Electrophysiological devices with deflection detection

Abstract

To provide a guiding sheath assembly.SOLUTION: A guiding sheath assembly has an elongated shaft, a control handle with a control knob, and a shuttle configured for translation in response to manipulation of the control knob. The assembly includes a puller wire extending along the shaft and responsive to translation of the shuttle to deflect the shaft. The puller wire has a stop at its proximal end, where a deflection sensor is affixed to stop a subject to compression to generate a signal in response to distortion between the first shuttle and the first stop. A catheter having a control handle and a control knob for manipulation of a deflection puller wire whose proximal end is affixed to a stop anchored in the control handle housing includes a strain gauge affixed to the stop configured to detect deformation resulting from actuation of the puller wire in deflecting the catheter shaft. A drip chamber is also provided.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a guide sheath particularly suitable for guiding an electrophysiological catheter, specifically a deflectable guide sheath.

Background Art

[0002] Guide sheaths and electrophysiology (EP) catheters are well known for use in the diagnosis and / or treatment of various cardiovascular conditions, including atrial fibrillation and other abnormal heart rates known as arrhythmias. In human cardiac catheterization, it is often necessary to reach the heart cavity through the femoral vein and aorta with an elongated EP probe. To vary the movement of such devices, guide sheaths, catheters, etc. can be maneuverable or deflectable by the use of one or more pull wires for operability within the patient's vasculature. The control handle is appropriately operated by the operator to deflect these EP tools while they are within the patient's vasculature and heart, but the occurrence and degree of deflection can sometimes be difficult to evaluate from moment to moment.

[0003] In ablation catheters, irrigation of the ablation tissue site provides multiple advantages, including cooling the ablated tissue and creating deeper and larger lesions. A flush fluid, such as saline, is typically delivered to the ablation site by luminal tubing that passes the fluid through an IV bag and drip chamber remote from the EP device, through the control handle and shaft of the EP device, and into a luer hub connected to the flush tubing. Thus, fluid from the IV bag typically drips into the drip chamber, and when the IV bag is depleted and the reservoir of the drip chamber is empty, there is a risk that air in the drip chamber will enter the luminal tubing, the flush tubing of the EP device, and further into the patient's vasculature where the misintroduction of air can be fatal.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Therefore, a guide sheath or catheter that can provide indication of the occurrence and direction of deflection, as well as whether the deflection curve is taut or relaxed, and a drip chamber that automatically closes the outlet of the drip chamber when the IV bag is depleted are desired. [Means for solving the problem]

[0005] In some embodiments, a guide sheath assembly comprises an elongated shaft and a control handle. The control handle has a longitudinal axis and a control knob and includes a first shuttle configured to translate along the longitudinal axis in one direction in response to one operation of the control knob, and a second shuttle configured to translate along the longitudinal axis in a different direction opposite to the first direction in response to another operation of the control knob. A first puller wire extends to one side of the shaft and deflects the shaft toward the one side in response to the translational motion of the first shuttle, and the first puller wire has a first stopper at its proximal end. A second puller wire extends to the other side of the shaft and deflects the shaft toward the other side in response to the translational motion of the second shuttle, and the second puller wire has a second stopper at its proximal end. The assembly further includes a first deflection sensor configured to generate a first signal in response to compression between a first shuttle and a first stopper.

[0006] In some embodiments, the guide sheath assembly further includes a second deflection sensor located between a second shuttle and a second stopper, configured to generate a second signal in response to compression between the second shuttle and the second stopper.

[0007] In some embodiments, the first deflection sensor includes a piezoelectric pressure sensor.

[0008] In some embodiments, the first signal includes a voltage signal.

[0009] In some embodiments, the guide sheath assembly includes an elongated shaft and a control handle. The control handle includes a rotary shaft having a longitudinal axis and configured to rotate about the longitudinal axis of the control handle; a first shuttle having a first plurality of teeth, configured to translate in one direction along the longitudinal axis in response to the rotation of the rotary shaft; a pinion mating with the first plurality of teeth, configured to rotate about an axis substantially perpendicular to the longitudinal axis in response to the translational motion of the first shuttle; and a second shuttle having a second plurality of teeth mating with the pinion, configured to translate along the longitudinal axis in the other direction opposite to the first direction in response to the rotation of the pinion. The assembly also includes: a first puller wire extending to one side of the shaft and having a proximal portion that responds to the translational motion of a first shuttle in the proximal direction, and having a first stopper at its proximal end; a second puller wire extending to the other side of the shaft and having a proximal portion that responds to the translational motion of a second shuttle in the proximal direction, and having a second stopper at its proximal end; and a first deflection sensor located between the first shuttle and the first stopper and configured to generate a first signal in response to compression when the first shuttle is actuated to deflect an elongated shaft in one direction.

[0010] In some embodiments, the guide sheath assembly further includes a second deflection sensor located between a second shuttle and a second stopper, configured to generate a second signal in response to compression of a second locking element when the second shuttle is actuated and deflects the elongated shaft in the other direction.

[0011] In some embodiments, the first deflection sensor includes a piezoelectric pressure sensor.

[0012] In some embodiments, the first signal includes a voltage signal.

[0013] In some embodiments, the electrophysiological system includes a guide sheath assembly and a control device. The assembly includes an elongated shaft, a control handle located proximal to the shaft and having a longitudinal axis and a deflection control knob, and including a shuttle configured to translate along the longitudinal axis in response to operation of the control knob, a puller wire extending along the shaft and responding to the translational motion of the shuttle to deflect the elongated shaft, and having a stopper at its proximal end, and a deflection sensor configured to generate a signal in response to compression between the shuttle and the stopper when the elongated shaft is deflected. The control device includes a processor configured to receive the signal, measure a voltage from the signal, and determine the occurrence of deflection based on the measured voltage.

[0014] In some embodiments, the processor is further configured to perform an operation to determine the degree of deflection based on the measured voltage.

[0015] In some embodiments, the console includes a memory configured to store an index that correlates a given voltage with a given degree of deflection, and the processor is further configured to access the index to determine the degree of deflection based on the measured voltage.

[0016] In some embodiments, the deflection sensor includes a piezoelectric pressure sensor.

[0017] In some embodiments, the system includes an indicator mechanism configured to provide a user with a signal indicating the occurrence of a deflection in response to a control device and based on a measured voltage.

[0018] In some embodiments, the indicator mechanism is configured to provide a visual signal.

[0019] In some embodiments, the instruction mechanism is configured to provide an audible signal.

[0020] In some embodiments, the electrophysiological catheter comprises an elongated shaft and a control handle located proximal to the shaft, having a longitudinal axis and a control knob. The catheter further includes a puller wire extending through the shaft and having a proximal end, a rocker responsive to the control knob to deflect the elongated shaft, having a pulley member around which the puller wire extends, a stopper fixed to the proximal end and attached to the control handle, and a strain gauge fixed to the stopper and configured to generate a signal in response to strain on the stopper.

[0021] In some embodiments, the control handle also includes a second puller wire extending through the opposite side of the shaft and having a second proximal end, and the rocker has a second pulley member through which the second puller wire extends. The control handle also includes a second stopper fixed to the second proximal end and attached to the control handle, and a second strain gauge fixed to the second stopper and configured to generate a second signal in response to strain in the second stopper.

[0022] In some embodiments, the signal includes a voltage signal.

[0023] In some embodiments, the electrophysiological catheter includes an elongated shaft and a control handle. The control handle further includes a rocker having a pulley member, having a longitudinal axis and a control knob, and a rocker that deflects the elongated shaft in response to the control knob; a tension member having a distal portion extending through the shaft and a proximal portion extending around the pulley member; a connector extending between the distal and proximal portions of the tension member; and a strain gauge fixed to the connector and configured to generate a signal in response to strain in the connector.

[0024] In some embodiments, the dropping chamber includes a hollow housing defining a chamber communicating with an inlet and an outlet, a bag spike at the inlet, an outlet nozzle located on the distal side of the outlet, and a spherical plug configured to float within the chamber when liquid is present within the chamber and fall under gravity into the outlet nozzle to provide a fluid-tight seal within the outlet nozzle when the chamber is liquid-free.

[0025] In some embodiments, the dropping chamber includes a hollow housing defining a chamber communicating with an inlet and a tapered outlet, a bag spike at the inlet, an outlet nozzle located on the distal side of the tapered outlet, and a plug having an upper wide portion, an intermediate tapered portion, and a lower tapered portion, the plug being configured to float within the chamber when liquid is present within the chamber and fall under gravity into the chamber when the chamber is liquid-free, wherein the intermediate tapered portion seats in the tapered outlet and the lower tapered portion seats within the outlet nozzle to provide a fluid-tight seal by the outlet nozzle.

[0026] In some embodiments, the intermediate tapered portion has a larger taper portion, and the tapered outlet has a smaller taper portion such that a space gap exists between the intermediate tapered portion and the tapered outlet.

Brief Description of the Drawings

[0027] These features and advantages of the present invention, as well as other features and advantages, will be more fully understood by considering the following detailed description in conjunction with the accompanying drawings. It should be understood that in some of the specific drawings, certain selected structures and mechanisms are not shown in order to make the remaining structures and mechanisms more visible. [Figure 1] FIG. 1 is a plan view of a guide sheath including a control handle according to an embodiment. [Figure 2] FIG. 2 is a longitudinal sectional view of the control handle of FIG. 1. [Figure 3] FIG. 3 is an exploded view of the control handle of FIG. 1 with the housing removed. [Figure 4]This is a longitudinal cross-sectional view of the distal portion of the control handle in Figure 1, including the control knob. [Figure 5] Figure 1 is a perspective view of the control handle with the housing removed. [Figure 6A] This is a plan view of a neutral indicator mechanism according to one embodiment, showing the first member and the second member fitted together. [Figure 6B] Figure 6A is a plan view of the neutral indicator mechanism in a state where the first member and the second member are engaged and disengaged. [Figure 7A] This is a plan view of the interior of a bidirectional guide sheath control handle equipped with first and second shuttle members and a deflection sensor, according to one embodiment. [Figure 7B] This is a plan view of the interior of a bidirectional guide sheath control handle equipped with first and second shuttle members and a deflection sensor, according to one embodiment. [Figure 8A] These are detailed side views of the deflection sensor shown in Figures 7A and 7B, which is located between the shuttle member and the stopper. [Figure 8B] These are detailed side views of the deflection sensor shown in Figures 7A and 7B, which is located between the shuttle member and the stopper. [Figure 9] This is a diagram of an EP system, according to one embodiment, which includes an EP device (e.g., a guide sheath or catheter) and a console, used on a patient when operated by an operator. [Figure 10] This is a plan view of the inside of a bidirectional control handle of an EP catheter according to one embodiment. [Figure 11A] These are simplified diagrams of the control handle in Figure 10, showing the neutral position, deflected in one direction, and deflected in another direction, respectively. [Figure 11B] These are simplified diagrams of the control handle in Figure 10, showing the neutral position, deflected in one direction, and deflected in another direction, respectively. [Figure 11C] These are simplified diagrams of the control handle in Figure 10, showing the neutral position, deflected in one direction, and deflected in another direction, respectively. [Figure 12]This is a detailed plan view of a strain gauge on a tension member connector according to one embodiment. [Figure 13] This is a side cross-sectional view of a control handle according to one embodiment. [Figure 14A] This is a side cross-sectional view of a dropping chamber according to one embodiment. [Figure 14B] This is a side cross-sectional view of a dropping chamber according to one embodiment. [Figure 15A] This is a detailed side view of a dropping chamber according to another embodiment. [Figure 15B] Figure 15A is a side view of the plug. [Figure 15C] Figure 15A is a detailed view of the spatial gap between the plug and the side wall of the dripping chamber. [Modes for carrying out the invention]

[0028] Referring to Figure 1, in some embodiments of the present invention, the guide sheath assembly 10 includes an elongated flexible sheath 12 and a control handle 16 located proximal to the sheath 12. The sheath 12 includes a proximal section 13 and a distal deflection section 14. The control handle 16 can be connected to an electrical connector 17 for transmitting electrical signals sensed by one or more ring electrodes 19 supported on the sheath 12, for example, including the deflection section 14. As shown in Figure 1, the control handle 16 is also fitted with a hemostatic valve 18 configured to receive a catheter (not shown) that can be advanced through the central lumen 22 of the guide sheath assembly 10 (modified Figure 1). The hemostatic valve 18 also has a side port 21 terminating with a Luer hub, such as a two-way stopcock 23, for connecting to one or more fluid sources (not shown) to supply fluid through the lumen 22 into the lumen 22 of the guide sheath assembly 10.

[0029] As shown in Figures 2 and 3, the control handle 16 includes an elongated, substantially cylindrical body 24 having a narrower distal portion, i.e., a shaft portion 25, to which a distal rotation control knob 26 is attached. The body 24 has an outer shell half-member formed to define an internal volume V, the edges 51 of which are joined together along a longitudinal seam. The distal shaft portion 25 of the body has an outer diameter D1 smaller than the outer diameter D2 of the proximal portion of the body 24. The control knob 26 is configured to be rotated by the user's thumb and index finger when the user grips the body 24 of the control handle 16. To allow deflection of the deflection section 14 of the guide sheath 12 by the first and second puller wires 30A and 30B, the control handle 16 includes a rotary shaft 31, first and second shuttles 32A and 32B, and a pinion 34 within its internal volume V. The rotary shaft 31 drives the first shuttle 32A in response to the control knob 26, moving it linearly in a first direction along the longitudinal axis 55, and the pinion 34 connects the second shuttle 32B to the first shuttle 32A, so that the second shuttle 32B moves linearly in a second direction opposite to the first direction along the longitudinal axis. Since the proximal ends of the first and second puller wires 30A and 30B are attached to or at least connected to the first and second shuttles 32A and 32B, respectively, the connected translational motion of the first and second shuttles in opposite directions acts on the first and second puller wires to cause the deflection section 14 of the guide sheath 12 to deflect in two directions.

[0030] The rotary shaft 31 has a main proximal portion 36 having an outer diameter D3, a shorter distal portion 37 having an outer diameter D4, and a stepped connection J between sections 36 and 37. In the embodiment shown in the figure, diameter D3 is larger than diameter D4, but it will be understood that the two diameters may be approximately equal, or diameter D4 may be larger than diameter D3. As is clearly shown in Figure 2, the rotary shaft 31 is positioned relative to the body 24 of the control handle 16 such that its proximal section 36 passes through both the body 24 and the distal shaft portion 25 of the control handle 16 and extends beyond the distal end of the distal shaft portion 25, and the connection J and the distal section 37 are located distal to the distal shaft portion 25 of the body 24 so that the distal section 37 is not surrounded by the distal shaft portion 25. The rotary shaft 31 is connected to and fixed to the main body 24 at its proximal end by a proximal outer circumferential lip 38 that fits into an inner circumferential slot defined between circumferential flanges 40 formed within the internal volume V of the main body 24.

[0031] Referring to Figure 4, the rotary shaft 31 is hollow and has an internal passage 42. The passage 42 communicates with a distal inlet 44, which has a diameter slightly larger than the diameter of the guide sheath 12. The passage 42 is spiral and has a diameter such that it accommodates both the guide sheath 12 and the shuttles 32A and 32B that surround the guide sheath 12 in the circumferential direction, as will be discussed in more detail below.

[0032] The control knob 26 is attached to the distal shaft portion 25 and the rotary shaft 31 of the body 24 of the control handle 16, and has a main proximal portion 46 and a short distal end portion 47. The control knob 26 is substantially cylindrical in shape, having a longitudinal hollow interior that extends along its entire length. The hollow interior has a main proximal section 49, an intermediate portion 49', and a distal section 49''. The main proximal section 49 of the hollow interior houses the guide sheath 12 and shuttles 32A and 32B, surrounding them circumferentially, and is defined by a larger first radius R1 and a larger first length L1. The distal section 49'' of the hollow interior houses the guide sheath 12 and the distal section 37 of the rotary shaft 31, surrounding them, and is defined by a smaller second radius R2 (R1>R2) and a smaller second length L2 (L1>L2). The hollow interior intermediate section 49' houses the connection point J between the guide sheath 12 and the rotary shaft 31, and is defined by a third radius R3 (R1>R3>R2) and a third length L3 (L1>L3) that surrounds it. A friction-generating cover 60 can be attached to the outer surface of the control knob 26 to allow the user to easily and comfortably operate the control knob and rotate it relative to the body 24 of the control handle 16.

[0033] To rotatably connect the rotary shaft 31 to the control knob 26, the outer surface of the distal section of the shaft has a longitudinal ridge 70 (Figure 3), which is received into a corresponding longitudinal recess 71 (Figure 4) formed on the inner surface defining the hollow interior 49'' of the control knob 26, and is designed to fit into the recess 71. To fix the control knob 26 so as to be able to move translationally to the rotary shaft 31 and, consequently, to the main body 24, the outer surface of the shaft 31 further has one or more linear slots 74 oriented perpendicular to the longitudinal axis of the rotary shaft 31. By aligning each slot 74 with the respective holes 76 (Figure 5) formed through the side surface of the distal end portion 47 of the control knob 26, the respective pins 77 can be inserted into the holes 76 and slots 74 to connect the control knob 26 and the rotary shaft 31.

[0034] It will be understood that other embodiments of the guide sheath assembly may also provide a rotary shaft 31 having a portion exposed for direct operation by the user without the use of a control knob 26.

[0035] As shown in Figures 3 and 5, shuttles 32A and 32B have similar structures and are understood to be approximately mirror images of each other. The first shuttle 32A is driven by a rotary shaft 31, and the second shuttle 32B is driven by the first shuttle 32A via a pinion 34 located between the shuttles. Each shuttle 32A and 32B has an elongated body with distal portions 80A and 80B having a C-shaped end cross-section, and proximal rack portions 90A and 90B with multiple teeth 92A and 92B arranged longitudinally. The first and second shuttles are arranged opposite each other and fitted to the pinion 34, so that the distal portions 80A and 80BC together can form a cylindrical shape having an outer surface that fits into the screw passage 42 and an inner surface that defines a passage 93 through which the guide sheath 12 passes. As shown in Figure 5, the rack portions 90A and 90B of each shuttle face each other with the pinion 34 in between, and as a result, the teeth 92A and 92B of each rack portion can engage with the teeth of the pinion 34, which is mounted to rotate about an axis perpendicular to the longitudinal axis 55 of the control handle 16.

[0036] Referring to Figures 2 and 3, the outer surface of the distal portion 80A of the first shuttle 32A is provided with an outer or male threaded surface 85. The inner circumferential surface of the rotary shaft 31 is provided with an inner or female threaded surface 86 that receives the male threaded surface 85 of the first shuttle 32A (Figure 4), thereby connecting the first shuttle 32A and the rotary shaft 31, and converting the rotational motion of the rotary shaft 31 into the translational motion of the first shuttle 32A. In contrast, the outer surface of the distal portion 80B of the second shuttle 32B is smooth and has no features that allow it to engage with the female threaded surface of the rotary shaft, and as a result it can move independently of the male threaded surface 85. Therefore, when the user rotates the control knob 26 in the first direction, the rotary shaft 31, which is rotatably connected to the control knob 26 via the longitudinal protrusion 70, also rotates. The rotary shaft 31 is rotatably and translatably locked to the control knob 26 via a longitudinal protrusion 70 and one or more pins 77. Rotation of the shaft 31 drives the first shuttle 32A to translate along the longitudinal axis in a first direction (e.g., proximal direction). When the first shuttle 32A translates, its teeth 92A drive the pinion 34 to rotate in a first direction (e.g., clockwise), and the pinion 34 drives the second shuttle 32B to translate along the longitudinal axis 55 in a second direction opposite to the first direction (e.g., distal direction). In this arrangement, the male threaded surface 85 and the female threaded surface 86 convert the rotational motion of the control knob 26 into linear motion of the shuttles 32A and 32B. The proximal ends of the first and second puller wires 30A and 30B are fixed, connected to, or otherwise responsive to the first and second shuttles 32A and 32B, respectively, so that the linear and opposite motion of the shuttles acts on the puller wires to cause the deflection section 14 of the guide sheath 12 to deflect in two directions. In the embodiment shown in the figure, the proximal ends of the puller wires 30A and 30B are connected to the rack portions 90A and 90B of the shuttles 32A and 32B, respectively. This means that when one puller wire is pulled proximal under tension by its respective shuttle, the other puller wire is simultaneously released from tension by its respective shuttle moving distally.

[0037] As shown in Figure 2, the proximal ends of each puller wire 30A and 30B extend outside the sheath 12 within longitudinal grooves 88A and 88B formed in the proximal rack portions 90A and 90B of each shuttle 32A and 32B. As shown in Figure 5, stoppers 89A and 89B, such as hypotubes, are fixed to the proximal ends of each puller wire 30A and 30B, and these stoppers are positioned proximal to the proximal ends 87A and 87B of the respective rack portions 90A and 90B, so that when the shuttles 32A and 32B are moved proximal, the rack portions can push or otherwise act on the stoppers 89A and 89B, respectively, to pull the puller wires 30A and 30B proximal. When the shuttles are moved distally, the proximal ends of the rack portions disengage from the respective stoppers, and the puller wires are released from tension. It will be understood that stoppers 89A and 89B may also be embedded in the rack portion or any part of the shuttle, or otherwise secured, to deflect the sheath.

[0038] Since the first shuttle 32A and the second shuttle 32B move in opposite directions along the longitudinal axis 55, the initial positioning of the shuttles relative to each other and to the passage 42 is performed during the assembly of the control handle. For example, as shown in Figure 2, each shuttle is positioned within the passage 42 of the rotary shaft 31 so that they are aligned with each other along the longitudinal axis 55, and each has a distal end positioned approximately midway along the passage 42 so that each shuttle has sufficient space to move in the proximal or distal direction within the rotary shaft 31. If the guide sheath is nearly neutral with little deflection, the stoppers 89A and 89B can be positioned relative to the shuttles such that the tension on each puller wire 30A and 30B is minimal or uniform. In such an arrangement, the shuttles take a “neutral” initial form, that is, from which the user can uniformly deflect the guide sheath in two directions.

[0039] As shown in Figure 5, the pinion 34 is positioned between and relative to shuttles 32A and 32B so that the shuttle teeth 92A and 92B remain engaged while the shuttle translates in response to the user's operation of the control knob 26. In this regard, the lengths of the rack portions 90A and 90B are sufficient to ensure such continuous engagement.

[0040] For example, it will be understood that by changing one or more factors such as the length of the passage 42, the lengths of the distal sections 80A and 80B, the lengths of the rack sections 90A and 90B, the position of the pinion 34, and the number of pinions, different shuttle motion and deflection characteristics and limitations can be achieved as needed or desired.

[0041] Referring to Figures 6A and 6B, a neutral indicator mechanism is provided on the outer surfaces of each rack portion 90A and 90B opposite the teeth 92A and 92B of each shuttle 32A and 32B. The neutral indicator mechanism includes a first member 62A and a second member 62B configured to releasably fit together to indicate a neutral position between the first shuttle 32A and the second shuttle 32B, i.e., a relative position where the puller wires 30A and 30B are neutral and thereby the guide sheath 12 is nearly straight without deflection. In the embodiment shown in the figure, the first male member 62A formed on the first shuttle 32A has a tapered projection 63 facing the second female member 62B formed on the second shuttle 32B, the second member 62B includes a pair of flexible guide rails 64 on both sides, the fixed ends 65 of the guide rails 64 being fixed to the second shuttle 32B, and the free ends 66 of the guide rails 64 are configured to both form tapered recesses 67 in which the tapered projection 63 fits when the shuttles 32A and 32B are in a neutral position.

[0042] Therefore, the user is generally initially given the guide sheath 12 in an unbiased state, in which the first shuttle 32A and the second shuttle 32B are aligned with respect to each other, with the tapered projection 63 residing within the tapered recess 67, as shown in Figure 6A. When the user rotates the control knob 26 in one direction, as shown in Figure 6B, to drive the first shuttle 32A and the second shuttle 32B to translate in opposite directions, the tapered projection 63 disengages from the tapered recess 67 and moves out of the tapered recess 67. However, to achieve this, the user must rotate the control knob with sufficient force to flex the guide rail 64 and overcome the resistance provided by its angled end 68. The guide rail 64 is inclined such that, as the tapered projection 63 passes over one of the angled ends 68, the resistance to the movement of the tapered projection 63 decreases as it moves further away from the tapered recess 67. Therefore, when rotating the control knob 26 to deflect the guide sheath 12, the user feels greater or maximum resistance when the shuttles 32A and 32B first start moving from the neutral position, and then gradually finds it easier to move as the shuttles 32A and 32B translate in opposite directions. The control handle 16 may have visual and / or tactile markings to give a constant orientation of the deflection direction. For example, clockwise rotation of the control knob 26 consistently deflects the shaft 12 sideways, i.e., towards the side port 21, and counterclockwise rotation of the control knob 26 deflects the shaft 12 to the opposite side or direction.

[0043] Conversely, to release the deflection of the guide sheath 12, the user rotates the control knob 26 in the opposite direction. As shuttles 32A and 32B move in translation and approach each other, and begin to align laterally again, the tapered projection 63 and the tapered recess 67 approach each other, and the user applies greater force to rotate the control knob 26 so that the tapered projection 63 crosses over the angled end 68 of the guide rail 64 again before the tapered projection 63 can fit into the tapered recess 67. Thus, the increasing resistance provided by either of the inclined rails 64, and the greater or greatest resistance provided by the angled end 68, gives the user a tactile sensation or indication that the tapered projection 63 is approaching the tapered recess 67. The fitting of the tapered projection 63 and the tapered recess 67 can provide the user with an audible "click" sound or signal when the flexible guide rail 64 springs back to its natural shape after the load on the tapered projection 63 has been removed from the guide rail 64.

[0044] In some embodiments, as shown in Figures 7A and 7B, for example, a control handle 100 for a deflectable guide sheath includes stoppers 189A, 189B fixed to the proximal ends of puller wires 130A, 130B, respectively, the stoppers 189A, 189B being located proximal to the proximal ends 187A, 187B of shuttles 132A, 132B, such that selective movement of the shuttle by a user operating a control knob 126 acts on the stoppers 189A, 189B to deflect a flexible guide shaft (see, for example, 12 in Figure 1) located distal to the control handle 100, through which the puller wire extends. In this regard, each shuttle 132A, 132B has a corresponding deflection sensor 102A, 102B (shown by dashed lines) configured to detect the occurrence of deflection, if not the amount, range, or degree of deflection of the guide shaft.

[0045] In Figure 7A, the control knob 126 is operated by the user to translate the shuttle 132B distally (arrow B) while translating the shuttle 132A proximally (arrow A) (for example, by rotating it around the longitudinal axis 55). Specifically, the proximal end 187B presses against the stopper 189A, moving the stopper proximally, while the proximal end 187B releases the stopper 189B by moving it distally. Thus, the puller wire 130A is pulled taut proximally, deflecting the guide sheath toward the side of the control handle 126, and the puller wire 130B is moved freely distally to allow such deflection.

[0046] In Figure 7B, the control knob 126 is operated by the user to translate the shuttle 132B proximal (arrow B) while translating the shuttle 132A distal (arrow A) (for example, by rotating it around the longitudinal axis 55). Specifically, the proximal end 187B presses against the stopper 189B, moving the stopper proximal, while the proximal end 187A moves distally, releasing the stopper 189A. Thus, the puller wire 130B is pulled taut proximal, deflecting the guide sheath toward the side of the control handle 126, while the puller wire 130A can move freely distally to allow such deflection.

[0047] In some embodiments, each deflection sensor 102 includes a piezoelectric pressure sensor that responds to an applied pressure, generating a voltage proportional to the applied pressure, as will be understood by those skilled in the art. In the embodiments shown in Figures 8A and 8B, the piezoelectric pressure sensor includes a piezoelectric element 106 and a corresponding voltmeter circuit 107. The piezoelectric element may be, for example, a quartz crystal, and is positioned between the shuttle stopper 189 and the proximal end 187 such that the operation of the shuttle results in compression of the piezoelectric element 106. As will be understood by those skilled in the art, when a compressive force F (Figure 8A) is applied to the piezoelectric element, a charge is generated across the entire surface of the piezoelectric element 106. The charge can be measured as a voltage V in the circuit 107 that is proportional to the compressive force. Advantageously, no external voltage or current source is required. Each piezoelectric element 106 generates an output signal directly from the applied compressive pressure, which is measured by a voltmeter circuit including two leads 109, 110 per piezoelectric element.

[0048] In some embodiments, as shown in Figure 8A, the voltage V representing the amount of compressive force acting on the piezoelectric element 106 is measured longitudinally across the distal end D and proximal end P of each piezoelectric element 106, i.e., longitudinally across the piezoelectric element in a direction substantially parallel to the longitudinal axis A, since the compressive force applied to the piezoelectric element 106 between the stopper 189 and the proximal end 187 of the shuttle by the shuttle 132 is greatest in the direction of the longitudinal axis A. Thus, lead 109 is connected to the proximal end D of the piezoelectric element, and lead 110 is connected to the proximal end P of the piezoelectric element. As will be understood by those skilled in the art, leads 108 and 109 may extend further proximal through the control handle to another location, for example, to a remote signal processing location in an electrophysiological system 170 including a control device 180 with a processor 182 configured to process output signals from a deflection sensor, as shown in Figure 9. Piezoelectric pressure sensors are particularly sensitive to dynamic changes in compressive force and are therefore especially suitable for measuring small changes in compressive force.

[0049] In some embodiments, the degree of deflection or curvature of the guide shaft 112 located distal to the control handle 100, which is actuated by shuttles 132A, 132B in response to the user's operation of the control knob 126, is calibrated to different voltages generated by piezoelectric elements 106A, 106B in response to the amount of compressive force applied to the piezoelectric elements between each shuttle and stopper when the shaft 112 is deflected. Thus, when the catheter is used for patient treatment, an index correlating the measured voltage with the degree of deflection or curvature may be stored in the memory 184 of the processor 182 of the console 180 and provided to the user 186 with an output of the degree of deflection or curvature based on the input of the measured voltage derived from the voltmeter circuit of the deflection sensor. Generally, the higher the measured voltage V, the greater the compressive force, and therefore the greater the degree of deflection or curvature of the guide shaft in the selected direction. In some embodiments, the minimum voltage output by the deflection sensor is 0.0V, and the maximum voltage output is approximately 5.0V. In some embodiments, the maximum voltage output is approximately 10V. In some embodiments, the maximum voltage output is approximately 20V.

[0050] In some embodiments, the electrophysiological system 170 includes a display 188 configured to respond to a processor 182 in displaying a voltage indication mechanism or reading 191 to the user. In some embodiments, the system 170 includes one or more deflection indication mechanisms, e.g., LED 190a and speaker 190b, configured to be activated by a processor 58 when the voltage output of a deflection sensor exceeds a predetermined threshold representing the maximum deflection of the shaft 12 to avoid shaft breakage or damage, and to provide an audible and / or visual cue to the user. The deflection indication mechanisms may also be configured to provide identifiable audible and / or visual cues between left deflection, right deflection, and / or neutral (no deflection) in the guide shaft based on the identity of the deflection sensors 102A, 102B that generate the voltage output, or the absence of voltage output from the left and right deflection sensors. It will be understood that the processor may also be configured to detect the rate of change of the measured voltage when determining other aspects of deflection, such as whether the deflection curve is tightening or loosening.

[0051] The deflection sensor may be incorporated into any suitable control handle of an electrophysiological (EP) device having unidirectional or bidirectional deflection, which will be understood to include catheters and probes having elements within control handles that are movably connected or fitted to each other such that the elements are subjected to compressive or tensile forces on the deflection of the shaft. As shown in Figure 10, a suitable control handle 200 for use with an EP catheter or probe has a deflectable shaft 201 operated by a user operating a deflection control lever 202, the deflectable shaft 201 acts on rockers 203 that pull first and second tensile members 204A, 204B. A suitable control handle is disclosed in U.S. Patent No. 7,377,906, entitled “Steering Mechanism For Bi-Directional Catheter,” the entire disclosure of which is incorporated herein by reference. Each tension member includes a distal portion D (e.g., a puller wire) extending distally from the shaft 201, and a proximal portion P (e.g., a spun fiber such as VECTRAN®) wound around the respective pulleys 205A and 205B of the rocker 203, with the proximal ends, fixed to the respective stoppers 207A and 207B, being retained within the housing of the control handle. The distal portion D and proximal portion P of each tension member are connected by their respective connectors 208A and 208B, e.g., ferrules. As will be understood by those skilled in the art, when the user rotates the deflection control lever 202, the rocker 203 rotates with the lever, as shown in Figures 11A, 11B, and 11C, pulling one pulley proximally and moving the other pulley distally. The pulled pulley pulls the proximal portion P, which exerts a strain force on the ferrule 208A.

[0052] Strain gauges 210 mounted on the surface of each ferrule 208, as shown in Figure 12, detect deformation of the ferrule and cause a shift in electrical resistance in the strain gauge proportional to the strain applied to the surface. In some embodiments, the strain gauge 210 includes a winding pattern of etched metal wire 212 (e.g., copper-nickel alloy) on a substrate 214 (e.g., flexible polyimide film). As will be understood by those skilled in the art, the strain gauge changes its resistance by geometric change. Specifically, when the metal wire is subjected to tensile strain, the wire stretches elongated, and its cross-sectional area decreases, contributing to an increase in the wire's resistance. Similarly, when the wire is subjected to compressive strain, the wire shortens, and its cross-sectional area increases, contributing to a decrease in the wire's resistance. When bonded to the surface of the connector (e.g., the ferrule 208), the strain gauge 210 receives the strain force that the connector experiences when pulled by the pulley. The strain gauge is deflected and distorted to coincide with the surface of the connector, causing a shift in the electrical resistance of the strain gauge proportional to the strain applied to the surface. The strain is measured by a voltmeter circuit including leads 215 and 216, completing the voltmeter circuit. As will be understood by those skilled in the art, leads 215 and 216 may extend further proximal through a control handle to another location, for example, to a remote signal processing location in an electrophysiological system 170, which includes a console 180 equipped with a processor 182 configured to process the output signals from the deflection sensor by similar indexing of different outputs having different deflection curvatures, as described above.

[0053] Furthermore, it will be understood that the strain gauges 210 can be fixed to the surfaces of the stoppers 207A and 207B, respectively, to detect the deformation of the stoppers when the rocker arms are operated to deflect the catheter shaft.

[0054] The aforementioned deflection sensor may also be incorporated into a unidirectional control handle. A suitable unidirectional deflection control handle is described in U.S. Patent No. 6,602,242, entitled “Irrigated Tip Catheter,” the full text of which is incorporated herein by reference. The longitudinal movement of the puller wire 342 relative to the catheter body 312, resulting in deflection of the tip section (not shown), as shown in Figure 13, is achieved by suitable operation of the control handle 316. The distal end of the control handle 316 includes a piston 354 having a thumb control unit 356 for operating the puller wire 342. The proximal end of the catheter body 312 is connected to the piston 354 by a retractable sleeve 328.

[0055] The puller wire 342 and other components, such as lead wires, thermocouple wires, and the first injection tube segment 388, extend through the piston 354. The puller wire 342 is secured to an anchor pin 357 located near the piston 354. Within the control handle 16, the lead wires and thermocouple wires are housed in a protective sheath 339. Within the piston 354, the first injection tube segment 388 extends into another protective sheath 391, preferably made of polyurethane. The protective sheaths 339 and 391 are secured to the piston 354 at an adhesive joint 353, preferably by a polyurethane adhesive, allowing the first injection tube segment 388, lead wires, and thermocouple wires to move longitudinally within the control handle 316, and as a result, they do not break when the piston 354 is adjusted to operate the puller wire 342. Within the piston 354, the puller wire 342 extends through the transfer tube 327, preferably a polyimide tube, allowing longitudinal movement of the puller wire near the adhesive joint 353.

[0056] The piston 354 is located within the body 355 of the control handle. The body 355, which has a piston chamber for receiving the piston 354, is substantially solid. Extending proximal to the piston chamber are three longitudinal holes 358, 359, and 360, as well as a transverse hole for receiving the anchor pin 357. The second longitudinal hole 359 communicates with the transverse hole. The first injection tube segment 388 within the protective sheath 391 extends through the first longitudinal hole 358. The puller wire 342 extends through the second longitudinal hole 359 and is secured to the anchor pin 357 via the transverse hole. The thermocouple wire and lead wire within the protective sheath 339 extend through the third longitudinal hole 360. Between the distal ends of the longitudinal holes 358, 359, and 360 and the proximal end of the piston 354, the chamber 362 provides additional space to avoid undesirable bending of the first injection tube segment 388.

[0057] In some embodiments, the puller wire 342 includes a connector, a distal portion located within the body 355, and a proximal portion connected by, for example, a ferrule 208 in Figure 12, and the strain gauge 210 is positioned on the connector and subjected to the tensile force experienced by the ferrule 208 when pulled by the piston 354. In some embodiments, the strain gauge is attached to an anchor pin 357 to detect strain and deformation of the anchor to which the proximal end of the puller wire is attached.

[0058] One embodiment of a drip chamber 400 for use with an IV bag is shown in Figures 14A and 14B. The drip chamber 400 has a substantially cylindrical hollow housing 402 defining a chamber C that communicates with an inlet 404 and an outlet 406. The inlet 404 may consist of a bag spike 408 inserted into an IV bag, or may be configured to receive a bag spike cap 408C that covers and seals the inlet 404. The outlet 406 may consist of a tapered outlet nozzle 412 (which may be formed as a cap 412' that covers and seals the outlet 406). Those skilled in the art will understand that the outlet nozzle 412 may have an injection port at its distal end and is configured to connect to the proximal end of a tube 416 which may have either a needle or a Luer lock and adapter (not shown) at its distal end. Furthermore, after the bag spike 408 is inserted into the IV bag, it will be understood that under gravity, the fluid F from the IV bag will drip through the bag spike 408 into the chamber C, where the drips are collected in volume before the fluid F exits the chamber C through the outlet 406. The chamber C has an inner diameter DC. The outlet nozzle 412 has a tapered shape defined by a larger inner diameter D1 at the outlet 406 and a smaller inner diameter D2 located distal to the outlet.

[0059] In some embodiments, the drip chamber 400 includes a plug 418 that is buoyant or hollow and floats with the volume of fluid collected in the chamber C (Figure 14A), and whenever there is no fluid collected in the chamber C, falls into the outlet 406 under heavy gravity to block the outlet nozzle 412 (Figure 14B). In this regard, the shape and diameter of the plug 418 are configured to fit snugly into the outlet nozzle 412, and are, for example, spherical in shape with a diameter d defined as follows: DC>D1>d>D2 (Formula 1) During the ceremony, DC = Inner diameter of chamber C D1 = Inner diameter at outlet 406 D2 = Minimum diameter of outlet nozzle 412 d = Diameter of spherical plug 418

[0060] In some embodiments, the diameter d of the plug 418 is greater than the diameter D1 such that the plug remains approximately above or outside the outlet nozzle 412, and as a result, the plug can be more easily re-floated when the chamber is refilled.

[0061] Therefore, the plug 418 is configured to seat in the outlet nozzle 412, which seals the outlet nozzle when the chamber C is empty, preventing any air in the chamber from leaving the dripping chamber through the outlet nozzle. Whenever the fluid F refills the chamber C, the flotation plug 418 floats above the outlet nozzle 412, opening the outlet 406 so that the fluid can again exit the dripping chamber through the outlet nozzle. Thus, the flotation plug 418 is self-adjusting in response to the amount of fluid in the chamber, so as to float freely at the fluid level in the chamber C, allowing the fluid to exit through the outlet nozzle in the presence of fluid, and closing the outlet nozzle in the absence of fluid to prevent any airflow in the chamber from leaving the outlet nozzle.

[0062] In some embodiments, as shown in Figure 15A, a dropping chamber 430 having similar features to the dropping chamber 400 described above has a substantially cylindrical hollow housing 431, a tapered outlet 432, and a tapered outlet nozzle 434 (which can be formed as a cap covering and sealing the tapered outlet). The chamber C has an inner diameter DC. The outlet nozzle 434 is tapered from a larger inner diameter D1 at its proximal end to a smaller inner diameter D2 at its distal end. The outlet 432 connects the chamber C and the outlet nozzle 434 and is consequently tapered from a proximal inner diameter of diameter DC to a distal inner diameter of diameter D1.

[0063] As shown in FIG. 15B, the buoyant or hollow plug 440 has an upper portion 442 defined by a substantially uniform diameter Dj along its longitudinal dimension T, a substantially frustoconical intermediate portion 444 that is tapered from a proximal diameter of Dj to a distal diameter of Dk, and a substantially frustoconical bottom portion 446 that is tapered from a proximal diameter of Dk to a distal diameter of Dm. In some embodiments, the overall length L of the plug 440 is greater than or at least slightly greater than the chamber diameter DC such that the plug remains substantially upright within the chamber when floating. In some embodiments, the combination of the length L1 of the upper portion 442 and the length L2 of the intermediate portion 444 is less than or equal to the length L3 of the bottom portion 446, which helps to maintain the plug in a substantially upright position. In particular, the tapered intermediate portion 444 helps the plug 440 to self-align with the outlet nozzle 434, and the inclined inner sidewall 433 of the outlet 432 biases and guides the lower portion 446 of the plug into the outlet nozzle 434 as the chamber C depletes the fluid F and the plug 440 drops within the drip chamber 430.

[0064] The above dimensional relationships can be expressed as follows. DC < LT (Equation 2) L3 ≥ L1 + L2 (Equation 3) DC > Dj > Dk > Dm (Equation 4) Wherein, DC = inner diameter of the chamber C LT = overall length of the plug 430 L1 = length of the upper portion 442 L2 = length of the intermediate portion 444 L3 = length of the outlet nozzle 446 Dj = inner diameter of the upper portion 442 Dk = lower / distal inner diameter of the intermediate portion 444 Dm = lower / distal inner diameter of the lower portion 446

[0065] In particular, as shown in Figure 15C, the tapered portion of the middle section 444 of the plug 440 is larger / sharper than the tapered portion of the inner surface 433 of the outlet 432, so that when the plug 440 is seated on the outlet nozzle 446, the annular space gap G exits from between the middle section 444 and the inner surface 433. In this way, when the plug 440 is seated on the outlet nozzle 446 (shown by dashed lines in Figures 15A and 15C), the plug can have an upper section 442 and a middle section 444 surrounded by fluid, ensuring that the chamber C floats when replenished with fluid from a new IV bag that receives the bag spike of the dripping chamber 430.

[0066] The above description is provided in relation to preferred embodiments of the present invention as of now. Those skilled in the art will recognize that modifications and changes can be made to the described structures without departing in a substantial manner from the principles, spirit, and scope of the invention. Any feature or configuration disclosed in one embodiment can be incorporated, as needed or as appropriate, in place of or in addition to other features of any other embodiment. As those skilled in the art will understand, the drawings are not necessarily to scale. Therefore, the above description should not be read in relation only to the exact configurations described and illustrated in the accompanying drawings, but rather in accordance with and in support of the following claims, which are deemed to have the most complete and fair scope.

[0067] [Implementation Method] (1) an electrophysiological system, A guide sheath assembly, A long, slender shaft, A control handle located proximal to the shaft, comprising a shuttle having a longitudinal axis and a deflection control knob, configured to move in translational motion along the longitudinal axis in response to operation of the control knob, A puller wire extending along the shaft and responding to the translational motion of the shuttle in order to deflect the elongated shaft, the puller wire having a stopper at its proximal end, A guide sheath assembly including a deflection sensor configured to generate a signal in response to compression between the shuttle and the stopper when the elongated shaft is deflected, A control device that receives the signal and, To measure the voltage from the aforementioned signal, and, An electrophysiological system comprising: a control device having a processor configured to perform the operation of determining the occurrence of deflection based on the measured voltage. (2) The system according to Embodiment 1, wherein the processor is further configured to perform an operation to determine the degree of deflection based on the measured voltage. (3) The system according to Embodiment 2, wherein the console includes a memory configured to store an index that correlates a predetermined voltage with a predetermined degree of deflection, and the processor is further configured to access the index to determine the degree of deflection based on the measured voltage. (4) The system according to Embodiment 1, wherein the deflection sensor includes a piezoelectric pressure sensor. (5) The system according to Embodiment 1, further comprising an instruction mechanism configured to provide a user with a signal indicating the occurrence of the deflection in response to the control device and based on the measured voltage.

[0068] (6) The system according to embodiment 5, wherein the instruction mechanism is configured to provide a visual signal. (7) The system according to embodiment 5, wherein the instruction mechanism is configured to provide an audible signal. (8) an electrophysiological catheter, A long, slender shaft, A control handle located on the proximal side of the aforementioned shaft, having a longitudinal axis and a control knob, A rocker that responds to the control knob in order to deflect the elongated shaft, the rocker having a pulley member, A tension member having a distal portion extending through the shaft and a proximal portion extending around the pulley member, A connector extending between the distal portion and the proximal portion of the tension member, An electrophysiological catheter comprising a control handle, including a strain gauge fixed to the connector and configured to generate a signal in response to strain in the connector. (9) A dropper chamber, A hollow housing that defines a chamber communicating with the inlet and outlet, The bag spike at the aforementioned entrance, An outlet nozzle located distal to the aforementioned outlet, A dropping chamber comprising: a spherical plug configured to float when liquid is present in the chamber and to fall into the outlet nozzle under gravity when there is no liquid in the chamber, thereby providing a fluid-tight seal within the outlet nozzle.

Claims

1. It is an electrophysiological system, A guide sheath assembly, A long, slender shaft, A control handle located proximal to the shaft, comprising a shuttle having a longitudinal axis and a deflection control knob, configured to translate along the longitudinal axis in response to operation of the control knob, A puller wire extending along the shaft and responding to the translational motion of the shuttle in order to deflect the elongated shaft, the puller wire having a stopper at its proximal end, The system includes a deflection sensor configured to generate a signal in response to compression between the shuttle and the stopper when the elongated shaft is deflected, The deflection sensor is positioned on the stopper-side surface of the proximal end of the shuttle, in a guide sheath assembly, A control device that receives the signal and, To measure the voltage from the aforementioned signal, and, An electrophysiological system comprising: a control device having a processor configured to perform the operation of determining the occurrence of deflection based on the measured voltage.

2. The system according to claim 1, wherein the processor is further configured to perform an operation to determine the degree of deflection based on the measured voltage.

3. The system according to claim 2, wherein the console includes a memory configured to store an index that correlates a predetermined voltage with a predetermined degree of deflection, and the processor is further configured to access the index to determine the degree of deflection based on the measured voltage.

4. The system according to claim 1, wherein the deflection sensor includes a piezoelectric pressure sensor.

5. The system according to claim 1, further comprising an instruction mechanism configured to respond to the control device and to provide a user with a signal indicating the occurrence of the deflection based on the measured voltage.

6. The system according to claim 5, wherein the instruction mechanism is configured to provide a visual signal.

7. The system according to claim 5, wherein the instruction mechanism is configured to provide an audio signal.

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