Optically Guided Ablation System for Use With a Pulsed Field Energy Source - Patent application

Abstract

Described herein is a system including a catheter, an optical circuit, a pulsed field ablation energy source, and a processing device. The catheter includes a proximal section, a distal section, and a shaft coupled between the proximal and distal sections. The optical circuit is configured to transport light at least partially from the proximal section to the distal section and vice versa. The pulsed field ablation energy source is coupled to the catheter and configured to transmit pulsed electrical signals to a tissue sample. The processing device is configured to analyze one or more optical signals received from the optical circuit and determine changes in polarization or phase delay of light reflected or scattered by the tissue sample, and to determine changes in birefringence of the tissue sample based on the changes in polarization or phase delay.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to EP Application No. 20382014.7, filed January 13, 2020, and EP Application No. 20382774.6, filed August 31, 2020, the disclosures of which are incorporated herein by reference in their entireties.

[0002] SUMMARY OF THE DISCLOSURE Embodiments of the present application relate to catheters, systems, and methods that utilize optical photonic techniques to determine or predict structural changes in tissue associated with ablation-based lesions. [Background technology]

[0003] Several medical conditions are treated by ablating healthy tissue to create lesions to affect local tissue or end-organ function. Primary examples of such treatments include myocardial ablation for patients with cardiac rhythm abnormalities, renal nerve ablation (e.g., renal denervation) for patients with hypertension, and nerve ablation for the treatment of patients with epilepsy. In such procedures, catheters are used to locally deliver the energy required to ablate tissue via intravascular access or small incisions. Energy used to create lesions can include conventional radio frequency (RF)-based heat, cryogenic cooling, and pulsed field ablation.

[0004] Atrial fibrillation (AF) is a common type of cardiac arrhythmia that affects an estimated 33.5 million people worldwide in 2010. AF increases the risk of stroke by 5-fold and is a major medical problem in developed countries. Available drug therapies that are commonly used to control the heart rhythm of AF patients can have significant drawbacks in terms of efficacy and can cause serious side effects, resulting in a reduced quality of life for patients. Cardiac catheter ablation therapy can be a minimally invasive procedure that employs a thin, steerable therapeutic catheter that uses energy to create lesions in cardiac tissue to treat cardiac rhythm abnormalities. The success of the therapy depends on the clinician's ability to completely ablate tissue through the cardiac wall without missing any gaps between ablation points that could cause AF recurrence. Currently, clinicians cannot determine in real time the quality of catheter contact, contractile stability, energy delivered, or the quality of the ablation performed. Conventional RF cardiac ablation can also result in significant complications associated with puncture or unintended thermal damage to adjacent structures. This is because such ablation uses thermal means to create lesions. In that regard, Pulsed Field Ablation (PFA) uses electromagnetic pulses to generate non-thermal lesions during the ablation process. PFA uses electrodes to cause irreversible electroporation of cells therein, ultimately resulting in cell death. This technique reduces complications associated with thermal damage, but there may be limited or minimal necrosis in the tissue at the surface of the electrode due to thermal damage. Current technology is limited in indicating to the clinician whether the lesions created by PFA energy at selected parameters will result in irreversible electroporation and subsequent permanent lesions. The lack of such information may lead to significant levels of fibrillation recurrence.Having the ability to directly assess lesion creation through the use of photonics will enable clinicians to create safer, more durable and sequential lesions to treat AF and prevent its recurrence.

[0005] Epilepsy is the fourth most common neurological disorder, affecting people of all ages. Treatment options to date include medication, neurostimulation, surgery, and ablation. Laser ablation using a catheter is one of the more recently used procedures because it is less invasive than surgery and can eliminate the seizure focus by ablating the area that causes the seizures. Efficacy and safety limitations of this procedure are associated with the inability to precisely measure the amount of energy (e.g., heat) delivered into the tissue, because too much energy can damage surrounding neurons and too little energy would require re-ablation. Thus, a catheter that can determine the amount of energy or the local temperature at the tissue site would alleviate some of the shortcomings of the current technology.

[0006] Several clinical studies have shown that ablation of renal nerves can reduce blood pressure in hypertensive patients. This procedure and other ablation procedures may be limited by the correct delivery of energy to generate the desired lesion geometry. Too little energy can result in a lesion that may not penetrate sufficiently into the tissue, leaving a transmission gap and the need for subsequent reintervention, while too much energy can result in complications such as renal artery stenosis or dissection. Renal denervation would therefore benefit from the use of photonic-based catheters that can predict lesion geometry based on measurements of real-time tissue temperature at the ablated site.

[0007] Low Coherence Interferometry (LCI) is often used in medical imaging to provide depth-resolved information of both internal and external tissues. Exemplary LCI techniques include Optical Coherence Reflectrometry (OCR) and Optical Coherence Tomography (OCT), which can provide depth-resolved information with high axial resolution from a broadband light source and an interferometric detection system, respectively. LCI techniques can be used to determine the structural properties of tissues and their changes as ablation lesions occur. Some of the optical variables that can be used to determine changes in tissue properties are frequency, time of flight, polarization, and intensity.

[0008] Spectroscopic techniques based on elastic optical scattering, fluorescence, and Raman scattering can perform disease diagnosis by characterizing the cellular / subcellular structures, cellular metabolic state, and molecular signatures of normal and diseased tissues, respectively. Optical spectroscopy techniques have been used to determine the geometry of different anatomical structures within tissues, and spectroscopy techniques have the benefit of increased penetration depth compared to some LCI techniques.

[0009] As discussed above, cardiac ablation, renal denervation, and nerve ablation catheter-based interventions suffer from significant limitations associated with the lack of real-time information during the clinical procedure to assess lesion progression after energy (e.g., RF, cryogenics, and / or pulsed fields) has been delivered to the selected site. Summary of the Invention

[0010] Thus, there may be a need to provide new catheters, systems, and methods that use optical techniques, such as LCI and spectroscopy, during and after energy delivery to assess lesion geometry to reduce the need for reintervention, improve safety, and ensure ablation accuracy.

[0011] Thus, described herein are embodiments of an optically guided ablation system including a catheter, an optical source, an optical circuit, an ablation energy source, and an ablation energy circuit. In various embodiments, the ablation system can be used with pulsed field ablation energy or RF ablation energy to treat cardiac fibrillation, epilepsy, or perform renal denervation. Changes in the polarization and phase delay of light used by the optically based catheter system described herein can be used to predict thermal lesion geometry during RF ablation, or tissue and cell structural changes associated with cell death in pulsed field ablation procedures.

[0012] In some embodiments, the ablation system includes a catheter with an optical waveguide or fiber, a data processing device, an optical source, an optical circuit, and an ablation energy source. The catheter includes a proximal section, a distal section, and a shaft connecting the proximal section to the distal section. In some embodiments, the proximal section includes a handle as an interface with a clinical user. In some embodiments, the optical fiber and / or waveguide, and the electrical wires and / or cables travel at least partially through the shaft of the catheter to transport the optical signal and the ablation energy to / from the patient's body. In some embodiments, the optical fiber and / or waveguide are part of an optical circuit that allows for the transmission and control of the optical signal emitted by the optical source. In some embodiments, the optical circuit includes an optical splitter and / or switch to split the optical signal from the optical source into different paths of the optical circuit to send the optical signal to different locations in or on the patient's body.

[0013] In some embodiments, electrical wires are used to transmit ablation energy from an ablation energy source to an ablation site inside or on the surface of the patient's body. In some embodiments, the ablation energy source is a pulsed field ablation (PFA) generator. In some embodiments, the PFA generator delivers a pulsed electrical signal (monophasic or biphasic) that generates a pulsed RF field to generate a localized lesion in the tissue at the ablation site. The electrical signal of the ablation energy source can travel through a wire or cable to an electrode positioned on the surface of the catheter shaft 202. The lesion can be generated by an electric field pulse from an electrode that is in contact with or penetrates into the tissue at the ablation site. The lesion can be thermal or non-thermal depending on the amount of energy transmitted into the tissue. In some embodiments, the energy source can be modulated to generate a lesion mostly associated with non-thermal damage of tissue structures. Non-thermal damage occurs when the ablation energy entering the tissue causes or increases the size of pores in the membranes of the cells of the tissue to open or increase in size to such an extent that cell edema is caused. Such cell edema can alter cellular functions to which the cells may respond by initiating apoptosis or other delayed cell death processes leading to cell death. Alterations in cell wall structures and subsequent cell death through apoptosis, pyroptosis, necroptosis, and / or necrotic processes can alter the birefringence properties of the ablated tissue. This is because denaturation and / or fragmentation of cell membrane proteins, cellular cytoskeleton proteins, or proteins in the extracellular matrix alter how light interacts with such proteins. Thus, the optical properties (e.g., polarization and phase retardation, etc.) of light reflecting or refracting from such denatured or fragmented structures lead to changes in tissue birefringence.

[0014] In some embodiments, an optical signal from the optical source travels through the optical circuit to an ablation site in or on the surface of the patient's body, either simultaneously or after ablation energy is transmitted into the tissue. In some embodiments, the light from the optical circuit penetrates the tissue and may be reflected, refracted, or backscattered into the optical circuit. The reflected, refracted, or scattered light travels at least partially back through the optical circuit to an optical detector. The optical detector is used to collect optical data about the characteristics of the returning light (e.g., intensity, frequency, polarization state, time of flight, and phase delay, etc.). In some embodiments, the optical data and characteristics are analyzed to determine changes in the birefringence of the treated tissue associated with the use of pulsed field energy for ablation. In some embodiments, data from the returning optical signal (including changes in the birefringence of the tissue) may then be sent to a computer or processor unit coupled to the optical detector. The computer or processor unit can apply interpolation, extrapolation, artificial intelligence (e.g., machine learning), and / or other statistical algorithms to the data from the returning optical signals so as to correlate changes in the received signal to the durability and / or geometry of the ablated lesion, as well as to the possible reoccurrence of cardiac fibrillation or other types of cardiac pacing abnormalities.

[0015] In an embodiment, an exemplary system is described. The system includes a catheter, an optical circuit, a pulsed field ablation energy source, and a processing device. The catheter includes a proximal section, a distal section, and a shaft coupled between the proximal section and the distal section. The optical circuit is configured to transport light at least partially from the proximal section to the distal section and vice versa. The pulsed field ablation energy source is coupled to the catheter and configured to transmit a pulsed electrical signal to the tissue sample. The processing device is configured to analyze one or more optical signals received from the optical circuit and determine a change in polarization or phase delay of light reflected or scattered by the tissue sample, and is configured to determine a change in birefringence of the tissue sample based on the change in polarization and phase delay.

[0016] In another embodiment, an exemplary method for performing ablation in a patient is described, the method including the steps of inserting a catheter into the patient's vasculature, moving a distal end of the catheter to an ablation site in the patient's vasculature, establishing tissue contact at the distal end of the catheter through optical means using light delivered through the distal end of the catheter to the ablation site, delivering energy from an energy source coupled to the catheter into the tissue from the distal end of the catheter, optically interrogating the ablated tissue site to determine a change in polarization or phase delay of the light delivered through the catheter to the ablated tissue site, and removing the catheter from the vasculature.

[0017] In another embodiment, a catheter for ablating tissue of a heart wall is described. The catheter includes a proximal end, a distal end, a plurality of electrodes disposed on the distal end at a predetermined distance from each other, and at least one optical port positioned on the distal end at a predetermined location relative to the plurality of electrodes. The catheter is configured to be placed within an outer sheath, such that the distal end assumes a straight configuration compatible with vascular delivery, and the distal end assumes a circular shape when pushed through the sheath. The plurality of electrodes are connected by wires to an external electrical energy generating device via an electrical connector on the proximal end of the catheter. The plurality of electrodes are configured to deliver electrical energy to the heart wall when excited by the external electrical energy generating device.

[0018] Further features and advantages, as well as the structure and operation of various embodiments, are described in detail below with reference to the accompanying drawings. It is noted that the specific embodiments described herein are not intended to be limiting. Such embodiments are presented herein for illustrative purposes only. Additional embodiments will be apparent to those skilled in the art based on the teachings contained herein. [Brief description of the drawings]

[0019] [Figure 1] 1 is a diagram of an exemplary ablation system comprising optical techniques for controlled tissue ablation, according to an embodiment of the present disclosure. [Diagram 2] 1 is a diagram of exemplary components of a catheter that may be used for controlled ablation, according to an embodiment of the present disclosure. [Figure 3A] 1 is a diagram illustrating an exemplary axial cross-sectional view of a distal segment of a catheter, according to an embodiment of the present disclosure. [Figure 3B] 1 is a diagram illustrating an exemplary radial cross-section of a distal segment of a catheter, according to an embodiment of the present disclosure. [Figure 4A] 1A-1D are diagrams of exemplary 2D and 3D configurations of a distal segment of a catheter used to accommodate ablation site geometries, according to embodiments of the present disclosure. [Figure 4B] 1A-1D are diagrams of exemplary 2D and 3D configurations of a distal segment of a catheter used to accommodate ablation site geometries, according to embodiments of the present disclosure. [Figure 4C] 1A-1D are diagrams of exemplary 2D and 3D configurations of a distal segment of a catheter used to accommodate ablation site geometries, according to embodiments of the present disclosure. [Figure 4D] 1A-1D are diagrams of exemplary 2D and 3D configurations of a distal segment of a catheter used to accommodate ablation site geometries, according to embodiments of the present disclosure. [Diagram 5] 1 is a diagram of an exemplary optical circuit according to an embodiment of the present disclosure. [Figure 6] 1 is a diagram of exemplary experimental histological images of myocardial tissue for an unablative sample and a sample after PFA ablation, according to an embodiment of the present disclosure. [Figure 7] 1 illustrates an exemplary method for clinical use of an optically guided pulsed field ablation system, according to an embodiment of the present disclosure. [Figure 8] 1 is a diagram of an exemplary distal end of a PFA-OCR catheter having a circular shape, according to an embodiment of the present disclosure. [Figure 9] 1 is an exemplary cross-sectional diagram of a side view of a distal tip portion of a distal section of a PFA catheter with OCR diagnostic functionality, according to an embodiment of the present disclosure. [Figure 10] 1 is an exemplary cross-sectional diagram of a side view of a distal section of a PFA catheter with OCR diagnostic functionality with a separately movable optical catheter inserted into its optical lumen, according to an embodiment of the present disclosure. [Figure 11]1 is an exemplary cross-sectional diagram of a distal section of a PFA-OCR catheter, according to an embodiment of the present disclosure. [Figure 12] 1 is an exemplary cross-sectional diagram of a side view of a distal section of a PFA catheter showing internal components, according to an embodiment of the present disclosure. [Figure 13] 1 is another exemplary cross-sectional diagram of a side view of a distal section of a PFA catheter, according to an embodiment of the present disclosure. [Figure 14] 1 is a diagram of an exemplary distal end of a PFA-OCR catheter system with two concentric catheters, according to an embodiment of the present disclosure. [Figure 15] 1 is a diagram of an exemplary section of a distal end of a PFA-OCR outer catheter, according to an embodiment of the present disclosure. [Figure 16] 1 is a diagram of an exemplary distal end of an inner catheter for translation within an outer catheter of a PFA-OCR catheter system, according to an embodiment of the present disclosure. [Figure 17] 1 is an exemplary cross-sectional diagram of a distal end of an inner catheter for translation within an outer catheter of a PFA-OCR catheter system, according to an embodiment of the present disclosure. [Figure 18] 18A and 18B are diagrams of an exemplary distal section of a PFA-OCR catheter system in which an inner catheter is inserted into an outer catheter, illustrating misalignment and alignment, respectively, of electrodes and openings in the catheter, according to an embodiment of the present disclosure. [Figure 19] 1 is a diagram of an exemplary cross section of an inner catheter and an outer catheter in a two-catheter system for PFA-OCR, according to an embodiment of the present disclosure. [Figure 20] 1 is a diagram of an exemplary cross section of an inner catheter and an outer catheter in a two-catheter system for PFA-OCR, according to an embodiment of the present disclosure. [Figure 21]1 is an exemplary cross-sectional diagram of a side view of a distal section of a PFA-OCR catheter system in which a movable optical catheter is configured to rotate within a stationary outer catheter, according to an embodiment of the present disclosure. [Figure 22] FIG. 1 is a diagram of an exemplary cross-sectional view of a two-catheter PFA-OCR system that allows selection of active measurement locations by rotation of one catheter relative to the other catheter, in accordance with an embodiment of the present disclosure. [Figure 23] FIG. 2 is a block diagram of exemplary components of a computer system according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0021] While specific configurations and arrangements are discussed, it should be understood that this is done for illustrative purposes only. Those skilled in the art will recognize that other configurations and arrangements can be used without departing from the spirit and scope of the present disclosure. It will become apparent to those skilled in the art that the present disclosure can also be used in a variety of other applications.

[0022] It is noted that references herein to "one embodiment," "an embodiment," "an exemplary embodiment," and the like, indicate that the embodiment being described may include a particular feature, structure, or characteristic, but that all embodiments do not necessarily include that particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in connection with an embodiment, it will be within the knowledge of one of ordinary skill in the art to implement such feature, structure, or characteristic in connection with other embodiments, whether or not explicitly described.

[0023] It should be noted that although this application may refer specifically to cardiac ablation, the embodiments described herein may also be capable of targeting other pathologies with additional energy sources for ablation, including, but not limited to, cryogenic, radio frequency (RF), microwave, laser, ultrasound, and pulsed electric fields.

[0024] Described herein are embodiments of medical systems that use optical signals during and after ablation energy is delivered to create lesions in tissue and characterize changes in the tissue.

[0025] In some embodiments, low coherence interferometry (LCI) and / or spectroscopy can be used in conjunction with the optical signals to provide depth resolved information about the sample tissue being imaged. Although the application portion can focus on the transmission of optical signals through the catheter and portions of the catheter, it should be understood that the embodiments discussed herein can be applied to any medical device that utilizes optical signals.

[0026] Exemplary System Embodiments FIG. 1 illustrates a diagram of an exemplary ablation system, including a catheter 100, a console 101, an ablation energy source 102, a cooling source 103, and a user interface 104. In some embodiments, a distal section of the catheter 100 is positioned in a portion of tissue in a patient 107. In some embodiments, the outer elements of the catheter 100 (e.g., referred to herein as external elements) may be held in a single enclosure or in multiple enclosures as determined by the system design. In some embodiments, the elements in the different enclosures may be connected through external data cables, optical fibers 105, and / or electrical cabling or wires 106. In some embodiments, the system may not include a cooling source 103. In some embodiments, the ablation system may use conventional radio frequency (RF) ablation means to generate thermal lesions in tissue, which may include a cooling source 103 in the form of an irrigation pump to prevent carbonization of the blood. In other embodiments, the ablation system may use pulsed field ablation energy or cryogenic energy, and the cooling source 103 may not be included in the ablation system.

[0027] Exemplary Catheter Embodiments 2 illustrates a catheter 100 according to an embodiment of the present disclosure. The catheter 100 includes a proximal section 200, a distal section 201, and a shaft 202 coupled between the proximal section 200 and the distal section 201. In some embodiments, the proximal section 200 includes a handle for interfacing with a clinical user. The handle can include one or more buttons, sliders, levers, lights, dials, and other elements that allow mechanical and functional control of the catheter shaft 202 and the distal section 201. In some embodiments, the catheter proximal section 200 can also include wiring 204 and one or more connectors 205. The wiring 204 can include a wire harness or grouped cables and optical fibers and / or waveguides. The one or more connectors 205 can serve as an interface for the catheter 100 and can directly or indirectly connect the catheter 100 to other elements of the ablation system, including the ablation energy source 102, the optical source, the console 101, and / or the user interface 104. In some embodiments, the proximal section 200 of the catheter can also have a port for connecting to a cooling source 103. In some embodiments, the wiring 204, wiring harness elements, and the one or more connectors 205 can be detachable from the handle in the proximal section. In other embodiments, communication between the catheter 100 and other elements of the ablation system can be wireless, using technologies such as Bluetooth, WiFi, cellular, etc.

[0028] The proximal section 200 can include additional interface elements by which a user of the catheter 100 can control the operation of the catheter 100. For example, the proximal section 200 can include a deflection control mechanism that controls the deflection angle of the distal section 201. The deflection control mechanism can use mechanical movement of elements on the proximal section 200, or the deflection control mechanism can use an electrical connection to control the movement of the distal section 201. The proximal section 200 can include various buttons or switches that allow a user to control when RF energy is applied at the distal section 201 or when beams of radiation and / or light are transmitted from the distal section 201, allowing for the acquisition of optical data. In some embodiments, these buttons or switches are located on a separate user interface that is coupled to a processing device or on the handle itself.

[0029] The deflection control mechanism can include electrical or mechanical elements designed to provide signals to the distal section 201 to change the deflection angle of the distal section 201. The deflection system allows for the guidance of the distal section 201 by actuating a mechanical control located in the proximal section 200, according to an embodiment. This deflection system can be based on a series of aligned and evenly spaced cutouts in the catheter shaft 202 intended to provide unidirectional or multidirectional deflection of the distal section 201, in combination with wires connecting the deflection mechanism control in the proximal section 200 with the catheter tip 214 in the distal section 201. In this way, a certain movement of the proximal section 200 can be projected to the distal section 201. In some embodiments, a combination of several control wires attached to the catheter tip can allow deflection of the catheter tip along different directions.

[0030] FIG. 2 further illustrates elements of the distal section 201 in an expanded view showing the catheter tip 214. In certain embodiments, the catheter shaft 202 and distal segment can include one or more radiopaque markers 215 for navigation purposes. The distal section 201 can include one or more external electrodes 213 for ablation, according to some embodiments. The electrodes 213 can be distributed over a segment of the catheter's distal section 201 or directly onto the catheter tip 214 at the distal end of the distal section 201. In some embodiments, the distal section 201 of the catheter 100 can also include one or more irrigation orifices 216, if cooling is required. In some embodiments, cooling fluid (e.g., compressible and / or incompressible cooling fluid) provided by the cooling source 103 travels through a channel that runs at least partially through the shaft 202 of the catheter 100 and then exits through the irrigation orifices 216. These irrigation orifices 216 may be located in any segment of the catheter shaft 202, the electrode 213, or the catheter tip 214.

[0031] 3A and 3B illustrate exemplary axial and radial cross-sectional diagrams, respectively, of a distal segment of a catheter according to an embodiment of the present disclosure, illustrating different configurations of electrodes, viewports, and lens-fiber assemblies at the catheter tip.

[0032] As shown in Figures 3A-3B, the distal section 201 and shaft 202 of the catheter can have a single electrode or multiple electrodes 213 for delivering ablation energy. In some embodiments, PFA energy can be used and the electrode 213 configuration can be configured to deliver monophasic or biphasic pulse applications. In some embodiments, if cooling is implemented, the central cooling channel 306 and cooling communication pathway 307 can guide cooling fluid through the shaft 202 to the distal section 201, where such fluid can then be externalized through the irrigation orifices 216 to cool the surrounding tissue or blood.

[0033] The distal section 201 also includes multiple optical viewports 308 capable of transmitting / collecting light at various angles from the distal section 201. In some embodiments, the optical viewports 308 may be distributed across the exterior of the distal section 201, resulting in multiple distinct viewing directions, and in some embodiments, each of the multiple viewing directions are substantially non-coplanar.

[0034] In some embodiments illustrated in FIGS. 3A-3B, light is transported through the shaft 202 and distal section 201 by an optical fiber 105. Such optical fiber 105 may be coated or uncoated. In some embodiments, the optical fiber 105 is coated with a polymer for protection, insulation, and structural integrity. In some embodiments, the optical fiber 105 is attached to a lens 300, which focuses the light, which then passes into the tissue. In some embodiments, the fiber may be mechanically or chemically attached through a glue or adhesive 305. In some embodiments, the glue or adhesive 305 may be selected to provide mechanical strength and also to provide optical index matching. As illustrated in FIG. 3B, in some embodiments, the lens 300 and / or fiber 105 are supported by an internal support structure 304, which allows the lens 300 and fiber 105 to be localized and oriented in the proper location. In other embodiments, the lens 300 may be localized and / or oriented by the configuration of the shaft 202, the electrodes 213, and the catheter tip 214. In some embodiments, the lens 300 may not be an external element to the fiber 105 and may be produced by a curvature fabricated (e.g., etched, machined, laser cut, or chemically formed) directly onto the distal end of the fiber 105 and fiber core. In some embodiments, the distal section 201 may include a substrate with patterned waveguides and optical focusing or directing elements (e.g., lenses and mirrors, etc.) for guiding light to / from each of the multiple optical viewports 308. The substrate may be a flexible or partially flexible substrate made from materials such as polyimide, polyethylene glycol, parylene, or polydimethylsiloxane (PDMS), etc.

[0035] In some embodiments, as shown in FIG. 3A, a lens 300 may be connected to the optical fiber and placed in a recess 303 in the catheter. In some embodiments, the lens may be flush 301 with the catheter surface (e.g., shaft, electrode, or tip) or may extend beyond the surface 302 of the catheter shaft 202, electrode 213, or tip 214. In some embodiments, a lens that is flush 301 with the catheter surface or extends beyond the surface 302 may be a contact point with external tissue. In some embodiments, lenses that are embedded in the catheter and use viewports 308 to allow light to pass through, when cooling is implemented, may also use these same viewports 308 as irrigation orifices 216. In some embodiments, the viewports 308 and irrigation orifices 216 may be separate and distinct elements.

[0036] 4A-4D illustrate diagrams of exemplary two-dimensional (2D) and three-dimensional (3D) geometries of a distal section 201 of a catheter according to an embodiment of the present disclosure. As shown in FIG. 4A-4D, the distal section 201 of the catheter can assume different 2D and 3D geometries. In some embodiments, the 2D and 3D geometries of the distal section can be the actual geometry of the catheter in its unloaded state. In some embodiments, the catheter geometry can be deflected and / or reshaped to temporarily fit within a delivery sheath for easy passage through the vasculature of a patient. In other embodiments, the 2D and 3D geometries of the distal section can be generated from a relatively straight catheter distal section through deformations associated with mechanical or electromagnetic forces controlled from the proximal section 200, such that after passing through at least a section of the vasculature and prior to ablation energy delivery, the distal section forms such 2D and 3D geometries to improve surface contact of the catheter with local anatomical structures.

[0037] As illustrated in FIGS. 4A-4D, such 2D or 3D geometries can have electrodes 213 placed at different locations in the catheter to maximize electrode contact and optical access to anatomical structures where ablation may be required (e.g., tissue ablation sites). In some embodiments, the electrodes 213 and other components of the catheter can have a configuration similar to FIG. 3 with lenses / optical viewports located through the shaft 202, distal segment 201, or tip 214. In some geometries, the distal section 201 of the catheter 201 (as shown in FIG. 4B) can have at least a partial loop configuration 401 during ablation. In some embodiments, geometries with loop configuration 401 can be beneficial during peripheral ablation around arteries and veins in the vasculature. In some embodiments, the radial petal configuration 400 shown in FIG. 4A can extend outward for better contact with surrounding tissue. In other embodiments, a 3D sphere configuration 402 (as shown in FIG. 4C), a cone, a cylinder, or other irregular shape configuration can be expanded from the surface of the distal section 201 to increase its overall diameter for better tissue engagement. In some embodiments, such expanded geometries can be beneficial when ablating tissue in the interior diameter or vasculature, or in defined tissue cavities or chambers inside or on the surface of the human body. In some embodiments, the expanded 3D geometry configuration shown in FIG. 4C can be generated through mechanical deflection by using a balloon, rod, wire, or other mechanical element to change the geometry of the distal section 201. In some embodiments, a shape memory material (e.g., shape memory metal alloy (e.g., Nitinol, etc.) or shape memory polymer, etc.) can be used to generate such geometries / configurations.Other embodiments of the 3D structure of the distal section can include a helical structure 403, 404, as shown in FIG. 4D. In some embodiments, the helical structure 403, 404 can be used to ablate the inner lumen or cavity of the vasculature. In some embodiments, the distal section 201 geometry of the catheter can be implemented during ablation using conventional RF, PFA or cryogenic energy. In some of the exemplary embodiments described above in which the distal section 201 changes geometry during the procedure, there can be a mechanism that allows relative movement of the optical fiber 105 (which tends to be axially rigid) relative to the distal section 201 or shaft 202, to prevent unwanted tethering or bending of the optical fiber 105 and possible mechanical failure.

[0038] In some embodiments, the catheter can include some or all of the following elements interconnecting the proximal section 200 with the distal section 201, including but not limited to a shaft, irrigation channels, RF conductive media, deflection mechanisms, electrical connections, and optical transmission media. In some embodiments, the electrical connections can be used to provide signals to optical modulation components or to ablating elements located in the distal section 201. In some embodiments, one or more optical transmission media can guide light generated from an optical source (e.g., exposure light) toward the distal section 201, while another subset of optical transmission media guides light returning from the distal section 201 (e.g., scattered or reflected light) back to the proximal section 200. In some embodiments, the same one or more optical transmission media guide light in both directions. In some embodiments, the optical transmission medium includes polarization maintaining (PM) fiber or single mode fiber, multimode fiber, or a waveguide (single mode or multimode). In some embodiments, the same optical transmission medium is used to transport both the exposure light and the light returning from the tissue (scattered or reflected) through at least a section of the length of the catheter, resulting in a bidirectional communication path.

[0039] In some embodiments, the distal section 201 of the catheter can include other elements, such as one or more thermal sensors, pressure sensors, force sensors, electrical sensors, optical splitters, optical mirrors, multiplexers, and the like. In some embodiments, optical interferometer or RF energy source elements may also be included in the proximal section 200 / handle of the catheter. In some embodiments, most or all of the energy source 102 and optical interferometry elements may be included in elements external to the catheter, such as the external ablation energy source 102, console 101, or user interface 104. In some embodiments, the console 101, energy source 102, and user interface 104 may be included in a single enclosure or multiple enclosures.

[0040] Exemplary embodiments of ablation energy circuits In some embodiments, the ablation energy circuit can include an ablation energy source 102 and electrical transport elements (e.g., wires and cables, insulating elements, switches, resistors, capacitors, transformers, modulation elements, connectors, and electrodes, etc., as needed), such that the energy source can deliver electrical energy that is transported through the catheter through the electrodes and into the tissue to ablate and create a lesion. In some embodiments, the ablation energy is delivered through a pulsed field for a PFA system. In some embodiments, the frequency, amplitude, duration, and other characteristics of the electromagnetic pulse can be selected by the clinician prior to delivering the selected pulse therapy at the selected ablation site. In some embodiments, PFA can be delivered in a biphasic or monophasic manner. In some embodiments, the PFA energy pulses can be synchronized with the cardiac rhythm by sensing cardiac electrical signals (e.g., QRS complexes) using an ECG / EKG or other sensing means, and then using the cardiac signal as a reference to deliver the synchronized PFA energy pulses to the selected ablation site in the heart.

[0041] Exemplary embodiments of optical circuits 5 illustrates a diagram of an exemplary optical circuit 500, according to an embodiment of the present disclosure. In some embodiments, the elements of the optical circuit 500 illustrated in FIG. 5 are present within the catheter 100 and also present as external elements (e.g., external to the catheter 100). In some embodiments, the external elements of the optical circuit 500 may be housed in multiple or a single enclosure. In some embodiments, the external elements of the optical circuit 500 are housed within the console 101, which may or may not be housed in the same enclosure as the user interface 104 and the ablation energy source 102.

[0042] The optical circuit 500 comprises an optical source 502, which may include one or more laser diodes or light emitting diodes (LEDs). For example, LEDs may be used when performing time-domain and / or spectral-domain analysis, while tunable lasers may be used to sweep the wavelength of light over a range of wavelengths. The beam of radiation generated by the optical source 502 may have a wavelength in the infrared range (e.g., 750 nm to 1 mm), while other optical sources 502 may work in the visible range (e.g., 400 nm to 750 nm) or the ultraviolet range (e.g., 400 nm to 10 nm). In an example, the beam of radiation has a central wavelength between 1000 nm and 1600 nm. The optical source 502 may be designed to output a beam of radiation at only a single wavelength, or it may be a swept source and designed to output a range of different wavelengths. The range of wavelengths can include any wavelength found in the near infrared or mid infrared spectral range. The generated beam of radiation can be guided towards the distal section 201 via an optical transmission medium connected between the proximal and distal sections 200 and 201 in the shaft 202. Some examples of optical transmission media include single mode and multimode optical fibers, as well as integrated optical waveguides. In some embodiments, the electrical and optical transmission media are provided by the same hybrid medium that allows for the propagation of both electrical and optical signals.

[0043] In some embodiments, the optical circuit 500 includes one or more components of an interferometer to perform LCI using light generated from an optical source. In some embodiments, in performing LCI, the optical circuit 500 is capable of analyzing interferometer data. Interferometer data analysis can be associated with understanding changes in the polarization state of light reflected or scattered by tissue, which can allow for evaluation of changes in tissue birefringence. In some embodiments, the optical transmission medium used to guide light to and from the distal section 201 may not affect the state and degree of polarization of the light (e.g., single mode optical fiber). In other embodiments, for such LCI circuits, the optical transmission medium can affect the polarization in a constant and reversible manner. In further embodiments of the optical circuit 500, the optical analysis of light reflected or scattered back by tissue can include methods associated with tissue spectroscopy. By tissue spectroscopy, the optical transmission medium used to guide light to and from the distal section 201 can allow multiple modes of light (e.g., multimode optical fiber, etc.). In further embodiments of the optical circuit 500, both single mode and multimode fibers may be used to determine different paths from one or more optical sources to the distal section 201 and back, allowing both LCI and spectroscopy methods to be used by the system to better control the ablation procedure.

[0044] Various embodiments of the present application include an LCI system integrated into a medical device, such as a catheter 100 for optical interrogation of a sample 510 (e.g., at an ablation tissue site). In some embodiments, the LCI system may be implemented by an optical circuit 500, which may be referred to herein as an LCI system. The optical circuit 500 may include a delay unit 512, which may include various light modulating elements. These modulating elements may perform phase and / or frequency modulation to counteract undesirable optical effects in the light and to select one or more depths of the sample to be imaged. Use of the term "light" may refer to any range of the electromagnetic spectrum. In certain embodiments, the term "light" refers to infrared radiation.

[0045] The optical circuit further includes a splitting element 504, a sample arm 506, a reference arm 508, and a detector 514. In the embodiment shown, the delay unit 512 is positioned in the reference arm 508. However, it should be understood that the delay unit 512 may instead be positioned in the sample arm 506. Alternatively, various elements of the delay unit 512 may be present in both the sample arm 506 and the reference arm 508. For example, elements of the delay unit 512 that introduce a variable delay to the light may be positioned in the sample arm 506, while elements that modulate different polarization modes of the light may be positioned in the reference arm 508. In another example, elements of the delay unit 512 that modulate different polarization modes of the light may be positioned in the sample arm 506, while elements that introduce a variable delay to the light may be positioned in the reference arm 508. In one example, the sample arm 506 and the reference arm 508 are optical waveguides (e.g., patterned waveguides or optical fibers). In one embodiment, all of the components of the LCI system are integrated onto a planar lightwave circuit (PLC). In another embodiment, at least the components in the delay unit 512 are integrated onto the same substrate of the PLC. Other implementations are possible as well, such as, for example, fiber optic systems, free space optical systems, photonic crystal systems, etc.

[0046] It should be understood that the LCI system can include any number of other optical elements not shown for clarity. For example, the LCI system can include mirrors, lenses, gratings, splitters, micromechanical elements, etc. along the path of the sample arm 506 or the reference arm 508.

[0047] The splitting element 504 is used to direct the light received from the optical source 502 to both the sample arm 506 and the reference arm 508. The splitting element 304 can be, for example, a bidirectional coupler, an optical splitter, an adjustable splitting ratio coupler, an optical switch, or any other modulating optical device that converts a single beam of light into two or more beams of light. In some embodiments, the splitting element 504 splits the light into one or more reference arms and multiple sample arms such that the light / radiation from the multiple sample arms can optically interrogate samples at different locations or directions in the distal section 201. In some embodiments, a first splitter element directs the light into the reference arm 508 and the sample arm 506, and a second splitter element can further split the sample arm 506 into multiple beams. It will be appreciated that any combination of one or more splitter elements 504 in different parts of the radiation / light path can be used to generate multiple beams for referencing and interrogating the sample as required by the optical analysis procedure.

[0048] The light traveling the sample arm 506 eventually impinges on the sample 510. The sample 510 can be any suitable sample to be imaged (e.g., tissue, etc.). The light scatters and reflects back from various depths in the sample 510, and the scattered / reflected radiation is returned to and collected in the sample arm 506. In another embodiment, the scattered / reflected radiation is returned to and collected in a waveguide different from the transmission waveguide. The scan depth can be chosen via a delay imposed on the light in the delay unit 512.

[0049] The light in the sample arm 506 and the reference arm 508 is recombined before being received at the detector 514. In the embodiment shown, the light is recombined by the splitting element 504. In another embodiment, the light is recombined in an optical coupling element different from the splitting element 504. The detector 514 can include any number of photodiodes, charge-coupled devices, and / or CMOS structures and convert the received light into an electrical signal. The electrical signal includes depth-resolved optical data related to the sample 510 and can be received by a processing module. The processing module has an interface that converts such electrical signals into digital data that can then be processed and analyzed by a standard processing unit (e.g., a computer, a data processor, reprogrammable hardware, an ASIC, or any other type of digital data processing circuit or system, etc.).

[0050] As used herein, the term "depth resolved" defines data in which one or more portions of the data can be identified that relate to a particular depth of the sample being imaged. The LCI system is illustrated, according to an embodiment, as an interferometer design similar to a Michelson interferometer. However, other interferometer designs are possible as well, including Mach-Zehnder or Mireau interferometer designs.

[0051] Exemplary embodiments of the external elements of the system As illustrated in FIG. 1, some elements of the system can be external to the catheter 100 and can be directly or indirectly connected to the catheter 100. Such elements can be included in multiple enclosures or in a single enclosure. In the configuration illustrated in FIG. 1, the console 101, the user interface 104, and the ablation energy source 102 are housed in separate enclosures. In some embodiments, a portion of the optical circuit 500 is encapsulated in the console 101 and a portion is encapsulated in the catheter 100. In further embodiments, the ablation energy source 102 can also be encapsulated in the console 101. Elements of the user interface 104 can be enclosed in the console 101 and other elements can be enclosed in the display module. In some embodiments, the external elements of the system also include a processing module, which can be encapsulated in combination with any of the other external elements (e.g., in the console 101). The processing module can include some of the elements of the optical circuit 500 or simply receive signals from the optical circuit 500. The processing module also includes additional circuitry and can measure the signal generated at the optical detector 514 and use it to produce data that can be further processed and analyzed. In some embodiments, the processing unit of the processing module, other elements of the processing module, catheter 100, ablation energy source 102, and console 101 can be directly or indirectly connected to a user interface 104. The user interface 104 can provide audio, visual, and / or tactile data to the user to inform the user of the characteristics of the sample 510 and the status and treatment variables of the ablation system before, during, and / or after ablation energy is delivered.The data provided by the user interface 104 can be used by clinicians to make better informed decisions about ablation treatments.

[0052] Exemplary embodiments of determining tissue birefringence Birefringence is an optical property of a material that is related to the polarization and propagation direction of light. Most viable human soft tissues are generally considered to be birefringent (e.g., myocardial, kidney, and brain tissues, etc.). This birefringence originates from the organization and geometry of their internal components and structures. In particular, the organization and geometry of proteins and / or the organization and alignment of cells within the tissue are important determinants of tissue birefringence. When some of the internal proteins of a tissue move from a normal state to a denatured state, the optical birefringence changes in the tissue because the geometry of the proteins themselves and their arrangement within the matrix changes. Collagen, elastin, and fibrin are extracellular matrix proteins that, when denatured, can affect the birefringence properties of the tissue. This is because light reflected or scattered from such extracellular matrices can have a different polarization state (e.g., polarization and phase retardation) compared to the optical signal received when these proteins are in their normal state. Additionally, other proteins in the cell membrane and intracellular cytoskeleton when denatured can also generate changes in the polarization state of light when denatured or when the geometry of the cell membrane or cytoskeleton changes, affecting the anisotropy of the tissue.

[0053] Exemplary embodiments of RF ablation and determining tissue birefringence By using an RF catheter or other medical delivery device, RF energy can be delivered into the tissue, causing heating. After the tissue reaches approximately 50°C, permanent thermal lesions can occur through necrosis. Protein denaturation can occur at approximately 70°C. Thus, the catheter system as described herein uses polarization-sensitive LCI to interrogate the optical state of the ablated sample, allowing direct visualization in real time by analyzing the reflected and scattered light signals, as well as their polarization state and phase delay, with additional information of the time of flight, frequency, and amplitude of the light signals, as the tissue reaches 70°C in a depth-resolved manner. In additional embodiments, predictive algorithms using extrapolation, statistical fitting, interpolation, or artificial intelligence (e.g., machine learning) can be applied to the lesion library to better predict the geometry of the permanently ablated lesion (e.g., the width, length, and / or depth of the lesion). In some embodiments, the algorithm can take into account the geometry of the directly visualized lesion to reach 70°C and calculate the geometry of the tissue sample to reach 50°C. The geometry of the lesion that reaches 50° C. determines the area of ​​permanently ablated tissue that will not have cardiac rhythm electrical conductivity. Determining and visualizing such geometry allows the clinician to assess whether the lesion has completely penetrated the tissue wall or reached the desired structures at the site of ablation, and whether gaps exist in the ablation line.

[0054] In some configurations of optically guided ablation systems, the penetration depth of light (that can be used for direct visualization) and its extrapolation of the lesion size at 50°C may not be sufficient to determine complete penetration into the tissue wall. In such cases, mathematical algorithms may be used to predict lesion size when the ablation time at that particular lesion must exceed the time it takes to reach a birefringence change at the maximum depth of light penetration used for direct optical assessment in the tissue. Experiments using the systems described herein have shown that the ratio of total ablation time to time to degeneration may be a key predictor of lesion size when used in statistical fitting algorithms (e.g., interpolation, extrapolation, regression, least residual, ANOVA, MANOVA, etc.) or artificial intelligence algorithms (e.g., machine learning). In some embodiments, the time to degeneration may be defined as the time required to reach degeneration at 70°C at a known depth. In some embodiments, the known depth used may be the maximum depth for the resolvable optical signal to be analyzed for polarization depth change, which may be approximately 1.5 mm for infrared / near infrared. Thus, the processing unit of the optically guided ablation system can be used in combination with such algorithms to predict lesion depth beyond that for direct visualization in real time and transmit such information to the clinician through the user interface 104.

[0055] Exemplary embodiments of methods for determining birefringence of PFA and tissue Pulsed field ablation (PFA) uses electromagnetic pulses to generate lesions in tissue during the ablation process. Typically, PFA pulses are applied across two electrodes at a time, spaced relatively closely over a segment of tissue where a lesion is desired. A series of high voltage pulses (either monophasic or biphasic) are imposed across the electrodes, briefly exposing the tissue between them to a high intensity electric field. In some embodiments, the series of pulses may be referred to herein as a pulse train. In some embodiments, clinical applications and protocols for PFA may be aimed at generating non-thermal lesions through cell apoptosis or other types of non-necrotic delayed cell death, where the energy density, intensity, and overall strength of the pulse train are sufficient to cause cell / tissue necrosis through thermal injury.

[0056] During clinical protocols for PFA, a pulse train of known frequency, amplitude, and duration is applied between two or more electrodes (e.g., in contact with or in close proximity to tissue) at the ablation site, causing pores to open in the cell membranes of cells in the targeted tissue segment. Such pores cause cell edema, and if such edema is sufficient, apoptosis (or other delayed cell death) mechanisms are activated in the cells, leading to subsequent cell death. Thus, polarization-sensitive LCI methods directed at determining changes in tissue birefringence due to protein denaturation at 70° C. may not be sufficient when using PFA, because that temperature may not be reached in the tissue or only a minimal surface area of ​​the tissue in direct contact with the electrodes may undergo denaturation and necrosis. In some embodiments, all or the majority of the interrogated tissue sample may undergo delayed cell death due to non-thermal damage.

[0057] Experiments using the polarization-sensitive LCI ablation system described herein have shown sensitivity to changes in tissue birefringence associated with application of a PFA energy train in the absence of thermal damage. FIG. 6 illustrates diagrams of exemplary experimental histological images of myocardial tissue 600 for non-ablated samples and samples after PFA ablation according to embodiments of the present disclosure. In particular, FIG. 6 shows histological results comparing non-ablated tissue and PFA-ablated tissue, which showed changes in birefringence in the polarization-sensitive LCI system. After the PFA ablation train is applied, the pulses cause disruptions in cell membranes and cell membrane proteins, leading to cell edema and subsequent apoptosis (delayed cell death) due to loss of tissue integrity and structure, as shown in FIG. 6.

[0058] Myocardial tissue sample 600 shows two adjacent areas with two very different structures. The non-ablated area 601 shows organized, tightly packed cellular structures supported by cell membranes, intracellular cytoskeleton, and extracellular matrix. The PFA-ablated tissue 602 sample shows completely disrupted cell membranes and intracellular cytoskeleton, cell nuclei 604 outside such membranes, and enlarged gaps 603 in the cellular structures and extracellular matrix.

[0059] Proteins and structures responsible for maintaining and organizing cellular structures, and thus tissue anisotropy (e.g., birefringence), include extracellular matrix (e.g., collagen, elastin), cytoskeleton / flagellum or cilia (e.g., tubulin, actin, or lamin), and cell membrane proteins (e.g., integral / transmembrane proteins). In some embodiments, PFA-ablated tissue samples 602 showed birefringence changes in the LCI system after ablation. For different PFA ablation lesions during the experiment, birefringence changes were observed within seconds (e.g., less than 30 seconds) or minutes (e.g., up to 40 minutes) after delivery of PFA energy (e.g., pulse train) to the tissue. The time for detection of birefringence changes depends on the intensity (e.g., pulse amplitude), type (monophasic, biphasic), frequency (e.g., pulse frequency), and duration of the pulse train (e.g., total time for all pulses to be delivered to the tissue).

[0060] In some embodiments, the delayed change in birefringence may be a delayed apoptosis / delayed cell death / remodeling response rather than an immediate necrotic mechanism. The delayed change in birefringence may be associated with a delayed change (reduction) in anisotropy of tissue structure. As seen in the histology of PFA-ablated tissue 602, structural integrity as well as geometric and organizational changes are seen at the tissue and cellular level. The organization in the non-ablated sample 601 of the cellular structure with organized matrix determines the anisotropy of the tissue, which is lost after PFA ablation (as shown in sample 602) due to subsequent cell death after apoptosis and cell edema. Thus, the loss of tissue anisotropy after PFA ablation and subsequent cytoskeleton breakdown, protein denaturation, or fragmentation leads to a loss of birefringence, which may be detectable due to the change in polarization and phase retardation by the LCI optically guided ablation system. The apoptotic process from cell edema may directly affect the intracellular cytoskeleton, its structural proteins, such as tubulin (a protein component of microtubules), actin (a component of microfilaments), and lamins (a component of intermediate filaments), and its connections to the extracellular matrix. Disruption of such connections between the cytoskeleton and the extracellular matrix may lead to a global loss of structure and organization of the tissue segment. Thus, loss of cytoskeletal integrity may be a major factor leading to the loss of anisotropy and birefringence on tissues that can be detected by the LCI methodology described herein.

[0061] Exemplary embodiments of an optically guided PFA procedure for cardiac ablation In some embodiments, for use of an optically guided PFA system for cardiac ablation, the catheter 100 is introduced into the human vasculature, either directly or through an access sheath. The distal section 201 of the catheter is moved to the site of ablation using a guidewire, an access sheath, a steerable sheath, or deflection of the catheter 100 itself. At the ablation site (e.g., atrium, ventricle, artery, vein, etc.), at least one or more electrodes 213 on the surface of the catheter distal section 201 are placed in direct contact with tissue at the ablation site. Contact or contact stability can be established between the distal section 201 and the tissue ablation site using light or other forms of radiation emitted by an optical source, which travels at least partially through the PM optical transmission medium to the distal section 201 of the catheter 100. After contact or contact stability is established, a PFA pulse train can be transmitted to the tissue, where the characteristics of the pulse train (e.g., frequency, amplitude, intensity, or duration) are determined by the clinical user. During and / or after delivery of the ablation pulse train, changes in the birefringence of the interrogated tissue can be monitored through evaluation of changes in the polarization state and phase delay of the reflected / scattered optical signal sent into the tissue through the catheter 100. If no change or reduction in birefringence is detected within a predetermined time frame (e.g., 1 second to 1 hour), the clinician can re-ablate the tissue using a pulse train with the same or different characteristics.

[0062] In some embodiments, mathematical, statistical, or artificial intelligence predictive algorithms or equations (which use measures of time to loss of birefringence or change / difference in the amount of birefringence in ablated tissue) may be used to predict whether a PFA lesion is permanent and thus correlated with the probability of recurrence of cardiac fibrillation. Such algorithms may be used by clinicians to determine the need to re-ablate tissue at selected ablation sites. In some embodiments, such predictive algorithms may be programmed directly into the ablation system and the results may be communicated to the clinician through the user interface 104, or such algorithms or equations may be provided to the clinician for their offline use.

[0063] In other embodiments of the ablation procedure, prior to establishing tissue contact at the ablation site, the distal section 201 of the catheter 100 may undergo geometric changes to generate 2D and 3D structures equivalent to, but not limited to, those shown in Figures 4A-4D to provide better contact or to adapt the catheter to the local anatomical structures.

[0064] In some embodiments of the PFA optically guided ablation procedure, the catheter may be held in place for a predetermined amount of time required after ablation, where birefringence changes are expected to occur. In other embodiments of the procedure, after ablation, the catheter 100 is moved to another ablation site in the body. After a predetermined amount of time, the catheter 100 is moved back to the first ablation site to monitor whether the PFA pulses have generated a change in the birefringence of the tissue. In further embodiments, the catheter may be removed from the body and the same catheter 100 or another similar catheter may be reused at a later reintervention and moved again to the first ablation site to monitor whether the tissue exhibited a change in birefringence due to the initial PFA pulse train.

[0065] Exemplary embodiments of an optically guided renal denervation procedure In some embodiments, for use of an optically guided ablation system for renal denervation, a catheter 100 is introduced into the human vasculature, either directly or through an access sheath. A distal section 201 of the catheter is moved to the site of ablation (e.g., a renal artery) using a guidewire, an access sheath, a steerable sheath, or deflection of the catheter 100 itself. At the ablation site (e.g., a renal artery), at least one or more electrodes 213 on a surface of the catheter distal section 201 are placed in direct contact with tissue at the ablation site. Contact or contact stability can be established between the distal section 201 and the tissue ablation site using light or other forms of radiation emitted by an optical source, which travels at least partially through the PM optical transmission medium to the distal section 201 of the catheter 100. After contact or contact stability is established, RF energy can be transmitted to the tissue, where the characteristics of the RF energy (e.g., power, duration, etc.) are determined by the clinical user. During delivery of the ablative RF energy, changes in the birefringence of the interrogated tissue may be monitored through evaluation of changes in the polarization state and phase delay of the reflected / scattered optical signal sent through the catheter 100 into the tissue. RF energy may be applied until the tissue is ablated to the desired depth, as predicted by an algorithm or equation in the system (which uses the time to degeneration, or the ratio between the total ablation time and the time to degeneration, as a predictor variable). In some embodiments, the catheter may be moved as necessary to complete the ablation through the complete circumference of the renal artery.

[0066] In some embodiments of the optically guided ablation method for renal denervation, the user can move the catheter to the ablation site and use an optical signal to re-interrogate the tissue and determine the birefringence loss through the periphery to ensure that no gaps are present.

[0067] In other embodiments of an ablation procedure for renal denervation, prior to establishing tissue contact at the ablation site, the distal section 201 of the catheter 100 may undergo geometric changes to generate 2D and 3D structures equivalent to, but not limited to, those shown in Figures 4A-4D to provide better contact or to adapt the catheter to the local anatomical structures.

[0068] In some embodiments of the renal denervation procedure described above, radiation / light traveling at least partially through a multimode optical transmission medium (multimode fiber or waveguide) may be used prior to delivery of ablation energy, and the light is processed and analyzed using optical spectroscopy methods to determine the depth at which the renal nerve is located relative to the renal artery wall. In some embodiments, the system includes both independent single-mode and multimode optical paths, making it possible to use both LCI and spectroscopy in the same ablation catheter system. In some embodiments, ultrasound technology may also be added to the LCI catheter. In such an exemplary ultrasound technology catheter, ultrasound signals may be used to determine the depth of the renal nerve prior to ablation.

[0069] Exemplary embodiments of optically guided ablation for the treatment of epilepsy In some embodiments, regarding the use of an optically guided ablation system for the treatment of epilepsy, the catheter 100 is introduced into the human vasculature directly or through an access sheath. The distal section 201 of the catheter is moved to the site of ablation using a guidewire, an access sheath, a steerable sheath, or deflection of the catheter 100 itself. At the ablation site (e.g., a discrete epileptic focus), at least one or more electrodes 213 on the surface of the catheter distal section 201 are placed in direct contact with the tissue at the ablation site. Contact or contact stability can be established between the distal section 201 and the tissue ablation site using light or other forms of radiation emitted by an optical source, which travels at least partially through the PM optical transmission medium to the distal section 201 of the catheter 100. After contact or contact stability is established, RF energy can be transmitted to the tissue, where the characteristics of the RF energy (e.g., power, duration, etc.) are determined by the clinical user. During delivery of the ablative RF energy, changes in the birefringence of the interrogated tissue can be monitored through evaluation of changes in the polarization state and phase delay of the reflected / scattered optical signal sent through the catheter 100 into the tissue. RF energy can be applied until the tissue is ablated to a desired depth, as predicted by an algorithm or equation in the system (which uses the time to degeneration, or the ratio between the total ablation time and the time to degeneration, as a predictor variable). In some embodiments, the catheter can be moved to other epileptic foci as desired, and the ablation step repeated.

[0070] 7 illustrates an exemplary method for clinical use of an optically guided pulsed field ablation (PFA) system according to an embodiment of the present disclosure. In some embodiments, the method can include inserting a catheter into a patient's body, navigating to a tissue ablation site, and establishing contact with the tissue ablation site using an optical signal transmitted through the catheter into the tissue. The method further includes sending a PFA electromagnetic pulse train through the catheter to the tissue, and monitoring for changes in the tissue using an LCI optical system by monitoring for changes in polarization and / or phase delay of the optical signal.

[0071] Exemplary embodiments of pulsed field ablation catheters with integrated optics As described herein, the catheter device can be configured to deliver pulsed field ablation (PFA). A particular application includes PFA delivered to the left atrium of the heart in a non-invasive procedure to treat atrial fibrillation.

[0072] Typically, PFA pulses are applied across two electrodes at a time, spaced relatively closely over a segment of tissue where a lesion is desired. A series of high voltage pulses (either monophasic or biphasic) are imposed across the electrodes, briefly exposing the tissue between them to a high intensity electric field. The pulse train can be on the order of 500-1500 Vpp (voltage peak-to-peak) and can be centered around zero volts (biphasic) or single ended going from zero to the peak voltage. In some cases, the pulses can be square or sinusoidal, each pulse typically being of 10-100 microseconds in duration, with between 10 and 25 pulses applied at intervals between 0.5 and 2 seconds. The electric field (and thus the resulting lesion in the tissue) can extend from one electrode to the other. The lowest current density in the lesion zone will be at the midpoint between the electrodes, with current density increasing as one approaches either electrode. The electric field is intended to cause irreversible electroporation of the cells therein, which ultimately results in delayed cell death. Depending on the location of the cells within the field, the delayed cell death can be processed through apoptosis, pyroptosis, necroptosis, and the like.

[0073] When delivered correctly, PFA has been shown to effectively ablate tissue at selected locations, creating permanent lesions that prevent spurious electrical signals from propagating further across the atrial wall into the heart, preventing further unwanted fibrillation. However, if the PFA pulse is not optimally delivered, the lesion may be incomplete and fail to interrupt the spurious signals, resulting in remodeling that leads to subsequent resumption of fibrillation (e.g., sometimes as long as years after the procedure). Suboptimal PFA delivery can result from a number of causes, including improper positioning of the electrodes, insufficient electrode contact, contact movement during delivery, or an inappropriate combination of pulse train parameters (e.g., voltage, current, pulse width, number of pulses, pulse duration, decay time, monophasic vs. biphasic modality, etc.). If a deficiency in any of these parameters leads to resumption of fibrillation days or years after the procedure, a second procedure may be required, exposing the patient to additional risks and incurring additional costs.

[0074] Medical catheters can also include optical systems that use optical coherence reflectometry (OCR) to sense parameters such as endocardial wall contact, tissue viability, lesion formation, and lesion depth and width, among others. OCR methods can include measuring reflection amplitude, birefringence, degree of polarization, and the like, to determine contact quality, cell status, and lesion dimensions. Some devices incorporate micro-optics in the catheter to probe the target tissue and a fiber optic cable that extends through the catheter and connects proximally to an external console that provides optical sources and receivers, switches, reference arms, control electronics, data processing, and display. However, current optical devices are generally directed to combination optical and electrical catheters that use radio frequency ablation (RFA) rather than PFA.

[0075] Thus, there is an unmet need for reliable devices and methods that increase the probability of creating permanent lesions by PFA during a single minimally invasive surgical procedure. The means should enable the physician performing the procedure to assess in real time during the procedure (i) the contact between the stimulation electrodes and the target anatomical structure, and (ii) the effectiveness of the ablation (including the depth and area of ​​the lesion) after stimulation is applied. If insufficient contact is detected, the physician can reposition the catheter before applying energy to the catheter electrodes. If insufficient lesion depth or width is detected, the physician can apply additional PFA pulses to the area in question until a satisfactory lesion is observed. These assessments would enable the physician to create and verify an effective lesion without interruption at the time of surgery, thus reducing the risk of fibrillation recurrence and reducing repeat procedures.

[0076] Typically, PFA pulses are applied across two electrodes at a time, spaced relatively closely over the segment of the atrial wall where the lesion is desired. This is typically in the atrial wall area surrounding each of the four pulmonary vein ostia. A series of high voltage pulses (either monophasic or biphasic) are imposed across the electrodes, briefly exposing the tissue between them to a high intensity electric field. In an exemplary embodiment, the pulse train can be on the order of 500-1500 Vpp, and can be centered around zero volts (biphasic) or single ended, ranging from zero to peak voltage. The pulses can be rectangular, each pulse typically being of 10-100 microseconds in duration, with between 10 and 25 pulses applied at intervals between 0.5 and 2 seconds. The electric field (and thus the resulting lesion) will extend from one electrode to the other. The lowest current density in the lesion zone will be at the midpoint between the electrodes, with current density increasing as one approaches either electrode. The electric field is intended to cause irreversible electroporation of the cells therein, which ultimately leads to apoptosis.

[0077] To optically assess the lesion, at least one optical viewport may be placed at a precisely known point (either the midpoint or some other point) in the space between the electrodes. In practice, such placement is difficult due to the precision limitations of location visualization systems (e.g., fluoroscopy, ultrasound, RF-based, or other mapping / navigation systems, etc.).

[0078] Depending on the particular optical measurement technique and electrical stimulus selected, there may be a time lag between the application of the voltage and the appearance of a detectable change in the ablated cells. This time lag may last anywhere from 30 seconds to 30 minutes. Once the electrical stimulus is applied, it may be necessary to hold the device in the same location during the time lag to observe the desired change and to confirm successful or unsuccessful ablation.

[0079] FIG. 8 illustrates an exemplary distal end diagram of a PFA-OCR catheter having a circular shape, according to an embodiment of the present disclosure. At its distal end, an embodiment of the PFA-OCR catheter 800 (shown in FIG. 8) can resemble a typical circular mapping catheter in appearance. Although a circular shape is shown as an exemplary embodiment, the catheter distal section can be configured as a circle, an oval, or any polygon or combination of polygons. The shape can be configured to surround the pulmonary vein ostium and deployed through the delivery catheter. FIG. 8 provides a front view looking into the pulmonary vein ostium, with the pulmonary vein extending into the plane of the page. In some embodiments, the delivery catheter can be size 8 Fr or smaller (e.g., 2.66 mm or smaller). The circular distal end body 801 of the catheter 800 can be formed from a non-conductive polymer (e.g., polyvinyl chloride (PVC), polyamide, or PeBax®, etc.). The body 801 can have metal electrodes 802 that are uniformly spaced along its length and made from a biocompatible material (e.g., platinum, platinum iridium, gold, or stainless steel, as well as other metals or metal platings). The catheter 800 shown in FIG. 8 illustrates eight electrodes, but the device can have between 24 and 32 electrodes 802. The electrodes 802 are outside the polymer body 801 and are exposed to allow for contact with the endocardial wall. The electrodes 802 can partially or completely surround the body 801, but can have a sufficient area to contact the vessel wall, taking into account surface irregularities. Inside the lumen in the body 801, each electrode 802 can be attached to a wire that can extend down the shaft of the catheter, with the wire terminating in an electrical connector at the proximal end. The connector can be plugged into a dedicated console that provides electrical and optical energy to the catheter and senses the optical and electrical signals returning from the catheter.

[0080] Between each pair of adjacent electrodes 802 is an optical port 803, which may be configured as an opening on the side of the body 801 that faces the endocardium (the back side of the body 801 in FIG. 8). FIG. 8 shows eight optical ports 803 for illustrative purposes, but any number of port counts may be used. In some embodiments, any number of optical ports 803 and electrodes 802 may be placed in any configuration, so long as the ports 803 are not in the same location as the electrodes 802, with a minimum of two electrodes 802 and one port 803. In some embodiments, the optical ports 803 may be referred to herein as orifices or openings formed in the catheter body 801 (e.g., openings 803A and 803B as shown in FIG. 9).

[0081] FIG. 9 provides an enlarged cross-sectional side view of the distal tip of the circular distal end of catheter 800. For clarity, it is shown in a straight, uncurled position as it is contained within its delivery catheter (not shown). When deployed, the distal end of catheter 800 is positioned with the distal plane of its circular shape in contact with endocardial wall 901, as in FIGS. 8 and 9. The exterior of catheter body 801 is provided with electrodes 802A and 802B, with additional electrodes 802 spaced along body 801 (shown in FIG. 8, but not shown in FIG. 9). Electrode 802B is shown cut away, but could completely or partially surround the exterior surface of body 801. The electrodes 802 are positioned on body 801 such that at least a portion of each electrode 802 faces the distal plane of the circular shape of body 801 and contacts wall 901 when a gentle force is applied to the catheter.

[0082] Inside the catheter body 801, at least one wire lumen 902 can extend the length of the catheter. Holes, squives, or slots spaced along the wire lumen 902 can allow passage of electrical wires to connect to each of the electrodes 802. The electrode wires (not shown) can extend the length of the wire lumen 902 and can terminate in an electrical connector at the proximal end of the catheter (not shown). The wires can be attached to the electrodes 802 by soldering, crimping, wedge bonding, ultrasonic welding, laser welding, conductive epoxy, or other means. In one embodiment, each electrode 802 is attached to a dedicated wire, allowing each electrode 802 to be accessed in the same way by control circuitry in the console (not shown). The console electronics can use the electrodes 802 for several functions: (i) to apply PFA stimulation, (ii) to measure electrogram signals, (iii) to interface with a navigation or mapping system, or (iv) to measure tissue impedance. The electrodes 802 may be multi-purpose across several of these functions or may be dedicated to a single function. The set of electrodes 802 can include any combination of single-use or multi-use electrodes.

[0083] In an alternative embodiment, multiple electrodes 802 can be connected together in parallel to form a single node. For example, referring to the electrodes 802 in FIG. 8, a user can move sequentially around the circle in a counterclockwise direction and connect every other electrode 802 together. Thus, the first, third, fifth, and seventh electrodes 802 can form one node, and the second, fourth, sixth, and eighth electrodes 802 can form a second node. In this configuration, a PFA stimulation event can use the even numbered electrodes 802 as one pole and the odd numbered electrodes 802 as the other pole, thus ablating the entire circular area at once.

[0084] Although a single wire lumen 902 is shown in FIG. 9, other embodiments may provide multiple lumens, each containing a subset of the electrical wires used in the system.

[0085] Returning to the cross-section of FIG. 9, the catheter body 801 may further provide an internal optical lumen 903, which may extend the length of the catheter 800. The optical lumen 903 may be positioned near or in abutment with a distal plane of the circular distal portion of 800 that is in contact with the endocardial wall surface 901. One or more openings 803 (e.g., openings 803A, 803B) may be provided in the optical lumen 903 to expose the optical lumen 903 to the outside of the catheter. The openings 803 may be used to project light out of the catheter and into the endocardial wall 901, and may also be used to receive light reflected back into the catheter for measurement. The openings 803 may be holes, slots, or squibs formed in the catheter body 801. They can be open to the outside or can be covered by a suitable optically transparent coating (e.g., glass, polymer, or other ceramic material, etc.). Although Fig. 9 shows two openings 803A and 803B, any number of openings can be placed at any desired location around the circular distal section of the catheter 800 as shown in Figs. 9 and 8. In another embodiment, the distal section body 801 of the catheter 800 can be made entirely from an optically transparent material. In some embodiments, the openings 803A, 803B can ensure optical transparency between the optical lumen 903 and the endocardial wall 901 at the wavelengths used for optical analysis.

[0086] FIG. 10 illustrates the device shown in FIG. 9, but with the optical catheter 1001 inserted into the optical lumen 903 from the proximal end on the left. The optical catheter 1001 can be moved independently from the distal end of the main catheter 800 system. Movement of the optical catheter 1001 can be accomplished by a control at the proximal end of the system (not shown). The control can be part of the proximal handle assembly or can be in one of the external devices to which the catheter connects. The control can be a simple push / pull wire. The control can be a rotary knob, wheel, lever, slider, push button, or the like. The control can be geared or pinion-based to provide precision movement of the optical catheter 1001 through the optical lumen 903. The control can provide a locking function to hold the optical catheter 1001 in place relative to the optical lumen 903 and release it for movement to a new location. The control can be manual or motorized (including a stepper motor or linear displacement drive). It can provide a user interface to indicate the location of the optical catheter 1001 relative to the optical lumen 903 or other physical components of the system. The user interface can provide visual, audio, or tactile feedback to the catheter operator.

[0087] An optical opening 1003 is near the distal end of the optical catheter 1001. When the console projects optical energy 1002 through the optical catheter 1001, it may exit the catheter 1001 through the opening 1003. When the opening 1003 is aligned with one of the openings 803 in the outer catheter body 801, the optical energy 1002 may exit the catheter body 801 and enter the endocardium 901. Additionally, at least some of the optical energy 1002 may reflect back from tissue at or below the surface of the endocardium 901 and re-enter the optical catheter 1001.

[0088] The optical lumen opening 1003 can take any of the forms previously described with respect to the opening 803 in the outer catheter body 801. The form of the opening 1003 can be different than the opening 803. The optical lumen 903 and the optical catheter 1001 can be provided with features to ensure rotational alignment between the opening 1003 and the opening 803. The catheter operator can advance and retract the optical catheter 1001 along the optical lumen 903 and can stop at any location where the opening 1003 of the optical catheter aligns with the opening 803 on the outer catheter body 801. At these locations, the operator can take optical readings and evaluate tissue parameters of interest. The system can be configured with the optical catheter 1001 already partially or completely inserted into the optical lumen 903 when the catheter 800 is introduced into the target anatomy, which can be the heart. In an alternative embodiment, catheter 800 can be advanced to the target anatomy with optical lumen 903 empty, and optical catheter 1001 introduced later in the procedure.

[0089] In other embodiments, different types of catheters may be interchanged with the optical catheter 1001. The optical lumen 903 can accommodate alternative catheters that can perform different functions when aligned with the opening 803 on the catheter body 801. Examples of interchangeable alternative catheters include catheters for OCR, spectroscopy including near infrared spectroscopy, degree of polarization uniformity, or other optical measurements, electrical stimulation or ablation with PFA or radio frequency energy, electrical sensing including electrograms or impedance measurements, mechanical site marking including placement of markers such as pin clips or suture wires, other site marking including dye injection or tissue staining for fluoroscopic viewing, for ultrasound viewing, or for compatible electrophysiology navigation systems, biopsy, drug injection into tissue or elution into the blood stream, photography or videography, chemical property measurements, mechanical property measurements including durometer, localized ultrasound, laser suturing or ablation. The outer structure of catheter 800 can allow for precise placement of the catheter and precise targeting of the location in the window (e.g., opening 803) for these and other exemplary catheter types. The operator can exchange different catheter types (including variations of the same catheter type) as desired throughout the procedure.

[0090] 11 provides a cross-section of the distal end of catheter 800, looking from the proximal end toward the distal end, at a location between or outside electrodes 802 (not shown). The view is oriented such that endocardial wall 901 is on the right side of catheter 800. Within body 801 of catheter 800 are wire lumen 902, optical lumen 903, and optical catheter 1001, which are drawn to a different scale than in previous figures. Optical lumen 903 abuts a side of catheter body 801 that is configured to contact endocardial wall 901. Openings 803 and 1003 are cut into catheter body 801, optical lumen 903, and optical catheter 1001, respectively, at locations indicated by two horizontal hashed lines, allowing optical energy 1002 to exit and re-enter optical catheter 1001. The optical lumen 903 is provided with a groove 1101 to receive a tongue 1102 on the optical catheter 1001. The tongue 1102 and groove 1101 extend the length of the catheter 800 and ensure rotational alignment between the openings 803 and 1003. The optical catheter 1001 can be translated proximally or distally (into or out of the plane of the page) relative to the optical lumen 903 without misaligning the openings 803 and 1003. While tongue-and-groove alignment is shown in this embodiment, other embodiments can use different alignment means, including, but not limited to, oval, polygonal, or other interlocking cross-sectional shapes for the optical catheter 1001 and optical lumen 903, multiple polygonal tongue-and-groove shapes, a guidewire extending into the optical lumen 903 that fits into an inner smaller lumen of the optical catheter 1001.

[0091] FIG. 12 is a side cross-sectional view of the distal end of the optical catheter 1001 showing some internal structures. The catheter body 1201 can include a rotational locking feature (not shown in FIG. 12), illustrated as the tongue 1102 in FIG. 11. The body 1201 can include structures (not shown), such as metal coils, to facilitate distal and proximal movement between the openings 803 while retaining flexibility to navigate tortuous anatomy during introduction and to accommodate circular or other shapes shown in FIG. 8. Inside the body 1201, a focusing lens 1203 is rigidly fixed to the body 1201. The lens 1203 can be a microlens made of glass, fused silica, silicon dioxide, sapphire, or other materials. The fiber optic cable 1202 can be connected to the lens 1203 by adhesives, such as index-matching epoxy, laser welding, or other means. In an embodiment, the distal end of the fiber optic cable 1202 may be directly polished to act as a lens. The fiber optic cable 1202 may extend the length of the catheter 800 and terminate in an optical connector (not shown) at the proximal end of the catheter 800. The optical connector may connect to a console (not shown) and transfer optical energy between the console and the catheter. The focused optical energy 1002 may exit the lens 1203 from left to right in the figure, be turned by the angled mirror 1204, and project through the opening 1003 into the endocardium 901 (not shown). The optical energy 1002 may penetrate the tissue layers of the endocardium 901 and a portion of it may be reflected back into the optical catheter 1001 along the same path it entered. Additionally, the turning mirror 1204 may be rigidly fixed to the optical catheter body 1201, preserving optical alignment by eliminating relative motion between the lens 1203, mirror 1204, opening 1003, and rotational positioning tongue 1102 (not shown in FIG. 12).

[0092] FIG. 13 provides a side cross-sectional view to illustrate an alternative embodiment of an optical catheter 1001. In some embodiments, the mirror 1204 may not be necessary as shown in FIG. 13. Instead, a highly flexible optical fiber 1202 is used that is capable of making a 90 degree turn at its attachment point to the lens 1203, which is rigidly affixed directly to the opening 1003 by adhesive, a separate holder, a molded structure to receive the lens, or other means. Other concepts of internal arrangement of optical components within the optical

[0093] Both the external structure within the catheter 800 and the internally movable optical catheter 1001 may be provided with coatings or materials in selected locations that facilitate visualization on fluoroscopy, navigational mapping, ultrasound, computed tomography, or other imaging systems.

[0094] In an alternative embodiment, the electrodes 802 and the openings 803 may be located on a separate catheter that is attached to the side as shown in FIG. 14. In this example, the outer catheter 1401 may resemble the circular distal end of the catheter body 801 shown in FIG. 8 and may have electrodes 802 positioned at intervals thereon, each connected to an inner wire that may extend proximally through the catheter 800 as in the embodiment of FIGS. 8-12. However, in the embodiment of FIG. 14, the inner catheter 1402 may be attached laterally to the outer catheter 1401 such that the two form a concentric shape. The inner catheter 1402 may be provided with openings 803 to allow light to be transported in and out of the inner catheter 1402. The inner catheter 1402 may essentially be a hollow sheath that may receive, orient, and guide the optical catheter 1001 in the manner of the optical lumen 903 of FIG. 10. Alternatively, the inner catheter 1402 can be a slot, wire frame, track, or rail inside the outer catheter 1401 that directly receives the optical catheter 1001 and routes it around the inside of the inner catheter 1402 as the optical catheter 1001 is pushed. In these embodiments, the inner catheter 1402 would not have an outer coating, only a guide track or the like, and the outside of the catheter 1001 would be exposed to the outside. In this and other illustrations, the openings 803 are shown as discrete windows, but in other embodiments they can be slot-like windows, allowing more flexibility in viewing location. Also, the inner catheter 1402 can be made entirely of an optically clear material for maximum locational flexibility.

[0095] In another embodiment, the positions of the inner catheter 1402 and outer catheter 1401 may be reversed such that the outer catheter 1401 provides the optical aperture and the inner catheter 1402 provides the electrodes.

[0096] In another embodiment, a third catheter (not shown) similar to the inner catheter 1402 can be placed outside the outer catheter 1401. In this three catheter embodiment, the middle catheter can have an opening 803 and the outer two catheters can have electrodes 802, or vice versa. Different embodiments can be advantageous in creating larger lesions versus having a larger observation area to evaluate the lesion.

[0097] In another embodiment, both the inner catheter 1402 and the outer catheter 1401 can be provided with both electrodes 802 and openings 803 as in FIG. 8. Here, the operator can select between the two and insert the movable optical catheter 1001 through one or the other, or can insert the optical catheter 1001 into each one simultaneously to view multiple locations. Alternatively, the shaft of the catheter 800 can include a single optical lumen 903, which can be steered into one or the other catheter 1401 or 1402 at a point near the distal portion, where the catheters 1401 and 1402 can form a "Y" connection.

[0098] 15 to 20 illustrate an alternative embodiment. FIG. 15 illustrates an enlarged cross section of a simplified version of the outer catheter 1500 shown in FIGS. 8 and 9. In this version, the outer body 1501 may be provided with electrodes 1502 and openings 1503 in the same manner as described in FIGS. 8 and 9. As in the previous embodiment, the conductive electrodes 1502 may be exposed on the outside of the catheter body 1501, and it is possible to provide a connection to a wire from inside the body 1501. However, in this embodiment, the body of the outer catheter 1501 may not include a wire or an inner lumen for routing the wire.

[0099] FIG. 16 is a side view of the distal end of an inner catheter 1504 configured for linear translation within an outer catheter 1500. The catheter body 1505 is formed of a material flexible enough to navigate tortuous anatomy and stiff enough to be pushed distally and pulled proximally by a control device in the catheter 1500 handle (not shown) of the control type disclosed above. The catheter body 1505 can include a metal braid (not shown) for pushability. At least two conductive electrodes 1506 can be disposed on the outer surface of the body 1505, spaced apart at a desired distance for application of PFA energy or for electrical sensing of impedance, cardiac signals, or catheter location. The electrodes 1506 can be connected to an inner portion of the catheter body 1505 for connection to a wire and can be similar to the electrodes 802 from FIGS. 8 and 9. At least one opening 1003 is disposed between the electrodes 1506 and is similar to the opening 803 from FIGS. 8 and 9. It can be a completely open aperture or it can be covered by an optically transparent material. Optical energy 1002 can pass into and out of the opening 1003. It will be apparent to one skilled in the art that the size, number, and placement of the openings 1003 and electrodes 1506 along the body 1505 can vary in different embodiments, allowing for design tradeoffs between robustness of functionality versus complexity of assembly.

[0100] FIG. 17 illustrates a side cross-sectional view of the inner catheter 1504 showing the internal components. The body 1505 includes wire lumens 1508, which can extend partially or completely the length of the inner catheter 1504. The wire lumens 1508 include wires 1509, at least one for each electrode 1506. As in FIGS. 8 and 9, the wires can be connected to the electrodes by various means previously described, which are shown in FIG. 17 as black circles at the end of each wire 1509. The body 1505 can also include a set of optical components rigidly fixed to the body 1505. These components can include the lens 1203 and turning mirror 1204, as shown in FIG. 12. The rigidly fixed optical components can transmit optical energy 1002 between the inner catheter 1504 and the outside through the opening 1003, as previously described. The optical fiber 1202 can be connected to a lens 1203 as previously described and can guide optical energy in both directions through the length of the inner catheter 1504 .

[0101] It will be apparent to one of ordinary skill in the art that other arrangements and types of optical components are possible, including those shown in Figure 13 and elsewhere herein. Additionally, the separate wire lumen 1508 shown in Figure 17 may be partially or completely omitted, and the entire volume within the body portion 1505 may be used to contain the wire 1509 and optical fiber or fibers 1202 over some or all of the length of the inner catheter 1504.

[0102] 18A and 18B illustrate diagrams showing the translation of the inner catheter 1504 when placed in the outer catheter 1500. In FIG. 18A, the inner catheter 1504 is shown in a position where its two electrodes 1506 are not aligned with the electrodes 1502 of the outer catheter 1500, and consequently the opening 1003 of the inner catheter 1500 is also not aligned with the outer catheter opening 1503. Since there is no electrical connection between the inner and outer electrodes, no electrical functionality (stimulation or sensing) is possible. Similarly, since the inner and outer openings are not aligned, optical energy 1002 cannot be transferred between the catheter system and the endocardial tissue 901. Translating the inner catheter 1504 distally causes the inner electrode 1506 to align with the outer electrode 1502, as shown in FIG. 18B, completing the electrical circuit and optical path between the tissue 901 and the console (not shown), thereby enabling full electrical and optical functionality for the catheter system.

[0103] Alignment or misalignment of the electrodes and windows, as well as contact with the endocardial wall, can be detected by the PFA-OCR system by measuring the electrical impedance between the inner electrodes 1506 using circuitry in the console or catheter. An unaligned catheter will register a high impedance. An aligned catheter with good endocardial contact will exhibit an impedance of the endocardial wall (typically tens to hundreds of ohms). Similarly, the OCR system can be used to detect alignment between the inner opening 1003 and the outer opening 1503, since the optical energy 1002 reflected from the inner wall of the outer catheter body 1501 will typically provide a measurably different reflection than the optical energy 1002 reflected from the endocardial tissue 901.

[0104] As discussed in connection with other embodiments, a means for inserting the inner catheter 1504 into the outer catheter 1500 may be provided at the proximal end in a handle, which may provide various controls for precise translation of the inner catheter 1504 relative to the outer catheter 1500. The system may also provide a display to indicate relative catheter location, position, and alignment status. As with other embodiments, the inner catheter 1504 may be preloaded over the entire length of the outer catheter 1500. Alternatively, the inner catheter 1504 may be introduced into the outer catheter 1500 later in the procedure, after the catheter 1500 has been introduced into the target anatomy. Partial preloading is also possible.

[0105] FIG. 19 is a cross-section of a catheter system embodiment including an outer catheter 1500 and an inner catheter 1504, looking down the length of the catheter similar to FIG. 11. Here, the outer body 1505 of the inner catheter 1504 is shown in cross-section with its internal components not shown. The outer catheter 1500 body 1501 can be provided with an internal mechanical structure 1510 that provides a groove 1511 or similar guiding feature down the length of the catheter. The groove 1511 can interface with a tongue 1512 or similar feature on the inner catheter body 1505 to ensure rotational stability and ensure proper alignment between the inner catheter opening 1003 and the outer catheter opening 1503 (not shown), similar to the system described in FIG. 11. Similar to FIG. 11, the inner guide can also ensure that the inner catheter body 1505 is oriented to abut the surface of the outer catheter body 1501 on the side that will be closest to the endocardium 901, bringing the optical components (not shown) in the inner catheter 1504 as close as possible to the endocardium 901.

[0106] The cross section in Fig. 19 is taken at a point on both the inner catheter 1504 and the outer catheter 1500 where no electrodes 1506 or 1502 are provided. In contrast, Fig. 20 presents the same cross section, but at a location where both the inner catheter 1504 and the outer catheter 1500 are provided with one of their respective electrodes 1506 or 1502. The outer catheter electrode 1502 (shown in black with white dots) surrounds the outer catheter 1500 from the outside, penetrates the catheter body 1501, and may be disposed internally on the surface of the inner wall on the mechanical guiding structure 1510 or in a groove of 1510. The internal portion of the electrode 1502 may be thicker in the area near the guiding structure 1510, as shown on the left side of the figure. The electrodes 1506 of the inner catheter 1504 can surround the outer surface of the inner catheter 1504 and can penetrate into the interior of the catheter 1504 and connect to its wires (internal penetration and wires not shown). Both electrodes 1502 and 1506 can be positioned to provide good electrical contact when they are aligned, but allow full translation of the inner catheter 1500 proximally and distally through the electrodes. Those skilled in the art will recognize various means to achieve this by careful design of material selection, placement, and thickness. The walls of the outer catheter 1500 can be designed to deform slightly when the electrodes are in contact, providing elastic energy to press the metal together and ensuring low resistance contact without stressing non-contacting areas of the catheter and inhibiting further translation. A slightly tight fit between the contacting electrodes can provide tactile feedback to the catheter system operator, indicating when the electrodes are aligned.

[0107] In another embodiment, the outer catheter 1500 may not include an electrode 1502 as shown in FIG. 15. Here, the outer catheter body 1501 may be a simple tube, but provided with an aperture disposed along its length alongside the optical opening 1503. The electrode 1506 on the inner catheter 1504 (FIG. 16) may be sized to deform the flexible outer catheter 1500 when not aligned with the aperture, but when the electrode 1506 is aligned with the aperture, the electrode 1506 will protrude through the aperture a sufficient distance to ensure low ohmic contact with the endocardium 901. The inner electrode 1506 may be formed with a thicker region (or protruding cam) on the side of the inner catheter 1504 that is aligned with the aperture (to the right of 1506 in FIG. 20, the protruding cam is not shown in the figure).

[0108] In some embodiments, the openings or apertures can take the form of discrete openings, or can be elongated slots that cover more area, allowing for design tradeoffs between precise location and distance coverage.

[0109] In yet another embodiment, the outer catheter 1500 need not be a complete tube, but can be a rigid guide rail structure, either circular as in FIG. 8, or a different circular or polygonal shape formed into a plane parallel to the endocardial wall. The inner catheter 1504 can be equipped with both electrodes and optics as shown in FIG. 16, but can be provided with mechanical means for attachment to the guide rail structure. The guide rail structure allows the electrodes 1506 to contact the endocardial surface 901 and positions the opening 1003 close enough to the surface 901 to effectively probe it optically, typically at a distance of less than about 500 μm. The guide rail structure can take the form of a wire frame, with longitudinal wires connected at intervals by circular or semicircular support wires. Also, the guard rail structure can be a single rail with tongue-and-groove or similar attachment features, or it can be a complete tube with a wide slot or slots running longitudinally on the side facing the endocardium 901. In another embodiment, the guide rail structure can take the form of a single thick rigid or semi-rigid wire that provides an appropriate rounded shape. The inner catheter 1504 includes a lumen on the exterior or interior of its main shaft that can be connected to a large wire.

[0110] As discussed above, the openings 1003 and 1503 in various embodiments can be completely open apertures or can be covered by a material that is optically transparent to the wavelengths used by the system. If open apertures are used, it may be necessary to provide a means to prevent blood or other optically opaque materials from blocking the optical energy path 1002. Irrigation of the catheter system with a biocompatible optically transparent liquid (such as, for example, saline solution) can be used for thermal control and to prevent tissue buildup at the tip of the RF ablation system. The catheter systems disclosed above can include irrigation ports at their proximal ends, allowing forced irrigation of the openings 1003 or 1503 to keep them optically clear or to prevent backflow of blood into the catheter system. The irrigation fluid medium can be a medical grade saline solution or any liquid that is biocompatible and optically transparent. It may be desirable to formulate the solution with index-matching liquids or other materials to improve optical transmission or fluid properties (such as, for example, viscosity or lubricity). Instead of a liquid, a viscous gel can be added to the space behind the opening and allowed to remain there to keep the optical path clear.

[0111] In another embodiment, the moving catheter is coupled to a relatively stationary catheter, as in the previous embodiment, but in this case the relative motion can be rotational rather than translational. FIG. 21 illustrates a cross-sectional view of the distal portion of a PFA-OCR catheter 2100, with the longitudinal axis of the catheter running from left to right across the page. This can be a two-catheter system, where an inner optical catheter 2102 can reside within an outer catheter 2101. An optical aperture 2103 can be disposed along the outer catheter 2101 along the side that contacts the endocardium (not shown, bottom of figure), as in the previously described embodiment. Inside the inner optical catheter 2102 can be multiple optical tap assemblies 2104, with optical fibers 2105 running lengthwise through the optical tap assemblies 2104. Throughout the figures, optical energy is symbolized by a solid black arrow in both directions. Each optical tap assembly 2104 may be configured to tap a portion of the optical energy flowing therein through the fiber 2105 from a laser source in the console (not shown) and transmit the tapped portion to a micro-lens 1203 for focusing and transmission through the inner catheter 2101 opening 2106. The untapped portion of the incoming optical energy may continue through the fiber to the next optical assembly 2104. For example, optical energy from the console laser source may travel from left to right (proximal to distal) along the fiber 2105. As the input optical energy 2107B enters the optical assembly 2104B, it may encounter a semi-reflective turning mirror 1204B. This mirror may be fabricated with a partially reflective coating, causing a portion of the input energy 2108B to be reflected at a predetermined angle (90 degrees in the illustrative illustration), and the remaining portion of the input energy 2109B may be transmitted through the mirror 1204B and further distally through the fiber 2105.The tapped optical energy 2108B can be focused by lens 1203B and projected through the inner catheter opening 2106B. The inner catheter 2102 can be configured to rotate about its longitudinal axis (from left to right in the figure), while the outer catheter 2102 can be configured to remain stationary. In the illustrative illustration, the inner catheter 2102 is rotated relative to the outer catheter 2101 so that the openings 2106B and 2103B align, allowing the optical energy 2108B to leave the catheter and enter the endocardium (not shown). The projected light 2108B then reflects off the endocardium or other tissue and travels back along the same path it entered, coupled back into the fiber 2105 and carried to the console for signal acquisition and measurement.

[0112] The optical assemblies 2104 are oriented around the longitudinal axis of the inner catheter 2102 at their own unique angle as shown in Figures 21 and 22. In the figures, the three optical assemblies 2104 are oriented at 90 degrees to each other. In Figure 21, optical assembly 2104A (including aperture 2106A) is shown with its lens and tapped optical energy facing out of the page, assembly 2104B including aperture 2106B is oriented to send tapped optical energy 2108B downward, and optical assembly 2104C including aperture 2106C is oriented to send its tapped optical energy upward. All items in the inner catheter 2102 can be fixed relative to the catheter and can rotate together when the operator rotates the inner catheter 2102 from a control at the proximal end of the catheter. The optical assembly 2104 and inner catheter opening 2106 can be oriented such that at any given time, at most only one optical assembly opening 2106 is aligned with the outer catheter opening 2103. All optical assemblies 2104 can be permanently fixed to the fiber 2105 so that they can all pass optical energy 2108 simultaneously when energy is applied by the console. The optical assemblies 2104 (whose openings 2106 are not aligned with the outer window 2103) can project optical energy 2108 into the inner wall of the outer catheter 2101. The inner wall of the outer catheter 2101 can be made of or coated with a non-reflective material that absorbs light at the wavelengths used by the system to ensure that little or no optical energy is reflected back into the fiber 2105.

[0113] Figure 22 provides a cross-sectional view of a two catheter system 2100 looking towards the distal end of the catheter section shown in Figure 21. Optical assemblies 2104 are shown with 2104A shaded darkest, indicating it is most proximal to the viewer, 2104B shaded lighter, indicating it is more distal than 2104A, and 2104C shaded lightest of all, indicating it is most distal. This view clarifies the concept of rotational selection of the active optical measurement aperture by the user.

[0114] Although partially reflective turning mirrors are shown in Figures 21 and 22, tapping of optical energy from fiber 2105 and recombining the returning energy back into fiber 2105 can be accomplished by other means. These include optical splitter / coupler devices, which can be designed to couple or split a desired portion of the total optical energy to / from the tap port. They also include passive devices (such as gratings or prisms) capable of redirecting light at different wavelengths into different spatial directions, which can be used in combination with multi-wavelength or broadband light.

[0115] Obviously, additional optical assemblies 2104 can be disposed at different angles to allow for more viewports into the catheter system 2100 as desired. Although Figs. 21 and 22 do not show electrodes, it will become apparent that electrodes and wires can be added in a similar or similar manner to those in the previously disclosed embodiments. For example, the cross section of Fig. 22 can be modified to make the outer catheter 2101 larger in diameter to accommodate the electrode wires in the previous embodiments, either in a dedicated lumen or in the main lumen of 2101. Additionally, a rotary electrode-selective switch similar to the optical one shown in Figs. 21 and 22 can be easily visualized, with a cam or other protruding inner electrode disposed in the inner catheter 2102 that protrudes through an opening or otherwise contacts a stationary outer electrode only when a particular rotation angle is selected that causes the inner and outer electrodes to align. Rotationally aligning electrodes and optical assemblies can be combined together in the catheter 2101 such that both, as well as their previously described translational analogs, can be simultaneously engaged when desired. Any combination of multi-fiber and single fiber or wire combinations can be designed to meet particular user needs and manufacturing constraints.

[0116] The described rotationally selectable two-catheter system may be locked so that the inner catheter 2102 cannot translate within the outer catheter 2101. The rotatable inner catheter 2102 may be permanently fixed to the distal end of 2101 by any of a number of mechanical means. However, it will become apparent from this disclosure that combinatorial embodiments of the system that allow both translational and rotational movement of one catheter relative to the other are possible and may be used for a particular design.

[0117] In other embodiments, the distal end of the PFA-OCR catheter can have multiple separate branches that do not form a continuous loop. The general principles of the present disclosure are compatible with such multi-loop architectures. It is possible to simply provide separate parallel systems for each branch in the same overall catheter system. Alternatively, parallel branches can be created in stationary parts of the system, corresponding for example to the fixed outer catheter body 800 in FIG. 9 or 1500 in FIG. 15. The parallel branches can come together at an intersection just proximal to the most proximal opening or electrode. A single movable inner catheter 1001 in FIG. 10 or 1504 in FIG. 16 can then be inserted up to the point of intersection. Mechanical guide features can facilitate steering the movable inner catheter to the desired branch.

[0118] In other embodiments, the PFA-OCR catheter system of the present disclosure may be used with a distal end in the form of a three-dimensional basket, possibly shaped by a balloon device. In some embodiments, the basket may use loops or branches, as described above.

[0119] The exemplary embodiment shown in the figures shows a single optical assembly (fiber, lens, etc.) in a translatable inner catheter. In other embodiments, multiple fiber-lens assemblies can comprise the optical portion of the system and can be stationarily fixed to the body of either a movable catheter or a stationary catheter. Multiple instances of the optical assembly of the type illustrated in FIG. 12 or FIG. 13 can be disposed in a single catheter. In one embodiment, multiple fibers can extend the length of the catheter to at least one proximal optical connector. In another embodiment, a single optical fiber extends through most of the catheter length, but at a location near the distal end, the single fiber fans out into multiple fibers via an optical multiplexer, with each downstream fiber connected to at least one separate optical channel. Optical multiplexing / demultiplexing can be accomplished by an arrangement of many micro-optical components, including (i) wavelength division multiplexing using diffraction gratings (prisms for spatially redirecting light), (ii) beam steering using movable micromirrors, (iii) polarization division multiplexing using polarizing filters, (iv) tunable wavelength filters (including acousto-optic tunable filters), and (v) liquid crystal switch devices. In some embodiments, optical multiplexing and switching can be performed by a single multiplexing device proximate the optical aperture 1003, 1503 that fans out from one optical fiber to multiple fibers. Other embodiments can take the form of a single fiber tapped at each desired optical sensing location. The tapped optical energy 1002 can be routed through an optical switch to a short fiber / lens assembly. The tap can take the form of an optical coupler / splitter or a partially reflective mirror arrangement. The individual optical pass / block switches can be implemented as wavelength filters, polarizing filters, liquid crystal switches, acousto-optic switches, or other devices.The electronics control lines for embodiments using such switches would be routed back to an electrical connector on the handle.

[0120] As the optical energy 1002 may be multiplexed to allow a few fibers to pass through most of the length of the catheter, the electrical energy may be multiplexed to reduce the number of long wires required to traverse the catheter. In such an embodiment, the electronic multiplexer may be provided at a point much more distal from the catheter proximal end, but proximal to the most proximal electronic components (electrodes 802, 1502, 1506 or control electronics for the optical multiplexer). Switching control may be augmented by any of a myriad of digital control methods and may include integrated circuits. The physical switches may be implemented as micromechanical relays or solid state switches. Electrical switches may also be placed locally near each electrode. In one embodiment, a single wire may contact multiple electrodes, each electrode having its own localized switch and control electronics, and the control electronics only opens its switch when it detects a unique control signal on the single wire that is also used to carry the stimulation power or signal. In this embodiment, the unique control signal may be a bit sequence or a unique frequency.

[0121] The electrodes can serve the functions of stimulation, measurement, or monitoring, as previously described. The electrodes can be configured to serve multiple functions or can be specialized for a single function. In one embodiment, different electrodes are configured to simultaneously stimulate and measure electrogram functionality. The electrodes can also monitor the patient's electrocardiogram (ECG) function and inhibit PFA stimulation during portions of the ECG cycle during which external electrical stimulation may cause fibrillation or other undesired responses. An example of such a PFA stimulation inhibition system can include using one or more electrodes to monitor the ECG, processing the signal to determine when the "T" portion of the ECG cycle occurs, and inhibiting stimulation during the "T" portion of the cycle. The system can delay application of stimulation, for example, after the "T" wave has ended, until the next safe portion of the ECG cycle occurs. Signal processing can occur in the console or can be performed by electronics in the catheter. It may involve measuring a well-defined event in the cardiac cycle (such as the descent of the "R" wave) and then inhibiting stimulation for a physiologically reasonable period after the "R" wave. The length of the inhibition period may be the same for every cardiac cycle, or it may vary automatically based on recent measurements of heart rate or other parameters.

[0122] In other embodiments of the present disclosure, the catheter system may be configured to perform RF ablation (RFA) as well as PFA. The system may have electrodes uniquely placed for RFA functionality and other electrodes for PFA functionality. Alternatively, the same electrodes may be used for both PFA and RFA at discrete times by using circuitry in the console to switch the different electrical stimuli (PFA or RFA) into the desired electrodes. When used in RFA mode, a dispersive pad may be placed on the patient's back to disperse the RF current and provide a return path. In this case, only one of the electrodes of the present disclosure may be excited by RF energy at a time. If desired, RFA may be applied across two of the system's electrodes. The user may be provided with controls on the catheter or at the console to toggle the system between PFA and RFA modes. The optical system may measure and display the same optical parameters for both modes, or may be configured to measure and display unique parameters for each mode. Irrigation holes and channels may be provided on or near the electrodes intended for RFA.

[0123] In other embodiments, the present disclosure may be modified to achieve cryogenic ablation. In one embodiment, the catheter may have a balloon affixed to its distal end that is configured to be filled with a cryogenic liquid (such as, for example, liquid nitrogen) provided by a console or other external device. The inner and outer catheters of the present disclosure may be configured to surround the balloon in a continuous serial pattern or may be configured as multiple parallel distal sections that may be selected as previously described.

[0124] In RF, cryogenic, or PFA embodiments, the present disclosure features flexibility in placement of optical observation locations relative to the ablation stimulus (electrical or cryogenic) locations, allowing the designer to select the observation location around the created lesion that will be of most interest when assessing lesion quality.

[0125] In some embodiments, a means for adjusting the shape of the distal portion of the catheter of the present disclosure may be provided. This may include a pull wire or push rod controlled by the user. The adjustment means may be used to increase or decrease the diameter of the circle or the size of the polygonal shape at the distal end of the catheter system.

[0126] Although the cross sections of the present disclosure shown in Figures 11, 19, 20, and 22 show circular cross sections, other geometries for the distal section may be advantageous. A semicircular shape with the flat side facing the endocardium 901 has the advantage of covering more area of ​​the endocardial wall with each electrode, which may provide better electrical contact. It may also reduce the distance between the optical opening and the endocardium, allowing deeper penetration of the optical energy into the endocardial tissue.

[0127] In another embodiment, the outer catheter in the various disclosed embodiments is rotatable by the user to allow for better positioning of the outer catheter openings or electrodes to interface with the endocardium.

[0128] In other embodiments, various features can be added to the present disclosure to improve contact between the outer catheter openings and electrodes and the endocardial wall, including balloons or other mechanical structures to press the catheter distal section against the wall, slightly roughened or abrasive surfaces to reduce slippage.

[0129] The illustrations of this disclosure use exemplary embodiments from cardiac pulsed fields and RF ablation, specifically ablation of endocardial tissue near the ostia of pulmonary veins. However, the principles of this disclosure can be applied to other anatomical structures where tissue ablation may have clinical value. These include, but are not limited to, cancerous or precancerous tumors, skin cells, neural tissue for procedures such as renal denervation, other neural cells, brain cells, or mucus or other congestive material that may cause, for example, pulmonary edema.

[0130] Additional Exemplary Embodiments EXEMPLARY EMBODIMENT SET #1 Embodiment 1: A system for ablating tissue of a cardiac wall, the system comprising: a catheter configured to be placed within an outer sheath, a distal end of the catheter adapted to assume a straight configuration compatible with vascular delivery, the distal end adopting a circular shape when pushed through the sheath, the circular shape lying in a plane parallel to the heart wall and configured to contact the heart wall; a plurality of electrodes disposed on the distal end at predetermined distances from each other, the electrodes being connected by wires to an external electrical energy generating device via an electrical connector on the proximal end of the catheter, the electrodes being configured to deliver electrical energy to the heart wall when excited by the electrical energy generating device; at least one optical port including an optical component connected by an optical fiber to an external optical energy generating device via an optical connector on a proximal end of the catheter, the optical component configured to project optical energy into the heart wall when excited by the optical energy generating device, configured to receive optical energy reflected back from the heart wall, and configured to transfer the reflected energy through the fiber and the optical connector to an external optical sensing device; Including, The system, wherein the at least one optical port is positioned on the distal end of the catheter at a predetermined location relative to the electrode, the location being selected for optimal measurement of optical parameter changes caused by tissue ablation due to the excitation of the electrode.

[0131] Embodiment 2: The system of embodiment 1, wherein the sides of the catheter configured to contact the heart wall are flattened to generate a semicircular cross-section of the catheter, the flattened sides maximizing the contact area between the sides and the heart wall.

[0132] Embodiment 3: The system of embodiment 1, wherein the circular shape is an oval shape, a polygonal shape, or a combination of an oval shape and a polygonal shape.

[0133] Embodiment 4: The system of embodiment 1, wherein at least two electrodes of the plurality of electrodes are connected to dedicated wires, the plurality of dedicated wires are connected to a multiplexer positioned proximal to the electrodes, the multiplexer configured to selectively switch between the dedicated electrode wires and at least one proximal wire, the proximal wire extending from the multiplexer to a connector on the proximal end of the catheter.

[0134] Embodiment 5: The system of embodiment 1, wherein a subset of the plurality of electrodes are wired together to form a single electrical node.

[0135] Embodiment 6: The system of embodiment 1, wherein the system includes a plurality of the optical ports and further includes an optical multiplexer positioned proximal to the optical ports, the optical multiplexer configured to selectively switch between a plurality of optical fibers and at least one proximal fiber, each of the fibers dedicated to one of the optical ports, and the proximal fiber extending from the multiplexer to a connector on the proximal end of the catheter.

[0136] Embodiment 7: The system of embodiment 1, wherein the optical component is selected from a focusing lens, a turning mirror, a diffraction grating, a GRIN lens, an optical tap, an optical coupler, and an optical polarizer.

[0137] Embodiment 8: The system of embodiment 1, wherein the electrical energy delivered to the cardiac wall by the plurality of electrodes is configured to ablate tissue of the cardiac wall by at least one process selected from radio frequency ablation, thermal ablation, pulsed field ablation, or irreversible electroporation.

[0138] Embodiment 9: The system of embodiment 8, wherein a system operator is able to select the type of electrical energy delivered by a controller on the external electrical energy device.

[0139] Embodiment 10: The system of embodiment 1, wherein the external optical energy generation device, the at least one optical port, and the external optical sensing device are configured to perform the optical measurement of optical parameter changes by at least one process selected from optical coherence tomography, optical coherence reflectometry, low coherence interferometry, polarization uniformity degree measurement, polarization sensitive optical coherence tomography, reflectance intensity, spectroscopy, Raman spectroscopy, and near infrared spectroscopy.

[0140] Embodiment 11: The system of embodiment 10, wherein the optical measurements can be processed and displayed by an external device and can indicate at least one of contact stability between the optical port and the heart wall, tissue viability, tissue type, tissue depth, and tissue composition.

[0141] Embodiment 12: The system of embodiment 11, wherein the processed and displayed optical measurements provide data relating to a depth of at least 1 millimeter into the tissue being measured.

[0142]

[0046] Embodiment 13: The system of embodiment 11, wherein the external device includes an algorithm for calculating and displaying an estimated depth of the lesion.

[0143]

[0023] Embodiment 14: The system of embodiment 10, wherein the system measures birefringence of tissue of the heart wall.

[0144] Embodiment 15: The system of embodiment 1, wherein the location selected for optimal measurement of optical parameter change is at the midpoint between two electrodes configured to serve as a positive node and a negative node for pulsed field ablation stimulation.

[0145] Embodiment 16: The system of embodiment 1, wherein at least one of the electrodes is configured to perform a plurality of functions when connected to at least one external device via the electrical connector on the proximal end of the catheter, the functions being selected from electrical stimulation, electrogram measurement, electrocardiogram measurement, and tissue impedance measurement.

[0146] Embodiment 17: The system of embodiment 1, wherein the measurement of the optical parameter is performed before, during, or after the delivery of the electrical energy to assess the effectiveness of the delivery.

[0147] Embodiment 18: The system of embodiment 1, wherein the distal end includes a plurality of distal ends, each of which is provided with its own electrode and optical port, and is configured in parallel shapes including a plurality of lines, circular shapes, or polygons.

[0148] Embodiment 19: The system of embodiment 18, wherein the plurality of distal ends are configured in a three-dimensional spheroid shape.

[0149] EXEMPLARY EMBODIMENT SET #2 Embodiment 20: A system for ablating tissue of a cardiac wall, the system comprising: a first catheter configured to be placed within an outer sheath, a distal end of the first catheter configured to assume a straight configuration compatible with vascular delivery, the distal end of the first catheter configured to assume a circular shape when pushed through the sheath, the circular shape lying in a plane parallel to the heart wall and configured to contact the heart wall; a second catheter configured to longitudinally connect to the first catheter and configured to translate distally or proximally along the first catheter; Including, the second catheter further comprises a plurality of electrodes disposed on a distal end of the second catheter at a predetermined distance from each other, the electrodes being connected by wires to an external electrical energy generating device via an electrical connector on a proximal end of the second catheter, the electrodes being configured to deliver electrical energy to the heart wall when excited by the electrical energy generating device; the second catheter further comprises at least one optical port, the port comprising an optical component connected by an optical fiber to an external optical energy generating device via an optical connector on a proximal end of the second catheter, the optical component configured to project optical energy into the heart wall when excited by the optical energy generating device, configured to receive back optical energy reflected from the heart wall, and configured to transfer the reflected energy through the fiber and the optical connector to an external optical sensing device; The system, wherein the at least one optical port is positioned on the distal end of the second catheter at a predetermined location relative to the electrode, the location being selected for optimal measurement of optical parameter changes caused by tissue ablation due to the excitation of the electrode.

[0150] Embodiment 21: The system of embodiment 20, wherein the first catheter is configured to provide a fixed, planar pathway relative to the heart wall and configured to remain in position while the second catheter is translated distally or proximally about the pathway by an operator.

[0151] Embodiment 22: The system of embodiment 20, wherein the second catheter is connected to the first catheter by a lumen disposed on the second catheter, and the first catheter is configured to fit within the lumen.

[0152] Embodiment 23: The system of embodiment 20, wherein the second catheter is connected to the first catheter by a lumen disposed on the first catheter, and the second catheter is configured to fit within the lumen.

[0153] Embodiment 24: The system of embodiment 20, wherein the first catheter further comprises at least one of the electrodes connected to the external electrical device or at least one of the optical ports connected to the external optical device.

[0154] Embodiment 25: The system of embodiment 20, wherein at least a portion of a side of the first catheter facing the heart wall is provided with at least one optically transparent opening, and the at least one optical port of the second catheter is configured to align with said opening when translated to its location.

[0155] Embodiment 26: The system of embodiment 20, wherein the second catheter can be rotated about its longitudinal axis relative to the first catheter.

[0156] Embodiment 27: The system of embodiment 20, wherein the second catheter is rotationally aligned within the first catheter to ensure that the optical port is directed toward the heart wall, and further wherein the second catheter includes means for inhibiting rotation about its longitudinal axis relative to the first catheter.

[0157] Embodiment 28: The system of embodiment 20, wherein the first and second catheters are each provided with at least one electrode, a pair of electrodes that are in electrical contact with each other when the second catheter is translated to a specific location, the electrical contact establishing a connection from an external electrical device to one of the pair of electrodes in contact with the heart wall.

[0158] Embodiment 29: The system of embodiment 20, wherein the longitudinal axes of the first and second catheters are concentric.

[0159] Embodiment 30: The system of embodiment 20, wherein the longitudinal axes of the first and second catheters are separate and parallel.

[0160] Embodiment 31: The system of embodiment 20, wherein the side of the second catheter configured to contact the heart wall is flattened to generate a semicircular cross-section of the catheter, the flattened side being configured to maximize the contact area between the side and the heart wall.

[0161] Embodiment 32: The system of embodiment 20, wherein the circular shape is an oval shape, a polygonal shape, or a combination of an oval shape and a polygonal shape.

[0162] Embodiment 33: The system of embodiment 20, wherein the optical component is selected from a focusing lens, a turning mirror, a diffraction grating, a GRIN lens, an optical tap, an optical coupler, and an optical polarizer.

[0163] Embodiment 34: The system of embodiment 20, wherein the electrical energy delivered to the cardiac wall by the plurality of electrodes is configured to ablate tissue of the cardiac wall by at least one process selected from radio frequency ablation, thermal ablation, pulsed field ablation, or irreversible electroporation.

[0164] Embodiment 35: The system of embodiment 34, wherein a system operator is able to select the type of electrical energy delivered by a control on the external electrical energy device.

[0165] Embodiment 36: The system of embodiment 20, wherein the external optical energy generating device, the at least one optical port, and the external optical sensing device are configured to perform the optical measurement of optical parameter changes by at least one process selected from optical coherence tomography, optical coherence reflectometry, low coherence interferometry, polarization uniformity degree measurement, polarization sensitive optical coherence tomography, reflectance intensity, spectroscopy, Raman spectroscopy, and near infrared spectroscopy.

[0166] Embodiment 37: The system of embodiment 36, wherein the optical measurements can be processed and displayed by an external device and can indicate at least one of contact stability between the optical port and the heart wall, tissue viability, tissue type, tissue depth, and tissue composition.

[0167] Embodiment 38: The system of embodiment 37, wherein the processed and displayed optical measurements provide data relating to a depth of at least 1 millimeter into the tissue being measured.

[0168]

[0081] Embodiment 39: The system of embodiment 37, wherein the external device includes an algorithm for calculating and displaying an estimated depth of the lesion.

[0169]

[0046] Embodiment 40: The system of embodiment 36, wherein the system measures birefringence of tissue of the heart wall.

[0170] Embodiment 41: The system described in embodiment 20, wherein the location selected for optimal measurement of optical parameter change is at the midpoint between two electrodes configured to serve as a positive node and a negative node for pulsed field ablation stimulation.

[0171] Embodiment 42: The system of embodiment 20, wherein at least one of the electrodes is configured to perform a plurality of functions when connected to at least one external device via the electrical connector on the proximal end of the catheter, the functions being selected from electrical stimulation, electrogram measurement, electrocardiogram measurement, and tissue impedance measurement.

[0172] Embodiment 43: The system of embodiment 20, wherein the measurement of the optical parameter is performed before, during, or after the delivery of the electrical energy to assess the effectiveness of the delivery.

[0173] Embodiment 44: The system described in embodiment 20, wherein the distal end includes a plurality of distal ends, each of which is provided with its own electrode and optical port, and is configured in parallel shapes including a plurality of lines, circular shapes, or polygons.

[0174] Embodiment 45: The system described in embodiment 44, wherein the multiple distal ends are configured in a three-dimensional spheroid shape.

[0175] Embodiment 46: The system of embodiment 44, wherein the second catheter is steerable to select the distal end into which it will translate.

[0176] Embodiment 47: The system of embodiment 20, wherein the second catheter is translated completely distally relative to the first catheter.

[0177] Embodiment 48: The system of embodiment 20, wherein the first catheter is inserted into the outer sheath during the vascular delivery without the second catheter, and the second catheter is translated into a distal portion of the first catheter after the first catheter is pushed through the sheath.

[0178] Embodiment 49: The system of embodiment 20, wherein the second catheter is fixed to prevent longitudinal translation relative to the first catheter.

[0179] Embodiment 50: The system of embodiment 49, wherein the second catheter is configured to be selectively rotated relative to the first catheter, and further wherein the optical ports are disposed around the circumference of the second catheter such that only one port faces directly toward the heart wall over a given angle of rotation.

[0180] Embodiment 51: The system of embodiment 20, further comprising a user control configured to facilitate precise movement of the second catheter relative to the first catheter.

[0181] Embodiment 52: The system described in embodiment 51, wherein the user controls are located on one of a catheter handle of the system or an external device connected to the catheter.

[0182] Embodiment 53: The system of embodiment 51, wherein the user controls include at least one of a motor, a stepper motor, a gearing system, a rotary knob, a slider switch, a computer screen and input device, and a display indicating a precise location.

[0183] EXEMPLARY EMBODIMENT SET #3 Embodiment 54: A method for ablating cardiac tissue, the method comprising: inserting a sheath containing a first catheter device into a heart chamber; pushing the first catheter device through the sheath, the first catheter configured to assume a planar shape, the plane of the shape being oriented parallel to a heart chamber wall; translating a second catheter longitudinally along the first catheter, the second catheter configured to follow a path defined by the shape of the first catheter, the second catheter further comprising an electrode configured to sense an electrical parameter and deliver electrical energy, the second catheter further comprising an optical port configured to deliver optical energy to the heart wall and to transfer reflected optical energy back to an externally connected optical measurement device; pausing translation of the second catheter at a desired location about the path of the planar shape and delivering electrical energy to selectively ablate cardiac wall tissue; applying optical energy, measuring reflected energy, and evaluating optical parameters indicative of contact stability, tissue viability, and lesion size and depth; While fixing the position of the first catheter, repeating the steps of distal or proximal translation of the second catheter, applying electrical stimulation and, if necessary, taking optical measurements to ensure that the continuous lesion is in the desired location. removing the catheter system. A method comprising:

[0184] Embodiment 55: The method of embodiment 54, wherein the catheter system includes any of the catheter systems from embodiments 20 to 55.

[0185] Exemplary Computing Embodiments 23 is a block diagram of exemplary components of a computer system 2300. One or more computer systems 2300 may be used to implement, for example, any of the embodiments discussed herein, as well as combinations and subcombinations thereof. In some embodiments, one or more computer systems 2300 may be used to implement the methods, computing, and processing devices as described herein. The computer system 2300 may include one or more processors (also referred to as central processing units or CPUs), such as, for example, processor 2304. The processor 2304 may be connected to a communication infrastructure or bus 2306.

[0186] The computer system 2300 may also include a user input / output interface 2302 (e.g., a monitor, keyboard, pointing device, etc.), which may communicate with a communications infrastructure 2306 through a user input / output interface 2303.

[0187] One or more of the processors 2304 may be a graphics processing unit (GPU). In one embodiment, a GPU may be a processor that is a specialized electronic circuit designed to process mathematically intensive applications. GPUs may have a parallel structure that is efficient for parallel processing of large blocks of data (e.g., mathematically intensive data common to computer graphics applications, images, video, etc.).

[0188] The computer system 2300 may also include a main or primary memory 2308 (e.g., random access memory (RAM), etc.). The main memory 2308 may include one or more levels of cache. The main memory 2308 may have control logic (i.e., computer software) and / or data stored therein. In some embodiments, the main memory 2308 may include optical logic configured to perform processing and analysis of optical measurements obtained from the tissue by the catheter and to determine lesion predictions.

[0189] The computer system 2300 may also include one or more secondary storage devices or memory 2310. The secondary memory 2310 may include, for example, a hard disk drive 2312 and / or a removable storage drive 2314.

[0190] The removable storage drive 2314 can interact with a removable storage unit 2318. The removable storage unit 2318 can include a computer usable or readable storage device having computer software (control logic) and / or data stored therein. The removable storage unit 2318 can be a program cartridge and cartridge interface (such as those found in video game devices), a removable memory chip (such as an EPROM or PROM) and associated socket, a memory stick and USB port, a memory card and associated memory card slot, and / or any other removable storage unit and associated interface. The removable storage drive 2314 can read from and / or write to the removable storage unit 2318.

[0191] The secondary memory 2310 may include other means, devices, components, conveniences, or other approaches for allowing computer programs and / or other instructions and / or data to be accessed by the computer system 2300. Such means, devices, components, conveniences, or other approaches may include, for example, removable storage units 2322 and interfaces 2320. Examples of removable storage units 2322 and interfaces 2320 may include program cartridges and cartridge interfaces (such as those found in video game devices), removable memory chips (such as, for example, EPROMs or PROMs) and associated sockets, memory sticks and USB ports, memory cards and associated memory card slots, and / or any other removable storage units and associated interfaces.

[0192] The computer system 2300 may further include a communication or network interface 2324. The communication interface 2324 may enable the computer system 2300 to communicate and interact with any combination of external devices, external networks, external entities, etc. (individually and collectively (referenced by reference numeral 2328)). For example, the communication interface 2324 may enable the computer system 2300 to communicate with external or remote devices 2328 via a communication path 2326, which may be wired and / or wireless (or a combination thereof), which may include any combination of a LAN, a WAN, the Internet, etc. Control logic and / or data may be transmitted to and from the computer system 2300 via the communication path 2326. In some embodiments, the computer system 2300 may be coupled to a catheter via connectors and optical and electrical connections (including optical fibers and electrical wires, pins, and / or components) in the communication interface 2324.

[0193] Additionally, computer system 2300 may be a personal digital assistant (PDA), a desktop workstation, a laptop or notebook computer, a netbook, a tablet, a smartphone, a smartwatch or other wearable, a consumer electronics device, part of the Internet of Things, and / or an embedded system, or any combination thereof, to name a few non-limiting examples.

[0194] Computer system 2300 can be a client or a server and can access or host any application and / or data through any delivery paradigm, including, but not limited to, remote or distributed cloud computing solutions, local or on-premise software ("on-premise" cloud-based solutions), "as-a-service" models (e.g., Content as a Service (CaaS), Digital Content as a Service (DCaaS), Software as a Service (SaaS), Managed Software as a Service (MSaaS), Platform as a Service (PaaS), Desktop as a Service (DaaS), Framework as a Service (FaaS), Backend as a Service (BaaS), Mobile Backend as a Service (MBaaS), Infrastructure as a Service (IaaS), etc.), and / or hybrid models including any combination of the foregoing examples or other service or delivery paradigms.

[0195] Any applicable data structures, file formats, and schemes in computer system 2300 may be derived from standards, including but not limited to JavaScript Object Notation (JSON), Extensible Markup Language (XML), Yet Another Markup Language (YAML), Extensible Hypertext Markup Language (XHTML), Wireless Markup Language (WML), MessagePack, XML User Interface Language (XUL), or any other functionally similar representations, alone or in combination. Alternatively, proprietary data structures, formats, or schemes may be used, either exclusively or in combination with known or open standards.

[0196] In some embodiments, a tangible, non-transitory apparatus or article of manufacture including a tangible, non-transitory computer usable or readable medium having control logic (software) stored thereon may also be referred to herein as a computer program product or program storage device. This includes, but is not limited to, computer system 2300, main memory 2308, secondary memory 2310, and removable storage units 2318 and 2322, as well as tangible articles of manufacture embodying any combination of the foregoing. Such control logic, when executed by one or more data processing devices (such as, for example, computer system 2300), can cause such data processing devices to operate as described herein.

[0197] conclusion It will be apparent to one of ordinary skill in the art that the clinical ablation procedure described above need not include all of the steps as described, and such steps need not occur in the exact order that they have been presented.

[0198] It should be appreciated that the Detailed Description section (and not the Summary and Abstract sections) are intended to be used to interpret the claims. The Summary and Abstract sections may describe one or more (but not all) example embodiments of the present disclosure as contemplated by the inventors, and thus are not intended to limit the scope of the disclosure and the appended claims in any way.

[0199] The embodiments of the present disclosure have been described above with the aid of functional building blocks illustrating the implementation of certain functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of description. Alternative boundaries may be defined so long as the certain functions and relationships thereof are appropriately implemented.

[0200] The foregoing description of the specific embodiments will fully and completely reveal the general nature of the present disclosure, so that others, by applying knowledge within the skill of the art, can easily modify and / or adapt such specific embodiments for various applications without undue experimentation and without departing from the general concept of the present disclosure. Therefore, such adaptations and modifications are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It should be understood that the phraseology or terminology in this specification is for the purpose of description and not of limitation, and that the terminology or terminology in this specification is as it should be interpreted by those skilled in the art in light of the teaching and guidance.

[0201] The breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.

[0202] Moreover, the following aspects are explicitly disclosed:

[0203] 1. A system comprising: A catheter comprising: Proximal section, Distal section, a shaft coupled between a proximal section and a distal section; and a catheter including an optical circuit configured to at least partially transport light from the proximal section to the distal section and vice versa; a pulsed field ablation energy source coupled to the catheter, the pulsed field ablation energy source configured to deliver a pulsed electrical signal to the tissue sample; Processing device and The processing device includes: configured to analyze one or more optical signals received from the optical circuit to determine a change in polarization or phase delay of light reflected or scattered by the tissue sample; The system is configured to determine a change in birefringence of the tissue sample based on the change in polarization or phase retardation.

[0204] 2. The system of aspect 1, wherein the optical circuit is configured to at least partially transport light from the proximal section to the distal section and vice versa, at least partially using a polarization-maintaining transmission medium in the shaft.

[0205] 3. The system of aspect 1 or aspect 2, wherein the pulsed electrical signal delivered by the pulsed field ablation energy source is monophasic or biphasic.

[0206] 4. A system described in any one of aspects 1 to 3, wherein a change in the polarization or phase delay of light reflected or scattered by the tissue sample is in response to a pulsed electrical signal transmitted to the tissue sample.

[0207] 5. The system of any one of aspects 1 to 4, wherein the one or more optical signals include an optical coherence tomography (OCT) signal or an optical coherence reflectometry (OCR) signal acquired by the tissue sample.

[0208] 6. A system described in any one of aspects 1 to 5, wherein the optical circuit is configured to transmit light from the distal section to the tissue sample.

[0209] 7. A system described in any one of aspects 1 to 6, wherein the distal section of the catheter includes a plurality of optical ports configured to collect light reflected or scattered from the tissue sample.

[0210] 8. A system described in any one of aspects 1 to 7, wherein characteristics of the pulsed electrical signal are selected by a user of the catheter, the characteristics including frequency, amplitude, and duration of the pulsed electrical signal.

[0211] 9. A method for performing an ablation in a patient, the method comprising: inserting a catheter into the patient's vascular system; moving a distal end of the catheter to an ablation site within the patient's vasculature; establishing tissue contact at the distal end of the catheter through optical means using light delivered through the distal end of the catheter to the ablation site; delivering energy from an energy source coupled to the catheter out of a distal end of the catheter and into the tissue; optically interrogating the ablation tissue site to determine a change in polarization or phase delay of light delivered through the catheter to the ablation tissue site; removing the catheter from the vasculature; A method comprising:

[0212] 10. The method of embodiment 9, wherein the energy comprises a pulse train, the energy source comprises a pulsed field ablation energy source, the pulse train comprises a pulsed electrical signal, and the pulsed electrical signal is monophasic or biphasic.

[0213] 11. The method of embodiment 10, wherein the change in polarization or phase delay of the light is in response to a pulsed electrical signal delivered to the tissue.

[0214] 12. The method of embodiment 11, wherein the characteristics of the pulsed electrical signal are selected by a user of the catheter, the characteristics including the frequency, amplitude, and duration of the pulsed electrical signal.

[0215] 13. The method of any one of aspects 9 to 12, wherein the energy comprises radio frequency (RF) and the energy source comprises an RF energy source.

[0216] 14. The method of any one of aspects 9 to 13, wherein the catheter includes a shaft with a multimode transmission medium disposed therein, the multimode transmission medium being used to enable the use of tissue spectrometry to determine the depth of an anatomical structure within a patient.

[0217] 15. A catheter for ablating tissue of a cardiac wall, the catheter comprising: A proximal end portion; A distal end portion. a plurality of electrodes disposed on the distal end at predetermined distances from one another; at least one optical port positioned on the distal end at a predetermined location relative to the plurality of electrodes; Including, The catheter is configured to be placed within the outer sheath such that the distal end assumes a straight configuration compatible with vascular delivery, the distal end assuming a circular shape when pushed through the sheath; the plurality of electrodes are connected by wires to an external electrical energy generating device via an electrical connector on the proximal end of the catheter; the plurality of electrodes are configured to deliver electrical energy to the heart wall when excited by an external electrical energy generating device; The catheter, wherein at least one optical port includes an optical component connected by an optical fiber to an external optical energy generating device via an optical connector on a proximal end of the catheter, the optical component configured to project optical energy into the heart wall when excited by the optical energy generating device, configured to receive back reflected optical energy from the heart wall, and configured to transport the reflected optical energy through the optical fiber and the optical connector to an external optical sensing device.

[0218] 16. The catheter of aspect 15, wherein the circular shape of the distal end lies in a plane parallel to the heart wall and is configured to contact the heart wall.

[0219] 17. A catheter described in embodiment 15 or embodiment 16, wherein the location of the at least one optical port is selected for optimal observation of optical parameter changes caused by tissue ablation by excitation of multiple electrodes.

[0220] 18. A catheter described in any one of aspects 15 to 17, wherein the electrical energy delivered by the external electrical energy generating device comprises a pulsed electrical signal.

[0221] 19. The catheter of aspect 18, wherein the pulsed electrical signal is monophasic or biphasic.

[0222] 20. A catheter described in any one of aspects 15 to 19, wherein the electrical energy delivered by the external electrical energy generating device comprises radio frequency (RF) energy. [Explanation of symbols]

[0223] 100 Catheters 101 Console 102 Ablation Energy Source 103 Cooling Source 104 User Interface 105 Optical Fiber 106 Electrical cabling, wires 107 patients 200 Proximal Section 201 Distal Section 202 Shaft 204 Wiring 205 Connector 213 External electrode 214 Catheter tip 215 Radiopaque Markers 216 Irrigation Orifice 300 Lens 301 Same plane 302 Surface 303 Recess 304 Splitting Element 305 Glue, adhesive 306 Central Cooling Channel 307 Cooling Communication Path 308 Optical Viewport 400 Petal-shaped composition 401 Loop Configuration 402 3D sphere configuration 403 Spiral structure 404 Spiral structure 500 optical circuit 502 Optical Source 504 Splitting Element 506 Sample Arm 508 Reference Arm 510 Samples 512 Delay Unit 514 Detector 600 Myocardial Tissue 601 Non-ablated area 602 PFA Ablated Tissue 603 Gap 604 cell nucleus 800 PFA-OCR Catheter 801 Main unit 802 Electrode 802A electrode 802B electrode 803 Optical Port, Aperture 803A opening 803B opening 901 Endocardial wall 902 Wire Lumens 903 Optical Lumens 1001 Optical catheter 1002 Optical Energy 1003 Opening 1101 Groove 1102 Tongue 1201 Catheter body 1202 Fiber Optic Cable 1203 Lens 1203B Lens 1204 Mirror 1401 Outer catheter 1402 Inner Catheter 1500 Outer Catheter 1501 Main body 1502 Electrode 1503 Opening 1504 Inner Catheter 1505 Catheter body 1506 Electrode 1508 Wire Lumen 1509 Wire 1510 Internal mechanical structure 1511 Groove 1512 Tongue 2100 PFA-OCR Catheter 2101 Outer catheter 2102 Inner Optical Catheter 2103 Opening 2103B opening 2104 Optical Assembly 2104A Optical Assembly 2104B Optical Assembly 2104C Optical Assembly 2105 Optical Fiber 2106 Opening 2106A opening 2106B opening 2106C opening 2107B Input optical energy 2108B Optical Energy 2300 Computer Systems 2302 User Input / Output Interface 2303 User Input / Output Devices 2304 processor 2306 Communications Infrastructure 2308 Main Memory 2310 Secondary Memory 2312 Hard Disk Drive 2314 Removable Storage Drive 2318 Removable Storage Unit 2320 Interface 2322 Removable Storage Unit 2324 Communication Interface 2326 Communication Path 2328 Remote Devices, Networks, and Entities

Claims

1. 1. A system comprising: A catheter comprising: Proximal section, Distal section, a shaft coupled between the proximal section and the distal section; and a catheter including an optical circuit configured to at least partially transport light from the proximal section to the distal section and vice versa; a pulsed field ablation energy source coupled to the catheter and configured to deliver a pulsed electrical signal to the tissue sample; Processing device and Including, The processing device comprises: analyzing one or more optical signals received from the optical circuit to determine a change in polarization or phase delay of light reflected or scattered by the tissue sample; configured to determine a change in birefringence of the tissue sample based on the change in polarization or phase retardation; The change in polarization or phase delay of the light reflected or scattered by the tissue sample is responsive to the pulsed electrical signal transmitted to the tissue sample.

2. 2. The system of claim 1, wherein the optical circuit is configured to transport light at least partially from the proximal section to the distal section and vice versa, at least partially using a polarization-maintaining transmission medium in the shaft.

3. The system of claim 1 , wherein the pulsed electrical signal delivered by the pulsed field ablation energy source is monophasic or biphasic.

4. The system of claim 1 , wherein the one or more optical signals include an optical coherence tomography (OCT) signal or an optical coherence reflectometry (OCR) signal acquired by the tissue sample.

5. The system of claim 1 , wherein the optical circuit is configured to transmit the light from the distal section to the tissue sample.

6. The system of claim 1 , wherein the distal section of the catheter includes a plurality of optical ports configured to collect the light reflected or scattered from the tissue sample.

7. The system of claim 1 , wherein characteristics of the pulsed electrical signal are selected by a user of the catheter, the characteristics including a frequency, an amplitude, and a duration of the pulsed electrical signal.

8. The catheter, a plurality of electrodes disposed on the distal section at predetermined distances from one another; at least one optical port positioned on the distal section at a predetermined location relative to the plurality of electrodes; Further comprising: the catheter is configured to be placed within an outer sheath such that the distal section assumes a straight configuration compatible with vascular delivery, the distal section assuming a circular shape when pushed through the outer sheath; the plurality of electrodes are configured to be connected by wires to the pulsed field ablation energy source via an electrical connector on the proximal section of the catheter; the plurality of electrodes are configured to deliver electrical energy to a tissue sample when excited by the pulsed field ablation energy source; the at least one optical port includes an optical component, the optical component being connected by an optical fiber to the optical circuit via an optical connector on the proximal section of the catheter; The optical component comprises: projecting optical energy into the tissue sample when excited by the optical circuit; receiving optical energy reflected from the tissue sample; The system of claim 1 , configured to transport the reflected optical energy through the optical fiber and the optical connector to the processing device.

9. The system of claim 8 , wherein the circular shape of the distal section lies in a plane parallel to the tissue sample and is configured to contact the tissue sample.

10. The system of claim 8 , wherein a location of the at least one optical port is selected for optimal observation of optical parameter changes caused by tissue ablation by excitation of the multiple electrodes.

11. The system of claim 8 , wherein the pulsed electrical signal is monophasic or biphasic.

12. The system of claim 8, wherein the tissue sample is a cardiac wall.

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