The invention generally relates to systems and methods that aid physicians in performing surgical procedures on patients. More specifically, the invention relates to systems and methods for non-invasively mapping the electrical activity of the heart and identifying sources of arrhythmia using electrodes on the patient's external body surface, projecting that information onto a computer imaged three-dimensional or four-dimensional model of the heart, and co-registering the model based on cardiac activity information with a position localization system which can be used to accurately navigate instruments during a procedure with respect to the sources of arrhythmia for treatment of the patient, and further augmenting the cardiac activity information with real-time intracardiac recordings from instruments navigated during the surgical procedure.
There exist very complex cardiac arrhythmias such as Atrial Fibrillation that are extremely hard to deconstruct to a source with conventional intracardiac catheters and traditional twelve-lead electrocardiogram readings. There are high resolution cardiac electrogram processing techniques that utilize large numbers of sampling electrodes spread all over a patient's thorax along with imaging techniques such as computerized tomography or magnetic resonance imaging to create models of the heart and project electrical activity at the body surface onto these imaging models. Ultimately, to make use of this high resolution body surface cardiac electrogram information for treating patients, the information must be presented in a manner in which the surgeon can process that information during a surgery, identify sources of the arrhythmia, translate that arrhythmia source information to anatomic information that they are able to manipulate and then deliver therapy to that source to treat the patient. Further, the electrical activity of the heart is constantly changing and measurements acquired from outside the body must be augmented with measurements acquired from inside the body to best highlight potential anatomic source regions of the arrhythmia. This must all be performed in a stable and consistent way, over heart beat and respiration cycles, so that the surgeon can trust the information before they deliver therapy to a particular region of the heart. Serious complications, such as sudden cardiac arrest, stroke, atrio-esophageal fistula and perforation can occur if therapy is delivered internally inaccurate based on the body surface cardiac electrical information.
Therefore, a practical need exists to have an accurate way of delivering body surface cardiac electrical information to a surgeon during a procedure in which they are manipulating instruments inside the body to diagnose the source of an arrhythmia and deliver therapy to that source.
Embodiments of the invention are summarized below. These and other embodiments are described in the Detailed Description. It is to be understood, however, that there is no intention to limit the invention to the forms described herein. One skilled in the art can recognize that there are numerous modifications, equivalents, and alternative constructions that fall within the spirit and scope of the invention as expressed in the claims.
In an embodiment, a rigid plate is configured to be placed on a patient. The rigid plate includes multiple unique imaging fiducials. A position sensor is configured to provide position information of the rigid plate. The rigid plate can be coupled to multiple body surface electrodes that can be placed on the thorax of the patient. The body surface electrodes can measure cardiac electrical activity of the patient. A control unit can receive an image scan of the patient as well as the cardiac electrical activity information from the body surface electrodes and position information of the rigid plate. The control unit can transform the cardiac electrical activity from the body surface electrodes into the coordinate system of the rigid plate.
In some embodiments, physicians can utilize multiple independent data components, each data component providing diagnostic clinical data about a patient. For example, a first data component can include an electrocardiogram (EKG) map that can identify an atrial tachycardia. A second data component can include an instrument position map that identifies the positions of instruments inside the heart based on a position sensing system that can aid the physician in manipulating instruments during an electrophysiology study. The electrocardiogram map can help localize the region within the atria identified as the source of ectopic activity driving a cardiac arrythmia. Catheters can be navigated, using the instrument position map, to that region of the heart. Further information can be gathered from that region of the atrium, such as, for example, local activation and voltage, to identify the specific ectopic pathologic source to treat.
As shown in
Referring again to
The multiple electrodes 105 within the electrode vest 115 can be made from any suitable conductive material, such as, for example, silver-chloride, platinum, copper, or gold. The electrode array can include any number of electrodes 105. As shown in
Also on the EKG electrode vest 115, as shown in
While shown in
The rigid plate 110 can include radiopaque fiducials (i.e., markers) 120, 125, 130, 135 such that the fiducials 120, 125, 130, 135 do appear in the final image taken by medical imaging equipment. Radiopaque fiducials 120, 125, 130, 135 can be any suitable material such that the fiducial 120, 125, 130, 135 will enhance in, for example, MRI, CT, or X-Ray imagery, such as, for example, steel or copper. In some embodiments, the fiducial 120, 125, 130, 135 can be soaked in a contrast medium such as, for example, gadolinium, such that it will enhance in MRI imaging. The rigid plate 110 and associated fiducials 120, 125, 130, 135 can be designed with a correct consistency of radiopacity to enhance in cone-beam-CT or other forms of intraprocedural X-Ray imaging. The radiopaque fiducials 120, 125, 130, 135 can be any suitable shape including, for example, circular, donut, triangular, square, and/or rectangular. The fiducials 120, 125, 130, 135 are also sometimes called imaging fiducials because they appear in imaging output.
In some embodiments, one or more fiducials 120, 125, 130, 135 can be electrodes and wiring used to collect body surface electrogram information (i.e., cardiac electrical activity information). In some embodiments, one or more fiducials 120, 125, 130, 135 can be position sensors to a position tracking system.
In some embodiments, the rigid plate 110 can be radiopaque and the fiducials 120, 125, 130, 135 can be a cutout in the rigid plate such that the rigid plate will appear in the final image taken by a medical imaging system. Such a configuration can allow the unique shape of the fiducial 120, 125, 130, 135 to appear in the image as contrasted with the rigid plate 110. Similarly stated, rather than a radiopaque fiducial 120, 125, 130, 135, the fiducial 120, 125, 130, 135 can be a void in the radiopaque rigid plate 110, which can still be visible in the final image from the medical imaging system (i.e., an imaging fiducial).
In some embodiments, the rigid plate 110 can include cut-outs for standard medical diagnostics placed on patients such as, for example, 12-Lead EKG pads.
Included on the rigid plate 110 can be multiple electromagnetic position sensors 140, 145. The multiple electromagnetic sensors 140, 145 can be any suitable electromagnetic sensor such as, for example, a copper coil winding or a gold coil winding. The electromagnetic sensors 140, 145 can be disposed on the rigid plate 110 orthogonally to one another, as shown in
The fiducials 120, 125, 130, 135 and electromagnetic sensors 140, 145 on the rigid plate 110 can be disposed such that each is a known distance between the other components. For example, as shown in
The multiple electrodes 105 within the EKG electrode vest 115 can be electrically coupled to the rigid plate 110. The rigid plate 110 can be disposed within the vest 115 (e.g., sewn in or embedded) such that it is located over a particular area of the patient, such as, for example, the patient's sternum, during the medical procedure, as shown in
In some embodiments, the rigid plate 110 can be multiple rigid plates 110. The multiple rigid plates 110 can be placed on multiple places on the patient's body. In some embodiments, each rigid plate 110 can be a unique shape and/or include a unique pattern. In embodiments using multiple rigid plates, each rigid plate 110 can include position sensors, such as, for example, electromagnetic sensors 140, 145. In other embodiments, only some rigid plates 110 include position sensors.
In some embodiments, the rigid plate 110 can include unique markings or the uniquely shaped plate, or the uniquely shaped fiducials 120, 125, 130, 135 can be used in realigning the electrodes 105 used to measure electrogram signals from the body surface after they have been removed. For example, each rigid plate 110 can include markings that enable a medical professional to precisely realign the rigid plate 110 on the patient's body (e.g., the sternum) if the rigid plate 110 is removed from the patient's body. For example, the markings in the rigid plate 110 can be a uniquely shaped cutout, which can allow the medical professional to mark that shape on the patient or the EKG electrode vest 115 before removing the rigid plate 110 from the patient. At a later time, the marking can be aligned with the cutout such that the rigid plate 110 is precisely relocated on the patient. Each rigid plate 110 can include a mechanism for removal and reattachment to the patient's body, such as, for example, a detachable base plate or a sticker that remains affixed to the patient while the rigid plate 110 is removed. Such a removal and reattachment mechanism can aid in re-aligning the rigid plate 110 on the patient at a later time.
Using the multiple electrodes 105, surface electrograms (EKGs) can be measured. The patient can also be imaged with the multiple electrodes 105 using, for example, Computed Tomography (CT). Using that image data, a model of the heart can be constructed. The cardiac electrogram data that is being measured using the multiple electrodes can be projected onto that model of the heart, as disclosed by U.S. Pat. No. 7,983,743 to Rudy, et al, which is incorporated by reference herein in its entirety. Similarly, 12-Lead EKG information can be projected onto a model of the heart as seen in
In some embodiments including multiple rigid plates 110 and/or fiducials 120, 125, 130, 135 that are uniquely shaped, specific fiducials 120, 125, 130, 135 can be segmented out of imagery easily. Specifically shaped fiducials 120, 125, 130, 135 can also aid in correlating the orientation of the fiducials 120, 125, 130, 135 in relation to unique sensors that can be placed on the body. As seen in
In some embodiments, the rigid plate 110 can be electrically coupled to one or more electrodes 105. In such embodiments, the electrodes 105 can drive current through the patient's body to serve as a the basis for a position locating system of instruments within the body as disclosed in U.S. Pat. No. 5,983,126 to Wittkampf, et al., which is incorporated herein by reference in its entirety.
In use, the patient can be image scanned (e.g., CT scanned) with the multiple electrodes 105 and the rigid plates 110 applied to the patient. The scan can be displayed on a computer monitor 155, such as, for example, as shown in
Software instructions running on a computer that is a part of a position location system can be programmed to receive that image scan data and automatically identify and segment out the unique fiducials 120, 125, 130, 135 associated with respect to the rigid plate 110. Software instructions can be programmed to search for the unique shapes of the fiducials 120, 125, 130, 135 and their geometric orientation in order to determine the location and correlation of position sensors 140, 145 associated with the rigid plate 110 in the coordinate system of the image data (i.e., sensor #1 in position #1 in an image coordinate system and sensor #2 in position #2 in the image coordinate system).
A position tracking system, such as the one disclosed in U.S. patent application Ser. No. 13/747,266 to Edwards, et al., can be applied to the patient. As shown in
During use, the patient's heart can shift internally with respect to the external body surface rigid plate 110. In such instances, the second transformation matrix can be updated and applied to electrogram data such that it will be projected onto images of the heart accurately. Accuracy can be maintained during minor and major internal changes, such as, for example, if the patient's left lung hyper-inflates during a procedure due to a complication associated with tracheal intubation. As another example, accuracy can be maintained if, for example, the patient's heart shifts with respect to the external electrodes or fiducials.
Body surface electrogram information can be automatically registered to a consistent position tracking system and its associated internal reference instrument. The position of other instruments tracked by the tracking system can be displayed in the same consistent tracking system, such as, for example, as depicted in
As shown in
During the course of the procedure, medical instruments such as, for example, a roving ablation catheter, a multi-electrode loop, a multi-electrode star, and/or a multi-electrode basket can be tracked by the position tracking system. The medical instrument can be for example, internal reference instrument 160 of
a and 3b are models of a heart showing conduction velocity 320 and potential rotor locations 330. The conduction velocity 320 is information that can be obtained by, for example, internal reference instrument 160 (
c is similarly a model of a heart showing voltage information. The voltage information can be collected by, for example, internal reference instrument 160 (
The medical instrument, such as internal reference instrument 160 (
The combination of co-registered external and internal based cardiac information can be used in planning therapeutic procedures and augmenting those plans during surgery. Specifically, external body surface electrogram information can be used to identify, annotate, and plan the vicinity of a target location for therapy delivery on a heart image model. During the procedure, various information data such as voltage transitions can be obtained from an internal instrument tracked with respect to the internal reference instrument and co-registered to the external body-surface electrogram information to augment initial treatment plans.
Therapy can be provided by an internal instrument, for example, a roving ablation catheter. In some embodiments, there are multiple internal instruments. For example, the system can include body surface electrodes to collect cardiac electrical activity of the patient from the body surface of the patient as described above. As also described above, an internal reference instrument can be used to collect cardiac electrical activity of the patient from, for example, the coronary sinus. In this way, both internal measurements and external measurements can be collected and used to provide images of the heart that map or show the location of instruments in relation to each other and their location within the patient's body. Further, there can be an internal roving instrument, such as a roving ablation catheter, that can be introduced into the patient's body. The internal roving instrument can include a position sensor to provide the position information to the processor. The processor can convert the position information of the internal roving instrument into any of the coordinate systems already in use such that the location of the internal roving instrument can also be presented with the information of the other instrument information on the model of the heart on the display being used by the surgeon. The surgeon can utilize the information to provide therapy to the patient. For example, a roving ablation catheter can be used to ablate tissue in the patient's heart that may be causing atrial fibrillation. In some embodiments, the internal roving instrument can be configured to provide therapy that creates non-conductive scar tissue.
In some embodiments, for example, body surface electrogram information on a heart model may be used to identify the optimal site to place a pacemaker or defibrillator lead or an entirely miniaturized pacemaker or defibrillator to ensure optimal current flow from the stimulation source through diseased or scarred tissue to stimulate the heart in a manner that resonates with sinus rhythm as opposed to introducing current flow patterns that may cause another unwanted arrhythmia. During the surgery, additional measurements may be taken from a tracked internal instrument to further understand patient characteristics internally, such as voltage transitions indicating scar tissue, and that information can be merged with the original model of the heart and the associated body surface electrogram information. This combined information can be used to tune the output settings of a pacemaker or defibrillator based on external and internal information of the patient. Similar methods of treatment delivery can be constructed for biological drug delivery such as nano-particles, stem-cells, gene therapy.
Once the model of the heart is constructed, an ultrasound probe with its own position sensor capable of being tracked by the position tracking system can be used to create a second model of the heart in the same co-registered coordinate system originating from the body surface electrogram data. The first model of the heart and all associated information can be linearly or non-linearly deformed to mold to the secondary model of the heart. A sound measuring device or set of devices with integrated position sensors can be affixed to the patient's body surface. The speed of sound measurements reaching the external sound measuring devices from a tracked internal ultrasound transducer can be used to augment initial body surface electrogram calculations and associated projections onto a heart model.
Once the data is integrated and co-registered into the coordinate system of the internal reference instrument and its position tracking system, a tracked catheter with one or more magnetic elements may be positioned with the use of high field magnets in order to position that catheter to a target location defined by the co-registered information beginning with the body surface electrogram information.
Once the data is integrated and co-registered into the coordinate system of the internal reference instrument and its position tracking system, a tracked catheter, shrouded by a robotic sheath, may be positioned with the use of robotic sheath manipulator in order to position that catheter to a target location defined by the co-registered information beginning with the body surface electrogram information.
Once the data is integrated and co-registered into the coordinate system of the internal reference and its position tracking system, an external radiation beam source may be positioned with the use of a robotic manipulator in order to position the beam to a target location defined by the co-registered information beginning with the body surface electrogram information.
It is intended that the systems and methods described herein can be performed by software (stored in memory and/or executed on hardware), hardware, or a combination thereof. Hardware modules may include, for example, a general-purpose processor, a field programmable gate array (FPGA), and/or an application specific integrated circuit (ASIC). Software modules (executed on hardware) can be expressed in a variety of software languages (e.g., computer code), including Unix utilities, C, C++, Java™, Ruby, SQL, SAS®, the R programming language/software environment, Visual Basic™, and other object-oriented, procedural, or other programming language and development tools. Examples of computer code include, but are not limited to, micro-code or micro-instructions, machine instructions, such as produced by a compiler, code used to produce a web service, and files containing higher-level instructions that are executed by a computer using an interpreter. Additional examples of computer code include, but are not limited to, control signals, encrypted code, and compressed code. Each of the devices described herein can include one or more processors as described above.
Some embodiments described herein relate to devices with a non-transitory computer-readable medium (also can be referred to as a non-transitory processor-readable medium or memory) having instructions or computer code thereon for performing various computer-implemented operations. The computer-readable medium (or processor-readable medium) is non-transitory in the sense that it does not include transitory propagating signals per se (e.g., a propagating electromagnetic wave carrying information on a transmission medium such as space or a cable). The media and computer code (also can be referred to as code) may be those designed and constructed for the specific purpose or purposes. Examples of non-transitory computer-readable media include, but are not limited to: magnetic storage media such as hard disks, floppy disks, and magnetic tape; optical storage media such as Compact Disc/Digital Video Discs (CD/DVDs), Compact Disc-Read Only Memories (CD-ROMs), and holographic devices; magneto-optical storage media such as optical disks; carrier wave signal processing modules; and hardware devices that are specially configured to store and execute program code, such as Application-Specific Integrated Circuits (ASICs), Programmable Logic Devices (PLDs), Read-Only Memory (ROM) and Random-Access Memory (RAM) devices. Other embodiments described herein relate to a computer program product, which can include, for example, the instructions and/or computer code discussed herein.
While various embodiments have been described above, it should be understood that they have been presented by way of example only, and not limitation. Where methods and/or schematics described above indicate certain events and/or flow patterns occurring in certain order, the ordering of certain events and/or flow patterns may be modified. While the embodiments have been particularly shown and described, it will be understood that various changes in form and details may be made.
Although various embodiments have been described as having particular features and/or combinations of components, other embodiments are possible having a combination of any features and/or components from any of embodiments as discussed above.
This application is a continuation of International Application No. PCT/US2015/021435, filed Mar. 19, 2015, which claims priority to U.S. Provisional Patent Application No. 61/955,673, entitled “System and Methods for Integrating Cardiac Electrical Maps and Intraprocedural Information,” filed on Mar. 19, 2014, each of which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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61955673 | Mar 2014 | US |
Number | Date | Country | |
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Parent | PCT/US15/21435 | Mar 2015 | US |
Child | 14802641 | US |