Ultrasound imaging system and method

Abstract

An intracardiac echocardiogram (ICE) imaging system is disclosed, including an ICE catheter having a longitudinal axis, a proximal end, and a distal end. The ICE catheter corresponds to a microelectromechanical (MEMS) or other transducer-based phased-array ultrasound catheter having an outer diameter of 2 mm (6 French) or less for delivery into a cardiac chamber through the internal jugular, subclavian, axillary, or innominate venous system for lead placement of a pacemaker or other implantable cardioverter-defibrillator (ICD) device. The catheter shaft further contains an electronic flex cable in communication with at least one signal trace, configured to direct a plurality of transducer array elements to transmit and receive ultrasound beams, receive at least one signal from the plurality of transducer array elements, and construct at least one image of at least a portion of the heart based on the at least one signal.

Description

[Technical Field]

[0001] The present disclosure relates generally to the field of intracardiac echocardiogram (ICE) or ultrasound imaging systems. More specifically, some embodiments relate to the use of a sub-2.0 mm (6 French) phased array ultrasound catheter for subclavian delivery for lead placement of a defibrillator device. [Background technology]

[0002] The use of catheter-based structural and electrophysiology procedures has recently expanded to more complex scenarios, making accurate identification of various anatomical structures within each individual heart key to achieving optimal outcomes. Intracardiac echocardiography (ICE) is a specialized imaging technique for high-resolution, real-time visualization of cardiac structures, continuous monitoring of catheter position within the heart, and early detection of procedural complications such as pericardial effusion and thrombus formation. Due to the size of the catheter (2.7 mm (8 Fr) or larger), access is typically via the femoral vein. Furthermore, ICE imaging offers additional advantages, including excellent patient tolerance, reduced fluoroscopy time, and the elimination of the need for general anesthesia or a second operator. Currently, ICE imaging has replaced transesophageal echocardiography as the ideal imaging technique for guiding certain procedures, such as atrial septal defect closure and catheter ablation of arrhythmias, and is also playing an emerging role in other procedures, such as mitral valvuloplasty, transcatheter aortic valve replacement, and left atrial appendage closure.

[0003] In electrophysiology procedures, ICE imaging technology allows for the integration of real-time images with electroanatomical maps. ICE imaging plays a role in the evaluation of arrhythmogenic substrates and is particularly useful for mapping structures not visualized by fluoroscopy, such as the atrial or ventricular septum, papillary muscles, and intracavitary muscular ridges. For these reasons, ICE has replaced transesophageal echocardiography (TEE). Furthermore, the introduction of ICE represents a major advancement in cardiac imaging and has become an integral part of various percutaneous interventional and electrophysiology procedures, potentially leading to improved outcomes and reduced risks. ICE allows for real-time assessment of cardiac anatomy during interventional procedures and guides catheter manipulation through various anatomical structures.

[0004] In contrast to TEE, ICE is performed under conscious sedation by the primary interventional operator and does not require endotracheal intubation, thereby eliminating the risk of esophageal trauma and other postanesthetic consequences. Furthermore, ICE reduces fluoroscopic radiation exposure to both the patient and the operator, potentially improving outcomes, shortening procedure time, and facilitating early detection of complications such as thrombus formation and pericardial effusion. Therefore, improved ICE imaging systems using ultrasound ICE catheters are needed.

[0005] Currently available ICE catheters cannot access these small vascular structures. Avoiding femoral access not only potentially provides a more favorable outcome for the patient, but also allows for faster post-procedure mobility and eliminates the risk of retroperitoneal bleeding.

[0006] These techniques minimize the need for and use of fluoroscopy, thereby reducing the harmful effects of ionizing radiation on the patient and operator. Additionally, because fluoroscopy does not allow visualization of soft tissue structures, when the lead helix is ​​placed in myocardial tissue, ICE allows direct visualization of the helix as it is positioned within the atrial and ventricular tissue. Summary of the Invention

[0007] First, the preferred embodiment described below involves the use of a MEMS-based or bulk PZT-based phased-array transducer-enabled ultrasound catheter with an outer diameter of 2.0 mm (6 French) or less for delivery into a cardiac chamber through the internal jugular, subclavian, axillary, or innominate venous system for the purpose of visualizing lead placement of a pacemaker or other implantable cardioverter-defibrillator (ICD) device. The intracardiac echocardiogram (ICE) imaging system includes an ICE catheter having a longitudinal axis, a proximal end, and a distal end. Furthermore, an ultrasound transducer array is integrated into the distal end of the ICE catheter. The ultrasound transducer array includes a plurality of transducer array elements disposed on a substrate. It will be appreciated that the plurality of transducer array elements correspond to microelectromechanical (MEMS)-based piezoelectric micromachined ultrasound transducers (pMUTs). The ICE imaging system further includes a catheter shaft connected at one end to a handle assembly and at the other end to the ultrasound transducer array. The catheter shaft encloses an electronic flex cable in communication with at least one signal trace, the cable being configured to direct each of the plurality of transducer array elements to transmit and receive multiple ultrasound beams to and from the heart via the at least one signal trace, the multiple ultrasound beams having a bandwidth that includes a predetermined fundamental mode vibration of each of the plurality of transducer array elements, allowing a single array element to simultaneously transmit and receive multiple fundamental mode vibrations; receive at least one signal from the plurality of transducer array elements based on the transmission and reception of at least one ultrasound beam of the plurality of ultrasound beams; and construct at least one image of at least a portion of the heart based on the at least one signal.

[0008] The ICE imaging system further includes an imaging device coupled to the ICE catheter using a custom dongle. The custom dongle is coupled to the handle assembly using an interposer and a flat circuit board. The custom dongle is configured to communicate ultrasound transmit pulses and ultrasound receive waveforms between the ICE catheter and the imaging device. The ICE imaging system further includes a steering control unit disposed within the handle assembly for articulating the distal tip of the ICE catheter and directing the face of the ultrasound transducer array to an internal view, including an anterior or posterior position of the heart. It can be seen that the distal tip of the ICE catheter is coated with a material that provides electrical insulation and transmission of ultrasound signals.

[0009] In one embodiment, an intracardiac echocardiogram (ICE) catheter is disclosed. The ICE catheter includes a body having a longitudinal axis and a distal end. An ultrasound transducer array is disposed within the distal end of the body. The ICE catheter is 2.0 mm (6.0 French) or smaller, thereby enabling access to the heart and vascular structures. The ultrasound transducer array includes a plurality of transducer array elements disposed on a substrate. The plurality of transducer array elements can be seen to correspond to microelectromechanical (MEMS)-based piezoelectric micromachined ultrasound transducers (pMUTs). Each of the plurality of transducer array elements includes individual elements of multiple diameters. The ultrasound transducer array is connected in series between at least one signal trace and a common ground. Each transducer array element includes a plurality of transducers, with a first transducer array element including a first group of two or more transducers and a second transducer array element including a second group of two or more transducers. Each of the plurality of transducer array elements includes a plurality of transducer cells connected in parallel. It will be appreciated that the plurality of transducer array elements corresponds to the plurality of pMUT elements. The plurality of transducer cells corresponds to the pMUT cells connected in a parallel configuration in each of the plurality of pMUT elements. In one embodiment, the plurality of pMUT cells have multiple diameters to achieve a wide bandwidth. Furthermore, at least one first electrode is connected between the at least one piezoelectric layer and the signal conductor, and at least one second electrode is connected between the at least one piezoelectric layer and the ground line.

[0010] In one embodiment, an intracardiac echocardiogram (ICE) imaging system is disclosed. The ICE imaging system includes an ICE catheter having a longitudinal axis, a proximal end, and a distal end. Furthermore, a microelectromechanical systems (MEMS)-based piezoelectric micromachined ultrasound transducer (pMUT) array is disposed within the distal end of the ICE catheter. The MEMS-based pMUT array includes a plurality of MEMS-based pMUT array elements disposed on a substrate. The ICE imaging system also includes an electronics flex cable having one end connected to the handle assembly and another end connected to the MEMS-based pMUT array. The electronics flex cable is configured to communicate with at least one signal trace and to direct each of the plurality of MEMS-based pMUT array elements to transmit and receive a plurality of ultrasound beams relative to the heart via the at least one signal trace, to receive at least one signal from the plurality of MEMS-based pMUT array elements based on the transmission and reception of at least one of the plurality of ultrasound beams, and to construct at least one image of at least a portion of the heart based on the at least one signal.

[0011] In one embodiment, a method is disclosed for deploying an ICE catheter into a heart chamber through the internal jugular / subclavian / axillary / innominate vein system. The ICE catheter is 2.0 mm (6.0 French) or smaller, thereby providing access to the heart and vascular structures. The ICE catheter includes an ultrasound transducer array having a plurality of transducer array elements. The method includes directing the plurality of transducer array elements to transmit and receive a plurality of ultrasound beams to and from the heart via at least one signal trace; receiving at least one signal from the plurality of transducer array elements based on the transmission and reception of at least one of the plurality of ultrasound beams; and constructing at least one image of at least a portion of the heart chamber based on the at least one signal. In one embodiment, the ICE catheter is 2.0 mm (6 French) or smaller.

[0012] In another embodiment, a method for deploying an ICE catheter having an ultrasound transducer array with a plurality of transducer array elements within a heart chamber using arterial access is disclosed, the method including directing the plurality of transducer array elements to transmit and receive a plurality of ultrasound beams to and from the heart via at least one signal trace, receiving at least one signal from the plurality of transducer array elements based on the transmission and reception of at least one of the plurality of ultrasound beams, and constructing at least one image of at least a portion of the heart chamber based on the at least one signal.

[0013] In another embodiment, a method is disclosed for visualizing lead location and facilitating lead / device delivery using a 2.0 mm (6 French) or smaller ICE catheter. The lead location is for a pacemaker or other implantable cardioverter defibrillator (ICD) lead. The method further includes using a 2.0 mm (6 French) or smaller ICE catheter to visualize the arterial system for device delivery, including, but not limited to, heart valve surgery, vascular surgery, and left heart surgery.

[0014] Other features and aspects of the present disclosure will become apparent from the following description and accompanying drawings. [Brief explanation of the drawings]

[0015] The accompanying drawings illustrate various embodiments of systems, methods, and embodiments of various aspects of the present disclosure. Those skilled in the art will understand that the boundaries of elements illustrated in the figures (e.g., boxes, groups of boxes, or other shapes) represent one example of various boundaries representative of the disclosed invention. In some examples, one element may be designed as multiple elements, or multiple elements may be designed as one element. In other examples, an element shown as an internal component of one element may be implemented as an external component of another element, and vice versa. Additionally, elements may not be drawn to scale. A non-limiting and non-exhaustive description of the present disclosure is provided with reference to the following drawings. The components in the figures are not necessarily to scale, with emphasis instead being placed on the principles being described.

[0016] Various embodiments will now be described with reference to the accompanying drawings, which are provided for illustrative purposes and are not intended to limit the scope of the present disclosure, in which like designations indicate like elements. [Figure 1] 1 shows a conventional imaging system for acquiring two-dimensional image information. [Figure 2] 1 shows a conventional imaging system for acquiring two-dimensional image information. [Figure 3] 1 shows a schematic diagram of an intracardiac echo (ICE) imaging system according to one embodiment of the present disclosure. [Figure 4] FIG. 1 shows a schematic front view of an intracardiac echo (ICE) catheter and custom dongle according to one embodiment of the present disclosure. [Figure 5] FIG. 1 shows a perspective view of a custom dongle for connecting an ICE catheter and an imaging device according to one embodiment of the present disclosure. [Figure 6A] 1 illustrates a flat circuit board with an electronic flex cable according to one embodiment of the present disclosure. [Figure 6B] FIG. 1 illustrates a proximal view of an interposer with a board edge connector disposed within a custom dongle, according to one embodiment of the present disclosure. [Figure 6C]1 illustrates a side view of an interposer with multiple in-line connectors and circuit pins disposed on a printed circuit board (PCB) according to one embodiment of the present disclosure. [Figure 6D] 1 illustrates a distal view of an interposer with circuit pins for coupling the interposer to an electronic flex cable in a custom dongle, according to one embodiment of the present disclosure. [Figure 6E] 1 illustrates a PCB connected to an interposer according to one embodiment of the present disclosure. [Figure 6F] 1 illustrates a PCB disposed within a catheter handle with multiple in-line connection pads, according to one embodiment of the present disclosure. [Figure 7] 1A-1C show schematic diagrams of an ICE catheter with its distal tip redirected to forward and rearward positions using a steering control unit, according to one embodiment of the present disclosure. [Figure 8] 1 illustrates multi-channel electronic communication between an imaging device and an ultrasound transducer array of an ICE catheter, according to one embodiment of the present disclosure. [Figure 9] 1 shows a cross-sectional view of the distal end of an ICE catheter with multiple transducer array elements, according to one embodiment of the present disclosure. [Figure 10] 1 shows a schematic diagram of an ICE catheter having a flexible sheath with marker bands, according to one embodiment of the present disclosure. [Figure 11] 1 shows a schematic diagram of an ICE catheter having an electrically insulated shaft up to an imaging window at the distal end of the ICE catheter, according to one embodiment of the present disclosure. [Figure 12] FIG. 1 shows a schematic diagram illustrating the proximal side of a catheter handle assembly coupled to the distal side of a dongle handle assembly using pogo pins and a flat circuit board, according to one embodiment of the present disclosure. [Figure 13] 1 shows a cross-sectional image of a heart with a pacemaker lead placed within the heart, according to one embodiment of the present disclosure. [Figure 14] 1 shows another cross-sectional view of the heart with an ICE catheter positioned in the right ventricle. DETAILED DESCRIPTION OF THE INVENTION

[0017] Detailed Description The components of the embodiments generally described and illustrated in the figures herein can be arranged and designed in a wide variety of configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the disclosure, but is merely representative of various embodiments. While various aspects of the embodiments are illustrated in the drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0018] Some embodiments of the present disclosure will now be described in detail, showing all of their features. Words such as "comprises," "has," "contains," and other forms thereof are intended to be equivalent and open-ended in that the items following any of these words are not intended to be an exhaustive list of such items, nor are they intended to be limited to only the listed items.

[0019] It should also be noted that, as used in this specification and the appended claims, the singular forms "a," "the," and "the" include the plural forms unless the context indicates otherwise. Although any systems and methods similar or equivalent to those described herein can be used in practicing or testing embodiments of the present disclosure, the preferred systems and methods are described herein. The terms "proximal" and "distal" are opposite terms. For example, the distal end of a device or component is the end of the component that is farthest from the practitioner during normal use. The proximal end refers to the opposite end, i.e., the end closest to the practitioner during normal use.

[0020] Embodiments of the present disclosure are described in more detail below with reference to the accompanying drawings, in which like elements are designated by like numerals throughout the several views and illustrative embodiments are shown. However, embodiments of the present disclosure may be implemented in alternative forms and should not be construed as being limited to the embodiments set forth herein. The examples described herein are non-limiting examples and are merely some examples among other possible examples.

[0021] 1 and 2 illustrate a prior art imaging system 100. The imaging system 100 may be used for diagnosis and / or treatment in combination with another imaging technique, such as X-ray, fluoroscopy, magnetic resonance, computed tomography, or an optical system. It is understood that an imaging technique generates an image that assists a physician by scanning a patient. Furthermore, the imaging system 100 provides an ultrasound transmit pulse 102 and an ultrasound receive path 104 for connection to an ultrasound transducer (not shown). The ultrasound transmit pulse 102 can transmit an ultrasound signal from the imaging system 100 toward a target, such as a patient's heart. Furthermore, the ultrasound receive path 104 can generate a waveform based on at least the ultrasound signal. The imaging system 100 can then convert the received ultrasound signal or ultrasound information into a two-dimensional (2D) image of the target or a portion of the target.

[0022] 3 shows a schematic diagram of an intracardiac echocardiogram (ICE) imaging system 300 according to one embodiment of the present disclosure. FIG. 3 will be described in conjunction with FIGS. The ICE imaging system 300 can be implemented for electrophysiology (EP). It can be used for diagnosis and / or treatment in combination with another imaging technique, such as x-ray, fluoroscopy, magnetic resonance, computed tomography, or optical systems. Both imaging techniques scan the patient to generate images that assist physicians. Data from different techniques can be aligned by placing markers with known spatial relationships to ultrasound scans within the images of the other technique. In other embodiments, the ICE imaging system 300 can use a catheter without markers and / or another imaging technique. In one embodiment, the ICE imaging system 300 can utilize a microelectromechanical (MEMS) transducer array, defined as a piezoelectric micromachined ultrasound transducer (pMUT), or other types of MEMS transducers interconnected using matched flexible circuitry. In one embodiment, the ICE imaging system 300 can correspond to an ultrasound imaging system. In one embodiment, the ICE imaging system 300 can correspond to an intravascular MEMS ultrasound transducer that utilizes high-density flexible circuitry for all transmission and electrical interconnections. In one embodiment, ICE imaging system 300 is used to treat patients with cystic fibrosis (CF). It has been found that the use of high density flexible circuitry can provide highly repeatable and stable transmit and return signals. Furthermore, high density flexible circuit transmission lines can transmit electrical energy from one end of ICE imaging system 300 to the other distal end.

[0023] The present invention discloses the use of a MEMS-based or bulk PZT-based phased array transducer-enabled ultrasound catheter with an outer diameter of 2.0 mm (6 French) or less for delivery into a cardiac chamber through the internal jugular, subclavian, axillary, or innominate venous systems for the purpose of visualizing lead placement of a pacemaker or other implantable cardioverter-defibrillator (ICD) device.

[0024] 3, an ICE imaging system 300 may include an imaging device 302 coupled to an ICE catheter 304 via a communication channel 306. In one embodiment, communication channel 306 may be a cable and bus connection or a custom dongle with multiple connections. Hereinafter, communication channel 306 may be referred to as custom dongle 306.

[0025] In one embodiment, ICE catheter 304 corresponds to an ultrasound catheter. ICE catheter 304 is positioned within a patient's heart chamber, and imaging device 302 can receive at least one signal from ICE catheter 304. The at least one signal is communicated from ICE catheter 304 to imaging device 302 via custom dongle 306. Furthermore, imaging device 302 can include an image processor 308, a transmit beamformer 310, a receive beamformer 312, and a display 314.

[0026] The image processor 308 may be configured to generate two-dimensional (2D) images according to the data received from the ICE catheter 304. In one embodiment, the image processor 308 may be configured to receive focused signals from the receive beamformer 312. The image processor 308 may render the data to construct an image or image sequence. In one embodiment, the image may be a three-dimensional (3D) representation, such as a two-dimensional image rendered from a line of sight selected by a user or a processor. In one embodiment, the image processor 308 may be a detector, filter, processor, application specific integrated circuit, field programmable gate array, digital signal processor, control processor, scan converter, three-dimensional image processor, graphics processing unit, analog circuit, digital circuit, or combination thereof. The image processor 308 may receive the beamformed data and generate an image to display on the display 314. It is understood that the generated image is associated with a two-dimensional (2D) scan. Alternatively, the generated image may be a three-dimensional (3D) representation.

[0027] The image processor 308 may be programmed for hardware-accelerated two-dimensional reconstruction. The image processor 308 may store processed data of at least one signal and an image sequence in memory. In one embodiment, the memory may be a non-transitory computer-readable storage medium. Instructions for implementing the processes, methods, and / or techniques described herein may be provided by a computer-readable storage medium or memory, such as a cache, buffer, RAM, removable media, a hard drive, or other computer-readable storage medium. Non-transitory computer-readable storage media include various types of volatile and non-volatile storage media. The functions, operations, or tasks illustrated in the figures or described herein are performed in response to one or more instruction sets stored in a computer-readable storage medium. The functions, operations, or tasks are not dependent on a particular type of instruction set, storage medium, processor, or processing strategy and may be performed by software, hardware, integrated circuits, firmware, microcode, etc., operating alone or in combination.

[0028] The transmit beamformer 310 may be configured to transmit electrical signals or electrical impulses in the form of at least one signal toward the ICE catheter 304. The receive beamformer 312 may be configured to receive the electrical signals or electrical impulses from the ICE catheter 304. In one embodiment, the transmit beamformer 310 and the receive beamformer 312 may facilitate transmit beamforming techniques to focus energy toward the receiver to improve the signal-to-noise ratio (SNR) of the at least one signal, which is then transmitted to the image processor 308.

[0029] Display 314 may be configured to display an image or sequence of images while or after the data is being rendered by image processor 308. The image may be a 3D representation, such as a two-dimensional image rendered from a viewing direction selected by a user or a processor. Alternatively, the image may be one or more two-dimensional images representing a plane within a volume. In one embodiment, display 314 may be part of imaging device 302 or may be remote, such as a networked display. In one embodiment, display 314 may be a cathode ray tube (CRT), liquid crystal display (LCD), projector, plasma, or other display device now known or later developed.

[0030] The ICE catheter 304 can electronically communicate with the imaging device 302 to transmit and receive ultrasound signals to and from a vessel wall or structure of interest. In one embodiment, the ICE catheter 304 is configured for standard echocardiographic visualization of the heart; for example, a standard version may visualize the right atrium. Visualization performed using the ICE catheter 304 is described in conjunction with FIGS. 13 and 14 . The ICE catheter 304 can be used for transseptal catheterization for several percutaneous interventions, such as left heart catheter ablation and atrial septal defect closure as an effective alternative to surgical intervention. Furthermore, the ICE catheter 304 can include a body 316 having a longitudinal axis 318, a proximal end 320, a distal end 322, a handle assembly 324, a steering control unit 326, a distal tip 328, and a dongle cable 330.

[0031] A handle assembly 324 can be disposed between the proximal end 320 and the distal tip 328 of the ICE catheter 304. Additionally, a steering control unit 326 can be disposed within the handle assembly 324. The steering control unit 326 can be provided for articulating the distal tip 328 of the ICE catheter 304. Furthermore, the steering control unit 326 can orient the face of the ultrasound transducer array (not shown) to various positions relative to the ICE catheter 304. Furthermore, the steering control unit 326 can include a steering handle 332 and a housing 334 that houses an actuator (not shown) and a steering hub (not shown). It can be seen that internal friction occurs between the actuator and the steering hub, and between the actuator and the housing 334, thereby maintaining the ICE catheter 304 in an adjusted configuration without the operator's attention. Rotating the steering handle 332 can facilitate positioning of the distal tip 328 of the ICE catheter 304. Movement of the distal tip 328 by the steering control unit 326 is shown in FIG. 7 . In one embodiment, the steering handle 332 can be rotated to position the distal tip 328 within the patient's ventricle. In one embodiment, the steering control unit 326 can include a set of steering lines controlled by a steering actuator to bidirectionally articulate the distal segment of the ICE catheter 304. It can be seen that the steering handle 332 can rotate from 0 degrees to + / - 45 degrees. A catheter shaft 336 is coupled at one end to the handle assembly 324 and at the other end to the distal tip 328 of the ICE catheter 304. Additionally, the catheter shaft 336 can house an electronic flex cable (not shown) and multiple steering cables (not shown). In one embodiment, the electronic flex cable can be a stainless steel cable. The electronic flex cable can be coupled at one end to the handle assembly 324 and at the other end to the ultrasound transducer array. The electronic flex cable and multiple steering cables are described below in conjunction with Figures 6A-7.Further, the ICE catheter 304 is described in conjunction with FIG.

[0032] Referring to FIG. 4 , the ICE catheter 304 may include an ultrasound transducer array 402, a substrate 404, an interposer 406, and a flat circuit board 408. The ultrasound transducer array 402 may be disposed within the distal tip 328 of the ICE catheter 304. In one embodiment, the ultrasound transducer array 402, the substrate 404, the interposer 406, and the flat circuit board 408 may correspond to a flexible printed electronic circuit for communicating from the distal end 322 of the ICE catheter to a dongle cable 330 or directly to the ICE imaging system 300. The ultrasound transducer array 402 may be disposed on the substrate 404 at the distal end 328 of the ICE catheter 304. It will be appreciated that the ultrasound transducer array 402 may correspond to a MEMS-based pMUT array. The handle assembly 324 may be connected to the proximal end 320 of the ICE catheter 304 using the interposer 406 and the flat circuit board 408. In one embodiment, the handle assembly 324 can be connected to the dongle cable 330 using a catheter handle (not shown) and an interposer 406, which is described below in conjunction with Figures 6B-6D. It can be seen that the interposer 406 can be coupled to the custom dongle 306, and the flat circuit board 408 can be coupled to the proximal end 320 of the ICE catheter 304, on the handle assembly 324 side.

[0033] As shown in FIGS. 3-4 , the catheter shaft 336 may be coupled between the handle assembly 324 and the ultrasound transducer array 402. An electronic flex cable within the catheter shaft 336 may receive at least one signal from the ultrasound transducer array 402 and transmit the received signal back to the imaging device 302 via the custom dongle 306. The electronic flex cable may be coupled at one end to the handle assembly 324 and at the other end to the ultrasound transducer array 402. It can be seen that the ultrasound transducer array 402 can receive electrical signals from the imaging device 302 via the custom dongle 306 and the electronic flex cable. It can also be seen that the ultrasound transducer array 402 can transmit at least one signal back to the imaging device 302 for further analysis of the at least one signal for image generation. Furthermore, the ICE catheter 304 may be coupled to the ICE imaging device 302 using the dongle cable 330. Additionally, the interposer 406 and flat circuit board 408 may be coupled using male and female circuit pins, as shown in Figures 5 and 6A.

[0034] 5 , a perspective view of a custom dongle 306 for communication between an ICE catheter 304 and an imaging device 302 is shown, in accordance with one embodiment of the present disclosure. It can be seen that the custom dongle 306 is a communication channel for transmitting and receiving electrical energy or electrical impulses between the distal tip 328 of the ICE catheter 304 and the imaging device 302. The custom dongle 306 can include a dongle handle terminal 502, a dongle cable 330, and a dongle device terminal 504. The dongle handle terminal 502 can be connected to the handle assembly 324 of the ICE catheter 304 using an interposer 406 and a flat circuit board 408. In one embodiment, the dongle handle terminal 502 can receive the interposer 406, and the handle assembly 324 can hold the flat circuit board 408.

[0035] As shown in FIG. 5 , the interposer 406 may include a printed circuit board 506 and a plurality of pogo pins 508 disposed on the printed circuit board 506. It is understood that the plurality of pogo pins 508 may function as male connection points coupled to the flat circuit board 408. As shown in FIG. 6A , the flat circuit board 408 may be coupled to an electronic flex cable 602. The flat circuit board 408 may include a plurality of landing pads 604. The plurality of landing pads 604 may be disposed on the flat circuit board 408. The plurality of landing pads 604 may be configured to receive the plurality of pogo pins 508. It is understood that the plurality of landing pads 604 of the flat circuit board 408 may be press-fit onto the plurality of pogo pins 508 of the printed circuit board 506. The electronic flex cable 602, one end of which is coupled to the flat circuit board 408, may be coupled to the distal end 322 of the ICE catheter 304 at the other end. Additionally, the dongle device terminal 504 may be coupled to the imaging device 302. The imaging device 302 may receive at least one signal and acoustic echo from the ultrasound transducer array 402 via the dongle cable 330.

[0036] Additionally, the ICE catheter 304 may be configured to transmit ultrasound signals into the interior of the subject. In one embodiment, the ICE catheter 304 may be a flexible, elongated member including a body 316 having a longitudinal axis 318, a proximal end 320, and a distal end 322. Additionally, the body 316 may include an ultrasound transducer array 402 disposed within the distal end 322 of the ICE catheter 304.

[0037] 6B-6E , an interposer 406 is disclosed that includes a board edge connector 606 positioned within the custom dongle 306 toward the dongle handle terminals 502. The board edge connector 606 may correspond to an in-line printed circuit board (PCB) connector. In one embodiment, the board edge connector 606 is a standard board edge connector attached to a circular PCB within the custom dongle 306 toward the dongle handle terminals 502. The interposer 406 may include proximally facing connector pins 608 that can be soldered to connect to the dongle cable 330 within the custom dongle 306. Furthermore, the board edge connector 606 may be positioned on the interposer 406 from one side, and the connector pins 608 may be positioned on the interposer 406 from the other side. In one embodiment, the connector pins 608 may be removably coupled to the dongle cable 330 using a different solder connection. In another embodiment, as shown in FIGS. 6E-6F, the board edge connector 606 can be removably coupled to the handle assembly 324 using a PCB 610.

[0038] The handle assembly 324 may include a PCB 610 toward the proximal end 320 of the ICE catheter 304, as shown in FIGS. 6E-6F . Furthermore, the PCB 610 may include a plurality of vias 612 disposed on one side of the PCB 610 and a plurality of in-line connection pads 614 disposed on the other side of the PCB 610. Furthermore, the plurality of in-line connection pads 614 may be disposed within a board edge connector 606 of the interposer 406. It can be seen that the plurality of in-line connection pads 614 may be rectangular grooved portions. The board edge connector 606 can receive the plurality of in-line connection pads 614 when the dongle handle terminals 502 of the custom dongle 306 are coupled to the handle assembly 324 toward the proximal end 320 of the ICE catheter 304. In one embodiment, the plurality of in-line connection pads 614 of the PCB 610 can mate at one end with the board edge connector 606 of the interposer 406. In another embodiment, multiple vias 612 may be used to terminate connections to the other end of the catheter shaft 336. It is understood that multiple vias may correspond to multiple pads. Additionally, multiple vias 612 in the PCB 610 may be configured to receive multiple steering cables 616.

[0039] Additionally, the custom dongle 306 may be connected to the handle assembly 324 using an interposer 406 and a flat circuit board 408 disposed between the custom dongle 306 and the handle assembly 324. In one embodiment, the custom dongle 306 may be connected to the handle assembly 324 using a board edge connector 606. The custom dongle 306 may be configured to communicate ultrasonic transmit pulses and ultrasonic receive waveforms to the ultrasound transducer array 402. In one embodiment, the interposer 406 and the flat circuit board 408 may be referred to as a flexible circuit interposer, and the catheter shaft 336 may be referred to as a flexible circuit transmission line. It will be appreciated that at least one signal may be electrical energy transmitted to and / or from the catheter shaft 336 and the interposer 406 from the proximal end 320 to the distal end 322 of the ICE catheter 304. Additionally, the ultrasound transducer array 402 disposed within the distal end 322 of the ICE catheter 304 may convert electrical energy into non-acoustic pressure waves. Additionally, the acoustic echoes may be converted back into electrical energy and returned through the catheter shaft 336 from the distal end 322 to the proximal end 320 of the ICE catheter 304. The electrical energy or electrical pulses may be transmitted to the imaging device 302 for processing in the image processor 308.

[0040] In one embodiment, the catheter shaft 336, interposer 406, flat circuit board 408, and substrate 326 may be ultra-high density flexible circuits composed primarily of high-ductility copper on a polyimide-based substrate. It will be appreciated that ground returns and electromagnetic interference (EMI) shielding may be integrated into the flexible circuit transmission lines. In one embodiment, attachment of the catheter shaft 336 to the ultrasound transducer array 402 may utilize thermal compression adhesives and / or various metal solders. It will be appreciated that the use of flexible circuits, such as the catheter shaft 336, interposer 406, flat circuit board 408, and substrate 404, minimizes errors typically associated with traditional small gauge coaxial cables used in many modern imaging catheters.

[0041] Referring to FIG. 7, a schematic diagram of an ICE catheter 304 with a distal tip 328 being redirected to a forward position 702 and a rearward position 704 using a steering control unit 326 is disclosed, according to one embodiment of the present disclosure.

[0042] The steering control unit 326 can be disposed within the handle assembly 324 and can articulate the distal tip 328 of the ICE catheter 304 to orient the face of the ultrasound transducer array 402 toward an internal view including an anterior location 702 or a posterior location 704 of the heart. It is understood that the distal tip 328 of the ICE catheter 304 can correspond to the tip of the catheter shaft 336 of the ICE catheter 304. Furthermore, the ultrasound transducer array 402 can be disposed within the distal tip 328 of the ICE catheter 304. It is understood that the cable connecting the distal end 322 of the catheter handle to the distal tip 328 can be the catheter shaft 336. In one embodiment, the ultrasound transducer array 402 can be positioned to orient the internal view including the anterior location 702 and the posterior location 704 of the heart. The distal tip 328 of the ICE catheter 304 can be curved toward the distal end 322. In one embodiment, the distal tip 328 of the ICE catheter 304 can be coated with a material that provides electrical insulation and transmission of ultrasound signals. Additionally, a catheter shaft 336 communicating between the distal tip 328 and the distal end 322 of the ICE catheter 304 can transmit electrical signals or pulses to the distal tip 328 of the ICE catheter 304, and the ultrasound transducer array 402 can transmit acoustic echoes back to the imaging device 302 via the catheter shaft 336 and the custom dongle 306.

[0043] The plurality of steering cables 616 can be redirected to a forward position and a rearward position using the steering control unit 326, as shown in FIG. 7 . The plurality of steering cables 616 can be housed within a catheter shaft 336. In one embodiment, the steering control unit 326 can be used to redirect at least two of the plurality of steering cables 616 toward at least two distal tips equipped with ultrasound transducer arrays. Additionally, the catheter shaft 336 has a graded durometer 706 of Pebax® material toward the distal end 328 of the ICE catheter 304. It can be seen that the graded durometer 706 of the Pebax® material is hard and stiff toward the proximal end 320 of the catheter shaft 336 and softens toward the distal end 322. In one embodiment, the catheter shaft 336 can be softened over a range of at least 15-20 cm (6-8 inches) toward the distal end 322. It can be seen that the distal tip 328 can have a softer Pebax® material. Additionally, the plurality of steering cables 616 may be configured to bend or tilt the distal tip 328 when a steering handle of the steering control unit 326 is rotated clockwise or counterclockwise. It will be appreciated that an actuator of the steering control unit 326 may pull one of the plurality of steering cables 616 when inserted into the heart. One of the plurality of steering cables 616 may bend the distal tip 328 toward an anterior position and a posterior position within the heart. In one embodiment, at least two of the plurality of steering cables 616 may be bent using the steering control unit 326.

[0044] In one embodiment, the steering cables 616 may be made of a synthetic material such as nylon or similar synthetic fibers, or a plastic material such as urethane, Teflon®, Kynar®, Kevlar®, polyethylene, multi-strand nylon, gel-spun polyethylene fibers, etc. For example, the steering cables 616 may be multi-strand Spectra® brand nylon wire sold as Spiderwire® fishing line (10 pound test).

[0045] Referring to FIG. 8 , multi-channel electronic communication between an ICE imaging device 302 and an ultrasound transducer array 402 is disclosed in accordance with one embodiment of the present disclosure. The ultrasound transducer array 402 may include a plurality of transducer array elements 802 disposed on a substrate 404. Furthermore, each of the plurality of transducer array elements 802 may provide an individual focused beam of wide bandwidth. The ultrasound transducer array 402 may be connected to the ICE imaging device 302 using a dongle cable 330, as described above. The MEMS-based ultrasound transducer array 402 disposed within the distal end 322 of the ICE catheter 304 may transmit at least one signal to the imaging device 302 via an electronic flex cable 602 within the catheter shaft 336. The at least one signal may be an acoustic echo transmitted from the ultrasound transducer array 402. It can be seen that the acoustic echo of acoustic energy may be received from the face of the ultrasound transducer array 402 and received by the image processor 308.

[0046] Further, the plurality of steering cables 616 may be configured to cause each of the plurality of transducer array elements 802 to transmit and receive an ultrasound beam via at least one signal trace. The ultrasound beam may have a bandwidth that includes a predetermined fundamental mode vibration of each of the plurality of transducer array elements 802, thereby allowing a single array element to simultaneously transmit and receive multiple fundamental mode vibrations. It will be appreciated that the plurality of transducer array elements 802 may transmit and receive ultrasound beams to and from the heart or at least a portion of the heart. Furthermore, the electronics flex cable 602 within the catheter shaft 336 may be configured to receive at least one signal from the plurality of transducer array elements 802 based on the transmission and reception of at least one ultrasound beam of the plurality of ultrasound beams. The imaging device 302 may further be configured to construct at least one image of at least a portion of the heart based on the at least one signal. It will be appreciated that the electronics flex cable may be configured to display two-dimensional (2D) image information of the heart or at least a portion of the heart to the transmit beamformer 310 and the receive beamformer 312.

[0047] In one embodiment, the plurality of transducer array elements 802 may correspond to microelectromechanical (MEMS)-based piezoelectric micromachined ultrasound transducers (pMUTs). A catheter shaft 336 may be connected at one end to the handle assembly 324 and at the other end to the ultrasound transducer array 402. An electronic flex cable 602 within the catheter shaft 336 may be in communication with at least one signal trace. It can be seen that the electronic flex cable 602 may further be in communication with the transmit beamformer 310 and the receive beamformer 312 via the custom dongle 306 to display two-dimensional (2D) image information of the heart being scanned.

[0048] Referring to FIG. 9 , a cross-sectional view of the distal end 322 of an ICE catheter 304 having an ultrasound transducer array 402 with multiple transducer array elements 802 is shown, according to one embodiment of the present disclosure. The distal end 322 of the ICE catheter 304 may be provided with an ultrasound transducer array 402 having multiple transducer array elements 802. Furthermore, each of the multiple transducer array elements 802 may have multiple individual transducer cells 902 arranged to provide a wide bandwidth of the individual focused beam. In one embodiment, the ultrasound transducer array 402 may be comprised of a pMUT array including individual elements of different diameters. In one embodiment, to achieve a wider bandwidth in the pMUT array, pMUT cells of multiple diameters may be integrated into a single element. It can be seen that by arranging pre-formed pMUTs with various diameters, a wider bandwidth can be achieved through complex interactions between the individual pMUT elements. In one embodiment, the multiple diameter pMUT cells can achieve a bandwidth of over 55%. For example, there are five different dome diameters for three elements, and each array is a different size, such as 300 μm.

[0049] Furthermore, the ultrasound transducer array 402 may correspond to a pMUT, and the plurality of transducer array elements 802 may correspond to a plurality of pMUT elements. In one embodiment, the plurality of pMUT elements are directed to transmit and receive ultrasound beams having a bandwidth that includes a predetermined fundamental mode vibration of each of the plurality of pMUT elements, thereby allowing a single pMUT element to simultaneously transmit and receive multiple fundamental mode vibrations. Furthermore, the electronic flex cable 602 within the catheter shaft 336 receives at least one signal from the plurality of pMUT elements. It will be appreciated that the at least one signal may correspond to at least one ultrasound beam. The at least one signal may be transmitted to the ICE imaging device 302 for further processing by the image processor 308. The image processor 308 may construct at least one image of the heart. It will be appreciated that multiple pMUT elements may be used to create individual focused beams.

[0050] In an alternative embodiment, the ultrasound transducer array 402 may include a cover portion exhibiting a circular cross-section. It can be seen that the features of the ultrasound transducer array 402 are typical of an ICE imaging catheter. Due to the severe space limitations imposed by the small diameter of intracardiac catheters, ultrasound transducer arrays are typically limited to linear phased arrays composed of multiple individual transducer elements, such as 64 transducers or elements. The transducers have flat surfaces for emitting sound and receiving reflected sound. As is known in the art, the individual transducer elements are pulsed by an ultrasound control system, and the emitted sound waves are constructively combined into a primary beam. By varying the time each transducer element is pulsed, the ICE imaging system 300 can convert the individual beams into a focused image that can be swept in an arc to obtain a 2D image. As a result, the ultrasound transducer array 402 emits ultrasound waves along a plane perpendicular to the face of the transducer array. Thus, the ultrasonic transducer array 402 emits sound along a plane perpendicular to the assembly.

[0051] 10 , according to one embodiment of the present disclosure, the ICE catheter 304 may include a flexible sheath 1002 with marker bands 1004 that allow for location on an x-ray image 1006. The flexible sheath 1002 may have marker bands 1004 at a distal end 322 of the ICE catheter 304 to ensure passage into a patient's cardiac chamber, thereby allowing for location on the x-ray image 1006. It can be seen that the distal end 322 of the ICE catheter 304 can be coated with a material that provides electrical insulation and transmission of ultrasound signals generated by the ICE catheter 304. In one embodiment, the flexible sheath 1002 can be inserted into a cardiac chamber and its location can be identified on the x-ray image 1006 by the marker bands 1004. It can be seen that the image processor 308 of the ICE imaging device 302 can provide a real-time 2D image of the heart using the accepted locations on the x-ray image 1006. In one embodiment, flexible sheath 1002 corresponds to catheter shaft 336 and allows passage into the heart to provide localization on x-ray images 1006. In one embodiment, a patient suffering from CF may be treated with an ICE catheter 304 that has an electrically insulating coating to transmit ultrasound signals generated by the ICE catheter 304.

[0052] 11 , according to one embodiment of the present disclosure, the ICE catheter 304 can include an electrically insulated shaft 1102 at the distal end 322 of the ICE catheter 304. The electrically insulated shaft 1102 can use a copolymer material up to the imaging window 1104 at the distal end 322 of the ICE catheter 304. In one embodiment, the electrically insulated shaft 1102 can be coated with Pebax® material. The imaging window 1104 allows the ultrasound beam to travel to and from the ultrasound transducer array 402. In one embodiment, a steering handle 332 of the steering control unit 326 can be rotated clockwise and / or counterclockwise to obtain a front or rear view, thereby moving the imaging window 1104 from a rear view to a front view and / or vice versa. In another embodiment, the steering handle 332 can be steered in three-dimensional (3D) space. In another embodiment, the steering control unit 326 may be configured to rotate the distal tip 328 of the ICE catheter 304 left and / or right using the steering handle 322. Additionally, the distal tip 328 of the ICE catheter 304 is coated with an electrically insulating material to provide insulation and transmission of ultrasound signals.

[0053] 12 , electronic communication between the handle assembly 324 and the custom dongle 306 using a plurality of pogo pins 508, a board edge connector 606, or other connection means is disclosed, according to one embodiment of the present disclosure. The handle assembly 324 may be coupled to the interposer 406 using the board edge connector 606 and connector pins 608, which may be coupled to a plurality of in-line connection pads 614 of the PCB 610. In one embodiment, the interposer 406 may be referred to as a flat interposer. It will be appreciated that the interposer 406 may function as a bridge for transmitting at least one signal from the distal end 322 to the proximal end 320 along the longitudinal axis 318 of the ICE catheter 304. Furthermore, the interposer 406 may be connected to a plurality of electronic flex cables 1202 using a plurality of vias 612. In one embodiment, each of the plurality of electronic flex cables 1202 may have an individual connection. Furthermore, the plurality of electronic flex cables 1202 may be connected to the ultrasound transducer array 402.

[0054] In an alternative embodiment, the ICE catheter 304 may include a body (not shown) having a longitudinal axis 318 and a distal end 322. Further, the ultrasound transducer array 402 may be disposed within the distal end of the body. The ultrasound transducer array 402 may include a plurality of transducer array elements 802 disposed on a substrate 326. Further, the ultrasound transducer array 402 may be connected in series between at least one signal trace and a common ground. Further, each of the plurality of transducer array elements 802 may include a plurality of transducers, with a first transducer array element having a first group of two or more transducers and a second transducer array element having a second group of two or more transducers. Further, each of the plurality of transducer array elements 802 may be connected in parallel. Further, each transducer array element may include at least one piezoelectric layer disposed on the substrate 326. It will be appreciated that the at least one piezoelectric layer may include a pMUT array element. Additionally, each transducer array element may include at least one first electrode connected between the at least one piezoelectric layer and a signal conductor. Additionally, at least one second electrode may be connected between the at least one piezoelectric layer and a ground wire. In one embodiment, each pMUT array element may have a predetermined shape configured to accommodate a predetermined fundamental mode vibration.

[0055] In one embodiment, the ultrasound transducer array may include a plurality of piezoelectric micromachined ultrasound transducers (pMUTs) coupled to the distal end of the body. The pMUT array may be a linear phased array. In one embodiment, a first group of two or more transducers and a second group of two or more transducers may be connected in parallel. Furthermore, multiple transducer array elements of the plurality of transducer array elements may be grouped to function as a single array element.

[0056] Additionally, a method for deploying an intracardiac echocardiogram (ICE) catheter into a heart chamber through an internal venous system can be implemented. The ICE catheter includes an ultrasound transducer array 402 with a plurality of transducer array elements 802. The method includes directing the plurality of transducer array elements 802 to transmit and receive ultrasound beams to and from the heart via at least one signal trace; receiving at least one signal from the plurality of transducer array elements 802 based on the transmission and reception of at least one ultrasound beam of the plurality of ultrasound beams; and constructing at least one image of at least a portion of the heart chamber based on the at least one signal. In one embodiment, the ICE catheter is 2.0 mm (6 French) or smaller. In one embodiment, the venous system can be at least one of the jugular vein, the subclavian vein, the axillary vein, or the innominate vein.

[0057] Further disclosed is a method of deploying an ICE catheter having an ultrasound transducer array 402 with a plurality of transducer array elements 802 into a heart chamber using arterial access. The method includes directing the plurality of transducer array elements 802 to transmit and receive ultrasound beams to and from the heart via at least one signal trace; receiving at least one signal from the plurality of transducer array elements 802 based on the transmission and reception of at least one ultrasound beam of the plurality of ultrasound beams; and constructing at least one image of at least a portion of the heart chamber based on the at least one signal. In one embodiment, the venous system can be at least one of the femoral artery, the radial artery, or the brachial artery.

[0058] In another embodiment, a method is disclosed for visualizing lead location and facilitating lead / device delivery using a 2.0 mm (6 French) or smaller ICE catheter. The lead location is for a pacemaker or other implantable cardioverter defibrillator (ICD) lead. The method further includes using a 2.0 mm (6 French) or smaller ICE catheter to visualize the arterial system for device delivery, including, but not limited to, heart valve surgery, vascular surgery, and left heart surgery.

[0059] Referring to FIG. 13 , a cross-sectional image of a heart 1300 and a left subclavian vein 1302 is shown, with a pacemaker lead 1304 of a pacemaker 1306 positioned in the chest wall and multiple electronic flex cables 1202 introduced into the left subclavian vein 1302. The pacemaker lead 1304 is moved from the left subclavian vein 1302 toward another ventricle 1300. The pacemaker leads 1304 are positioned in different ventricles of the heart 1300 and stimulate muscles within the heart 1300. A pacemaker atrial lead 1308, a pacemaker right ventricular lead 1310, a left ventricle 1312, a right atrium 1314, a right ventricle 1316, and a pacemaker left ventricular lead 1318 can be visualized. For example, the pacemaker atrial lead 1308 is attached to the wall of the right atrium 1314. The pacemaker right ventricular lead 1310 is attached to the wall of the right ventricle 1316. A pacemaker left ventricular lead 1318 is attached to the wall of the left ventricle 1312. Additionally, the left atrium 1320, superior vena cava (SVC) 1322, interatrial septum (IAS) 1402, and tricuspid valve 1404 may also be visualized.

[0060] A pacemaker lead 1304 of a pacemaker 1306 may be inserted into the left subclavian vein 1302 via an entry point (not shown). The pacemaker lead 1304 is inserted into the left subclavian vein 1302 under or near the collarbone and navigated to the heart 1300 using x-ray imaging. One end of the pacemaker lead 1304 can be seen fixed in place within the heart 1300, and the other end can be seen attached to a pulse generator within the pacemaker 1306. The pulse generator and other pacemaker components are housed within a single capsule.

[0061] Referring to FIG. 14 , an ICE catheter 304 is shown positioned within the left subclavian vein 1302 of a heart 1300. The distal tip 328 of the ICE catheter 304 can be inserted into the right atrium 1314 via the left subclavian vein 1302 and the SVC 1322. Two standard views can be used to perform appropriate imaging of the IAS 1402 and its neighboring structures. Movement of the distal tip 328 of the ICE catheter 304 within the right atrium 1314 can be controlled by a steering control unit 326. Rotating a steering handle 332 of the steering control unit 326 can facilitate positioning of the distal tip 328 of the ICE catheter 304 within the patient's heart 1300. In one embodiment, manipulating the steering handle 332 clockwise can position the distal tip 328 of the ICE catheter 304 in a posterior view of the right atrium 1314. In another embodiment, the distal tip 328 of the ICE catheter 304 can be positioned in an anterior view of the right atrium 1314 by manipulating the steering handle 332 counterclockwise.

[0062] 14 , after being introduced into the patient's vasculature via the aforementioned venous structure, the ultrasound transducer array 402 can be advanced to a position for imaging the right atrium 1314. While monitoring the position of the ICE catheter 304 using ultrasound imaging, the clinician can advance the distal end 322 of the ICE catheter 304 into the right atrium 1314. To guide the ICE catheter 304 through the bends in the patient's vasculature, the clinician can rotate the steering handle 332 clockwise or counterclockwise or deflect the catheter tip in either direction to move the imaging window 1104 closer to or farther from the internal view. Once the distal tip 328 of the ICE catheter 304 is in the right atrium 1314, the clinician can turn the catheter by deflecting the steering handle 332 to guide the ultrasound transducer array 402 through the tricuspid valve 1404 and into the right ventricle 1316, as shown in FIG. 14 . In this position, the field of view of the ultrasound transducer array 402 includes a portion of the right ventricle 1316 and the RV lead tip interface to the ventricular myocardium, and the interventricular septum, left ventricle, and pericardial space can be visualized. When the transducer is pulled back into the left atrium 1320, the IAS 1402 can be visualized.

[0063] As an example, a standard view is obtained by placing the ICE catheter 304 in the right atrium 1314 and the ultrasound transducer array 402 in a neutral position facing the tricuspid valve 1404. The standard view provides images of the right atrium 1314, the tricuspid valve 1404, the right ventricle 1316, and typically also provides an oblique or short axis view of the aortic valve.

[0064] In one embodiment, the majority of catheters used in intravascular applications, particularly catheters equipped with ultrasound transducers, have a diameter of at least about 3.3 mm (about 10 French). The electronics and wires required for ultrasound transducer arrays make it impractical and expensive to reduce the size of such catheters below about 3.3 mm (about 10 French). Nevertheless, there are advantages to reducing the catheter diameter, and advances in technology may allow for further reductions in the size of the electronics and control structures. The bundled arrangement of the coaxial cables, steering and pivot cables, and steering and pivot mechanisms, described in more detail below, effectively allows for diameter reductions from less than about 10 French to 4, 6, or 8 French, or even 3 French (about 1 mm).

[0065] In one embodiment, to perform lead placement for cardiac implantable electrical devices, including but not limited to pacemakers, defibrillators, cardiac resynchronization therapy devices, and interventional and structural heart procedures, a 2.0 mm (6 French) or smaller ICE catheter can be introduced through the internal jugular / subclavian / axillary / innominate vein system to visualize lead position and facilitate lead / device delivery.

[0066] While particular structures embodying various embodiments of the invention have been shown and described herein, it will be apparent to those skilled in the art that various changes and rearrangements of parts may be made without departing from the spirit and scope of the underlying concept of the invention, and that the invention is not limited to the specific forms shown and described herein, except as indicated by the appended claims.

Claims

1. 1. An intracardiac echo (ICE) imaging system comprising: an ICE catheter having a longitudinal axis, a proximal end, and a distal end, the ICE catheter being 2.0 mm (6.0 French) or smaller to provide access to the heart and vasculature; an ultrasound transducer array disposed within the distal end of the ICE catheter, the ultrasound transducer array including a substrate and a plurality of transducer array elements disposed on the substrate; a catheter shaft connected at one end to a handle assembly and at the other end to the ultrasound transducer array, the catheter shaft housing an electronic flex cable in communication with at least one signal trace; the electronic flex cable comprising: directing each of the plurality of transducer array elements to transmit and receive a plurality of ultrasound beams to and from the heart via the at least one signal trace; receiving at least one signal from the plurality of transducer array elements based on transmission and reception of at least one ultrasound beam among the plurality of ultrasound beams; constructing at least one image of at least a portion of the heart based on the at least one signal; The ICE imaging system is configured as follows:

2. 10. The ICE imaging system of claim 1, wherein the ICE catheter is 2.0 mm (6.0 French) or less, thereby enabling co-deployment of the 2.0 mm (6.0 French) or less catheter with a pacemaker-defibrillator or implantable cardioverter-defibrillator (ICD) lead.

3. 3. The ICE imaging system of claim 2, wherein the ICE catheter is 2.0 mm (6.0 French) or less, thereby enabling confirmation of placement of a pacemaker defibrillator or other ICD lead.

4. The ICE imaging system of claim 1 , wherein the ultrasound transducer array corresponds to a microelectromechanical (MEMS)-based piezoelectric micromachined ultrasound transducer (pMUT).

5. 2. The ICE imaging system of claim 1, wherein the ICE catheter includes a steering control unit disposed within the handle assembly for articulating a distal tip of the ICE catheter and directing a face of the ultrasound transducer array to an internal view including an anterior or posterior position of the heart.

6. 6. The ICE imaging system of claim 5, wherein the distal tip of the ICE catheter is coated with a material that provides electrical insulation and transmission of ultrasound signals.

7. 6. The ICE imaging system of claim 5, wherein the steering control unit includes a steering handle and a housing that accommodates an actuator and a steering hub, and wherein internal friction occurs between the actuator and the steering hub and between the actuator and the housing, and this internal friction causes the ICE catheter to maintain an adjusted configuration without operator intervention.

8. 10. The ICE imaging system of claim 1, wherein the ICE catheter corresponds to a mechanical flexible sheath with marker bands to allow passage into the heart and to define a location on an X-ray image.

9. 10. The ICE imaging system of claim 1, wherein the ICE catheter is connected to an imaging device using a custom dongle, the custom dongle configured to communicate ultrasound transmit pulses and ultrasound receive waveforms between the imaging device and the ICE catheter.

10. 10. The ICE imaging system of claim 9, wherein the custom dongle includes an interposer having a plurality of pogo pins, a board edge connector, or other connection means attached to a flat circuit board of the handle assembly.

11. The ICE imaging system of claim 1 , wherein the catheter shaft houses a plurality of individual electronic flex cables connecting between the handle assembly and the ultrasound transducer array.

12. 2. The ICE imaging system of claim 1, wherein the ultrasound beam has a bandwidth that includes predetermined fundamental mode vibrations of each of the plurality of transducer array elements, such that a single array element simultaneously transmits and receives multiple fundamental mode vibrations.

13. The ICE imaging system of claim 1 , wherein each of the plurality of transducer array elements has transducer cells of multiple diameters to achieve a wide bandwidth.

Images