40 causes its distal end to pull back the distal tip 20a of the main tube 20. This bending causes the bendable segment 34 of the main tube 20 to form a C-shaped curve, orienting its distal tip 20a away from the longitudinal axis of the main tube 20.

[0032] In Figure 6, with the distal tip 20a deflected at an angle, the lancing device 44 is advanced so as to exit the opening at the distal tip 20a of the main tube 20. The C-shaped bend in the flexible segment 34 of the main tube 20 causes the lancing device 44 to be oriented at an angle to the longitudinal axis of the main tube 20. As can be seen here, the length of the manipulating wire 40 is shorter than the length of the lancing device 44.

[0033] Figures 7 and 8 are detailed views of the bendable segment 34. The main tube 20 is equipped with a coil element 30 on the bendable segment 34. This coil element 30 facilitates operation by functioning as a spring-like reaction. This coil element 30 may be embedded in the wall of the main tube 20 or may be a sheath around the first lumen 26 (not shown here). The coil element 30 may wrap around the first lumen 26 in a spiral manner, be coaxial with the first lumen 26 (common axis), and function to reinforce the first lumen 26. The operating wire 40 exits the main tube 20 through a side hole 24 and travels outside the main body of the main tube 20. The operating wire 40 is then attached to the main tube 20 at a further distal point.

[0034] In Figure 7, the flexible segment 34 is bent at an angle of 90° with respect to the initial 0° starting point (i.e., the longitudinal axis) when the main tube 20 is in a straight state. In Figure 8, the flexible segment 34 is further bent, bending at an angle of 135° from the initial 0° starting point. As seen herein, the puncture device 44 is oriented at different angles due to the bending of the flexible segment 34. The most distal of the three radiopaque markers 32 is also shown here. As seen here, the coil element 30 is located distal to the side hole 24 through which the operating wire 40 exits the main tube 20. The puncture device 44 assembled with the catheter device 10 may be considered as a septal puncture assembly in another aspect of the present invention.

[0035] Figures 9 to 11 illustrate how the manipulating mechanism can orient the puncture device 44 in an angled direction. Figure 9 shows the main tube 20 inside the coronary vein 72 surrounded by the vein wall 70. The main tube 20 is positioned so that its distal end is located near the site where the vein wall 70 is punctured. Also shown is the guidewire 42 used to guide the main tube 20 to this target location within the coronary vein 72. The manipulating wire 40 is in a relaxed state, and the distal end of the main tube 20 is in a straight shape.

[0036] In Figure 10, the guidewire 42 (not shown) has been withdrawn from the first lumen 26 (not shown) and replaced by the insertion of the puncture device 44 into the main tube 20 through the same first lumen 26. To perform the puncture procedure, the manipulator wire 40 is pulled back posteriorly (proximal) under tension. Since the distal end of the manipulator wire 40 is attached to the main tube 20 at the side hole 22, pulling the manipulator wire 40 posteriorly in this manner causes the main tube 20 to bend at the flexible segment 34. Due to this bending of the main tube 20, the distal end of the main tube 20 faces a more angular direction toward the vein wall 70. As a result of this bending of the main tube 20, the puncture device 44 is advanced with the force necessary to puncture through the vein wall 70 into the myocardium 74. Note that this advancement causes the flexible segment 34 to press against the opposing wall 70, resulting in bulging of the opposing wall 70 of the coronary vein 72.

[0037] In Figure 11, the manipulating wire 40 is further pulled back, increasing the tension. As a result of this pull back, the bendable portion 34 bends further so that the main tube 20 and the puncture device 44 are directed towards the myocardium 74 at a steeper angle. The puncture device 44 is advanced into the myocardium 74, creating an entry passage into the myocardium 74 toward the interventricular septum. This entry passage is used by the electrode leads that are later inserted.

[0038] Figure 12 shows the situation in Figure 11 in a cross-section of the heart, illustrating the overall insertion procedure of the catheter device 10. In this figure, the right ventricle 62 and left ventricle 60 are visible in the cross-section. To establish the insertion route, a guidewire (not shown here) is inserted into the coronary sinus 68 located in the right atrium of the heart. From the coronary sinus 68, the guidewire is advanced through the great cardiac vein. The catheter device 10 is fabricated to follow this route by inserting the proximal end of the guidewire into the first lumen of the main tube 20. The catheter device 10 is then advanced along the guidewire so that the main tube 20 is located inside the great cardiac vein 66. Thus, the catheter device 10 is inserted into the coronary sinus 68 and passes through the great cardiac vein 66. The catheter device 10 is advanced so that the distal end of the main tube 20 is positioned close to the interventricular septum (IVS) 64.

[0039] In this technique for the interventricular septum 64, the main tube 20 may pass through other coronary veins, such as septal veins. However, not all humans have septal veins, and the present invention does not require the presence of such veins. With the catheter device 10 positioned at the target site, the guidewire is then replaced with a puncture device 44. The flexible portion 34 of the main tube 20 is designed to bend. The puncture device 44 is advanced at an angle to puncture the cardiac vein 66 and penetrate into the myocardium toward the interventricular septum 64.

[0040] The lancing device 44 creates an entry passage into the myocardium to the interventricular septum 64. With this entry passage established, the lancing device 44 is replaced with an electrode lead or a circular wire (not shown here). In the case of an electrode lead, the electrode lead is advanced so that its electrode is positioned inside the interventricular septum 64. Thus, the electrode lead is implanted in the interventricular septum 64 and may be activated (for example, for cardiac pacing or ablation treatment).

[0041] Figure 13 shows how an external ultrasound probe 90 may be used by the operator to assist in guiding the puncture procedure. The ultrasound probe 90 emits sound waves 92 to image the distal end of the main duct 20. The puncture device 44 may also be visible in the ultrasound image. The C-shaped curved segment 88 of the main duct 20 is also shown here. This curved segment 88 adapts to the natural curved passage of the coronary sinus 68. This ensures that the main duct 20 is precisely oriented so that the curved segment 34 curves outward to direct the deflection angle toward the interventricular septum 64.

[0042] Figures 14 to 16 show how the bendable segment 34 of the main tube 20 is designed to bend when the manipulative wire 40 is pulled back. In Figure 14, the manipulative wire 40 has exited the main tube 20 through the proximal side hole 24 and is in a relaxed position (no tension applied). In Figure 15, the manipulative wire 40 is pulled back posteriorly (proximal) in the direction of arrow 96. Since the distal end of the manipulative wire 40 is attached to the main tube 20 through the distal side hole 22, pulling the manipulative wire 40 posteriorly in this way causes the main tube 20 to bend at the bendable section 34. In Figure 16, the manipulative wire 40 is pulled back further, increasing the tension. As a result of this pull back, the bendable section 34 bends further, orienting the main tube 20 and the puncture device 44 at a steeper angle.

[0043] Figure 17 shows an example of a cardiac pacemaker device 100 that can be implanted using a catheter device 10. The pacemaker device 100 comprises an electrical pulse generator 104 and electrode leads. The electrode leads are equipped with a lead wire 102 and an electrode 110 at the distal end. The distal end also has a ring cap 106 and a claw 108 for fixation within the myocardium.

[0044] Figures 18A and 18B show other examples of the catheter device 120 of the present invention. Figure 18A shows the catheter device 120 comprising a handle assembly 130, a conical hood 132, and a port 134 on the underside for inserting a puncture device. Also shown is a flexible main tube 122 having a pre-formed C-shaped curved segment 124 and a bendable segment 126. Figure 18B shows a detailed view of the distal end of the main tube 122. The pre-formed C-shaped curved segment 124 is shown, defined by points A and B as described above. The dashed line 138 represents the length of the C-shaped curved segment 124 (i.e., the distance from point A to point B when superimposed on the C-shaped curved segment 124). The distal end 128 of the main tube 122 has an exit hole 136 from which a puncture device (not shown) can be withdrawn.

[0045] Figure 19 shows another example of how the distal portion of a flexible main tube 140 may be shaped. Here, the main tube 140 has a V-shaped curve 142 instead of a C-shaped curve. This V-shaped curve has a vertex 144. This V-shaped curve 142 may be defined by the same dimensional measurements as those described above for the C-shaped curve. The distal tip 148 of the main tube 140 and the exit hole 146 from which a puncture device (not shown) exits are also shown.

[0046] [experiment] A prototype of the experimental catheter device was tested in 10 pig animals. The sheath was inserted into an entry vein (jugular vein, subclavian vein, or femoral vein) and the procedure was performed. A first guidewire was inserted through this sheath and moved into the coronary sinus. Along this guidewire path, the balloon-tipped guide catheter was introduced into the heart and coronary sinus. The balloon was engaged with the coronary sinus to form a seal, and a radiopaque contrast agent was injected under pressure to obtain a radiofluoroscopic image (i.e., pressurized venography). This pressurized venography was used to confirm whether or not a septal vein was present in the vibrating animal.

[0047] The first guidewire was replaced with a thinner second guidewire for introducing the experimental catheter device. This thinner guidewire was advanced into the great cardiac vein. The catheter device was introduced into the great cardiac vein along this guidewire and positioned in a suitable location and vector direction for engagement with the septal myocardium. At this time, the distal end of the catheter device was bent at an angle toward the septal myocardium.

[0048] The second guidewire was replaced with a third, more rigid guidewire to function as a puncture wire. The puncture wire was pushed forward to directly puncture the wall of the great cardiac vein and enter the myocardium toward the septum. The amount of force required to push the puncture wire through the vein wall into the myocardium was measured using a push-pull gauge. A force of 0.45 N (Newtons) was required to penetrate the vein wall. Inside the myocardium, a smaller force of 0.04 N was required to push through the myocardial tissue.

[0049] Using fluoroscopy guidance, the puncture wire was further advanced to the target site within the interventricular septum. Echocardiography and fluoroscopy confirmed that the puncture wire was in the desired position. This puncture procedure was successfully performed on all 10 pig animals.

[0050] After the procedure experiment was completed, the heart was removed for visual pathological and histopathological examination. Visual examination revealed no significant tissue damage to the blood vessels or myocardial wall. A hematoma was present around the puncture site, but there was no spread of the hematoma to other areas or serious damage. There was no bleeding in the epicardium where the guidewire entered the myocardium. Microscopic histopathological examination revealed no myocardial damage. Several hemorrhagic foci were found in the myocardium and epicardium. However, there was no ischemic damage or necrosis.

[0051] The descriptions and examples provided herein are intended to illustrate, and not limit, the present invention. Each of the disclosed aspects and embodiments of the present invention may be considered individually or in combination with other aspects, embodiments, and variations of the present invention. In addition, unless otherwise specified, the steps of the method of the present invention are not limited to any particular order of execution. Modifications of the disclosed embodiments incorporating the spirit and essence of the present invention may be conceived by those skilled in the art, and such modifications are within the scope of the present invention.

[0052] Any use of the word "or" in this specification is intended to be inclusive and equivalent to the expression "and / or" unless the context clearly indicates otherwise. Therefore, for example, the expression "A or B" means A, or B, or both A and B. Similarly, for example, the expression "A, B, or C" means A, or B, or C, or any combination thereof. This specification contains the following provisions: [Clause 1] A method for creating a transvenous access route within the interventricular septum of a patient's heart, A step of obtaining a catheter device having a main tube, wherein the main tube comprises a distal end segment, a distal tip, and a lumen, and the catheter device further comprises a puncture device that passes through the lumen. The steps include inserting the main tube into the inlet vein, The steps include advancing the catheter device so that the main tube enters the coronary sinus and is positioned at a target site inside the coronary vein, The steps include bending the distal end segment of the main vessel so that its distal tip is angled toward the wall of the coronary vein, The steps include pushing the puncture device out of the main vessel to puncture the wall of the coronary vein, A method comprising the steps of advancing the puncture instrument through the myocardium toward the interventricular septum to create an entrance passage to the interventricular septum. [Clause 2] The catheter device further comprises an operating wire fixed to the distal end segment of the main tube, The method according to Clause 1, wherein the step of bending the distal end segment of the main pipe includes pushing or pulling the operating wire. [Clause 3] The method according to Clause 2, wherein the operating wire is fixed within 1.0 cm from the distal end of the main tube. [Clause 4] The catheter device further comprises a handle assembly equipped with an operating actuator, The method according to Clause 2, wherein the operating wire is coupled to an operating actuator that works to push or pull the operating wire. [Clause 5] The method according to Clause 4, wherein the lumen is a first lumen for the puncture device, the main tube further comprises a second lumen separate from the first lumen, and the operating wire passes through the separate second lumen of the main tube. [Clause 6] The method according to clause 4, wherein the main tube has an exit hole from the second lumen, and the operating wire exits the second lumen through the exit hole. [Clause 7] The operating actuator comprises a slider, the operating wire is fixed to the slider, and the method is The method according to clause 4, further comprising the step of moving the slider back and forth to push or pull the operating wire. [Clause 8] The method according to Clause 1, wherein the angle of the bend is at least 45° with respect to the longitudinal axis of the main pipe. [Clause 9] The distal end segment of the main tube comprises three or more radiopaque markers, and the method is The method according to Clause 1, further comprising the step of observing the arrangement of the radiopaque markers under X-ray fluoroscopy to determine the amount of curvature at the distal end segment of the main tube. [Clause 10] The method according to Clause 1, further comprising the step of applying a force of 0.205 to 1.25 N (Newtons) to the puncture instrument when advancing the puncture instrument through the vein wall. [Clause 11] The method according to clause 10, wherein the coronary vein is the great cardiac vein. [Article 12] The method according to Clause 1, further comprising the step of the method applying a force of less than 0.20 N (Newtons) when advancing the puncture instrument through the vein wall, wherein the coronary vein is a septal vein. [Clause 13] The method according to Clause 1, further comprising the step of performing pressurized venography of the coronary veins. [Clause 14] The method according to Clause 1, wherein the main vessel further comprises a pre-formed C-shaped curved segment, the C-shaped curved segment following the natural curvature of the coronary sinus. [Article 15] The method according to Clause 1, wherein the main tube is provided with a coil element at the distal end segment, and the bending occurs at the coil element. [Clause 16] The aforementioned entry path is for positioning the electrode lead inside the interventricular septum, and the method is The steps include withdrawing the puncture device from the catheter device, The step of inserting the electrode lead through the lumen so that the electrode lead enters the coronary sinus and passes through the coronary vein, The method according to Clause 1, further comprising the step of advancing the electrode lead through the puncture hole in the vein wall into the entrance passage of the interventricular septum. [Article 17] The method according to Clause 16, wherein the electrode lead is a pacing lead, and the method further comprises the step of activating a pacing stimulus to induce pacing of the heart. [Clause 18] The method according to Clause 16, wherein the electrode lead is a radiofrequency ablation lead, and the method further operates the electrode to ablate cardiac tissue. [Article 19] The aforementioned access route is for a mitral valve loop circulage wire when performing mitral valve circulage surgery, and the method is The steps include withdrawing the puncture device from the catheter device, The steps include inserting the circular wire through the lumen so that the circular wire enters the coronary sinus and passes through the coronary vein, The method according to Clause 1, further comprising the step of advancing the circular wire through the puncture hole in the vein wall into the entrance passage of the interventricular septum. [Clause 20] The method according to Clause 1, further comprising the step of using the opposing wall of the coronary vein as a support wall for applying pressure to the puncture device. [Article 21] A main tube comprising a distal end segment, a distal tip, a lumen, and an outlet hole exiting the lumen, wherein the main tube comprises a pre-formed C-shaped curved segment extending from a proximal point A to a distal point B, where point A is located within a distance of 6.0 to 15 cm from the distal tip of the main tube, point B is located within a distance of 0.4 to 4.0 cm from the distal tip of the main tube, point B is located distal to point A, and the length of the C-shaped curved segment from point A to point B is within a length range of 5 to 20 cm. An operating wire that passes through the lumen and is fixed to the distal end segment of the main tube at a point within 1.0 cm from the distal end of the main tube, wherein the operating wire exits the lumen through the outlet hole of the main tube, A catheter device comprising: a handle body equipped with an operating actuator, wherein the operating wire is coupled to the operating actuator which acts to push or pull the operating wire; and a catheter device. [Article 22] The catheter apparatus according to Clause 21, wherein the operating actuator comprises a slider and the operating wire is fixed to the slider. [Article 23] A septal puncture assembly comprising a catheter device as described in Clause 21, wherein the lumen is a first lumen, the main tube further comprises a second lumen, and the septal puncture assembly further comprises a puncture device that passes through the second lumen.

Claims

[Claim 1] A method for creating a transvenous access route within the interventricular septum of a patient's heart, A step of obtaining a catheter device having a main tube, wherein the main tube comprises a distal end segment, a distal tip, and a lumen, and the catheter device further comprises a puncture device that passes through the lumen. The steps include inserting the main tube into the inlet vein, The steps include advancing the catheter device so that the main tube enters the coronary sinus and is positioned at a target site inside the coronary vein, The steps include bending the distal end segment of the main vessel so that its distal tip is angled toward the wall of the coronary vein, The steps include pushing the puncture device out of the main vessel to puncture the wall of the coronary vein, A method comprising the steps of advancing the puncture instrument through the myocardium toward the interventricular septum to create an entrance passage to the interventricular septum.

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