Patent Application
20200383599
The present invention relates to the field of medical devices. More specifically, the present invention is directed to determining and representing anatomical and physiological information related to a heart using a contact catheter.
The human heart routinely experiences electrical impulses traversing its many surfaces and ventricles, including the left atrium. Just prior to each heart contraction, the heart depolarizes and repolarizes as electrical currents spread across the heart and throughout the body. In healthy hearts, the surfaces and ventricles of the heart experience an orderly progression of depolarization waves. In unhealthy hearts, such as those experiencing atrial arrhythmia, including for example, ectopic atrial tachycardia, atrial fibrillation, and atrial flutter, the progression of the depolarization wave becomes chaotic. Arrhythmias may persist because of scar tissue or other obstacles to rapid and uniform depolarization. These obstacles may cause depolarization waves to electrically circulate through some parts of the heart more than once. Atrial arrhythmia can create a variety of dangerous conditions, including irregular heart rates, loss of synchronous atrioventricular contractions, and blood flow stasis. These conditions are associated with a variety of ailments, including death.
Catheters are used in a variety of diagnostic and therapeutic medical procedures to diagnose and correct conditions such as atrial arrhythmia, including for example, ectopic atrial tachycardia, atrial fibrillation, and atrial flutter. Typically, in such a procedure, a catheter carrying one or more electrodes is moved through a patient's vasculature to the heart under fluoroscopy-guided observation. The electrodes may be used for mapping, ablation, diagnosis, or other treatments.
When an ablation therapy is desired to alleviate symptoms including atrial arrhythmia, the ablation catheter imparts ablative energy to cardiac tissue to create a lesion in the cardiac tissue. The lesioned tissue is less capable of conducting electrical signals, thereby disrupting undesirable electrical pathways and limiting or preventing stray electrical signals that lead to arrhythmias. The ablation catheter may utilize ablative energy including, for example, radio-frequency (RF), cryoablation, laser, chemical, and high-intensity focused ultrasound.
However, before a physician can perform an ablation therapy, the anatomical structure and physiological health of the heart must first be obtained. This is typically done using a contact catheter. In contact mapping, a catheter is advanced into the heart and, after determining that a distal electrode-carrying spline section of the catheter is in stable and steady contact with the endocardium surface of a heart chamber of interest, physiological signals resulting from electrical activity of the heart are acquired from one or more electrodes supported on the splines. Electrical activity is usually measured sequentially on a point-by-point basis at about 50 to 200 locations on the endocardium surface of the heart to construct an electro-anatomical depiction of the heart. The generated map then serves as the basis for deciding on a therapeutic course of action, for example, tissue ablation, to alter the propagation of the heart's electrical activity and to restore normal heart rhythm.
While conventional basket-type EP (electro-physiology) catheters have many electrodes, for example eight electrodes on eight splines for a total of 64 electrodes or 16 electrodes on eight splines for a total of 128 electrodes, to sufficiently map the anatomical structure of the heart, they require a separate voltage-out (Vout) conductor for each electrode. The Vout conductors bring the electrode sample signal down the catheter to the proximal connector detachably connected to a controller for signal analysis. Not only is having a dedicated Vout conductor for each electrode in a spline system complicated and difficult to construct, it does not much leave room in the catheter shaft for other structure, such as a delivery lumen, a suction lumen, a fiber optic cable, pull wires, and the like.
Therefore, there is a need for an improved basket-type EP catheter that is useful for mapping the anatomical structure and physiological health of the heart prior to a physician performing a diagnostic or therapeutic medical procedure. The improved basket-type EP catheter of the present invention satisfies this need by providing one Vout conductor system connecting from the proximal end of the catheter to the distal basket-shaped electrode-carrying spline system. Only one Vout conductor is needed because the individual electrodes of the spline system are sampled sequentially by using a “one-shot” circuit and a signal pass-transistor or transmission gate at each electrode. The use of one Vout conductor provides ample space for other structure that is desirable in catheters, such as the previously described delivery lumen, suction lumen, fiber optic cable, pull wires, and the like. In the alternative, since only one Vout conductor connects from the proximal end of the catheter to the distal basket-shaped electrode-carrying spline system, the EP catheter of the present invention has a smaller diameter or French size than conventional EP catheters. This means the basket-type EP catheter of the present invention is less obstructive than conventional mapping catheters as it is navigated through the patient's vasculature to the heart.
By sampling the voltage signal on each of a plurality of electrodes sequentially or consecutively, only one Vout conductor system is needed to transmit the voltage sample from each electrode to the proximal connector and then to the controller. This greatly reduces the number of conductors extending along the catheter shaft, which means there is ample room for other structure or lumens that may be useful to a physician during a mapping procedure. The use of a single Vout conductor system is implemented by connecting a “one-shot” circuit and a signal pass-transistor or transmission gate to each electrode. For example, if there are 128 electrodes spaced along four splines, a sample frequency of 128 KHz is sufficient to sample every electrode every millisecond. Consequently, the use of a single Vout conductor system to sequentially sample the voltage signal from each of a plurality of electrodes is an advancement over known basket-type EP catheters.
Thus, one embodiment of the present EP catheter comprises A catheter system, comprising a controller, a catheter extending from a catheter proximal end to a catheter distal end. The catheter comprises a catheter proximal connector at the catheter proximal end, the catheter proximal connector being electrically connectable to the controller, a catheter distal connector supported at the catheter distal end, and an electrical cable comprising a catheter clock/trigger (Clk/Trig) conductor, a catheter ground (Gnd) conductor, a catheter voltage-source (Vsource) conductor, and a catheter voltage-out (Vout) conductor. The electrical cable extends along the catheter to the catheter proximal and distal catheter connectors. At least a first spline extends from a spline proximal anchor electrically connected to the electrical cable at the catheter distal connector to a spline distal anchor. At least three electrodes are supported by the first spline, the three electrodes comprising a first spline first electrode located closest to the spline proximal anchor, a first spline second electrode, and a first spline third electrode located furthest from the spline proximal anchor. Then, with the catheter proximal connector electrically connected to the controller through the electrical cable, the controller is configured to initiate a first consecutive electrode sampling sequence along the first spline by sending a clock/trigger (Clk/Trig) signal along the catheter Clk/Trig conductor to a first Clk/Trig conductor connected to a first spline first polling circuit configured to activate the first spline first electrode and then pass a first spline first electrode voltage sample to the catheter Vout conductor electrically connected to the controller. After the first spline first electrode voltage sample has been sent to the controller, the first spline first polling circuit is configured to send a Clk/Trig signal along a second Clk/Trig conductor connected to a first spline second polling circuit configured to activate the first spline second electrode and then pass a first spline second electrode voltage sample to the catheter Vout conductor electrically connected to the controller. And, after the first spline second electrode voltage sample has been sent to the controller, the first spline second polling circuit is configured to send a Clk/Trig signal along a third Clk/Trig conductor connected to a first spline third polling circuit configured to activate the first spline third electrode and then pass a first spline third electrode voltage sample to the catheter Vout conductor electrically connected to the controller. Then, after the first spline third electrode voltage sample has been sent to the controller, the controller is configured to initiate a second consecutive electrode sampling sequence.
Another embodiment of the present EP catheter comprises a controller, a catheter extending from a catheter proximal end to a catheter distal end. The catheter comprises a catheter proximal connector at the catheter proximal end, the catheter proximal connector being electrically connectable to the controller, a catheter distal connector supported at the catheter distal end, and an electrical cable comprising a clock/trigger (Clk/Trig) conductor, a ground (Gnd) conductor, a voltage-source (Vsource) conductor, and a voltage-out (Vout) conductor, wherein the electrical cable extends along the catheter to the catheter proximal and distal catheter connectors. At least a first spline extends from a spline proximal anchor electrically connected to the electrical cable at the catheter distal connector to a spline distal anchor. At least three electrodes are supported by the first spline, the three electrodes comprising a first spline first electrode, a first spline second electrode, and a first spline third electrode. Then, with the catheter proximal connector electrically connected to the controller through the electrical cable, the controller is configured to initiate a first consecutive electrode sampling sequence along the first spline by sending a clock/trigger (Clk/Trig) signal along the catheter Clk/Trig conductor to a first Clk/Trig conductor connected to a first spline first polling circuit configured to activate the first spline first electrode and then pass a first spline first electrode voltage sample to the catheter Vout conductor electrically connected to the controller. After the first spline first electrode voltage sample has been sent to the controller, the first spline first polling circuit is configured to send a Clk/Trig signal along a second Clk/Trig conductor connected to a first spline second polling circuit configured to activate the first spline second electrode and then pass a first spline second electrode voltage sample along the catheter Vout to the controller. And, after the first spline second electrode voltage sample has been sent to the controller, the first spline second polling circuit is configured to send a Clk/Trig signal along third Clk/Trig conductor connected to a first spline third polling circuit configured to activate the first spline third electrode and then pass a first spline third electrode voltage sample along the catheter Vout conductor to the controller. Then, after the first spline third electrode voltage sample has been sent to the controller, the controller is configured to initiate a second consecutive electrode sampling sequence.
These and other aspects of the present invention will become increasingly more apparent to those skilled in the art by reference to the following detailed description and to the appended drawings.
As used herein, the terms “sampling sequence”, “consecutive electrode sampling sequence” and “consecutively sampling” mean that the electrodes on a spline or a number of splines forming a spline system are sampled in a consecutive manner with a second or next electrode being sampled following sampling of a first electrode or an electrode located immediately before the second electrode without interruption.
Commercially available basket-type EP catheters have many electrodes. For example, there are basket-type EP catheters that have eight electrodes on eight splines for a total of 64 electrodes or 16 electrodes on eight splines for a total of 128 electrodes. Conventional systems require a separate voltage-out (Vout) conductor for each electrode. The dedicated Vout conductor passes voltage from an electrode to signal analysis hardware connected to the proximal end of the catheter. This means that there is a separate Vout conductor connected to each electrode of a spline and each spline Vout conductor is in turn connected to a respective catheter Vout conductor extending to a proximal connector that is connected to the signal analysis hardware, for example a controller.
According to the present invention, elimination of separate Vout conductors for each electrode supported by a spline is implemented by connecting a “one-shot circuit” and a signal pass-transistor or transmission gate to each electrode in a spline so that electrical signals are transmitted consecutively one-by-one from a plurality of electrodes along a single Vout conductor system to the proximal connector 14. For example, in a spline system having 128 electrodes, by using a sample frequency of 128 KHz, each electrode of the plurality of electrodes is sampled every millisecond, which is sufficient to track the signal of each electrode along a single Vout conductor.
In that manner, the present invention greatly reduces the number of electrical conductors that are needed for a spline system having many electrodes, for example the exemplary 64 or 128 electrode systems discussed above. By sampling the electrical signal from each electrode consecutively, only one Vout conductor is required in the catheter and in each of a plurality of splines comprising a spline system. As will be described in greater detail hereinafter, the catheter comprises a clock/trigger (Clk/Trig) conductor, a ground (Gnd) conductor, a voltage-source (Vsource) conductor and a voltage-out (Vout) conductor. There are corresponding Clk/Trig, Gnd, Vsource and Vout conductors in each spline. The catheter Vout conductor and the Vout conductors in each spline make up the so-called “Vout conductor system”. It is the Clk/Trig conductor that is connected to the “one-shot circuit” and the signal pass-transistor or transmission gate.
Turning now to the drawings,
An exemplary catheter 12 is a tubular member that extends from the proximal connector 14 at the catheter proximal end 12A to the distal connector 20 at the catheter distal end 12B. The tubular catheter 12 is formed of a polymeric material, such as of PEBAX, encasing a tubular wire braided as a mesh. A liner of a second polymeric material, for example PTFE, resides inside the PEBAX tube. In some embodiments, the catheter 12 has a delivery lumen (not shown) and the PTFE liner provides the delivery lumen with sufficient lubricity so that medical instruments, devices, and the like, slide through the lumen with a minimal amount of force. The delivery lumen is sized and shaped to receive, for example, instruments, fluids, media, and the like.
The controller cable 18 connecting between the controller 16 and the catheter 12 has a clock/trigger (Clk/Trig) conductor 86 that is detachably connected to a Clk/Trig conductor 88 in the catheter cable 84 that in turn is detachably connected to a Clk/Trig conductor 74 running through the spline system 24. There is also a controller ground (Gnd) conductor 90 connected to a catheter ground conductor 92 in turn connected to a ground conductor 76 in the spline system. A voltage-source (Vsource) conductor 94 in the controller 16 connects to a Vsource conductor 96 in the catheter 12 and onto a Vsource conductor 78 in the spline system 24. Finally, a voltage-output (Vout) conductor 98 connects from a signal conditioning circuit 100 in the controller 16 to a Vout conductor 102 in the catheter 12 and then onto a Vout conductor 80 in the spline system 24. The signal conditioner circuit 100 is electrically connected to the microprocessor 82 of the controller 16.
The Gnd conductor 76, the Vsource conductor 78 and the Vout conductor 80 in the spline system are sequentially connected to a dedicated polling circuit associated with each of the plurality of electrodes. In a sampling sequence, the controller 16 sends a sampling trigger signal (Clk/Trig) to a 1st electrode 104 in the first spline 28 of the spline system. In the previously described sampling sequence for the exemplary four-spline system described with respect to
After the first voltage sample from the 1st electrode 104 is sent to the controller 16, the 1st electrode polling circuit 106 sends a clock/trigger signal to a 2nd electrode 108 to activate the associated polling circuit 110. The 2nd electrode 108 is the previously described next most proximal electrode on spline 28. Activation of the 2nd polling circuit 110 causes a second unipolar EGM voltage sample to be sent from the 2nd electrode 108 to the controller 16 along the Vout conductor 80. This sequencing continues until the previously described proximal-most electrode 112 on the fourth spline 34 is activated by an associated polling circuit 114 (indicated as the nth electrode and nth polling circuit in
Among other useful information, the controller 16 is programmed to calculate the values of voltage versus time of the cardiac electrical activity at each electrode. This information can be plotted in a 2D or 3D graph or matched to 3D images of the heart to give a time varying 3D plot of electrical activity in the heart. The controller is configured to display or present this information in real-time in any one of a variety of formats that are useful to a physician.
The structure for consecutively sampling the electrical signal from each of a plurality of electrodes in a spline system so that only one Vout conductor is required as illustrated in
Referring now to
Referring now to
Thus, the trigger electrical conductor 88 in the catheter cable 84 connects only to terminal block 66. As will be described in detail later in
Another embodiment of the present invention related to a unipolar EGM is shown in
For the 1st electrode 104, the trigger signal on conductor 74 is connected to the trigger input of the monostable multivibrator 116. The output of the monostable multivibrator 116 is connected to the gate of the N-Channel Enhancement-MOSFET 118 and to an inter-sensor trigger signal conductor 74A which in turn is connected to the trigger input of a 2nd monostable multivibrator 120 of the next electrode/sensor station circuit.
The electrode 104 is connected to the drain terminal of the N-Channel Enhancement-MOSFET 118 which passes an EGM sample signal to the voltage-out conductor 80 via the source terminal when the MOSFET 118 is ON. Every subsequent electrode to the nth electrode 112 is connected in the same way, but instead of the trigger voltage coming from the controller 16, the trigger voltage enters the nth monostable vibrator 124 connected to the output from the monostable vibrator of the previous electrode along an inter-trigger signal conductor 74B.
Both electrodes of the pair 104A and 104B are electrically connected to an electric circuit consisting of a monostable multivibrator 116 and two N-Channel Enhancement-MOSFET pass transistors 118A and 118B, one MOSFET for each electrode. The gates of the MOSFETs are connected and are also connected to the output of the first monostable multivibrator 116 so that both MOSFETs switch ON or OFF simultaneously when the output from the monostable multivibrator 116 is high or low, respectively. The output of the monostable multivibrator is also connected directly to the trigger input of the monostable multivibrator of the next circuit via the inter-sensor trigger signal conductor 74A.
When the monostable multivibrator 116 is triggered, the one-shot circuit outputs an electrical pulse of a pre-defined duration to the gates of the N-Channel Enhancement-MOSFETs 118A and 118B associated with the pair of electrodes 104A and 104B and to the monostable vibrator 120 of the next circuit before returning to its stable state.
When the output from the monostable multivibrator is high, the gates of both MOSFETs go high thereby switching the MOSFETs ON so that the voltage on electrode 104A is passed via the drain and source of the first MOSFET 118A to conductor 80A and simultaneously the voltage on electrode 104B is passed via the drain and source of the second MOSFET 118B to conductor 80B. The monostable multivibrator 120 of the next circuit is not triggered until the falling edge of the electrical pulse output from the monostable multivibrator 116 arrives at the trigger input of the monostable multivibrator 120 at the end of the pulse. As will be seen below, this ensures that voltages from electrodes 108A and 108B are not being passed onto conductors 80A and BOB, respectively, at the same time as voltages from electrodes 104A and 104B are being passed onto the conductors 80A and BOB, respectively.
Continuing, for the 2nd pair of electrodes 108A and 108B, which are also electrically connected to an electric circuit consisting of a monostable multivibrator 120 and two N-Channel Enhancement-MOSFET pass transistors 122A and 122B, one MOSFET is provided for each electrode. The gates of the MOSFETs 122A and 122B are connected and are also connected to the output of the second monostable multivibrator 120 so that both MOSFETs 122A, 122B switch ON or OFF simultaneously when the output from the monostable multivibrator 120 is high or low, respectively. The output of the monostable multivibrator is also connected directly to the trigger input of the monostable multivibrator of the next circuit via the inter-sensor trigger signal conductor 74B.
When the monostable multivibrator 120 is triggered by the falling edge of the output electrical pulse of monostable multivibrator 116, it outputs an electrical pulse of a pre-defined duration to the gates of the N-Channel Enhancement-MOSFETs 122A and 122B associated with the pair of electrodes 108A and 108B and to the monostable multivibrator of the next circuit before returning to its stable state. When the output from the monostable multivibrator is high, then the gates of both MOSFETs 122A and 122B go high thereby switching the MOSFETs ON so that the voltage on electrode 108A is passed, via the drain and source of the MOSFET 122A, to conductor 80A and simultaneously the voltage on electrode 108B is passed, via the drain and source of the MOSFET 122B, to conductor 80B. The monostable multivibrator of the next circuit is not triggered until the falling edge of the electrical pulse output from the monostable multivibrator 120 arrives at the trigger input of the next monostable multivibrator at the end of the output pulse from monostable multivibrator 120.
The output of the monostable multivibrator 120 is connected to the next circuit via the inter-sensor trigger signal conductor 74B which is connected to the trigger input of the monostable multivibrator 124 connected to the next or nth electrode 112A. This sequencing continues until each electrode of all the pairs of electrodes has been sampled. Upon completion of a full sampling sequence, the controller 16 initiates another sampling sequence beginning with the first pair of electrodes 104A/104B.
As shown in
Ideally the A/D converter 128 is positioned as close as possible to the electrodes in the spline system 24. The optimum construction is to position the A/D converter in the electrode circuit. This is shown in
The next optimum construction is to position the A/D converter at the distal end 12B of the catheter 12 as previously shown in
Having a fundamental understanding of a sampling sequence according to the present invention, one can see that
Sequencing on the second spline 30 begins with the nth polling circuit 162 on the first spline 28 sending a clock/trigger signal inter-trigger signal along conductor 74C to the distal connector 26 and then to conductor 74D connected to the let polling circuit 166 to activate the 1st electrode 164 on the second spline 30. After sending an EGM sample to the controller 16, the 1st polling circuit 166 sends a clock/trigger signal along inter-trigger signal conductor 74E to the 2nd polling circuit 170 to activate the 2nd electrode 168 on the second spline 30. This causes an EGM sample to be sent from the 2nd polling circuit 170 to the controller 16 for processing. This sequencing continues along spline 30 until the proximal-most or nth electrode 172 on that spline 30 is activated by its associated polling circuit 174 triggered by a trigger signal along inter-trigger signal conductor 74F from the previous most adjacent polling circuit and an EGM voltage sample is sent to the controller 16.
Sequencing on the third spline 32 begins with the nth polling circuit 174 on the second spline 30 sending a clock/trigger signal along inter-trigger signal conductor 74G to the proximal connector 22 and then to conductor 74H connected to the 1st polling circuit 178 to activate the 1st electrode 176 on the third spline 32. After sending an EGM sample to the controller 16, the 1st polling circuit 178 sends a clock/trigger signal along inter-trigger signal conductor 74I to the 2nd polling circuit 182 to activate the 2nd electrode 180 on the third spline 32. This causes an EGM sample to be sent from the 2nd polling station 182 on the third spline 32 to the controller 16 for processing. This sequencing continues along spline 32 until the proximal-most or nth electrode 184 on that spline 32 is activated by its associated polling circuit 186 triggered by a trigger signal along inter-trigger signal conductor 74J from the previous most adjacent polling circuit and an EGM voltage sample is sent to the controller 16.
Sequencing on the fourth spline 34 begins with the nth polling circuit 186 on the third spline 32 sending a clock/trigger signal along inter-trigger signal conductor 74K to the distal connector 26 and then to conductor 74L connected to the 1st polling circuit 190 to activate the electrode 188 on the fourth spline 34. The 1st polling circuit 190 then sends a clock/trigger signal to the 2nd polling circuit 194 along inter-trigger signal conductor 74M to activate the 2nd electrode 192 on the fourth spline 34. This causes an EGM sample to be sent from the 2nd electrode 192 to the controller 16 for processing. This sequencing continues along spline 34 until the previously described proximal-most electrode 112 on the fourth spline 34 is activated by its associated polling circuit 114 triggered by a trigger signal along inter-trigger signal conductor 74N from the previous most adjacent polling circuit and an EGM voltage sample is sent to the controller 16.
This completes one full sampling sequence for the four-spline system illustrated in
Referring now to
As previously described, in a sampling sequence the controller 16 sends a sampling trigger signal (Clk/Trig) along the catheter cable 84 and along conductor 74 to initiate signal activation of the polling circuit 106 for the 1st electrode 104A. The polling circuit 106 then passes the first EGM voltage sample from the electrode 104A to the controller 16 along the Vout conductor 80. The 1st polling circuit 106 then sends a clock/trigger signal to the 2nd electrode 108A along conductor 74A to activate its polling circuit 110. A second unipolar EGM voltage sample is then sent from the 2nd electrode 108A to the controller 16 along Vout conductor 80. This sequencing continues until the previously described nt electrode and nth polling circuit in
A via hole 304 extending through the thickness of the flexible substrate for the flex circuit 300 provides a conductive pathway to a flexible plate-shaped electrode 104B supported on the opposite side of land for the flex circuit. The flexible electrode 104B is then wrapped around the cylindrically-shaped insulator 306 shown in
While not shown in the drawings, the proximal end 12A of the catheter 12 for the basket-type EP catheter system 10 of the present invention is configured to connect to a handle assembly. In one embodiment, the handle assembly houses a steering and locking mechanism that provides for selective deflection or steering of the catheter 12 and the detachable spline system 24 into any number of disparate orientations within the vasculature of a patient and then for locking the catheter in a desired orientation for performing a medical procedure. For a more thorough understanding of catheter handles that are useful with the present basket-type EP catheter system 10, reference is made to U.S. Design Pat. Nos. D612,044 to Scheibe, D638,934 to Kimmel, D653,335 to Kampa et al. and D653,337 to Kampa et al., all of which are assigned to the assignee of the present invention and incorporated herein by reference.
For a more thorough understanding of deflectable catheter steering and locking systems that are useful with the present basket-type EP catheter system 10, reference is made to U.S. Pat. No. 7,497,853 to Fischer et al., U.S. Pat. No. 7,588,555 to Pudelko et al., U.S. Pat. No. 7,615,044 to Scheibe et al., U.S. Pat. No. 7,955,314 to Fischer et al., U.S. Pat. No. 8,007,463 to Pudelko et al., U.S. Pat. No. 8,048,026 to Fischer et al., U.S. Pat. No. 8,308,659 to Scheibe et al., U.S. Pat. No. 8,444,626 to Fischer et al., U.S. Pat. No. 8,790,362 to Kimmel et al. and U.S. Pat. No. 9,149,607 to Scheibe et al., all of which are assigned to the assignee of the present invention and incorporated herein by reference.
For a more thorough understanding of push-pull wire systems including their anchoring mechanisms that are useful with the present basket-type EP catheter system 10, reference is made to U.S. Pat. Nos. 7,553,305, 8,056,207 and 8,540,697, all to Honebrink et al. and all of which are assigned to the assignee of the present invention and incorporated herein by reference. And, for a more thorough understanding of an anchor for a push-pull wire system, reference is made to U.S. Pat. No. 7,497,853 to Fischer et al., which is assigned to the assignee of the present invention and incorporated herein by reference.
In what is referred to as a transseptal approach in an exemplary cardiac ablation therapy to correct for atrial arrhythmia, an introducer sheath is introduced through a peripheral vein (typically a femoral vein) and advanced into the right atrium of a patient's cardiac muscle. After the introducer sheath is used to make an incision in the fossa ovalis (the tissue wall between the left and right atriums), the introducer is moved through the incision and anchored in the fossa ovalis. Next, the basket-type EP catheter system 10 of the present invention is steered or guided through the left atrium to orient the spline system 24 in a desired location within the left atrium, such as in proximity to a pulmonary vein where an ablation therapy is to be applied.
In an embodiment without push-pull wires, the physician advances the catheter body 12 and its spline system 24 toward a target myocardial site under fluoroscopy-guided observation. In an alternate embodiment with push-pull wires, the physician manipulates the handle assembly connected to the proximal end 12A of the catheter to selectively tension and relax the push-pull wires to control the orientation of the distal spline system 24 as it is advanced under fluoroscopy-guided observation toward a target myocardial site.
After determining that the distal electrode-carrying spline section of the catheter is in stable and steady contact with the endocardium surface of the heart chamber of interest, the EP catheter 10 of the present invention is used to generate an electro-anatomical map (EAM) of heart tissue. The goal is to determine the anatomical structure and physiological health of the heart. This is done by initiating many consecutive electrode sampling sequences where EGM samples indicative of electrical activity of the heart are sent from the various electrodes of the spline system 24 to the controller 16 for analysis and output to the physician in a useful format. Electrical activity is usually measured sequentially on a point-by-point basis at about 50 to 200 locations on the endocardium surface of the heart to construct an electro-anatomical depiction of the heart. The generated map then serves as the basis for deciding on a therapeutic course of action, for example, tissue ablation, to alter the propagation of the heart's electrical activity and to restore normal heart rhythm.
An accurate representation of cardiac anatomy is also useful for other medical applications such as congestive heart failure, injection of biologics into the heart and into scar tissue, anatomical guidance of biopsies, minimally invasive valve repair and replacement, and the like.
It is appreciated that various modifications to the inventive concepts described herein may be apparent to those of ordinary skill in the art without departing from the spirit and scope of the present invention as defined by the appended claims.
This application claims priority to U.S. Provisional Application Ser. No. 62/858,375, filed on Jun. 7, 2019.
| Number | Date | Country | |
|---|---|---|---|
| 62858375 | Jun 2019 | US |
