Devices, systems, and methods for imaging and treating a selected tissue
11154186 · 2021-10-26
Assignee
Inventors
- Frank B. SACHSE (Salt Lake City, UT, US)
- Robert W. Hitchcock (Sandy, UT, US)
- Nassir F. Marrouche (Park City, UT, US)
- Nathan J. Knighton (Salt Lake City, UT, US)
- Chao Huang (Fruit Heights, UT, US)
Cpc classification
A61B1/07
HUMAN NECESSITIES
A61B5/287
HUMAN NECESSITIES
A61B18/1492
HUMAN NECESSITIES
A61B2018/0212
HUMAN NECESSITIES
A61B1/05
HUMAN NECESSITIES
A61B1/00167
HUMAN NECESSITIES
A61B1/042
HUMAN NECESSITIES
A61B2018/00982
HUMAN NECESSITIES
International classification
A61B1/07
HUMAN NECESSITIES
A61B1/00
HUMAN NECESSITIES
A61B1/012
HUMAN NECESSITIES
A61B1/04
HUMAN NECESSITIES
Abstract
A catheter for imaging and treating a selected tissue and method of use is provided. Imaging, and treatment assemblies may be co-located at a distal end of a single catheter. The imaging assembly may include at least a portion of a confocal microscope. The treatment assembly may include at least a portion of the imaging assembly. A method of treating a selected tissue is also provided. The method may be performed using a single catheter. The imaging and treatment steps of the method may be performed simultaneously.
Claims
1. A device for imaging and treating targeted cardiac tissue of a subject, the device comprising: an elongated sheath extending between a distal end and a proximal end, the elongated sheath having a lumen; a housing of fixed size disposed at the distal end of the elongated sheath and forming a distal tip of the device, the housing having a distally-facing aperture and comprising a conductive material; a fiber-optic bundle extending through the lumen of the sheath to the aperture and being in communication with the aperture, the fiber-optic bundle being disposed so as to transmit and receive light through the aperture; one or more energy application wires extending through the lumen of the sheath and conductively coupling with the housing to enable transfer of energy through the one or more energy application wires to the housing; and one or more mapping electrodes disposed as rings around the circumference of the sheath and/or housing, wherein the rings are spaced apart and disposed at different axial locations along a length of the sheath and/or housing.
2. The device of claim 1, wherein the energy application wires and the housing are configured to transfer one or more of radiofrequency electrical waves, microwaves, heat, and cold.
3. The device of claim 1, wherein the housing includes an inner section and an outer section, the inner section being formed of an insulating material and the outer section comprising the conductive.
4. The device of claim 3, wherein one or more lenses are housed within the inner section, the one or more lenses being in communication with the fiber-optic bundle.
5. The device of claim 3, wherein the outer section circumferentially surrounds the inner section, and the inner section defines the aperture.
6. The device of claim 1, wherein an exterior circumference of the housing is conductive.
7. The device of claim 1, wherein the elongated sheath is steerable.
8. The device of claim 1, wherein the fiber-optic bundle is configured to produce an image of tissue of the subject at a resolution of less than about 4 μm.
9. A device for imaging and treating targeted cardiac tissue of a subject, the device comprising: an elongated sheath extending between a distal end and a proximal end, the elongated sheath having a lumen; a housing of fixed size and shape disposed at the distal end of the elongated sheath and forming a distal tip of the device, the housing having a distally-facing aperture and being formed at least partially of a conductive material; a fiber-optic bundle extending through the lumen of the sheath to the housing and being in communication with one or more lenses disposed within the housing and with the aperture, the fiber-optic bundle being disposed so as to transmit and receive light through the aperture; one or more energy application wires extending through the lumen of the sheath and conductively coupling with the housing to enable transfer of energy through the one or more energy application wires to the housing; and one or more mapping electrodes disposed as rings around the circumference of the sheath and/or housing, wherein the rings are spaced apart and disposed at different axial locations along a length of the sheath and/or housing.
10. The device of claim 9, wherein the housing includes an inner section and an outer section, the inner section being formed of an insulating material and the outer section comprising the conductive material.
11. The device of claim 10, wherein the outer section circumferentially surrounds the inner section, and the inner section defines the aperture.
12. The device of claim 9, wherein the energy application wires and the housing are configured to transfer one or more of radiofrequency electrical waves, microwaves, heat, or cold.
13. The device of claim 9, wherein the elongated sheath is steerable.
14. A device for imaging and treating targeted cardiac tissue of a subject, the device comprising: an elongated sheath extending between a distal end and a proximal end, the elongated sheath having a lumen; a housing of fixed size disposed at the distal end of the elongated sheath and forming a distal tip of the device, the housing having a distally-facing aperture and comprising a conductive material; a confocal microscope assembly comprising a fiber-optic bundle extending through the lumen of the sheath to the aperture and being in communication with the aperture, the fiber-optic bundle being disposed so as to transmit and receive light through the aperture; one or more energy application wires extending through the lumen of the sheath and conductively coupling with the housing to enable transfer of energy through the one or more energy application wires to the housing; and one or more mapping electrodes disposed as rings around the circumference of the sheath and/or housing, wherein the rings are spaced apart and disposed at different axial locations along a length of the sheath and/or housing.
15. The device of claim 14, wherein the elongated sheath is steerable.
16. The device of claim 14, wherein the fiber-optic bundle is configured to produce an image of tissue of the subject at a resolution of less than about 4 μm.
17. The device of claim 14, wherein the housing includes an inner section formed from an insulating material and an outer section formed from the conductive material, the outer section circumferentially surrounding the inner section.
18. The device of claim 17, wherein the outer section circumferentially surrounds the inner section, and the inner section defines the aperture.
19. The device of claim 17, wherein one or more lenses are housed within the inner section, the one or more lenses being in communication with the fiber-optic bundle.
20. The device of claim 14, wherein the energy application wires and the housing are configured to transfer one or more of radiofrequency electrical waves, microwaves, heat, or cold.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) In order to describe the manner in which the above-recited and other features of the disclosure can be obtained, a more particular description will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. For better understanding, the like elements have been designated by like reference numbers throughout the various accompanying figures. While some of the drawings may be schematic or exaggerated representations of concepts, at least some of the drawings may be drawn to scale. Understanding that the drawings depict some example embodiments, the embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
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DETAILED DESCRIPTION
(30) The present disclosure includes devices, systems, and methods for imaging, treating, and/or mapping a selected tissue of a subject. The device, which is often referred to in a non-limiting fashion as a catheter, includes an imaging assembly, a treatment assembly, and a mapping assembly. A treatment assembly may include an energy application assembly and/or a drug delivery assembly. At least a portion of each of these assemblies may be co-located at the distal end or tip of the catheter so that only one catheter is needed to perform the imaging, mapping, and treating of a selected tissue of a subject, such as, for example, the interior tissue of a heart. At least one embodiment described herein enables the imaging, mapping, and treatment (e.g., ablation and/or drug delivery) of a selected tissue to be performed with a single instrument without the need to insert multiple instruments into a subject. In other words, the imaging, mapping, and treatment (e.g., ablation and/or drug delivery) may be performed without inserting an additional imaging, mapping, or treatment (e.g., ablation and/or drug delivery) device.
(31) At least one or more embodiments disclosed herein may provide the following advantages: The integration of steering, imaging, mapping and treatment (e.g., ablation and/or drug delivery) in a single device will allow an operator, such as a doctor, to develop and evaluate new diagnostic and therapeutic approaches. One example application is cardiac ablation using the energy application assembly guided by images of tissue microstructure from the imaging assembly. Another example application is diagnosis of diseases based on integrated imaging of tissue microstructure and electrical mapping.
(32) At least one embodiment described herein is capable of treating (e.g., ablation and/or drug delivery) internal heart tissue while the heart is blood filled and beating. For example, at least one embodiment described herein may image, map, and treat (e.g., ablate and or deliver drug) a portion of an interior surface of the heart tissue with a single device while the heart is filled with blood and/or beating.
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(34) Examples of thermoset materials may be used include but are not limited to: polyimide, epoxy, silicone and copolymers of these types of materials. Other materials such as metals and polymer filaments may be used in the construction of these catheters to impart specific physical, electrical, optical and mechanical properties.
(35) An imaging assembly 106 and an energy application assembly 108, as well as an optional mapping assembly 110 (shown in phantom), are each shown at least partially disposed within the bore 105 at the distal tip 109 of the catheter 100. At least part of the imaging assembly 106, the energy application assembly 108, and the mapping assembly 110 may be co-located at the distal tip 109 of the catheter 100. For example, a distal end of the imaging assembly 106, a distal end of the energy application assembly 108, and a distal end of the mapping assembly 110 may be located at the distal tip 109.
(36) Although the various embodiments disclosed herein are generally directed to energy application assemblies, in some embodiments in addition to or instead of the energy application assembly a drug delivery assembly may be used. The drug delivery assembly may include a lumen through which various agents may be delivered. The agents that may be delivered may include, but are not limited to, beneficial agents such as cytotoxins, antifibrotic drugs, anti-inflammatory drugs, ion channels blockers and activators, cytokines, other drugs, or combinations thereof and/or tissue ablating agents, such as alcohol.
(37) The integration of the imaging assembly 106, the energy application assembly 108, and the mapping assembly 110 facilitates, in at least one embodiment, the imaging, treatment (e.g., ablation and/or drug delivery), and/or mapping of a selected tissue to be performed with a single instrument, such as the catheter 100 illustrated in
(38) At least one embodiment of a device (e.g., catheter 100) may facilitate the imaging, treating (e.g., ablating and/or delivering drug), and/or mapping of a selected tissue to be performed from the inside of the subject, without the need for additional imaging or mapping instruments. For example, in at least one embodiment, it is not necessary to use a computer tomographic system, magnetic resonance imaging system, or fluoroscope exterior to the subject in order to image the selected tissue during a treatment (e.g., ablation and/or delivering drug) and mapping of the selected tissue. In at least one embodiment with a mapping assembly (e.g., mapping assembly 110), it may not be necessary to use additional mapping instruments to map the electrical activity of the selected tissue while a separate instrument (e.g., catheter 100) images and/or treats (e.g., ablates and/or delivering drug) the selected tissue from inside the subject. Components of the other devices (e.g., catheters) described herein may be incorporated into, and vice versa, the catheter 100 of
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(40) A conduit 214 may be in communication with the port 212 and extend into the catheter 200. As illustrated in
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(42) Each branch conduit 316, 318 may be in communication with the base conduit 314. One or more assemblies (e.g., imaging assembly 106, an energy application assembly 108, a mapping assembly 110, imaging assembly 206, assembly 306, assembly 308, other assemblies, or combinations thereof) residing in two or more branch conduits (e.g., one or more branch conduits 316, 318) may be selectively advanced into the branch conduits. For example, a first assembly (e.g., one of the assemblies described herein) may be advanced and/or retracted into, through, out of the base conduit 314, or combinations thereof and a second assembly may be advanced and/or retracted into, through, out of the base conduit 314 or combinations thereof.
(43) In some embodiments, each assembly may selectively extend beyond the distal tip 309 of the catheter 300 as illustrated in
(44) Components of the other devices (e.g., catheters) described herein may be incorporated into, and vice versa, the catheter 300 of
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(46) Components of the other devices (e.g., catheters) described herein may be incorporated into, and vice versa, the catheter 400 of
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(50) Furthermore, multiple attachment collars 522 may be attached to the catheter 500 along its length. Multiple attachment collars 522 may enable multiple sections of the catheter 500 to be bent and/or steered. For example, the attachment collar 522 shown in
(51) The energy application assembly 508 may be connected to an energy application wire 534 as shown. The energy application assembly 508 will be described further detail below. The imaging assembly 506 may be positioned within an imaging housing 528. The imaging housing 528 will be described in further detail below. The imaging housing 528 may include a fiber-optic bundle 526. The fiber-optic bundle 526 may be used to facilitate imaging of the selected tissue, as further described below.
(52) Components of other devices (e.g., for imaging, treating (e.g., ablating and/or delivering drug), and/or mapping) may be incorporated into, and vice versa, the catheter 500 of
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(55) Components of the other devices (e.g., for imaging and treating (e.g., ablating and/or delivering drug)) described herein may be incorporated into, and vice versa, the catheter 600 of
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(57) Components of the other devices (e.g., for imaging and treating (e.g., ablating and/or delivering drug)) described herein may be incorporated into, and vice versa, the catheter 700 of
(58) The imaging assembly illustrated in
(59) In some embodiments of an imaging assembly 606, the fiber-optic bundle 626, as well as the imaging housing 628, may have a diameter of between about 0.2 mm and about 5 mm. The fiber-optic bundle 626 may also have a length of between about 10 cm and about 10 m. In some embodiments, the imaging assembly 606 may be configured to produce and imaged of a selected tissue with a spatial resolution ranging from 1 μm to 100 μm. In other embodiments, the imaging assembly 606 may be configured to produce an image, image sequence or image stack of a selected tissue at a spatial resolution of less than about 4 μm. For example, the imaging assembly 606 may be configured to produce an image at a spatial resolution between 1.8 μm and 3.9 μm transverse to the direction of optical axis of the at least one lens 732.
(60) Although described herein as comprising a fiber-optic bundle 626, the imaging assembly 606 may comprise any mechanism for transmitting an image from an objective lens 732 to an image processing system, including any known image-transmitting media. For example, the imaging assembly 606 may comprise at least one of a clear rod, a single wire, a plurality of wires, a microscopic camera, and the like, to effect transmission of an image as disclosed herein.
(61) The imaging assembly 606 may be positioned in communication with a light source (not shown in
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(63) Energy application wires 834, which may be in communication with the dual-purpose housing, may carry energy, such as electricity or heat, from a source (not shown) to the dual-purpose housing.
(64) The energy application housing 836 and wires 834 are configured to apply energy to a selected tissue. This energy may be in the form of radiofrequency electrical waves, microwaves as well as heat and cold.
(65) Components of other devices (e.g., for electrical mapping) may be incorporated into, and vice versa, the catheter 800 of
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(67) Components of other devices (e.g., for mapping) may be incorporated into, and vice versa, the catheter 900 of
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(69) Components of the other devices (e.g., catheters) described herein may be incorporated into, and vice versa, the catheter 1000 of
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(71) The energy application housings 836, 936, 1236, 1336, 1436, 1836, described herein, which may or may not be the same component as the imaging housings 528, 628, 728, 828, 928, 1028, 1228, 1328, 1428, described herein, and energy application zones 1038, 1138 described herein, are configured to supply energy to a selected tissue. The energy applied may ablate the selected tissue. The energy application housings and energy application zones may comprise platinum-iridium tip electrodes or gold-tip electrodes. However, any energy application electrodes, including conventional ablation electrodes, may be used.
(72) Components of other devices (e.g., for mapping) may be incorporated into, and vice versa, the catheter 1100 of
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(74) As shown in
(75) It is contemplated that each mapping electrode 1210 of the plurality of mapping electrodes 1210 of the mapping assembly (not shown) may be configured to record electrical activity within a selected tissue. In some embodiments, each respective mapping electrode of the plurality of mapping electrodes 1210 may include a steel electrode, a stainless steel electrode, a silver-silver-chloride electrode, other electrodes, or combinations thereof.
(76) The mapping electrodes 1210 are configured to record electrical signals from a selected tissue. Such electrical signals reflect conduction pathways and disturbances including arrhythmia as well as cellular activity and dysfunction. Measurements of the mapping electrodes include electric potentials, impedance, and/or resistance of a selected tissue.
(77) Components of other devices (e.g., for imaging, treating (e.g., ablating and/or delivering drug), and/or mapping) may be incorporated into, and vice versa, the catheter 1200 of
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(79) The mapping electrodes 1310 may be disposed on the outer circumference of the catheter 1300 and extend to a distal tip 1309 of the catheter 1300.
(80) Mapping electrodes 1310 may be selectively advanced through ports (e.g., port 212, 312, 412, 1112) and may be independently steerable. Other embodiments may include other configurations of mapping electrodes 1310 and/or modes of operability. Other configurations of mapping electrodes 1310 and/or deployment modalities may also be used in the embodiments herein described and/or other embodiments.
(81) Components of other devices (e.g., for imaging, treating (e.g., ablating and/or delivering drug), and/or mapping) may be incorporated into, and vice versa, the catheter 1300 of
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(84) The embodiment illustrated in
(85) Components of other devices (e.g., for imaging, treating (e.g., ablating and/or delivering drug), and/or mapping) may be incorporated into, and vice versa, the catheter 1400 of
(86) A method for treating a selected tissue of a subject, such as a portion of an interior surface of the interior tissue of a heart, may include imaging, mapping, and treating the selected tissue. In one or more embodiments, the imaging, mapping, and treating may be done simultaneously. In at least one embodiment, the imaging, mapping, and treating steps performed on the selected tissue may be done using a single instrument, such as one or more of the catheters herein described. In at least one embodiment, it may not be necessary to withdraw and insert multiple instruments and/or catheters in order to perform these different steps. The imaging, mapping, and treating (e.g., ablating and/or delivering drug) of selected tissue may be performed from the interior of a subject, such as the interior of a heart or other organ, in order to effectively treat (e.g., ablate and/or deliver drug) a selected tissue, such as the interior wall of a heart or other organ tissue.
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(88) The insertion of a catheter and the locating 1502 of a selected tissue is described in more detail below in reference to
(89) An energy application assembly of a catheter as described herein may apply radiofrequency energy to the selected tissue in order to ablate the tissue. Radiofrequency energy is one example of energy that may be applied to the selected tissue. Other examples of applied energy may include microwaves as well as heat and cold The energy applied to the selected tissue may increase or decrease the temperature of the tissue to a point where the cells within the tissue die, thus ablating the tissue.
(90) A drug delivery assembly of a catheter as described herein may deliver a drug to treat a selected tissue. Treating a selected tissue may include providing a beneficial or deleterious agent to the selected tissue. For example, the one or more agents may be delivered may include, but are not limited to, beneficial agents such as cytotoxins, antifibrotic drugs, anti-inflammatory drugs, ion channels blockers and activators, cytokines, other drugs, or combinations thereof and/or deleterious agents, such as, tissue ablating agents, including, but not limited to, alcohol.
(91) Components of the other methods described herein may be incorporated into, and vice versa, the method 1500 of
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(93) Imaging and/or mapping of the selected tissue while treatment is occurring 1512 may provide a second set of outputs to the processor and/or operator of the catheter. These second set of outputs may be used to determine whether sufficient treatment (e.g., sufficient ablation and/or sufficient drug delivery) has occurred and when to stop treatment. Once treatment has been performed, the tissue may then be imaged and/or mapped again 1508, as shown in
(94) Components of the other methods described herein may be incorporated into, and vice versa, the method 1501 of
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(96) A fiber-optic confocal microscope (FCM) system 1640 may be included as an imaging assembly. The FCM may include an FCM probe fiber 1642. The FCM system 1640 may be in communication with a control wand 1644 of the catheter 1600 via the FCM probe fiber 1642. The FCM system 1640 may be configured to provide a light source and light detector components (not shown) that may be in communication with a fiber-optic bundle (not shown) of the catheter system 1600. Other imaging systems may also be provided. For example, the imaging system may be a fluorescent microscope system. Other systems may include, but are not limited to, fluorescence microscope, multiphoton imaging system, optical coherence tomography system, and super-resolution optical imaging systems.
(97) A radiofrequency (RF) ablation system 1646 may be provided as an energy ablation assembly. The RF ablation system 1646 may include an RF connector cable 1648. The RF ablation system 1646 may be in communication with the catheter system 1600 via the RF connector cable 1648. The RF connector cable 1648 may be attached to the control wand 1644 via a RF multi-pin connector 1650. The RF ablation system 1646 may supply radiofrequency energy to an energy application assembly (not shown) of the catheter system 1600. An actuator 1652 (e.g., a foot control) may be provided and configured to selectively activate the RF ablation system 1646 when ablation of a selected tissue is desired.
(98) In some embodiments in addition to or instead of the energy application assembly a drug delivery assembly may be used. The drug delivery assembly may include a lumen through which various agents may be delivered. The agents that may be delivered may include, but are not limited to, beneficial agents such as cytotoxins, antifibrotic drugs, anti-inflammatory drugs, ion channels blockers and activators, cytokines, other drugs, or combinations thereof and/or tissue ablating agents, such as alcohol.
(99) Components of other devices (e.g., for imaging, treating (e.g., ablating and/or delivering drug), and/or mapping) may be incorporated into, and vice versa, the catheter system 1600 of
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(101) The catheter 1700 may be advanced through blood vessels and a right atrium 1756, across an atrial septum 1758 and into a left atrium 1760. A selected tissue 10 to treat (e.g., ablate and/or deliver drug) may be on an interior portion of the left atrium 1760. The selected tissue 10 may be the interior cardiac tissue of a blood-filled, beating heart 1762. Cardiac tissue is one example of tissue that may be selected for treatment (e.g., ablation and/or drug delivery). Other examples of selected tissues may include, but are not limited to, pulmonary, gastrointestinal, urogynecologic, endocrine, neural and vascular tissues.
(102) As the catheter 1700 is inserted into a subject, the imaging assembly may be producing images and/or image sequences of the interior of the subject. These images and/or image sequences may assist an operator, such as a doctor, in viewing and locating a selected tissue as the catheter is being inserted. The catheter 1700 may map the tissue inside of the subject as it is being inserted, further characterizing the tissue and assisting in locating the tissue and positioning the mapping and treatment (e.g., ablation and/or drug delivery) devices.
(103) The catheter 1700 may be steered and/or bent using actuation wires, as described herein, in order to navigate within a subject to reach the selected tissue 10. In other embodiments, the catheter 1700 may be inserted into a left atrium 1756 of a heart 1762 so that a distal end of the catheter 1700 is in close proximity to a portion of selected tissue without steering or using the actuation wires. For example, a steerable guide catheter may be used. Once the distal tip of the catheter 1700 is in close proximity to the selected tissue 10, the actuation wires may be used to bend the catheter 1700 so that the distal end of the catheter 1700 comes in contact with the selected tissue 10.
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(105) The catheter 1800 may include a mapping assembly 1810, an energy application housing 1836, and a confocal microscope imaging assembly 1806. The light path 1866 is emitted from the confocal microscope imaging assembly 1806 may be such that a focal point 1864 may be located within a depth of the selected tissue 10. The confocal microscope imaging assembly 1806 may provide a depth of focus of 25 to 100 μm beneath the tissue 10 surface.
(106) The imaging assembly 1806 and mapping assembly 1810 of the catheter 1800 may be in direct contact with the selected tissue 10. In some embodiment the imaging assembly 1806 may not be advanced beyond the distal tip 1809 of the catheter 1800, but may still provide an image of the tissue 10 as it resides within the catheter 1800.
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(115) Performing certain steps of the method of treating (e.g., ablating and/or delivering drug) a selected tissue at a repeatable trace point in time may ensure more accurate and repeatable results. As illustrated in
(116) Performing steps of the method of treating (e.g., ablating and/or delivering drug) a selected tissue at a repeatable trace point ensures that treating, mapping, and imaging steps of the method are done while the catheter 2700 is in the same position relative to the selected tissue contact point 2780. This may ensure more repeatable and reliable treatment results.
(117) The present disclosure may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. All references (e.g., journal articles, published patent applications, patents, websites, and the like) that are recited herein are incorporated herein by specific reference in their entirety.
(118) The articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements in the preceding descriptions. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. For example, any element described in relation to an embodiment herein may be combinable with any element of any other embodiment described herein. Numbers, percentages, ratios, or other values stated herein are intended to include that value, and also other values that are “about” or “approximately” the stated value, as would be appreciated by one of ordinary skill in the art encompassed by embodiments of the present disclosure. A stated value should therefore be interpreted broadly enough to encompass values that are at least close enough to the stated value to perform a desired function or achieve a desired result. The stated values include at least the variation to be expected in a suitable manufacturing or production process, and may include values that are within 5%, within 1%, within 0.1%, or within 0.01% of a stated value. For example, the use of the term “parallel” may include deviations from parallel of within 5%, within 1%, within 0.1%, or within 0.01% of a stated value.
(119) A person having ordinary skill in the art should realize in view of the present disclosure that equivalent constructions do not depart from the spirit and scope of the present disclosure, and that various changes, substitutions, and alterations may be made to embodiments disclosed herein without departing from the spirit and scope of the present disclosure. Equivalent constructions, including functional “means-plus-function” clauses are intended to cover the structures described herein as performing the recited function, including both structural equivalents that operate in the same manner, and equivalent structures that provide the same function. It is the express intention of the applicant not to invoke means-plus-function or other functional claiming for any claim except for those in which the words ‘means for’ appear together with an associated function. Each addition, deletion, and modification to the embodiments that falls within the meaning and scope of the claims is to be embraced by the claims. It should be understood that any directions or reference frames in the preceding description are merely relative directions or movements. For example, any references to “front” and “back” or “top” and “bottom” or “left” and “right” are merely descriptive of the relative position or movement of the related elements.