DUAL MODE LESION FORMATION APPARATUS, SYSTEMS AND METHODS
A dual mode lesion formation apparatus including a probe component and clamp component.
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This application is a continuation-in-part of co-pending U.S. application Ser. No. 11/067,535, filed Feb. 25, 2005, which is incorporated herein by reference.
BACKGROUND OF THE INVENTIONS1. Field of Inventions
The present inventions relate generally to devices for performing therapeutic operations on body tissue.
2. Description of the Related Art
There are many instances where electrosurgical devices are used to form therapeutic lesions in tissue. Therapeutic lesions are frequently formed to treat conditions in the heart, prostate, liver, brain, gall bladder, uterus, breasts, lungs and other solid organs. Electromagnetic radio frequency (“RF”) may, for example, be used to heat and eventually kill (i.e. “ablate”) tissue to form a lesion. During the ablation of soft tissue (i.e. tissue other than blood, bone and connective tissue), tissue coagulation occurs and it is the coagulation that kills the tissue. Thus, references to the ablation of soft tissue are necessarily references to soft tissue coagulation. “Tissue coagulation” is the process of cross-linking proteins in tissue to cause the tissue to jell. In soft tissue, it is the fluid within the tissue cell membranes that jells to kill the cells, thereby killing the tissue.
The tissue coagulation energy is typically supplied by an electrosurgical unit (“ESU”) during the therapeutic procedure. More specifically, after a catheter, surgical probe or clamp has been connected to the ESU, and the electrodes or other energy transmission elements on the catheter, surgical probe or clamp have been positioned adjacent to the target tissue, energy from the ESU is transmitted through the energy transmission elements to the tissue to from a lesion. The amount of power required to coagulate tissue ranges from 5 to 150 W.
Some electrosurgical procedures require the use of more than one electrosurgical device. One example of such a procedure involves the formation of therapeutic lesions to treat cardiac conditions such as atrial fibrillation. Here, a clamp may be used to create a first transmural epicardial lesion around the right pulmonary vein pair and a second transmural epicardial lesion around the left pulmonary vein pair. Thereafter, if needed, a surgical probe may be used to create a linear transmural epicardial lesion between the right and left pulmonary vein pairs. A linear transmural lesion that extends from the lesion between the right and left pulmonary vein pairs to the left atrial appendage may also be created.
The present inventors have determined that conventional lesion formation devices are susceptible to improvement. For example, the present inventors have determined that there may be more efficient and cost effective ways, in terms of materials, manufacturing, sterilization, shipping, etc., to provide physicians with the capabilities of two separate devices, such as the aforementioned separate clamp and surgical probe.
SUMMARY OF THE INVENTIONSA dual mode apparatus in accordance with one invention herein includes a probe component, a clamp component configured to be mounted on a clamp member, a first electrical connector and a second electrical connector. The first electrical connector is operably connected to the probe component and the second electrical connector is operably connected to the probe component and to the clamp component. A system in accordance with a present invention includes the dual mode apparatus and a source of tissue coagulation and/or a clamp. A method of forming a lesion with the dual mode apparatus includes connecting one of the electrical connectors to a source of tissue coagulation energy and transmitting the tissue coagulation energy to the tissue with the probe component.
A method in accordance with a present invention includes supplying tissue coagulation energy to the first side of the tissue structure and discontinuing the supply of tissue coagulation energy to the first side of the tissue structure when a predetermined temperature is measured on the second side of the tissue structure.
Detailed description of embodiments of the inventions will be made with reference to the accompanying drawings.
The following is a detailed description of the best presently known modes of carrying out the inventions. This description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the inventions.
The detailed description of the preferred embodiments is organized as follows:
I. Introduction
II. Exemplary Dual Mode Lesion Formation Apparatus
III. Exemplary Systems
IV. Exemplary Methods
The section titles and overall organization of the present detailed description are for the purpose of convenience only and are not intended to limit the present inventions.
I. IntroductionThis specification discloses a number of structures, mainly in the context of cardiac treatment, because the structures are well suited for use with myocardial tissue. Nevertheless, it should be appreciated that the structures are applicable for use in therapies involving other types of soft tissue. For example, various aspects of the present inventions have applications in procedures concerning other regions of the body such as the prostate, liver, brain, gall bladder, uterus, breasts, lungs, and other solid organs.
II. Exemplary Dual Mode Lesion Formation ApparatusA dual mode lesion formation apparatus in accordance with one embodiment of a present invention is generally represented by reference numeral 10 in
There are a variety of advantages associated with such a device. By way of example, but not limitation, a large portion of the expense associated with the manufacture of electrosurgical probes and clamps is associated with the electrode and temperature sensor segments of the assembly process. The present inventions significantly reduce these assembly related expenses because the electrodes and temperature sensors on the surgical probe component are used in both the probe mode of operation and the clamp mode of operation, thereby eliminating the need to separately assemble electrodes and temperature sensors on a surgical probe as well as on a separate electrosurgical clamp. The sterilization, packaging and shipment of the present dual mode lesion formation apparatus may also be accomplished in a manner that is more efficient than the sterilization, packaging and shipment of separate devices.
Referring to
In the exemplary implementation illustrated in
The exemplary surgical probe component 100 is a fluid cooled surgical probe and, as illustrated in
In addition to the aforementioned fillers, heat transfer may be promoted by minimizing the thickness of the electrically non-conductive material between the lumens 122 and 124 and the electrodes 106 and by maximizing the cross-sectional area of the inlet and outlet lumens. With respect to the outer structure 118 illustrated in
Suitable materials for the malleable hypotube 110 include annealed stainless steel, while the suitable material for the mandrel 116 includes annealed stainless steel and beryllium copper.
As illustrated for example in
The electrodes 106 in the exemplary probe component 100 illustrated in
With respect to materials, the electrodes 106 are preferably in the form of wound, spiral closed coils. The coils are made of electrically conducting material, like copper alloy, platinum, or stainless steel, or compositions such as drawn-filled tubing (e.g. a copper core with a platinum jacket). The electrically conducting material of the coils can be further coated with platinum-iridium or gold to improve its conduction properties and biocompatibility. Preferred coil electrodes are disclosed in U.S. Pat. Nos. 5,797,905 and 6,245,068.
Alternatively, the electrodes 106 may be in the form of solid rings of conductive material, like platinum, or can comprise a conductive material, like platinum-iridium or gold, coated upon the device using conventional coating techniques or an ion beam assisted deposition (IBAD) process. For better adherence, an undercoating of nickel, silver or titanium can be applied. The electrodes can also be in the form of helical ribbons. The electrodes can also be formed with a conductive ink compound that is pad printed onto a non-conductive tubular body. A preferred conductive ink compound is a silver-based flexible adhesive conductive ink (polyurethane binder), however other metal-based adhesive conductive inks such as platinum-based, gold-based, copper-based, etc., may also be used to form electrodes. Such inks are more flexible than epoxy-based inks. Open coil electrodes may also be employed. Still other types of electrodes are formed from electroless plated copper on a polyimide film or tubular substrate. Gold, nickel or silver should be plated over the copper for electrochemical stability and improved biocompatibility. The plating can be applied in continuous form (up to about 1-2 cm in length at most) or can be applied in a pattern that is designed to improve current density distributions and/or electrode flexing characteristics. Temperature sensors (e.g. thermocouples) may be incorporated into the electrode structure by placing the temperature sensors in a channel in the polyimide film or tubular substrate and then plating over them.
The exemplary flexible electrodes 106 are preferably about 4 mm to about 20 mm in length. In the illustrated embodiments, the electrodes 106 are 15 mm in length with 2 mm spacing, which will result in the creation of continuous lesion patterns in tissue when coagulation energy is applied simultaneously to adjacent electrodes. For rigid electrodes, the length of the each electrode can vary from about 2 mm to about 10 mm. Using multiple rigid electrodes longer than about 10 mm each adversely effects the overall flexibility of the device, while electrodes having lengths of less than about 2 mm do not consistently form the desired continuous lesion patterns. Additionally, although the illustrated embodiments include four (4) electrodes, the number of electrodes or other energy transmission elements may be varied to suit particular applications. For example, it may be desirable to provide a seven (7) electrode surgical probe component so that longer lesions can be formed probe mode. The proximal three (3) electrodes would typically not be aligned with the probe support 200 or used in clamp mode.
In some implementations, the electrodes 106 may be covered with a wettable fluid retention element that is saturated with ionic fluid (such as saline) prior to use. Suitable materials for the fluid retention element include biocompatible fabrics commonly used for vascular patches (such as woven Dacron®), open cell foam materials, hydrogels, nanoporous balloon materials (with very slow fluid delivery to the surface), and hydrophilic nanoporous materials. The effective electrical resistivity of the fluid retention element when wetted with 0.9% saline (normal saline) should range from about 1 Ω-cm to about 2000 Ω-cm. A preferred resistivity for epicardial and endocardial procedures is about 1000 Ω-cm.
Other types of energy transmission elements may be carried by the surgical probe component for the purpose of forming lesions in tissue. For example, infrared lasers, focused and unfocused ultrasonic transducers, microwave electrodes, ohmically heated hot wires, and the like may be substituted for the exemplary electrodes 106.
Additional details concerning fluid cooled surgical probes similar to that described above are presented in U.S. Patent App. Pub. No. 2003/0078644, which is entitled “Apparatus for Supporting Diagnostic and Therapeutic Elements in Contact With Tissue Including Dual Lumen Cooling Device” and incorporated herein by reference.
Although the exemplary surgical probe component 100 is an internally cooled, fluid cooled surgical probe, the present inventions are not limited to such probes. Other exemplary surgical probes include, for example, externally cooled, fluid cooled surgical probes such as those illustrated in U.S. Patent App. Pub. No. 2003/0014048, which is entitled “Fluid Cooled Apparatus for Supporting Diagnostic and Therapeutic Elements in Contact with Tissue” and non-cooled surgical probes such as those illustrated in U.S. Pat. Nos. 6,142,994 and 6,645,200. The exemplary surgical probe component 100 may also be replaced with a catheter probe component in those instances where percutaneous access (e.g. access through the femoral vein to a chamber within the heart) is desired. Suitable catheters are disclosed in U.S. Pat. Nos. 6,013,052, 6,203,525, 6,214,002 and 6,241,754. The U.S. patents and published applications mentioned in this paragraph are incorporated herein by reference.
Turning to the exemplary probe support 200, the probe support may be used to removably secure the distal portion of the surgical probe component 100 (or other lesion formation device) onto one of the clamp members of a clamp. As used herein, the term “clamp” includes, but is not limited to, clamps, clips, forceps, hemostats, and any other surgical device that includes a pair of opposable clamp members that hold tissue, at least one of which is movable relative to the other. In some instances, the clamp members are connected to a scissors-like arrangement including a pair of handle supporting arms that are pivotably connected to one another. The clamp members are secured to one end of the arms and the handles are secured to the other end. Certain clamps that are particularly useful in minimally invasive procedures also include a pair of handles and a pair of clamp members. Here, however, the clamp members and handles are not mounted on the opposite ends of the same arm. Instead, the handles are carried by one end of an elongate housing and the clamp members are carried by the other. A suitable mechanical linkage located within the housing causes the clamp members to move relative to one another in response to movement of the handles. The clamp members may be linear or have a predefined curvature that is optimized for a particular surgical procedure or portion thereof. The clamp members may also be rigid or malleable.
One example of a clamp to which the clamp component 200 may be secured is generally represented by reference numeral 300 in
As illustrated for example in
The exemplary base member 202 is preferably formed from a soft, resilient, low durometer material that is electrically insulating. Suitable materials include polyurethane, silicone and polyurethane/silicone blends having a hardness of between about 20 Shore D and about 72 Shore D. In the illustrated embodiment, the base member 202 and connector 206 are an integral structure and the connector is formed from the same material as the base member. Alternatively, the base member 202 and connector 206 may be separate structural elements that are secured to one another. Here, the connector 206 would typically be formed from a harder material than the base member 202. The length of the probe support 200 will vary according to the intended application. In the area of cardiovascular treatments, it is anticipated that suitable lengths will range from, but are not limited to, about 4 cm to about 10 cm. In the exemplary implementation, the probe support 200 about 6 cm in length.
It should also be noted that the present inventions are not limited to the exemplary probe support 200 illustrated in
Referring to
The temperature sensors 222 in the illustrated embodiment are carried on a tubular structure 224 that includes a linear channel 226. The linear channel 226 insures that the temperature sensors 222 will all face in the same direction (e.g. facing tissue) and be arranged in linear fashion. The temperature sensors 222 are connected to signal wires 228, which pass through the tubular structure 224, a cable 230 (note
The temperature sensors 222 and tubular structure 224 may be secured to a clamp member in substantially the same manner as the surgical probe distal portion 114 and electrodes 106. To that end, the clamp component 220 is provided with a base member 234, which has a slot 236, and a connector 238. The size and shape of the slot 236 will, of course, depend on the size and shape of the structure that it is holding. The tubular structure 224 is cylindrical in shape and, according, the exemplary slot 236 has a corresponding arcuate cross-sectional shape. The arc is preferably slightly greater than 180 degrees so that the base member 234 will deflect when a probe is inserted into the slot 236 and then snap back to hold the probe in place. So configured, slightly less than one-half (i.e. about 160° of the 360° circumference) of the surface of the tubular structure when it is held within the slot 236. Adhesive may also be used to hold the tubular structure 224 in place. The exemplary connector 238 is configured to removably mate with the clamp member slot 318 (
With respect to dimensions and materials, the tubular structure 224 may be a flexible structure with an outer diameter that is typically between about 1.5 mm and about 3 mm. Suitable support structure materials include, for example, flexible biocompatible thermoplastic tubing such as unbraided Pebax® material, polyethylene, or polyurethane tubing. The exemplary base member 234 is preferably formed from a soft, resilient, low durometer material that is electrically insulating. Suitable materials include polyurethane, silicone and polyurethane/silicone blends having a hardness of between about 20 Shore D and about 72 Shore D. In the illustrated embodiment, the base member 234 and connector 238 are an integral structure and the connector is formed from the same material as the base member. Alternatively, the base member 234 and connector 238 may be separate structural elements that are secured to one another. Here, the connector 238 would typically be formed from a harder material than the base member 234. The length of the base member 234 will vary according to the intended application. In the area of cardiovascular treatments, it is anticipated that suitable lengths will range from, but are not limited to, about 4 cm to about 10 cm. In the exemplary implementation, the base member 234 about 6 cm in length.
It should also be noted that the present inventions are not limited to the exemplary clamp component 220 illustrated in
The exemplary dual mode lesion formation apparatus 10 and clamp 300 are preferably configured such that the electrodes 106 will be parallel to, and relatively close to the tubular structure 224 (i.e. a spacing of about 1-10 mm), when the clamp 300 is in the closed orientation. Such an arrangement will allow the lesion formation apparatus and clamp to grip a bodily structure without cutting through the structure. The configuration of the lesion formation apparatus 10 and clamp 300 may, however, vary from application to application to suit particular situations.
Turning to
As noted above, the surgical probe component electrodes 106 and temperature sensors 150 and the clamp component temperature sensors 222 on the exemplary dual mode lesion formation apparatus 10 are connected to a pair of electrical connectors in such a manner that one of the connectors will be used to connect to the lesion formation apparatus 10 to an ESU during the probe mode of operation and the other connector will be used to connect the lesion formation apparatus to the ESU during the clamp mode of operation. To that end, and referring first to
Turning to
In some implementations, each of the electrical connector (e.g. PC boards) 158 and 160 are provided with electronic codes that tell ESU which mode of operation is the desired mode of operation. Accordingly, the electrical connector 158 will include electronic codes indicative of the probe mode and the electrical connector 160 will include electronic codes indicative of the clamp mode.
Dual mode lesion formation apparatus in accordance with the present inventions may also be provided with stimulation electrodes that are used to stimulate tissue (such as by pacing). For example, the exemplary dual mode lesion formation apparatus 10b illustrated in
The tissue stimulation electrodes 166 and 168, which are respectively carried on the distal ends of the surgical probe component 100b and the clamp component 220b in the illustrated embodiment, are connected to signal wires 170 and 172. The signal wire 170 extends through the surgical probe component signal wire lumen 128 and signal wire tube 154, as well as through the proximal end of the handle 104, to a connector 174. To that end, the tip member 120b, which is otherwise identical to the tip member 120, is modified so that it can support the tissue stimulation electrode 166 and includes an aperture (not shown) that allows the signal wire 170 to pass from the electrode to the signal wire lumen 128. The tissue stimulation electrode 168 is mounted on the distal end of the tubular structure 224 in place of the tip member 232 and the signal wire 172 passes through the tubular structure and the cable 230, as well as through the proximal end of the handle 104, to a connector 176. The connectors 174 and 176 may be connected to a conventional pacing apparatus, or to an ECG machine that is capable of monitoring and recording electrical impulses, as is describe in greater detail in Sections III and IV below.
Minor adjustments (as compared to the dual mode lesion apparatus 10) may also be made so that the tissue stimulation electrodes 166 and 168 will be located distal of the distal ends of the associated clamp members (
Tissue stimulation electrodes 166 and 168 may also be added to the surgical probe 100 and the clamp member 220a on the dual mode lesion formation apparatus 10a. The resulting dual mode lesion formation apparatus (not shown) would be essentially identical to the apparatus 10b but for the use of the clamp member 220a and its associated wiring for the electrode 244.
Alternatively, or additionally, tissue stimulation electrodes (not shown) may be provided on a surgical probe component between the electrodes 106, proximal of the proximal-most electrode 106 and distal of the distal-most electrode 106. Such stimulation electrodes may be used to determine the depth of a lesion formed by the electrodes 106 and, correspondingly, whether or not a lesion is transmural at various points along the length of the lesion. Stimulation energy may be used to determine lesion depth because non-viable tissue (e.g. coagulated tissue) cannot be stimulated and will not propagate stimulation energy to nearby tissue. As such, when the application of stimulation energy that should stimulate tissue at a known depth fails to do so, and that depth is greater than or equal to the thickness of the body structure, it may be inferred that a transmural lesion has been formed.
Additional information concerning tissue stimulation electrodes, as well as the manner in which they may be employed in conjunction with a surgical probe and a clamp based device, is provided in U.S. application Ser. No. 10/727,143, which is entitled “Surgical Methods And Apparatus For Forming Lesions In Tissue And Confirming Whether A Therapeutic Lesion Has Been Formed” and incorporated herein by reference.
III. Exemplary SystemsA tissue coagulation system 1000 in accordance with one embodiment of a present invention is illustrated in
The fluid supply and control apparatus 400, which may be used to supply cooling fluid to the surgical probe component 100, includes housing 402, a fluid outlet port 404, and a fluid inlet port 406. The fluid outlet port 404 may be coupled to the stopcock or other connector associated with the infusion tube 134 (and, therefore, to the inlet lumen 122) by a connector tube 408, while the fluid inlet port 406 may be coupled to the stopcock or other connector associated with the ventilation tube 140 (and, therefore, to the outlet lumen 124) by a connector tube 410. An infusion pump capable of variable flow rates is one example of a suitable fluid supply and control apparatus. The cooling fluid is not limited to any particular fluid. Preferably, however, the fluid will be a low or electrically non-conductive fluid such as sterile water or 0.9% saline solution. A suitable fluid inlet temperature is about 0 to 25° C. and the fluid supply and control apparatus 400 may be provided with a suitable cooling system, if desired, to bring the temperature of the fluid down to the desired level. In a four electrode embodiment where 150 W is being supplied to the electrodes 106, for example, a suitable constant fluid flow rate is about 5 ml/min to about 20 ml/min.
The power supply and control apparatus 420 includes an electrosurgical unit (“ESU”) 422 that supplies and controls RF power. A suitable ESU is the Model 4810A ESU sold by Boston Scientific Corporation of Natick, Mass., which is capable of supplying and controlling power on an electrode-by-electrode basis. This is sometimes referred to as “multi-channel control.” Typically, power to the surgical probe component 100 will typically be controlled as a function of the temperature at each electrode 106 in order to insure that tissue is coagulated without over-heating and causing coagulum and charring. With respect to temperature sensing at the surgical probe component electrodes 106, temperature is measured by the aforementioned temperatures sensors 150. Alternatively, in those instances where temperature sensors are not employed, the respective temperatures at each electrode 106 may be determined by measuring impedance at each electrode. In either case, the ESU 422 preferably controls power to the electrodes 106 as a function of temperature in both the probe mode of operation and the clamp mode of operation. The temperature of tissue adjacent to the clamp component 220 is measured by the temperature sensors 222.
In addition to the temperatures measured at the electrodes 106, the ESU 422 may also be used to control power to the electrodes as a function of the temperature measured by the clamp component temperature sensors 222 in the clamp mode of operation. An inventor herein has determined that temperature on the side of the target tissue structure opposite an energy transmission element (e.g. the electrodes 106) is indicative of lesion transmurality (i.e. whether or not a lesion that extends from one side of the target tissue structure to the other has been formed). More specifically, the inventor herein has determined that measured temperatures of about 50° C. to about 60° C. on the side of the tissue structure opposite the side that is in contact with surgical probe electrodes 106 for at least 1 second are indicative of the formation of a transmural lesion. The power supply and control apparatus 420 may, therefore, be configured to discontinue energy transmission when a predetermined temperature (e.g. a temperature between about 50° C. and about 60° C.) is measured by the temperature sensors 222 for at least 3 seconds. Alternatively, or in addition, the power supply and control apparatus 420 may also be configured to provide an audible or visible indication that the predetermined temperature has been measured for a predetermined period.
The ESU 422 transmits energy to the electrodes 106 by way of a cable 424. The cable 424 includes a connector 426, which may be individually connected to either the electrical connector 158 (in the probe mode) or the electrical connector 160 (in the clamp mode). As noted above, the surgical probe component power and signal wires 148 and 156 are connected to electrical connector 158 and to electrical connector 160. The clamp component signal wires 228, on the other hand, are only connected to the electrical connector 160. The cable 424 also includes a connector 428, which may be connected to a power output port 430 on the ESU 422.
The power and signal wires 148, 156 and 228 should be connected to the electrical connectors 158 and 160 in such a manner that the physician will know in advance which of the ESU control channels correspond to the four (4) electrodes 106 on the surgical probe component 100 and which of the ESU control channels correspond the four (4) temperature sensors 222 on the clamp component 200. In one exemplary configuration, control channels 1-4 may be used for the surgical probe component electrodes 106 and control channels 5-8 may be used for the four clamp component temperature sensors 222.
The ESU 422 is capable of performing both unipolar and bipolar tissue coagulation procedures in both the probe mode and the clamp mode. During unipolar procedures performed with the exemplary system 1000 illustrated in
It should also be noted that the tissue coagulation systems 1000-1000b may be provided with a suction device that can be secured to the distal portion of the surgical probe component 100 as well as a suction source that can be connected to the suction device. The suction device and suction source may be used to convert surgical probe component 100 into a surgical probe component that has suction capability. The suction prevents the distal portion of surgical probe from moving after the physician has placed it adjacent to the target tissue region. Suitable suction devices and suction sources are described in U.S. Patent Pub. No. 2004/0186467, which is entitled “Apparatus for Maintaining Contact Between Diagnostic and Therapeutic Elements and Tissue and Systems Including the Same” and U.S. application Ser. No. 10/784,316, which is entitled “Cooled Probes And Apparatus For Maintaining Contact Between Cooled Probes And Tissue,” both of which are incorporated herein by reference.
Referring to
As illustrated for example in
The exemplary tissue coagulation systems 1000-1000b illustrated in
First, the surgical probe component 100 (or 100b) may be secured to the one of the clamp members 312 and 314 of the clamp 300 with the probe support 200, the clamp component 220 (or 220a or 220b) may be secured to the other clamp member, and the dual mode lesion formation apparatus 10 (or 10a or 10b) may be connected to the ESU 422 by way or the clamp mode electrical connector 160. The clamp 300 may then be used to position the probe component distal portion 114 (and, therefore, the electrodes 106 and temperature sensors 150) on left atrial tissue adjacent to one side of the right pulmonary vein pair and to position the clamp component temperature sensors 222 on left atrial tissue adjacent to the opposite side of the right pulmonary vein pair. The clamp members 312 and 314 may then be brought into a completely closed orientation or, depending on the tissue structure, a slightly open orientation so long as the pulmonary veins are firmly held. The ESU 422 is used to supply coagulation energy to one or more of the electrodes 106, and energy is returned to the ESU by way of the indifferent electrode 434 (unipolar mode) or by way of the electrode 244 if the apparatus 10b is employed (bipolar mode). Energy will be continued to be supplied in a controlled manner based on the temperatures monitored by the temperature sensors 150 and 222 until a transmural epicardial lesion around the right pulmonary vein pair is formed (as indicated by the temperature measured at the temperature sensors 222). This process is then repeated on the left pulmonary vein pair and, if necessary, around the left atrial appendage. It should be noted, however, that individual lesions may be formed around each of the pulmonary veins instead of around the pulmonary vein pairs.
The surgical probe component 100 (or 100b) may then be separated from the clamp 300 and the probe support 200, clamp component 220 (or 220a or 220b) and the clamp may be placed on the sterile drape covering the patient, where it can remain until the coagulation procedure is completed.
The surgical probe component 100 (or 100b) may then be used, if necessary, to touch up the aforementioned lesions. If the dual mode lesion formation apparatus 10 (or 10a or 10b) is to be used in probe mode, the ESU 422 will be disconnected from the clamp mode electrical connector 160 and re-connected to the lesion formation apparatus by way of the probe mode electrical connector 158. Tissue coagulation energy from the ESU 422 will be supplied to one, some or all of the electrodes 106 and returned to the ESU by way of the indifferent electrode 434 (unipolar mode) or a non-transmitting electrode 106 (bipolar mode). In addition to touching up lesions, the surgical probe component 100 (or 100b) may be used to create a linear transmural epicardial lesion between the right and left pulmonary vein pairs and/or a linear transmural lesion that extends from the lesion between the right and left pulmonary vein pairs to the left atrial appendage.
The method steps described above are summarized in the flow chart illustrated in
The system 1000b may also be used to determine whether or not a therapeutic lesion (or “complete block”) has been formed. For example, the tissue stimulation electrodes 166 and 168 may then be used to supply a bipolar pacing pulse (e.g. about 20 mA) on the side opposite the left atrium of a lesion formed with the dual mode lesion formation apparatus 10b. The physician can determine whether or not a therapeutic lesion has been formed by observing the left atrium. If the pacing pulse is able to cross the lesion, the heart will beat faster (e.g. 120 beats/minute). This may be determined by observation or by use of an ECG machine that is monitoring the heart. Here, additional coagulation will be required to complete the lesion. The failure to stimulate the heart from the side of the lesion opposite the left atrium is, on the other hand, indicative of the formation of a therapeutic lesion. Nevertheless, because muscle bundles are not always connected near the pulmonary veins, it is preferable that the stimulation energy be applied to a number of tissue areas on the side of the lesion opposite the left atrium to reduce the possibility of false negatives. Alternatively, the tissue stimulation electrodes 166 and 168 may be used to monitor tissue within the region that was intended to be isolated. In the context of pulmonary vein isolation, for example, the tissue stimulation electrodes 166 and 168 may be placed in contact with viable tissue on the pulmonary vein side of the lesion.
Although the inventions disclosed herein have been described in terms of the preferred embodiments above, numerous modifications and/or additions to the above-described preferred embodiments would be readily apparent to one skilled in the art. By way of example, but not limitation, the electrical connectors 158 and 160 may be located at the end of one or more cables that extend(s) outwardly from the handle 104, instead of being located within the handle, so that the cable 424 may be eliminated. The inventions includes any combination of the elements from the various species and embodiments disclosed in the specification that are not already described as well as systems that comprise a power supply device (such as an ESU) and/or a fluid supply device and/or a source of simulation energy in combination with any of the apparatus claimed below. It is intended that the scope of the present inventions extend to all such modifications and/or additions and that the scope of the present inventions is limited solely by the claims set forth below.
Claims
1-23. (canceled)
24. A lesion formation method, comprising:
- positioning a clamp-based tissue coagulation device adjacent to a tissue structure such that at least one energy transmission element is located on a first side of the tissue structure and at least one temperature sensor is located on a second side of the tissue structure;
- supplying tissue coagulation energy to the first side of the tissue structure with the at least one energy transmission element; and
- discontinuing the supply of tissue coagulation energy to the first side of the tissue structure when a predetermined temperature is measured on the second side of the tissue structure by the at least one temperature sensor.
25. A lesion formation method as claimed in claim 24, wherein discontinuing the supply of tissue coagulation energy comprises discontinuing the supply of tissue coagulation energy to the first side of the tissue structure when a temperature between about 50.degree. C. and 60.degree. C. is measured on the second side of the tissue structure by the at least one temperature sensor.
26. A lesion formation method as claimed in claim 24, wherein discontinuing the supply of tissue coagulation energy comprises discontinuing the supply of tissue coagulation energy to the first side of the tissue structure when a predetermined temperature is measured on the second side of the tissue structure by the at least one temperature sensor for at least three seconds.
27. A lesion formation method as claimed in claim 24, further comprising:
- providing at least one of an audible indication and a visible indication in response to the predetermined temperature being measured on the second side of the tissue structure by the at least one temperature sensor.
28. A lesion formation method as claimed in claim 24, wherein positioning the clamp-based tissue coagulation device comprises positioning the clamp-based tissue coagulation device adjacent to at least one pulmonary vein such that at least one energy transmission element is located on a first side of the at least one pulmonary vein and at least one temperature sensor is located on a second side of the at least one pulmonary vein.
29. A lesion formation method as claimed in claim 24, further comprising:
- sensing tissue temperature at the at least one energy transmission element; and
- controlling the tissue coagulation energy supplied by the at least one energy transmission element based on the temperature sensed at the least one energy transmission element.
30. A method of forming a lesion in a tissue structure with a dual mode lesion formation apparatus including probe component, a clamp component, a clamp mode electrical connector and a probe mode electrical connector, the method comprising:
- connecting one of the probe mode electrical connector and the clamp mode electrical connector of the dual mode lesion formation apparatus to a source of tissue coagulation energy; and
- transmitting the tissue coagulation energy to the tissue with the probe component.
31. A lesion formation method as claimed in claim 30, wherein connecting comprises connecting the probe mode electrical connector to a source of tissue coagulation energy.
32. A lesion formation method as claimed in claim 31, wherein connecting comprises connecting the clamp mode electrical connector to a source of tissue coagulation energy.
33. A lesion formation method as claimed in claim 32, further comprising:
- positioning the probe component on one side of the tissue structure with one clamp member and positioning the clamp component on another side of the tissue structure with another clamp member.
34. A lesion formation method as claimed in claim 33, further comprising:
- measuring tissue temperature with the clamp component.
35. A lesion formation method as claimed in claim 33, wherein positioning the probe component comprises positioning the probe component on one side of at least one pulmonary vein with one clamp member and positioning the clamp component on another side of the at least one pulmonary vein with another clamp member.
36. A lesion formation method as claimed in claim 30, further comprising:
- disconnecting the one of the probe mode electrical connector and the clamp mode electrical connector from the source of tissue coagulation energy;
- connecting the other of the probe mode electrical connector and the clamp mode electrical connector to the source of tissue coagulation energy; and
- transmitting the tissue coagulation energy to the tissue with the probe component.
Type: Application
Filed: Jan 12, 2011
Publication Date: May 12, 2011
Applicant: BOSTON SCIENTIFIC SCIMED, INC. (Maple Grove, MN)
Inventors: William G. Landis (San Jose, CA), Greg Eberl (Sunnyvale, CA), David K. Swanson (Campbell, CA)
Application Number: 13/005,429
International Classification: A61B 18/14 (20060101);