|Publication number||US20060089637 A1|
|Application number||US 11/179,333|
|Publication date||Apr 27, 2006|
|Filing date||Jul 12, 2005|
|Priority date||Oct 14, 2004|
|Also published as||CA2584016A1, EP1814482A2, EP1814482A4, EP1814482B1, US8486063, US20090030411, US20130331831, WO2006044794A2, WO2006044794A3|
|Publication number||11179333, 179333, US 2006/0089637 A1, US 2006/089637 A1, US 20060089637 A1, US 20060089637A1, US 2006089637 A1, US 2006089637A1, US-A1-20060089637, US-A1-2006089637, US2006/0089637A1, US2006/089637A1, US20060089637 A1, US20060089637A1, US2006089637 A1, US2006089637A1|
|Inventors||Randell Werneth, Marshall Sherman, Thomas Castellano, J. Flaherty, Gary Currie|
|Original Assignee||Werneth Randell L, Sherman Marshall L, Castellano Thomas M, Flaherty J C, Currie Gary E|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (71), Referenced by (167), Classifications (12), Legal Events (2)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This application claims the benefit of priority of U.S. Provisional Patent Application No. 60/618,753, filed Oct. 14, 2004, entitled “Ablation Catheter,” which is incorporated by reference herein in its entirety.
The present invention relates generally to catheters and methods for performing targeted tissue ablation in a subject. In particular, the present invention provides devices comprising catheters having distal ends configured to treat two dimensional regions of target tissue, including deployable distal ends, and methods for treating conditions (e.g., cardiac arrhythmias) with these and similar devices.
Tissue ablation is used in numerous medical procedures to treat a patient. Ablation can be performed to remove undesired tissue such as cancer cells. Ablation procedures may also involve the modification of the tissue without removal, such as to stop electrical propagation through the tissue in patients with an arrhythmia. Often the ablation is performed by passing energy, such as electrical energy, through one or more electrodes causing the tissue in contact with the electrodes to heats up to an ablative temperature. Ablation procedures can be performed on patients with atrial fibrillation by ablating tissue in the heart.
Mammalian organ function typically occurs through the transmission of electrical impulses from one tissue to another. A disturbance of such electrical transmission may lead to organ malfunction. One particular area where electrical impulse transmission is critical for proper organ function is in the heart. Normal sinus rhythm of the heart begins with the sinus node generating an electrical impulse that is propagated uniformly across the right and left atria to the atrioventricular node. Atrial contraction leads to the pumping of blood into the ventricles in a manner synchronous with the pulse.
Atrial fibrillation refers to a type of cardiac arrhythmia where there is disorganized electrical conduction in the atria causing rapid uncoordinated contractions that result in ineffective pumping of blood into the ventricle and a lack of synchrony. During atrial fibrillation, the atrioventricular node receives electrical impulses from numerous locations throughout the atria instead of only from the sinus node. This overwhelms the atrioventricular node into producing an irregular and rapid heartbeat. As a result, blood pools in the atria that increases a risk for blood clot formation. The major risk factors for atrial fibrillation include age, coronary artery disease, rheumatic heart disease, hypertension, diabetes, and thyrotoxicosis. Atrial fibrillation affects 7% of the population over age 65.
Atrial fibrillation treatment options are limited. Lifestyle change only assists individuals with lifestyle related atrial fibrillation. Medication therapy assists only in the management of atrial fibrillation symptoms, may present side effects more dangerous than atrial fibrillation, and fail to cure atrial fibrillation. Electrical cardioversion attempts to restore sinus rhythm but has a high recurrence rate. In addition, if there is a blood clot in the atria, cardioversion may cause the clot to leave the heart and travel to the brain or to some other part of the body, which may lead to stroke. What are needed are new methods for treating atrial fibrillation and other conditions involving disorganized electrical conduction.
Various ablation techniques have been proposed to treat atrial fibrillation, including the Cox-Maze procedure, linear ablation of various regions of the atrium, and circumferential ablation of pulmonary vein ostia. The Cox-Maze procedure and linear ablation procedures are tedious and time-consuming, taking several hours to accomplish. Pulmonary vein ostial ablation is proving to be difficult to do, and has lead to rapid stenosis and potential occlusion of the pulmonary veins. There is therefore a need for improved atrial ablation products and techniques.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various embodiments of the present invention, and, together with the description, serve to explain the principles of the invention. In the drawings:
Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
The present invention provides catheters for performing targeted tissue ablation in a subject. In preferred embodiments, the catheters comprise a tubular body member having a proximal end and distal end and preferably a lumen extending therebetween. The catheter is preferably of the type used for performing intracardiac procedures, typically being introduced from the femoral vein in a patient's leg. The catheter is preferably introducable through a sheath and also preferably has a steerable tip that allows positioning of the distal portion such as when the distal end of the catheter is within a heart chamber. The catheters include ablation elements mounted on a carrier assembly. The carrier assembly is attached to a coupler, which in turn is connected to a control shaft that is coaxially disposed and slidingly received within the lumen of the tubular body member. The carrier assembly is deployable from the distal end of the tubular body member by advancing the control shaft, such as to engage one or more ablation elements against cardiac tissue, typically atrial wall tissue or other endocardial tissue. Retraction of the control shaft causes the carrier assembly to be constrained within the lumen of the tubular body member.
Arrays of ablation elements, preferably electrode arrays, may be configured in a wide variety of ways and patterns. In particular, the present invention provides devices with electrode arrays that provide electrical energy, such as radiofrequency (RF) energy, in monopolar (unipolar), bipolar or combined monopolar-bipolar fashion, as well as methods for treating conditions (e.g., atrial fibrillation, supra ventricular tachycardia, atrial tachycardia, ventricular tachycardia, ventricular fibrillation, and the like) with these devices. Alternative to or in combination with ablation elements that deliver electrical energy to tissue, other forms and types of energy can be delivered including but not limited to: sound energy such as acoustic energy and ultrasound energy; electromagnetic energy such as electrical, magnetic, microwave and radiofrequency energies; thermal energy such as heat and cryogenic energies; chemical energy such as energy generated by delivery of a drug; light energy such as infrared and visible light energies; mechanical and physical energy; radiation; and combinations thereof.
As described above, the normal functioning of the heart relies on proper electrical impulse generation and transmission. In certain heart diseases (e.g., atrial fibrillation) proper electrical generation and transmission are disrupted or are otherwise abnormal. In order to prevent improper impulse generation and transmission from causing an undesired condition, the ablation catheters of the present invention may be employed.
One current method of treating cardiac arrhythmias is with catheter ablation therapy. Physicians make use of catheters to gain access into interior regions of the body. Catheters with attached electrode arrays or other ablating devices are used to create lesions that disrupt electrical pathways in cardiac tissue. In the treatment of cardiac arrhythmias, a specific area of cardiac tissue having aberrant conductive pathways, such as atrial rotors, emitting or conducting erratic electrical impulses, is initially localized. A user (e.g., a physician) directs a catheter through a main vein or artery into the interior region of the heart that is to be treated. The ablating element is next placed near the targeted cardiac tissue that is to be ablated. The physician directs energy, provided by a source external to the patient, from one ore more ablation elements to ablate the neighboring tissue and form a lesion. In general, the goal of catheter ablation therapy is to disrupt the electrical pathways in cardiac tissue to stop the emission of and/or prevent the propagation of erratic electric impulses, thereby curing the heart of the disorder. For treatment of atrial fibrillation, currently available methods and devices have shown only limited success and/or employ devices that are extremely difficult to use or otherwise impractical.
The ablation catheters of the present invention allow the generation of lesions of appropriate size and shape to treat conditions involving disorganized electrical conduction (e.g., atrial fibrillation). The ablation catheters of the present invention are also practical in terms of ease-of-use and limiting risk to the patient, as well as significantly reducing procedure times. The present invention addresses this need with, for example, spiral shaped and radial arm shaped (also called umbrella shaped) carrier assemblies whose ablation elements create spiral, radial, or other simple or complex shaped patterns of lesions in the endocardial surface of the atria by delivery of energy to tissue or other means. The lesions created by the ablation catheters are suitable for inhibiting the propagation of inappropriate electrical impulses in the heart for prevention of reentrant arrhythmias.
Definitions. To facilitate an understanding of the invention, a number of terms are defined below.
As used herein, the terms “subject” and “patient” refer to any animal, such as a mammal like livestock, pets, and preferably a human. Specific examples of “subjects” and “patients” include, but are not limited, to individuals requiring medical assistance, and in particular, requiring atrial fibrillation catheter ablation treatment.
As used herein, the terms “catheter ablation” or “ablation procedures” or “ablation therapy,” and like terms, refer to what is generally known as tissue destruction procedures. Ablation is often used in treating several medical conditions, including abnormal heart rhythms. It can be performed both surgically and non-surgically. Non-surgical ablation is typically performed in a special lab called the electrophysiology (EP) laboratory. During this non-surgical procedure a catheter is inserted into the heart using fluoroscopy for visualization, and then an energy delivery apparatus is used to direct energy to the heart muscle. This energy either “disconnects” or “isolates” the pathway of the abnormal rhythm (depending on the type of ablation). It can also be used to disconnect the conductive pathway between the upper chambers (atria) and the lower chambers (ventricles) of the heart. For individuals requiring heart surgery, ablation can be performed during coronary artery bypass or valve surgery.
As used herein, the term “ablation element” refers to an energy delivery element, such as an electrode for delivering electrical energy. Ablation elements can be configured to deliver multiple types of energy, such as ultrasound energy and cryogenic energy, either simultaneously or serially. Electrodes can be constructed of a conductive plate, wire coil, or other means of conducting electrical energy through contacting tissue. In monopolar energy delivery, the energy is conducted from the electrode, through the tissue to a ground pad, such as a conductive pad attached to the back of the patient. The high concentration of energy at the electrode site causes localized tissue ablation. In bipolar energy delivery, the energy is conducted from a first electrode to one or more separate electrodes, relatively local to the first electrode, through the tissue between the associated electrodes. Bipolar energy delivery results in more precise, shallow lesions while monopolar delivery results in deeper lesions. Both monopolar and bipolar delivery provide advantages, and the combination of their use is a preferred embodiment of this application. Energy can also be delivered using pulse width modulated drive signals, well known to those of skill in the art. Energy can also be delivered in a closed loop fashion, such as a system with temperature feedback wherein the temperature modifies the type, frequency and or magnitude of the energy delivered.
As used herein, the term “carrier assembly” refers to a flexible carrier, on which one or more ablation elements are disposed. Carrier assemblies are not limited to any particular size, or shape, and can be configured to be constrained within an appropriately sized lumen.
As used herein, the term “spiral tip” refers to a carrier assembly configured in its fully expanded state into the shape of a spiral. The spiral tip is not limited in the number of spirals it may contain. Examples include, but are not limited to, a wire tip body with one spiral, two spirals, ten spirals, and a half of a spiral. The spirals can lie in a relatively single plane, or in multiple planes. A spiral tip may be configured for energy delivery during an ablation procedure.
As used herein the term “umbrella tip” refers to a carrier assembly with a geometric center which lies at a point along the axis of the distal portion of the tubular body member, with one or more bendable or hinged carrier arms extending from the geometric center, in an umbrella configuration. Each carrier arm may include one or more ablation elements. Each carrier arm of an umbrella tip includes a proximal arm segment and a distal arm segment, the distal arm segment more distal than the proximal arm segment when the carrier assembly is in a fully expanded condition. One or more additional carrier arms can be included which include no ablation elements, such as carrier arms used to provide support or cause a particular deflection. An umbrella tip body is not limited to any particular size. An umbrella tip may be configured for energy delivery during an ablation procedure.
As used herein, the term “lesion,” or “ablation lesion,” and like terms, refers to tissue that has received ablation therapy. Examples include, but are not limited to, scars, scabs, dead tissue, burned tissue and tissue with conductive pathways that have been made highly resistive or disconnected.
As used herein, the term “spiral lesion” refers to an ablation lesion delivered through a spiral tip ablation catheter. Examples include, but are not limited to, lesions in the shape of a wide spiral, and a narrow spiral, a continuous spiral and a discontinuous spiral.
As used herein, the term “umbrella lesion” or “radial lesion,” and like terms, refers to an ablation lesion delivered through an umbrella tip ablation catheter. Examples include, but are not limited to, lesions with five equilateral prongs extending from center point, lesions with four equilateral prongs extending from center point, lesions with three equilateral prongs extending from center point, and lesions with three to five non-equilateral prongs extending from center point.
As used herein, the term “coupler” refers to an element that connects the carrier assembly to the control shaft. Multiple shafts, or ends of the carrier assembly may connect to the coupler. Multiple carrier arms can have one or more of their ends attached to the coupler. The coupler may include anti-rotation means that work in combination with mating means in the tubular body member. Couplers may be constructed of one or more materials such as polyurethane, steel, titanium, and polyethylene.
As used herein, the term “carrier arm” refers to a wire-like shaft capable of interfacing with electrodes and the coupler. A carrier arm is not limited to any size or measurement. Examples include, but are not limited to: stainless steel shafts; Nitinol shafts; titanium shafts; polyurethane shafts; nylon shafts; and steel shafts. Carrier arms can be entirely flexible, or may include flexible and rigid segments.
As used herein, the term “carrier arm bend point” refers to a joint (e.g., junction, flexion point) located on a carrier arm. The degree of flexion for a carrier arm bend point may range from 0 to 360 degrees. The bend portion can be manufactured such what when the carrier assembly is fully expanded the bend point is positioned in a relatively straight portion, a curved portion, or in a discrete transition from a first direction to a second transition, such as a 45 degree bend transition. The bend portion can include one or more flexing means such as a spring, a reduced diameter segment, or a segment of increased flexibility.
The present invention provides structures that embody aspects of the ablation catheter. The present invention also provides tissue ablation systems and methods for using such ablation systems. The illustrated and preferred embodiments discuss these structures and techniques in the context of catheter-based cardiac ablation. These structures, systems, and techniques are well suited for use in the field of cardiac ablation.
However, it should be appreciated that the invention is applicable for use in other tissue ablation applications such as tumor ablation procedures. For example, the various aspects of the invention have application in procedures for ablating tissue in the prostrate, brain, gall bladder, uterus, and other regions of the body, preferably regions with an accessible wall or flat tissue surface, using systems that are not necessarily catheter-based.
The multifunctional catheters of the present invention have advantages over previous prior art devices.
To accomplish this, catheter 100 is inserted into the right atrium 2, preferably through the inferior vena cava 20, as shown in the illustration, or through the superior vena cava 21. Catheter 100 may include an integral sheath, such as a tip deflecting sheath, or may work in combination with a separate sheath. When passing into the left atrium, the catheter passes through or penetrates the fossa ovalis 7, such as over a guide wire placed by a trans-septal puncture device. The catheter 100 carries a structure carrying multiple ablation elements such as RF electrodes, carrier assembly 120, into the left atrium. Carrier assembly 120 is adapted to be deformable such that pressing carrier assembly into left atrial wall 9 will cause one or more, and preferably all of electrodes 130 to make contact with tissue to be analyzed and/or ablated. Each of the electrodes 130 is attached via connecting wires to an energy delivery apparatus, RF delivery unit 200 which is also attached to patch electrode 25, preferably a conductive pad attached to the back of the patient.
RF delivery unit 200 is configured to delivery RF energy in monopolar, bipolar or combination monopolar-bipolar energy delivery modes. In a preferred embodiment, monopolar energy delivery is followed by bipolar energy delivery, which is then followed a period without energy delivery, such as a sequence in which the three steps are have equal durations. In another preferred embodiment, RF delivery unit 200 is configured to also provide electrical mapping of the tissue that is contacted by one or more electrodes integral to carrier assembly 120. Electrodes 130 can also be configured to be mapping electrodes and/or additional electrodes can be integral to carrier assembly 120 to provide a mapping function. Carrier assembly 120 is configured to be engaged over an endocardial surface to map and/or ablate tissue on the surface. RF energy is delivered after a proper location of the electrodes 130 is confirmed with a mapping procedure. If the position is determined to be inadequate, carrier assembly 120 is repositioned through various manipulations at the proximal end of the ablation catheter 100. In another preferred embodiment, RF delivery unit 200 is configured to delivery both RF energy and ultrasound energy the identical or different electrodes 130. In another preferred embodiment, RF delivery unit 200 is configured to accept a signal from one or more sensors integral to ablation catheter 100, not shown, such that the energy delivered can be modified via an algorithm which processes the information received from the one or more sensors.
Referring now to
Control shaft 150 extends from the proximal end to distal end 102 of catheter shaft 101 and resides in a lumen therebetween. Control shaft 150 is also constructed of material to provide suitable flexibility and column strength to be percutaneously introduced into the patient as well as perform other functions such as the advancement and contraction of carrier assembly 120. Applicable materials for control shaft 150 are Nitinol™; stainless steel; titanium; gold; platinum; copper; a polymer; a polymer embedded with conductive material; an elastomer; a plastic; and combinations thereof. In a preferred embodiment, control shaft 150 is constructed of both stainless steel and Nitinol. In another preferred embodiment, control shaft 150 is selected from the group consisting of: a monofilament fiber; a spring coil; a wire; and combinations thereof. In another preferred embodiment, control shaft 150 has a guidewire construction such as a core with a tightly coiled wire sheath, the sheath surrounding a substantial length of the core. In another preferred embodiment, the control shaft 150 includes a lumen from its proximal end and its distal end 102 such as to permit over-the-wire introduction via that lumen.
Coupler 140, located at the distal end 102 of control shaft 150 connects control shaft 150 to carrier assembly 120. Carrier assembly 120 is a flexible filamentous assembly that includes at least one ablation element, such as electrode 130, to deliver energy to tissue. Carrier assembly 120 includes one or more carrier arms 123, each of which has a proximal arm segment 125 and a distal arm segment 127, which are connected by a resiliently flexible segment, carrier arm bend portion 121. Bend portion 121 may include various elements to assist in bending such as a spring; a hinge; a reduced diameter segment; a bend created during a heat treatment of a wire such as the “training” of a Nitinol wire; and combinations thereof. Bend point 121 provides means for rotatably joining the distal arm segment 127 to the proximal arm segment 125. Carrier arms 123 are preferably constructed of a wire, such as a ribbon wire, and may have segments with different levels of flexibility. Bend point 121 may comprises two or more wires bonded together with a joint. Carrier arms 123 may include no ablation elements, such as a carrier arm 123 to provide support only. Carrier arms 123 may also include mapping electrodes, thermal sensors or other sensors, with or without the inclusion of ablation elements. In a preferred embodiment, each carrier arm 123 includes at least one ablation element.
Carrier assembly 120 can be configured to assume various geometries when in its expanded condition, such as the umbrella configuration of
Each electrode 130 of carrier assembly 120 of ablation catheter 100 is connected to one or more wires, not shown but preferably extending from each electrode 130 of the distal arm segment 127, running parallel with the segment toward the axis of distal end 102 of the catheter shaft 101, then traveling proximally toward coupler 140 and then through catheter shaft 101 to handle 110. The wires may pass through coupler 140, along side coupler 140, or may be electrically connected to coupler 140 such that these wires connect to wires on the proximal end of coupler 140. The wires may be within a lumen internal to control shaft 150, a space between control shaft 150 and catheter shaft 101, and a separate lumen of catheter shaft 101. The wires are looped within handle 110 to provide the distension necessary for the resilient deployment of carrier assembly 120 as illustrated in
The electrode 130 wires provide a drive signal and a ground signal, or two or more alternating drive signals to each electrode 130. Electrodes 130 can be wired independently, such that each electrode 130 can deliver energy independent of any other electrode, or two or more electrodes can be connected in parallel or serial fashion. In a preferred embodiment, ablation catheter 100 and an energy delivery apparatus can be configured to drive two ablation elements, such as electrodes 130, independently or simultaneously. Handle 110 includes RF attachment port 181 which can be connected to a separate energy delivery apparatus such as an RF delivery apparatus. Mapping port 182 is also included, which can be used to connect to a mapping device to assist in determining and/or confirming the proper ablation location. Handle 110 further includes button 116, which is connected to switch means, not shown, for starting and/or stopping the delivery of energy to one or more of electrodes 130. In an alternative embodiment, an energy delivery apparatus is integrated into handle 110 such that a separate apparatus and port 181 are not needed. In this configuration, handle 110 may include a plug, not shown, for attachment to a power supply or wall outlet. In another alternative embodiment, handle 110 includes an audible transducer, such as an audible transducer that is activated when energy is being delivered to tissue, or an alarm condition has been entered. In another alternative embodiment, handle 110 includes a power supply, such as a battery or rechargeable battery, both not shown. In another alternative embodiment, ablation catheter 100 includes one or more elements requiring power such as from an integrated battery, these elements selected from the group consisting of: an integral a light such as an LED; a display such as a liquid crystal display or touch screen display; an audible transducer; a tactile transducer such as a vibration transducer which readily alerts anyone holding the device; a relay such as a relay which disconnects power to one or more ablation elements; mapping circuitry embedded in one or more components of ablation catheter 100, or electrode 130; and combinations thereof.
Referring now to
Referring now to
Electrodes 130 are mounted to distal arm segment 127 of carrier arms 123. These electrodes can consist of wire coils; conductive plates; semiconductor plates; and combinations thereof. Each electrode is connected to one or more wires, each wire traveling from the electrode inward toward the axis of catheter shaft axis, and then proximal toward the end of control shaft 150. The wires are joined in a bundle, wire bundle 151 which travels along side control shaft 150. Wire bundle 151 may be glued or banded to control shaft 150 to avoid binding. In an alternative embodiment, wire bundle 151 travels internal to control shaft 150.
Carrier arm 123 includes proximal arm segment 125 and distal arm segment 127, carrier arm bend point 121. In the configuration of
Referring now to
Referring now to
Referring again to
Control shaft 150 is mechanically attached to coupler 140. Control shaft 150 extends proximally to handle 110 and is operably connected to knob 115 such that rotation of knob 115 from a deployed position to a withdrawn position causes carrier assembly 120 to be constrained within a lumen of catheter shaft 101, and rotation of knob 115 from a withdrawn position to a deployed position causes carrier assembly 120 to extend beyond the distal end of catheter shaft 101 to be in an expanded condition. In a preferred embodiment, knob 115 is operably connected to control shaft 150 via a cam, or set of gears, not shown, to provide a mechanical advantage in the distance traveled by control shaft 150.
Catheter shaft 101 is preferably part of a steerable sheath, steering mechanism not shown, and includes flush port 170, which is configured to be attachable to a flushing syringe, used to flush blood and other debris or contaminants from the lumen of an empty catheter shaft 101 (wherein control shaft 150, coupler 140 and carrier assembly 120 have been removed) or for flushing the space between control shaft 150 and the inner wall of catheter shaft 101. Catheter shaft 101 is not connected to handle 110, such that handle 110 can be withdrawn, removing control shaft 150, coupler 140 and carrier assembly 120 from catheter shaft 101. This configuration is useful when these components are provided in a kit form, including combinations of different versions of these components, the different combinations made available to treat multiple patients, or a single patient requiring multiple electrode patterns. A preferred example of a kit would include the catheter shaft 101 and flush port 170 of
Also depicted in
In a preferred embodiment, ablation catheter 100 includes an embedded identifier (ID), an uploadable electronic or other code, which can be used by RF delivery unit 200 to confirm compatibility and other acceptability of the specific catheter 100 with the specific RF delivery unit 200. The electronic code can be a bar code, not shown, on handle 110 which is read by RF delivery unit 200, an electronic code which is transferred to RF delivery unit 200 via a wired or wireless connection, not shown, or other identifying means, such as an RF tag embedded in handle 110. In another preferred embodiment, RF delivery unit 200 also includes an embedded ID, such as an ID which can be downloaded to catheter 100 for a second or alternative acceptability check. The embedded ID can also be used to automatically set certain parameters or certain parameter ranges, and can be used to increase safety by preventing inadvertent settings outside of an acceptable range for the specific catheter 100.
Handle 110 includes two push buttons, first button 116 and second button 117. These buttons can be used to perform one or more functions, and can work in cooperation with user input components of user interface 201 such that commands entered into user interface 201 set the action taken when either or both button 116 and button 117 are pressed. In a preferred embodiment, both button 116 and button 117 must be pressed simultaneously to deliver energy to one or more ablation elements of catheter 100. At the distal end of catheter shaft 101 is a circumferential band, band 104. Band 104 is preferably a visualization marker, such as a radiographic marker, ultrasound marker, electromagnetic marker, magnetic marker and combinations thereof. In an alternative embodiment, band 104 transmits or receives energy, such as when the marker is used as a ground or other electrode during an ablation. In another alternative embodiment, band 104 is an antenna used to determine the position of the distal end of catheter shaft 101 or the location of another component in relation to band 104. In another preferred embodiment, band 104 is used to store energy, such as capacitively stored energy that can be used to generate a magnetic field or to deliver ablation energy.
Referring now to
Referring back to
Coupler 140 is mechanically attached to control shaft 150 which is mechanically attached to coupler 140. Control shaft 150 extends proximally to handle 110 and is operably connected to sliding knob 111, wherein sliding knob 111 can be distally advanced or proximally retracted in slot 112. Retraction of knob 111 from a distal position to a proximal position causes carrier assembly 120 to be constrained within a lumen at distal end 102 of catheter shaft 101, and advancement of knob 111 from a proximal position to a distal position causes carrier assembly 120 to extend beyond distal end 102 of catheter shaft 101, carrier assembly 120 resiliently expanding to its spiral shaped tip. In a preferred embodiment, knob 111 is operably connected to control shaft 150 via a cam, or set of gears, not shown, to provide a mechanical advantage in the distance traveled by control shaft 150, or the force exerted on control shaft 150.
Catheter shaft 101 is part of a steerable sheath, including pull wire 105 which is secured at one end to the distal end of control shaft 150 and at the other end is operably attached to knob 113, wherein sliding knob 113 can be distally advanced or proximally retracted in slot 114. The pull wire is operably connected to the control knob 113 so that sliding of the control knob pulls pull wire 105 to effectuate steering of the distal end 102 of control shaft 150. Retraction of knob 113 proximally causes distal end of control shaft 150 to deflect and advancement of knob 113 distally causes the distal end of control shaft 150 to straighten. Using knob 113, the operator can steer the carrier assembly 120 as needed to contact different areas of the atrium wall or other tissue surface. The pull wire 105 may be unsecured to the control shaft 150 along much of its length, or it may be embedded in the control shaft 150 wall or otherwise restrained to the control shaft 150. The entire distal end of the ablation catheter 100 may also be steered with pull wire 105, as the catheter shaft 101 is sufficiently flexible that it will deform along with the control shaft 150. In an additional or alternative embodiment, a second pull wire, not shown, is attached to the distal end of catheter shaft 101, this pull wire similarly attached to control means included in handle 101. In a preferred embodiment, knob 112 is operably connected to pull wire 105 via a cam, or set of gears, not shown, to provide a mechanical advantage in the distance traveled by pull wire 105, or the force exerted on pull wire 105. In an alternative or additional embodiment, a pull wire and handle control means can be connected to either catheter shaft 101 and/or control shaft 150 and/or coupler 140 and/or carrier assembly 120 at any location along their length, to cause a specific deflection pattern. In another preferred embodiment, the shaft to which the pull wire is attached includes multiple discrete levels of stiffness and/or variable levels of stiffness, near the attachment point, such that non-continuous bending occurs, i.e. bending with multiple radii or continuously variable radii.
Catheter shaft 101 includes flush port 170, which is configured to be attachable to a flushing syringe, used to flush blood and other contaminants from the lumen of an empty catheter shaft 101 (wherein control shaft 150, coupler 140 and carrier assembly 120 have been removed) or for flushing the space between control shaft 150 and the inner wall of catheter shaft 101. In a preferred embodiment, catheter shaft 101 is not connected to handle 110, such that handle 110 can be withdrawn, removing control shaft 150, coupler 140 and carrier assembly 120 from catheter shaft 101. This configuration is useful when these components are provided in a kit form, including combinations of different versions of these components, these different combinations made available to treat multiple patients, or a single patient.
Also depicted in
In a preferred embodiment, ablation catheter 100 and/or RF delivery unit 200 include an embedded identifier (ID), an uploadable or downloadable electronic or other code, which can be used by the system to confirm component compatibility and/or other acceptability of the specific catheter 100 with the specific RF delivery unit 200. The electronic code and some of its uses have been described in detail in reference to
Referring now to
Included in the carrier assembly 120 are four electrodes 130, noting that one or more electrodes should be considered within the scope of this application. Carrier assembly 120 includes a carrier wire 128, to which the electrodes 130 are mounted. Carrier wire 128 is preferably a non-conductive wire, such as a Teflon™ coated Nitinol wire, or a braided nylon line such that the electrodes can be electrically isolated from carrier wire 128. Alternatively, each electrode 130 can include an insulator. At each end of carrier assembly 120, carrier wire 128 transitions to wire 129′ and wire 129″ through transition point 122′ and transition point 122″ respectively. Depicted in
Carrier assembly 120 can be constrained within lumen 107 catheter shaft 101 by retracting wire 129′, wire 129″ or both. Utilizing control means incorporated into a handle, both not shown but described in detail in reference to previous figures, these advancements can be accomplished by an operator. Referring specifically to
Referring now to
Referring now to
Electrode assembly 230 further includes sensor 233, which can be an individual sensor or bank of multiple sensors such as a sensor to sense one or more of: chemical activity, light characteristic such as intensity or wavelength, electrical activity, pH, temperature, pressure, fluid flow or other physiologic parameter. Electrode assembly 230 further includes sensor interface 234 which includes various electronic components and circuitry such as circuitry created in various doping and other integrated circuit building processes used in a semiconductor substrate such as silicon. The information provided by sensor 233 can be processed by sensor interface 234 and/or by circuitry included in a proximal handle or energy delivery apparatus. This information can be used to start, stop, increase, decrease or otherwise modify energy delivery or control another function of electrode assembly 230 or another function of the ablation catheter of the present invention.
Electrode assembly 230 further includes mapping electrode 232 which provides recording of electrical signals of the heart, such as signals used to identify rotors to be ablated during the procedure. In an alternative embodiment, ablation electrode 231 is used to record the electrical signals of the heat. Electrode assembly 230 further includes functional element 237, which may include integrated circuit components described above, as well as MEMS or nano-machine components that are well known to being integrated into semiconductor substrates using the appropriate machinery. A preferred embodiment of
Multiple semiconductor portions can be integrated into electrode assembly 230, such as portions which are connected with an insulating material and/or a flexible material providing a flexible joint between rigid portions of electrode assembly 230. Utilizing semiconductor technology and/or MEMS or other semiconductor fabrication means, numerous functions can be incorporated into electrode assembly 230 to improve therapeutic benefit of the procedure, provide enhanced safety to the procedure, or provide other therapeutic or non-therapeutic benefit to the patient or the operator of the system. In an alternative embodiment, the electrode assembly further comprises a cooling element, such as a heat sink, not shown.
Referring now to
Another alternative embodiment of the ablation catheter of the present invention is also depicted in
Referring now to
It should be understood that numerous other configurations of the systems, devices and methods described herein can be employed without departing from the spirit or scope of this application. It should be understood that the system includes multiple functional components, such as the ablation catheter and the energy delivery apparatus. The ablation catheter consists of a catheter shaft, a carrier assembly for providing electrodes in a resiliently biased configuration, a control shaft for deploying and withdrawing the carrier assembly, and a coupler for attaching the control shaft to the carrier assembly. The carrier assembly is a support structure which is shiftable from a storage or confined configuration, such as a radially constrained configuration, to a deployed or expanded configuration. The carrier assembly can includes wires, ribbons, cables and struts, made of either metals, non-metals or combinations of both. The carrier assembly can be constructed of one or more materials, including both metals and non-metals. Typical metals chosen for carrier assembly construction include but are not limited to: stainless steel, Nitinol, Elgiloy™, other alloys and combinations thereof.
The ablation catheter of the present invention may include a steerable outer sheath, or may work in conjunction as a system with a separate steerable outer sheath. One or more tubular components of the ablation catheter may be steerable such as with the inclusion of a controllable pull wire at or near the distal end. The ablation catheter of the present invention may be inserted over the wire, such as via a lumen within one of the tubular conduits such as within a lumen of the tubular body member or control shaft, or alternatively the catheter may include a rapid exchange sidecar at or near its distal end, consisting of a small projection with a guidewire lumen therethrough. A guidewire lumen may be included solely for the guidewire, or may provide other functions such as a vacuum lumen for an integral suction port integrated at the distal portion of the carrier assembly.
The ablation catheter of the present invention further includes ablation elements. In preferred embodiments, one or more ablation elements are electrodes configured to deliver RF energy. Other forms of energy, alternative or in addition to RF, may be delivered, including but not limited to: acoustic energy and ultrasound energy; electromagnetic energy such as electrical, magnetic, microwave and radiofrequency energies; thermal energy such as heat and cryogenic energies; chemical energy; light energy such as infrared and visible light energies; mechanical energy; radiation; and combinations thereof. One or more ablation elements may comprise a drug delivery pump or a device to cause mechanical tissue damage such as a forwardly advanceable spike or needle. The ablation elements can deliver energy individually, in combination with or in serial fashion with other ablation elements. The ablation elements can be electrically connected in parallel, in series, individually, or combinations thereof. The ablation catheter may include cooling means to prevent undesired tissue damage and/or blood clotting. The ablation elements may be constructed of various materials, such as plates of metal and coils of wire for RF energy delivery. The electrodes can take on various shapes including shapes used to focus energy such as a horn shape to focus sound energy, and shapes to assist in cooling such as a geometry providing large surface area. Electrodes can vary within a single carrier assembly, such as a spiral array of electrodes or a umbrella tip configuration wherein electrodes farthest from the central axis of the catheter have the largest major axis. Wires and other flexible conduits are attached to the ablation elements, such as electrical energy carrying wires for RF electrodes or ultrasound crystals, and tubes for cryogenic delivery.
The ablation elements requiring electrical energy to ablate require wired connections to an electrical energy power source such as an RF power source. In configurations with large numbers of electrodes, individual pairs of wires for each electrode may be bulky and compromise the cross-sectional profile of the ablation catheter. In an alternative embodiment, one or more electrodes, connected in serial fashion such that a reduced number of wires, such as two wires, can be attached to two or more electrodes, include switching means such that while a first electrode is powered, the remaining electrodes do not transmit ablative energy. Switching means may be a thermal switch, such that as a first electrodes heats up, a single pole double throw switch change state disconnecting power from that electrode and attaching power to the next electrode in the serial connection. This integral temperature switch may have a first temperature to disconnect the electrode, and a second temperature to reconnect the electrode wherein the second temperature is lower than the first temperature, such as a second temperature below body temperature. In an alternative embodiment, each electrode is constructed of materials in their conductive path such that as when the temperature increased and reached a predetermined threshold, the resistance abruptly decreased to near zero, such that power dissipation, or heat, generated by the electrode was also near zero, and more power could be delivered to the next electrode incorporating the above switching means.
The ablation catheter of the present invention preferably includes a handle activating or otherwise controlling one or more functions of the ablation catheter. The handle may include various knobs, such as rotating or sliding knobs which are operably connected to advanceable conduits, or are operably connected to gear trains or cams which are connected to advanceable conduits. These knobs, such as knobs use to deflect a distal portion of a conduit, or to advance or retract the carrier assembly, preferably include a reversible locking mechanism such that a particular tip deflection or deployment amount can be maintained through various manipulations of the system.
The ablation catheter may include one or more sensors, such as sensors used to detect chemical activity; light; electrical activity; pH; temperature; pressure; fluid flow or another physiologic parameter. These sensors can be used to map electrical activity, measure temperature, or gather other information that may be used to modify the ablation procedure. In a preferred embodiment, one or more sensors, such as a mapping electrode, can also be used to ablate tissue.
Numerous components internal to the patient, such as the carrier assembly or electrodes, may include one or more visual markers such as radiopaque markers visible under fluoroscopy, or ultrasound markers.
Selection of the tissue to be ablated may be based on a diagnosis of aberrant conduit or conduits, or based on anatomical location. RF energy may be delivered first, followed by another energy type in the same location, such as when a single electrode can deliver more than one type of energy, such as RF and ultrasound energy. Alternatively or additionally, a first procedure may be performed utilizing one type of energy, followed by a second procedure utilizing a different form of energy. The second procedure may be performed shortly after the first procedure, such as within four hours, or at a later date such as greater than twenty-four hours after the first procedure. Numerous types of tissue can be ablated utilizing the devices, systems and methods of the present invention. For example, the various aspects of the invention have application in procedures for ablating tissue in the prostrate, brain, gall bladder, uterus, other organs and regions of the body, and a tumor, preferably regions with an accessible wall or flat tissue surface. In the preferred embodiment, heart tissue is ablated, such as left atrial tissue.
In another preferred embodiment of the system of the present invention, an ablation catheter and a heat sensing technology are included. The heat sensing technology, includes sensor means that may be placed on the chest of the patient, the esophagus or another area in close enough proximity to the tissue being ablated to directly measure temperature effects of the ablation, such as via a temperature sensor, or indirectly such as through the use of an infrared camera. In the described system, when a temperature or a surrogate temperature reaches a threshold, such as an adjustable threshold, the ablation energy is reduced or stopped, to one or more ablation elements. The threshold will depend on the location of the sensor means, as well as where the ablation energy is being delivered. The threshold may be adjustable, and may be automatically configured.
Numerous kit configurations are also to be considered within the scope of this application. An ablation catheter is provided with multiple carrier assemblies. These carrier assemblies can be removed for the tubular body member of the catheter, or may include multiple tubular body members in the kit. The multiple carrier assemblies can have different patterns, different types or amounts of electrodes, and have numerous other configurations including compatibility with different forms of energy.
Though the ablation device has been described in terms of its preferred endocardial and transcutaneous method of use, the array may be used on the heart during open heart surgery, open chest surgery, or minimally invasive thoracic surgery. Thus, during open chest surgery, a short catheter or cannula carrying the carrier assembly and its electrodes may be inserted into the heart, such as through the left atrial appendage or an incision in the atrium wall, to apply the electrodes to the tissue to be ablated. Also, the carrier assembly and its electrodes may be applied to the epicardial surface of the atrium or other areas of the heart to detect and/or ablate arrhythmogenic foci from outside the heart.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. In addition, where this application has listed the steps of a method or procedure in a specific order, it may be possible, or even expedient in certain circumstances, to change the order in which some steps are performed, and it is intended that the particular steps of the method or procedure claim set forth herebelow not be construed as being order-specific unless such order specificity is expressly stated in the claim.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3951136 *||Oct 7, 1974||Apr 20, 1976||Vital Signs, Inc.||Multiple purpose esophageal probe|
|US4017903 *||Aug 27, 1975||Apr 12, 1977||Hewlett-Packard Company||Pulse code modulation recording and/or reproducing system|
|US4112952 *||Feb 11, 1977||Sep 12, 1978||The United States Of America As Represented By The Secretary Of Health, Education And Welfare||Electrode for artificial pacemaker|
|US4699147 *||Sep 25, 1985||Oct 13, 1987||Cordis Corporation||Intraventricular multielectrode cardial mapping probe and method for using same|
|US4907589 *||Apr 29, 1988||Mar 13, 1990||Cosman Eric R||Automatic over-temperature control apparatus for a therapeutic heating device|
|US5010894 *||Jan 9, 1989||Apr 30, 1991||Edhag Knut O||Intravascular electrode lead usable for cardiac defibrillation|
|US5100423 *||Aug 21, 1990||Mar 31, 1992||Medical Engineering & Development Institute, Inc.||Ablation catheter|
|US5184621 *||May 29, 1991||Feb 9, 1993||C. R. Bard, Inc.||Steerable guidewire having electrodes for measuring vessel cross-section and blood flow|
|US5230349 *||Jun 4, 1992||Jul 27, 1993||Sensor Electronics, Inc.||Electrical heating catheter|
|US5234004 *||Mar 12, 1991||Aug 10, 1993||Technomed International||Method and apparatus for the surgical treatment of tissues by thermal effect, and in particular the prostate, using a urethral microwave-emitting probe means|
|US5281213 *||Apr 16, 1992||Jan 25, 1994||Implemed, Inc.||Catheter for ice mapping and ablation|
|US5313943 *||Sep 25, 1992||May 24, 1994||Ep Technologies, Inc.||Catheters and methods for performing cardiac diagnosis and treatment|
|US5334193 *||Nov 13, 1992||Aug 2, 1994||American Cardiac Ablation Co., Inc.||Fluid cooled ablation catheter|
|US5342357 *||Nov 13, 1992||Aug 30, 1994||American Cardiac Ablation Co., Inc.||Fluid cooled electrosurgical cauterization system|
|US5348554 *||Dec 1, 1992||Sep 20, 1994||Cardiac Pathways Corporation||Catheter for RF ablation with cooled electrode|
|US5370644 *||Jul 16, 1993||Dec 6, 1994||Sensor Electronics, Inc.||Radiofrequency ablation catheter|
|US5411025 *||Jun 30, 1992||May 2, 1995||Cordis Webster, Inc.||Cardiovascular catheter with laterally stable basket-shaped electrode array|
|US5423811 *||Mar 16, 1994||Jun 13, 1995||Cardiac Pathways Corporation||Method for RF ablation using cooled electrode|
|US5462521 *||Dec 21, 1993||Oct 31, 1995||Angeion Corporation||Fluid cooled and perfused tip for a catheter|
|US5471982 *||Sep 29, 1992||Dec 5, 1995||Ep Technologies, Inc.||Cardiac mapping and ablation systems|
|US5536267 *||Aug 12, 1994||Jul 16, 1996||Zomed International||Multiple electrode ablation apparatus|
|US5545161 *||Oct 7, 1994||Aug 13, 1996||Cardiac Pathways Corporation||Catheter for RF ablation having cooled electrode with electrically insulated sleeve|
|US5562720 *||Oct 6, 1994||Oct 8, 1996||Vesta Medical, Inc.||Bipolar/monopolar endometrial ablation device and method|
|US5606974 *||May 2, 1995||Mar 4, 1997||Heart Rhythm Technologies, Inc.||Catheter having ultrasonic device|
|US5651780 *||Dec 22, 1994||Jul 29, 1997||Ep Technologies, Inc.||Systems for identifying catheters and monitoring their use|
|US5673695 *||Nov 6, 1996||Oct 7, 1997||Ep Technologies, Inc.||Methods for locating and ablating accessory pathways in the heart|
|US5702438 *||Jun 8, 1995||Dec 30, 1997||Avitall; Boaz||Expandable recording and ablation catheter system|
|US5722401 *||Nov 13, 1995||Mar 3, 1998||Cardiac Pathways Corporation||Endocardial mapping and/or ablation catheter probe|
|US5911720 *||Nov 26, 1996||Jun 15, 1999||Ep Technologies, Inc.||Ablation catheter with segmented tip|
|US5954719 *||Mar 23, 1998||Sep 21, 1999||Irvine Biomedical, Inc.||System for operating a RF ablation generator|
|US5989245 *||Mar 31, 1997||Nov 23, 1999||Prescott; Marvin A.||Method and apparatus for therapeutic laser treatment|
|US6032674 *||Dec 31, 1997||Mar 7, 2000||Arthrocare Corporation||Systems and methods for myocardial revascularization|
|US6053937 *||Nov 4, 1997||Apr 25, 2000||Rita Medical Systems, Inc.||Multiple electrode ablation apparatus and method with cooling element|
|US6063082 *||Mar 5, 1998||May 16, 2000||Scimed Life Systems, Inc.||Percutaneous myocardial revascularization basket delivery system and radiofrequency therapeutic device|
|US6071282 *||Dec 3, 1998||Jun 6, 2000||Ep Technologies, Inc.||Structures for deploying electrode elements|
|US6231570 *||Jun 15, 1998||May 15, 2001||Hosheng Tu||Electrode catheter system for tissue ablation|
|US6264653 *||Sep 24, 1999||Jul 24, 2001||C. R. Band, Inc.||System and method for gauging the amount of electrode-tissue contact using pulsed radio frequency energy|
|US6319249 *||Apr 14, 1999||Nov 20, 2001||Biotronik Mess-Und Therapiegeraete Gmbh & Co. Ingenieurbuero Berlin||Ablation system|
|US6319251 *||Jan 24, 2000||Nov 20, 2001||Hosheng Tu||Medical device and methods for treating intravascular restenosis|
|US6425894 *||Jul 12, 2000||Jul 30, 2002||Biosense Webster, Inc.||Ablation catheter with electrode temperature monitoring|
|US6488678 *||Jan 10, 2001||Dec 3, 2002||Cardiac Pacemakers, Inc.||RF ablation apparatus and method using unipolar and bipolar techniques|
|US6530922 *||Jan 27, 2000||Mar 11, 2003||Sherwood Services Ag||Cluster ablation electrode system|
|US6605087 *||Jul 17, 2001||Aug 12, 2003||St. Jude Medical, Daig Division||Ablation catheter|
|US6616657 *||Sep 6, 2001||Sep 9, 2003||Cardiac Pacemakers, Inc.||RF ablation catheter tip electrode with multiple thermal sensors|
|US6658279 *||Nov 5, 2001||Dec 2, 2003||Ep Technologies, Inc.||Ablation and imaging catheter|
|US6669693 *||Nov 13, 2001||Dec 30, 2003||Mayo Foundation For Medical Education And Research||Tissue ablation device and methods of using|
|US6673290 *||Nov 12, 1998||Jan 6, 2004||Scimed Life Systems, Inc.||Electrode structure for heating and ablating tissue and method for making and assembling the same|
|US6805131 *||Aug 29, 2002||Oct 19, 2004||Ep Technologies, Inc.||Medical device with three dimensional collapsible basket structure|
|US6952615 *||Jun 18, 2002||Oct 4, 2005||Shutaro Satake||Radiofrequency thermal balloon catheter|
|US7048734 *||Sep 18, 1995||May 23, 2006||Ep Technologies, Inc.||Systems and methods for electronically altering the energy emitting characteristics of an electrode array to create different lesion patterns in body tissue|
|US8808161 *||Oct 23, 2003||Aug 19, 2014||Covidien Ag||Redundant temperature monitoring in electrosurgical systems for safety mitigation|
|US20010008967 *||Jan 10, 2001||Jul 19, 2001||Sherman Marshall L.||RF ablation apparatus and method using unipolar and bipolar techniques|
|US20020148476 *||Jun 7, 2002||Oct 17, 2002||Farley Brian E..||Method of ligating hollow anatomical structures|
|US20030018330 *||Aug 5, 2002||Jan 23, 2003||Swanson David K.||Systems and methods for creating long, thin lesions in body tissue|
|US20030125730 *||Jan 3, 2002||Jul 3, 2003||Afx Inc.||Flexible device for ablation of biological tissue|
|US20030216727 *||Mar 21, 2003||Nov 20, 2003||Long Gary L.||Medical device with improved wall construction|
|US20040015164 *||Jul 19, 2002||Jan 22, 2004||Fuimaono Kristine B.||Atrial ablation catheter and method for treating atrial fibrillation|
|US20040019349 *||Jul 23, 2002||Jan 29, 2004||Fuimaono Kristine B.||Ablation catheter having stabilizing array|
|US20040044270 *||May 28, 2003||Mar 4, 2004||Barry James P.||Articulating vertebrae with asymmetrical and variable radius of curvature|
|US20040133154 *||Dec 16, 2003||Jul 8, 2004||Flaherty J. Christopher||Systems and methods for delivering drugs to selected locations within the body|
|US20040143256 *||Aug 20, 2003||Jul 22, 2004||Bednarek Michael C.||Ablation catheter and electrode|
|US20040158141 *||Dec 31, 2003||Aug 12, 2004||Biosense Webster, Inc.||Catheter having circular ablation assembly|
|US20040181139 *||Apr 26, 2002||Sep 16, 2004||Falwell Gary S.||Method and apparatus for three dimensional mapping of electrical activity in blood vessels and ablation of electrical pathways identified by the three dimension map|
|US20040182384 *||Apr 5, 2004||Sep 23, 2004||Alfery David D.||Perilaryngeal oral airway with temperature sensor|
|US20040220625 *||Jan 16, 2004||Nov 4, 2004||Luigi Silvestri||Determining the presence and type of probe associated with an active implantable medical device, in particular a cardiac pacemaker|
|US20040230227 *||Feb 9, 2004||Nov 18, 2004||Zohar Avrahami||Handheld apparatus and method for transdermal drug delivery and analyte extraction|
|US20040260279 *||Jun 2, 2004||Dec 23, 2004||Gyrus Medical Limited||Electrosurgical generator and system|
|US20050010206 *||May 14, 2004||Jan 13, 2005||Cardima, Inc.||System and method for multi-channel RF energy delivery with coagulum reduction|
|US20050033315 *||Jul 29, 2004||Feb 10, 2005||Hankins Carol A.||Apparatus and method for guiding a medical device|
|US20050234439 *||Mar 25, 2005||Oct 20, 2005||Arthrocare Corporation||Method for treating obstructive sleep disorder includes removing tissue from base of tongue|
|US20060167448 *||Nov 17, 2003||Jul 27, 2006||Kozel Peter D||Electrophysiology catheter with ablation electrode|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US7751886 *||Jul 16, 2007||Jul 6, 2010||Pacesetter, Inc.||Guided atrial anti-tachycardia pacing for implanted cardiac stimulation|
|US7837679||Jul 17, 2006||Nov 23, 2010||Asthmatx, Inc.||Control system and process for application of energy to airway walls and other mediums|
|US7850685||Jun 20, 2006||Dec 14, 2010||Medtronic Ablation Frontiers Llc||Ablation catheter|
|US7853331||May 25, 2006||Dec 14, 2010||Asthmatx, Inc.||Medical device with procedure improvement features|
|US7854734||Jul 17, 2006||Dec 21, 2010||Asthmatx, Inc.||Control system and process for application of energy to airway walls and other mediums|
|US7857808||Jun 22, 2005||Dec 28, 2010||The Regents Of The University Of Michigan||Ablation catheters|
|US7860555||Oct 25, 2005||Dec 28, 2010||Voyage Medical, Inc.||Tissue visualization and manipulation system|
|US7860556||Nov 16, 2006||Dec 28, 2010||Voyage Medical, Inc.||Tissue imaging and extraction systems|
|US7918787||Mar 16, 2007||Apr 5, 2011||Voyage Medical, Inc.||Tissue visualization and manipulation systems|
|US7921855||Dec 11, 2006||Apr 12, 2011||Asthmatx, Inc.||Method for treating an asthma attack|
|US7930016||Nov 16, 2006||Apr 19, 2011||Voyage Medical, Inc.||Tissue closure system|
|US7931647||Oct 20, 2006||Apr 26, 2011||Asthmatx, Inc.||Method of delivering energy to a lung airway using markers|
|US7938123||Dec 1, 2008||May 10, 2011||Asthmatx, Inc.||Modification of airways by application of cryo energy|
|US7949407||Dec 29, 2006||May 24, 2011||Asthmatx, Inc.||Energy delivery devices and methods|
|US7992572||Nov 7, 2006||Aug 9, 2011||Asthmatx, Inc.||Methods of evaluating individuals having reversible obstructive pulmonary disease|
|US7993333 *||Jun 22, 2005||Aug 9, 2011||The Regents Of The University Of Michigan||Ablation catheters|
|US8050746||Jul 10, 2007||Nov 1, 2011||Voyage Medical, Inc.||Tissue visualization device and method variations|
|US8078266||Feb 5, 2008||Dec 13, 2011||Voyage Medical, Inc.||Flow reduction hood systems|
|US8131350||Dec 20, 2007||Mar 6, 2012||Voyage Medical, Inc.||Stabilization of visualization catheters|
|US8137333 *||Jul 25, 2007||Mar 20, 2012||Voyage Medical, Inc.||Delivery of biological compounds to ischemic and/or infarcted tissue|
|US8161978||Apr 24, 2012||Asthmatx, Inc.||Methods for treating asthma by damaging nerve tissue|
|US8181656||Feb 23, 2006||May 22, 2012||Asthmatx, Inc.||Methods for treating airways|
|US8197476||Oct 26, 2011||Jun 12, 2012||Hermes Innovations Llc||Tissue ablation systems|
|US8197477||Oct 26, 2011||Jun 12, 2012||Hermes Innovations Llc||Tissue ablation methods|
|US8221310||Aug 30, 2007||Jul 17, 2012||Voyage Medical, Inc.||Tissue visualization device and method variations|
|US8224416 *||May 9, 2008||Jul 17, 2012||St. Jude Medical, Atrial Fibrillation Division, Inc.||Basket catheter having multiple electrodes|
|US8235983||Jul 12, 2007||Aug 7, 2012||Asthmatx, Inc.||Systems and methods for delivering energy to passageways in a patient|
|US8235985||Sep 11, 2008||Aug 7, 2012||Voyage Medical, Inc.||Visualization and ablation system variations|
|US8251070||Apr 4, 2006||Aug 28, 2012||Asthmatx, Inc.||Methods for treating airways|
|US8257413||Sep 22, 2006||Sep 4, 2012||Asthmatx, Inc.||Modification of airways by application of energy|
|US8267094||Sep 18, 2012||Asthmatx, Inc.||Modification of airways by application of ultrasound energy|
|US8273084||Aug 25, 2008||Sep 25, 2012||Medtronic Ablation Frontiers Llc||Atrial ablation catheter and method of use|
|US8317744||Dec 31, 2008||Nov 27, 2012||St. Jude Medical, Atrial Fibrillation Division, Inc.||Robotic catheter manipulator assembly|
|US8317745||Dec 31, 2008||Nov 27, 2012||St. Jude Medical, Atrial Fibrillation Division, Inc.||Robotic catheter rotatable device cartridge|
|US8328802||Mar 13, 2009||Dec 11, 2012||Covidien Ag||Cordless medical cauterization and cutting device|
|US8333012||Oct 8, 2009||Dec 18, 2012||Voyage Medical, Inc.||Method of forming electrode placement and connection systems|
|US8337492||Nov 3, 2010||Dec 25, 2012||Medtronic Ablation Frontiers Llc||Ablation catheter|
|US8366706||Aug 15, 2008||Feb 5, 2013||Cardiodex, Ltd.||Systems and methods for puncture closure|
|US8372068||Aug 13, 2009||Feb 12, 2013||Hermes Innovations, LLC||Tissue ablation systems|
|US8372072||Nov 22, 2011||Feb 12, 2013||Cardiodex Ltd.||Methods and apparatus for hemostasis following arterial catheterization|
|US8377059||Mar 13, 2009||Feb 19, 2013||Covidien Ag||Cordless medical cauterization and cutting device|
|US8382753||Aug 13, 2009||Feb 26, 2013||Hermes Innovations, LLC||Tissue ablation methods|
|US8417321||Aug 24, 2011||Apr 9, 2013||Voyage Medical, Inc||Flow reduction hood systems|
|US8419613||Sep 13, 2011||Apr 16, 2013||Voyage Medical, Inc.||Tissue visualization device|
|US8435236||Nov 21, 2005||May 7, 2013||Cardiodex, Ltd.||Techniques for heat-treating varicose veins|
|US8443810||Jun 20, 2006||May 21, 2013||Asthmatx, Inc.||Methods of reducing mucus in airways|
|US8459268||Apr 24, 2012||Jun 11, 2013||Asthmatx, Inc.||Methods for treating airways|
|US8464723||Jun 28, 2011||Jun 18, 2013||Asthmatx, Inc.||Methods of evaluating individuals having reversible obstructive pulmonary disease|
|US8465486||Jun 18, 2013||Asthmatx, Inc.||Modification of airways by application of energy|
|US8480667||May 25, 2006||Jul 9, 2013||Asthmatx, Inc.||Medical device with procedure improvement features|
|US8483831||Feb 17, 2009||Jul 9, 2013||Holaira, Inc.||System and method for bronchial dilation|
|US8486063||Oct 3, 2008||Jul 16, 2013||Medtronic Ablation Frontiers Llc||Ablation catheter|
|US8489192||Jun 14, 2012||Jul 16, 2013||Holaira, Inc.||System and method for bronchial dilation|
|US8491581||Mar 13, 2009||Jul 23, 2013||Covidien Ag||Method for powering a surgical instrument|
|US8500732||Oct 26, 2009||Aug 6, 2013||Hermes Innovations Llc||Endometrial ablation devices and systems|
|US8529562||Nov 13, 2009||Sep 10, 2013||Minerva Surgical, Inc||Systems and methods for endometrial ablation|
|US8534291||May 31, 2006||Sep 17, 2013||Asthmatx, Inc.||Methods of treating inflammation in airways|
|US8538501||Jan 9, 2009||Sep 17, 2013||Mayo Foundation For Medical Education And Research||Mapping and ablation catheter system|
|US8540708||Oct 26, 2009||Sep 24, 2013||Hermes Innovations Llc||Endometrial ablation method|
|US8584681||Apr 22, 2010||Nov 19, 2013||Asthmatx, Inc.||Method for treating an asthma attack|
|US8617152||Jul 12, 2005||Dec 31, 2013||Medtronic Ablation Frontiers Llc||Ablation system with feedback|
|US8640711||Dec 9, 2010||Feb 4, 2014||Asthmatx, Inc.||Method for treating an asthma attack|
|US8641663||Mar 27, 2009||Feb 4, 2014||St. Jude Medical, Atrial Fibrillation Division, Inc.||Robotic catheter system input device|
|US8641664||Mar 27, 2009||Feb 4, 2014||St. Jude Medical, Atrial Fibrillation Division, Inc.||Robotic catheter system with dynamic response|
|US8641704||May 7, 2008||Feb 4, 2014||Medtronic Ablation Frontiers Llc||Ablation therapy system and method for treating continuous atrial fibrillation|
|US8657805||May 8, 2008||Feb 25, 2014||Intuitive Surgical Operations, Inc.||Complex shape steerable tissue visualization and manipulation catheter|
|US8657814||May 22, 2006||Feb 25, 2014||Medtronic Ablation Frontiers Llc||User interface for tissue ablation system|
|US8684962||Dec 31, 2008||Apr 1, 2014||St. Jude Medical, Atrial Fibrillation Division, Inc.||Robotic catheter device cartridge|
|US8690873||Jul 9, 2013||Apr 8, 2014||Hermes Innovations Llc||Endometrial ablation devices and systems|
|US8694071||Feb 11, 2011||Apr 8, 2014||Intuitive Surgical Operations, Inc.||Image stabilization techniques and methods|
|US8709008||May 9, 2008||Apr 29, 2014||Intuitive Surgical Operations, Inc.||Visual electrode ablation systems|
|US8715278||Nov 11, 2009||May 6, 2014||Minerva Surgical, Inc.||System for endometrial ablation utilizing radio frequency|
|US8731672||Jun 18, 2013||May 20, 2014||Holaira, Inc.||System and method for bronchial dilation|
|US8733367||Mar 28, 2013||May 27, 2014||Asthmatx, Inc.||Methods of treating inflammation in airways|
|US8740895||Jun 28, 2013||Jun 3, 2014||Holaira, Inc.||Delivery devices with coolable energy emitting assemblies|
|US8758229||Dec 20, 2007||Jun 24, 2014||Intuitive Surgical Operations, Inc.||Axial visualization systems|
|US8758342||Nov 27, 2008||Jun 24, 2014||Covidien Ag||Cordless power-assisted medical cauterization and cutting device|
|US8771267||Nov 15, 2012||Jul 8, 2014||Medtronic Ablation Frontiers Llc||Ablation catheter|
|US8771269||May 8, 2008||Jul 8, 2014||Medtronic Ablation Frontiers Llc||RF energy delivery system and method|
|US8777938 *||Jun 4, 2009||Jul 15, 2014||Wisconsin Alumni Research Foundation||Fan-beam microwave horn for bloodless resection|
|US8777943||Jun 28, 2013||Jul 15, 2014||Holaira, Inc.||Delivery devices with coolable energy emitting assemblies|
|US8794830||Oct 13, 2010||Aug 5, 2014||Biosense Webster, Inc.||Catheter with digitized temperature measurement in control handle|
|US8808280||Apr 20, 2012||Aug 19, 2014||Holaira, Inc.||Systems, assemblies, and methods for treating a bronchial tree|
|US8814845||Feb 3, 2012||Aug 26, 2014||Intuitive Surgical Operations, Inc.||Delivery of biological compounds to ischemic and/or infarcted tissue|
|US8821486||Nov 11, 2010||Sep 2, 2014||Hermes Innovations, LLC||Tissue ablation systems and methods|
|US8821489||Apr 20, 2012||Sep 2, 2014||Holaira, Inc.||Systems, assemblies, and methods for treating a bronchial tree|
|US8834461||Jul 11, 2006||Sep 16, 2014||Medtronic Ablation Frontiers Llc||Low power tissue ablation system|
|US8858609||Feb 6, 2009||Oct 14, 2014||Intuitive Surgical Operations, Inc.||Stent delivery under direct visualization|
|US8880185||Jun 25, 2013||Nov 4, 2014||Boston Scientific Scimed, Inc.||Renal denervation and stimulation employing wireless vascular energy transfer arrangement|
|US8888769||Nov 11, 2010||Nov 18, 2014||Asthmatx, Inc.||Control system and process for application of energy to airway walls and other mediums|
|US8906011||Nov 16, 2007||Dec 9, 2014||Kardium Inc.||Medical device for use in bodily lumens, for example an atrium|
|US8911439||Nov 11, 2010||Dec 16, 2014||Holaira, Inc.||Non-invasive and minimally invasive denervation methods and systems for performing the same|
|US8920411||Jun 28, 2006||Dec 30, 2014||Kardium Inc.||Apparatus and method for intra-cardiac mapping and ablation|
|US8920413||May 25, 2006||Dec 30, 2014||Asthmatx, Inc.||Energy delivery devices and methods|
|US8932287||Mar 23, 2011||Jan 13, 2015||Kardium Inc.||Medical device for use in bodily lumens, for example an atrium|
|US8932289||Sep 26, 2011||Jan 13, 2015||Holaira, Inc.||Delivery devices with coolable energy emitting assemblies|
|US8934962||Aug 31, 2007||Jan 13, 2015||Intuitive Surgical Operations, Inc.||Electrophysiology mapping and visualization system|
|US8939970||Feb 29, 2012||Jan 27, 2015||Vessix Vascular, Inc.||Tuned RF energy and electrical tissue characterization for selective treatment of target tissues|
|US8944071||Aug 20, 2012||Feb 3, 2015||Asthmatx, Inc.||Method for treating an asthma attack|
|US8951251||Nov 7, 2012||Feb 10, 2015||Boston Scientific Scimed, Inc.||Ostial renal nerve ablation|
|US8956348||Jul 20, 2011||Feb 17, 2015||Minerva Surgical, Inc.||Methods and systems for endometrial ablation|
|US8961504 *||Apr 9, 2010||Feb 24, 2015||Covidien Lp||Optical hydrology arrays and system and method for monitoring water displacement during treatment of patient tissue|
|US8961507||Apr 20, 2012||Feb 24, 2015||Holaira, Inc.||Systems, assemblies, and methods for treating a bronchial tree|
|US8961508||Apr 20, 2012||Feb 24, 2015||Holaira, Inc.||Systems, assemblies, and methods for treating a bronchial tree|
|US8974451||Oct 25, 2011||Mar 10, 2015||Boston Scientific Scimed, Inc.||Renal nerve ablation using conductive fluid jet and RF energy|
|US8979841||Jun 10, 2014||Mar 17, 2015||Medtronic Ablation Frontiers Llc||Ablation catheter|
|US8996091||Nov 15, 2013||Mar 31, 2015||St. Jude Medical, Atrial Fibrillation Division, Inc.||Basket catheter having multiple electrodes|
|US8998901||Aug 23, 2013||Apr 7, 2015||Hermes Innovations Llc||Endometrial ablation method|
|US9005194 *||Jul 18, 2008||Apr 14, 2015||Medtronic Ablation Frontiers Llc||Atrial ablation catheter adapted for treatment of septal wall arrhythmogenic foci and method of use|
|US9005195||Sep 26, 2011||Apr 14, 2015||Holaira, Inc.||Delivery devices with coolable energy emitting assemblies|
|US9011423||Mar 11, 2013||Apr 21, 2015||Kardium, Inc.||Systems and methods for selecting, activating, or selecting and activating transducers|
|US9017320||Mar 11, 2013||Apr 28, 2015||Kardium, Inc.||Systems and methods for activating transducers|
|US9017321||Mar 11, 2013||Apr 28, 2015||Kardium, Inc.||Systems and methods for activating transducers|
|US9017324||Jun 28, 2013||Apr 28, 2015||Holaira, Inc.||Delivery devices with coolable energy emitting assemblies|
|US9023034||Nov 22, 2011||May 5, 2015||Boston Scientific Scimed, Inc.||Renal ablation electrode with force-activatable conduction apparatus|
|US9027564||May 10, 2013||May 12, 2015||Asthmatx, Inc.||Method for treating a lung|
|US9028472||Dec 21, 2012||May 12, 2015||Vessix Vascular, Inc.||Methods and apparatuses for remodeling tissue of or adjacent to a body passage|
|US9028485||Sep 23, 2011||May 12, 2015||Boston Scientific Scimed, Inc.||Self-expanding cooling electrode for renal nerve ablation|
|US9033976||May 16, 2013||May 19, 2015||Asthmatx, Inc.||Modification of airways by application of energy|
|US9037259||Dec 21, 2012||May 19, 2015||Vessix Vascular, Inc.||Methods and apparatuses for remodeling tissue of or adjacent to a body passage|
|US9044254||Mar 15, 2013||Jun 2, 2015||Covidien Lp||Microwave ablation catheter and method of utilizing the same|
|US9050098||Nov 13, 2008||Jun 9, 2015||Covidien Ag||Cordless medical cauterization and cutting device|
|US9050106||Dec 21, 2012||Jun 9, 2015||Boston Scientific Scimed, Inc.||Off-wall electrode device and methods for nerve modulation|
|US9055906||May 12, 2010||Jun 16, 2015||Intuitive Surgical Operations, Inc.||In-vivo visualization systems|
|US9060761||Nov 9, 2011||Jun 23, 2015||Boston Scientific Scime, Inc.||Catheter-focused magnetic field induced renal nerve ablation|
|US9072902||Dec 21, 2012||Jul 7, 2015||Vessix Vascular, Inc.||Methods and apparatuses for remodeling tissue of or adjacent to a body passage|
|US9079000||Oct 16, 2012||Jul 14, 2015||Boston Scientific Scimed, Inc.||Integrated crossing balloon catheter|
|US9084609||Jul 18, 2011||Jul 21, 2015||Boston Scientific Scime, Inc.||Spiral balloon catheter for renal nerve ablation|
|US9089350||Nov 9, 2011||Jul 28, 2015||Boston Scientific Scimed, Inc.||Renal denervation catheter with RF electrode and integral contrast dye injection arrangement|
|US9101735||Jul 7, 2009||Aug 11, 2015||Intuitive Surgical Operations, Inc.||Catheter control systems|
|US9119600||Nov 15, 2012||Sep 1, 2015||Boston Scientific Scimed, Inc.||Device and methods for renal nerve modulation monitoring|
|US9119632||Nov 16, 2012||Sep 1, 2015||Boston Scientific Scimed, Inc.||Deflectable renal nerve ablation catheter|
|US9119633||Mar 5, 2013||Sep 1, 2015||Kardium Inc.||Apparatus and method for intra-cardiac mapping and ablation|
|US9119634||Nov 18, 2014||Sep 1, 2015||Kardium Inc.||Apparatus and method for intra-cardiac mapping and ablation|
|US9121774||Jun 21, 2013||Sep 1, 2015||Covidien Lp||Microwave thermometry for microwave ablation systems|
|US9125643||Apr 30, 2014||Sep 8, 2015||Holaira, Inc.||System and method for bronchial dilation|
|US9125666||Sep 28, 2007||Sep 8, 2015||Vessix Vascular, Inc.||Selectable eccentric remodeling and/or ablation of atherosclerotic material|
|US9125667||Oct 18, 2007||Sep 8, 2015||Vessix Vascular, Inc.||System for inducing desirable temperature effects on body tissue|
|US9127989||Jun 21, 2013||Sep 8, 2015||Covidien Lp||Microwave thermometry for microwave ablation systems|
|US20050033137 *||Jun 14, 2004||Feb 10, 2005||The Regents Of The University Of Michigan||Ablation catheters and methods for their use|
|US20050240176 *||Jun 22, 2005||Oct 27, 2005||Regents Of The University Of Michigan||Ablation catheters|
|US20050251132 *||Jun 22, 2005||Nov 10, 2005||Regents Of The University Of Michigan||Ablation catheters|
|US20060111700 *||Nov 24, 2004||May 25, 2006||Ablation Frontiers, Inc.||Atrial ablation catheter and method of use|
|US20060111701 *||Nov 24, 2004||May 25, 2006||Ablation Frontiers, Inc.||Atrial ablation catheter adapted for treatment of septal wall arrhythmogenic foci and method of use|
|US20060137698 *||Feb 23, 2006||Jun 29, 2006||Asthmatx, Inc.||Methods for treating airways|
|US20060247617 *||May 25, 2006||Nov 2, 2006||Asthmatx, Inc.||Energy delivery devices and methods|
|US20060247618 *||May 25, 2006||Nov 2, 2006||Asthmatx, Inc.||Medical device with procedure improvement features|
|US20060247619 *||May 25, 2006||Nov 2, 2006||Asthmatx, Inc.||Medical device with procedure improvement features|
|US20070083193 *||May 22, 2006||Apr 12, 2007||Werneth Randell L||User interface for tissue ablation system|
|US20070083194 *||Jun 20, 2006||Apr 12, 2007||Kunis Christopher G||Ablation catheter|
|US20070093802 *||Oct 21, 2005||Apr 26, 2007||Danek Christopher J||Energy delivery devices and methods|
|US20080275443 *||Jul 18, 2008||Nov 6, 2008||Hakan Oral||Atrial ablation catheter adapted for treatment of septal wall arrhythmogenic foci and method of use|
|US20090326511 *||Dec 31, 2009||Kalyanam Shivkumar||Method to protect the esophagus and other mediastinal structures during cardiac and thoracic interventions|
|US20100076426 *||May 9, 2008||Mar 25, 2010||De La Rama Alan||Basket catheter having multiple electrodes|
|US20100312234 *||Jun 4, 2009||Dec 9, 2010||Mahvi David M||Fan-beam microwave horn for bloodless resection|
|US20110019893 *||Jul 21, 2010||Jan 27, 2011||Norbert Rahn||Method and Device for Controlling the Ablation Energy for Performing an Electrophysiological Catheter Application|
|US20110238058 *||Sep 29, 2011||Estech, Inc. (Endoscopic Technologies, Inc.)||Indifferent electrode pad systems and methods for tissue ablation|
|US20110251605 *||Apr 9, 2010||Oct 13, 2011||Tyco Healthcare Group Lp||Optical Hydrology Arrays and System and Method for Monitoring Water Displacement During Treatment of Patient Tissue|
|US20120136280 *||Feb 9, 2012||May 31, 2012||Syneron Medical Ltd.||Method and apparatus for treatment of adipose tissue|
|US20120289951 *||May 14, 2012||Nov 15, 2012||Kassab Ghassan S||Systems and methods for cryoblation of a tissue|
|EP2441408A1 *||Oct 12, 2011||Apr 18, 2012||Biosense Webster, Inc.||Catheter with digitized temperature measurement in control handle|
|EP2490764A2 *||Oct 20, 2010||Aug 29, 2012||Thomas J. Wolfe||Electromagnetic thrombus treatment system and method|
|WO2007149970A2 *||Jun 21, 2007||Dec 27, 2007||St Jude Medical Atrial Fibrill||Apparatus and method for ablating tissue|
|WO2009089415A1 *||Jan 9, 2009||Jul 16, 2009||Samuel J Asirvatham||Mapping and ablation catheter system|
|WO2009120944A2 *||Mar 27, 2009||Oct 1, 2009||St. Jude Medical, Atrial Fibrillation Division, Inc.||Robotic catheter manipulator assembly|
|WO2013040160A1 *||Sep 13, 2012||Mar 21, 2013||Pigott John P||Intravascular catheter having an expandable incising portion|
|WO2014025553A1 *||Jul 26, 2013||Feb 13, 2014||Covidien Lp||Microwave ablation catheter and method of utilizing the same|
|Cooperative Classification||A61B18/18, A61B18/1492, A61B2018/00291, A61B2018/0016, A61B2018/00351, A61B2017/00482, A61B18/16, A61B2018/1467, A61B2018/00214|
|Jan 3, 2006||AS||Assignment|
Owner name: ABLATION FRONTIERS, INC., CALIFORNIA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:WERNETH, RANDELL L.;SHERMAN, MARSHALL L.;CASTELLANO, THOMAS M.;AND OTHERS;REEL/FRAME:017424/0073;SIGNING DATES FROM 20050920 TO 20050923
|Jun 16, 2009||AS||Assignment|
Owner name: MEDTRONIC ABLATION FRONTIERS TECHNOLOGIES, LLC, MI
Free format text: CHANGE OF NAME;ASSIGNOR:MEDTRONIC ABLATION FRONTIERS, INC.;REEL/FRAME:022824/0856
Effective date: 20090327
Owner name: MEDTRONIC ABLATION FRONTIERS, LLC, MINNESOTA
Free format text: CHANGE OF NAME;ASSIGNOR:MEDTRONIC ABLATION FRONTIERS TECHNOLOGIES, LLC;REEL/FRAME:022824/0893
Effective date: 20090417
Owner name: MEDTRONIC ABLATION FRONTIERS, INC., MINNESOTA
Free format text: MERGER;ASSIGNOR:ABLATION FRONTIERS, INC.;REEL/FRAME:022824/0760
Effective date: 20090205