WO2018160454A1

WO2018160454A1 - Controlling esophageal temperature during cardiac ablation

Info

Publication number: WO2018160454A1
Application number: PCT/US2018/019410
Authority: WO
Inventors: John N. CATANZARO
Original assignee: University Of Florida Research Foundation, Inc.
Priority date: 2017-02-28
Filing date: 2018-02-23
Publication date: 2018-09-07

Abstract

A flexible tube is inserted into the esophagus to cool or warm the esophagus, particularly during certain procedures which can tend to change the temperature in the area of the esophagus. The tube is inserted through the mouth and throat to a position, for example, proximate the heart, but within the esophagus. A sleeve having openings or ports through it is passed over the flexible tube, and can be slid upwards or downwards over the flexible tube when both the tube and sleeve are inside the body. The sleeve forms a seal with the tube, so that when the openings of the sleeve are aligned with openings in the tube, liquid can pass through both, but when the sleeve is slid to where the openings do not align, liquid flow from the tube is blocked. The liquid is heated or cooled, and can include a therapeutic substance.

Description

CONTROLLING ESOPHAGEAL TEMPERATURE

DURING CARDIAC ABLATION

FIELD OF THE DISCLOSURE

The disclosure relates to a system and method for controlling esophageal temperature during cardiac ablation, and in particular, to changing the temperature in an interior of the esophagus.

BACKGROUND OF THE DISCLOSURE

Ablation of tissues surrounding the pulmonary veins is carried out to disrupt an electrical signal transmitted from the veins into the left atrium, giving rise to atrial fibrillation. One technique for creating this ablation is the Convergent Procedure, which uses radio frequency energy to generate heat which is applied to heart tissue to produce ablation and interrupt the signal.

Radiofrequency ablation specifically left atrial endocardial ablation or pulmonary vein isolation in patients with symptomatic paroxysmal or persistent atrial fibrillation uses radiofrequency energy applied to the left atrium at the ostium of the pulmonary veins and sometimes on the posterior wall. An atrial Esophageal fistula is a known and debilitating (if not fatal) complication resulting in fistula formation between the atrium and esophagus with entry of air into the left atrium. This may lead to cerebrovascular attack and or myocardial infarction. In addition to standard pulmonary vein isolation, the Convergent Procedure is generally performed in patients with symptomatic persistent atrial fibrillation. An initial part of the procedure utilizes an RF probe or coil which is placed transdiaphragmatically on an exterior surface of the heart on the posterior wall of the epicardium, in an effort to ablate the epicardial posterior wall. The device utilizes RF energy emitted from a generator which is grounded to the patient. A coil apparatus is introduced telescopically onto the epicardium which then uses a vacuum suction while applying the RF energy. The impedance is measured while RF is applied in an effort to confirm that the application of energy is complete, and that sufficient energy has been transmitted to the epicardium in order to cause ablation.

To complete a desired ablation pattern near the blood vessels, ablation is additionally performed inside the heart using electrophysiology. A device is threaded through the femoral artery into the heart, and RF energy is again used to complete portions of the ablation pattern which could not be completed outside the heart. Cryothermal energy has been used inside the heart on the endocardium to ablate the ostium of pulmonary veins, including for example by use of the ARTIC FRONT device of Medtronic, Inc. The device occludes the ostium with a round balloon-like structure which is inserted into the ostium to make contact with body tissue, and which is then filled with a coolant to cause freezing of tissue at the ostium.

Laser ablation has also been used to isolate the pulmonary veins in symptomatic paroxysmal atrial fibrillation via an endoscopic balloon introduced transseptally into the left atrium. The probe is placed into the pulmonary vein and the balloon is deployed giving the operator visualization of the pulmonary vein before applying laser application. Laser application can increase left atrial temperature and predispose the esophagus to collateral damage via thermal injury

All of the above modalities have a latent effect of energy, that is, when stopping radiofrequency, or laser, the temperature measured in the esophagus continues to rise to a plateau before nadir. Cryothermal may have the same effect but in an opposite direction "freeze".

SUMMARY OF THE DISCLOSURE

In accordance with the disclosure, a device for cooling or warming an interior area of the esophagus during a therapeutic procedure comprises a flexible tube passable from outside of the body to the interior area of the esophagus and including a plurality of liquid passing ports formed through the tube; a flexible sleeve slideable in connection with the tube and including a plurality of liquid passing ports formed through the sleeve, the sleeve sized with respect to the tube to form a liquid tight seal with the tube such that when a port of the sleeve is aligned with a port of the tube, liquid may pass through the sleeve and the tube, and when no ports of the sleeve are aligned with a port of the tube, no liquid passes through the sleeve and the tube, the sleeve slideable along the tube to align a port of the sleeve with a selected port of the tube to pass fluid through the selected port of the tube to the interior area of the esophagus.

In variations thereof, the device further includes one or more temperatures sensors connected to the tube and configured to output temperature information pertaining to the interior area of the esophagus; the device further includes a plurality of temperature sensors positioned along a length of the tube and configured to output temperature information pertaining to a plurality of areas of the esophagus; the tube forms at least one bend whereby the tube is passable back outside of the body, the tube thereby forming two ends both outside of the body, the one or more tube ports positionable proximate the interior area of the esophagus; the sleeve is slideable within the tube; and/or the sleeve is slideable along an exterior of the tube. In further variations thereof, the device further includes a second tube connected to the flexible tube, the second tube configured with one or more openings, the second tube connectable to a source of negative pressure to aspirate fluid that has been released through aligned ports of the tube and sleeve; the device further includes an eluting extension which releases a therapeutic substance into the flexible tube, for release into the body through the flexible sleeve; and/or the device further includes an eluting extension which is positioned outside of the flexible tube and sleeve, and which is contacted by liquid that has passed through the sleeve, to thereafter elute a therapeutic substance.

In still further variations thereof, a distal end of the flexible tube that is passed first into the body is surrounded by an outer tube which captures liquid which has passed through the flexible sleeve; a distal end of the flexible tube that is passed first into the body being surrounded by a balloon which captures liquid which has passed through the flexible sleeve; the device further includes a second tube connected to the flexible tube, the second tube configured with one or more openings, the second tube connectable to a source of negative pressure to aspirate fluid that has been released through aligned ports of the tube and sleeve; and/or the flexible tube is formed into a coil.

In other embodiments thereof, a steerable element is inserted into an interior of the flexible tube, the steerable element configured to be bent when positioned inside the body and in the interior of the flexible tube, to thereby cause a change in an orientation of the flexible tube within the body; the liquid further includes solids thereby forming a slurry; the liquid is a slurry containing at least one of a calcium carbonate, an acid reducing substance, an agent which reduces the formation of acid in the digestive tract; and/or the liquid includes a substance which expands in the body to release a therapeutic substance.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present disclosure, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:

FIG. 1 depicts a diagrammatic cross-sectional view of the esophagus and left atrium, and a device of the disclosure which is releasing a liquid at a desired cooling or warming temperature, from a selected port, onto an interior surface of the esophagus;

FIG. 1 A depicts an alternative device of the disclosure, in which ports are formed by an external sliding sleeve;

FIG. 2 depicts a proximal end of a device of the disclosure, and deployment within the body; FIG. 3 depicts a multilumen configuration of the disclosure;

FIG. 4 depicts an alternative device of the disclosure, also releasing a liquid upon an interior surface of the esophagus, the liquid retrieved using an aspiration channel;

FIG. 5 depicts the device of claim 3, without the aspiration channel;

FIG. 6 depicts the device of claim 3, connected to a steerable device in accordance with the disclosure;

FIG. 7 depicts an alternative device of the disclosure in which a warming or cooling liquid is passed through the device within an interior of the esophagus, the liquid not being released into the esophagus;

FIG. 8 depicts an alternative device of the disclosure in which a warming or cooling liquid is passed through the device within an interior of the esophagus, the liquid being released into a flexible balloon, and including an aspiration channel disposed within the balloon;

FIG. 9 depicts an alternative device of the disclosure in which a warming or cooling liquid is circulated through separate coils positioned within an interior of the esophagus;

FIG. 10 depicts an alternative device of the disclosure in which a substance is discharged inside of a tube placed within the esophagus;

FIG. 11 depicts the tube of FIG. 10, further including a core extension which elutes or releases a therapeutic substance;

FIG. 12 depicts an alternative embodiment of the disclosure in which a therapeutic substance is introduced into a balloon which expands and can release the substance through pores;

FIG. 13 depicts the balloon of FIG. 12, further including a core extension which elutes or releases a therapeutic substance;

FIG. 14 depicts an embodiment of the disclosure including an open loop/closed loop system with an eluting core;

FIG. 15 depicts a device of the disclosure including an expandable sponge, the sponge in a contracted state;

FIG. 16 depicts the device of FIG. 15, the sponge in an expanded state, filled with an expandable material;

FIG. 17 depicts a device of the disclosure including a balloon filled with an expandable material, the balloon in a deflated or partially deflated state;

FIG. 18 depicts the device of FIG. 17, the balloon fully inflated; and

FIG. 19 depicts a wireless communication device, some or all of which can be used in carrying out the disclosure; DETAILED DESCRIPTION OF THE DISCLOSURE

As required, detailed embodiments are disclosed herein; however, it is to be understood that the disclosed embodiments are merely examples and that the systems and methods described below can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present subject matter in virtually any appropriately detailed structure and function. Further, the terms and phrases used herein are not intended to be limiting, but rather, to provide an understandable description of the concepts.

The terms "a" or "an", as used herein, are defined as one or more than one. The term plurality, as used herein, is defined as two or more than two. The term another, as used herein, is defined as at least a second or more. The terms "including" and "having," as used herein, are defined as comprising (i.e., open language). The term "coupled," as used herein, is defined as "connected," although not necessarily directly, and not necessarily mechanically.

In accordance with the disclosure, open or closed loop irrigation of cooling or warming liquid is applied to an interior surface of the esophagus that is proximate to the heart during a procedure which is applying heat or cold to the heart, and particularly in the region of the left atrium 302 (FIG. 1) which is most proximate the esophagus. Such procedures can include ablation of the heart using heat, such as during radio frequency or laser ablation, or ablation of the heart using cooling, such as during cryoablation. A device of the disclosure is used to apply a cooling liquid to an interior surface of the esophagus during heat ablation, and a cooling liquid during cold ablation. The applied liquid acts as a medium to counterbalance a resultant and undesired change in temperature of the esophagus, which can otherwise damage the esophagus during the therapeutic treatment of the heart. Such damage can include the formation of ulcers or an esophageal fistula, for example. The disclosure provides medical devices that improve the safety of left atrial ablation by reducing the incidence and severity of esophageal injury, by providing for targeted temperature control.

The apparatus can also help the electrophysiologist or cardiothoracic surgeon gain information on which types of lesion orientation from the catheter (sliding, parallel or perpendicular can afford a transmurality lesion while preserving the integrity of the esophagus.

The disclosure provides closed, semi-closed, and open loop irrigation devices and methods. As discussed further below, closed loop devices, such as are shown in FIGS. 6-8, do not release any liquids into the esophagus. Semi-closed devices, such as is shown in FIG. 1, do release liquid at predetermined temperatures to directly contact the esophagus with the liquid at a desired treatment site, but recover all remaining liquid that has not been released. Open loop devices, such as are shown in FIGS. 3-5, additionally release liquids at locations other than a desired treatment site, although the devices of FIGS. 3 and 5 attempt to aspirate such released liquids using suction.

With reference to FIG. 1, a device 100 of the disclosure includes a tube 110 which passes into the esophagus forming an inlet 112 and a supply channel 126, at least one bend 122, and an outlet 114 disposed at the end of a return channel. A sleeve 116 is disposed within tube 110 and includes a plurality of ports 118. Tube 110 is illustrated as a linear channel with a single loop or bend 122, for clarity; however, it should be understood that tube 110 can be formed in the shape of a coil, such as is illustrated in FIG. 8, or in another shape or pattern. For example, tube 110 can have the shape of a closed ended sleeve, e.g. a test-sleeve shape, with interior channels connected to inlet 112 and outlet 114. An upper portion indicated by brace "A" continues up and out of the esophagus, as illustrated in FIG. 2.

Interiorly disposed slideable sleeve 116 passes through a portion of an interior of tube 110, and includes a plurality of ports 118 mutually spaced apart along a length of sleeve 116, and which open a passage an interior of sleeve 116 to an exterior of sleeve 116. Sleeve 116 is sized to form a liquid tight seal against an interior of tube 110. Mating ports are provided along tube 110, whereby when a port 118 is aligned with a port 120, liquid within sleeve 116 can be released or sprayed from tube 110, where it may contact an adjacent area of esophagus 300 to either cool or warm such area. In FIG. 1, a second or middle port 120A of tube 110 is aligned with aligned port 118A of sleeve 116. The relative spacing of ports 118 is selected to align only one mating port set of port 118 and 120 at the same time. Other alignments of ports 118 and 120 can be configured where more than one mating port pair are opened simultaneously. While sleeve 116 is illustrated as positioned along supply channel 126, it can also or alternatively be positioned, together with ports 120, along return channel 124.

Port openings can have a diameter of, for example, 0.4 mm, although they may be much smaller or larger, for example 0.01 mm to 5 mm. For smaller diameters, or other configurations in which a potentially undesirable build-up of pressure can take place within the body, it can be advantageous to provide a pressure relief valve outside of the body.

As additionally shown in FIG. 1, a temperature sensor 130 is positioned at one or more location along tube 110. Sensor 130 can transmit temperature data corresponding to an adjacent area along the esophagus 300. A plurality of sensors can provide temperature information for a plurality of areas along esophagus 300, whereby signal processing equipment connected to sensors 130 can identify particular areas of the esophagus which are experiencing or anticipated to experience an undesired temperature change. Sensors 130 can transmit this data via wires 148 (FIG. 7), or by a wireless communication, such as WIFI, BLUETOOTH or other nearfield protocol, and any other wireless protocol. To avoid inadvertent heating of sensor 130 by radiofrequency associated with RF ablation, it can be advantageous to avoid using metal in sensor 130. This may be achieved using a non-metallic thermocouple, for example. Other non- metallic or metallic temperature sensor technologies may be used for sensor 130.

In an embodiment, an electronic processor 802 receives temperature information from sensors 130, and causes movement of sleeve 116 to aligns ports 118 and 120 at one or more locations most proximate to a sensor reporting an undesired esophageal temperature.

Alternatively, a medical practitioner can view analog or digital readouts of temperature sensors 130, and can compare reference information of port locations with the sensor 130 reporting an undesired temperature, and using indicia (not shown) placed upon tube 110 and sleeve 116, slide sleeve 116 relative to tube 110 to align desired ports for release of temperature stabilizing liquid proximate an area of undesired esophageal temperature.

FIG. 1 A illustrates that sleeve 116 can pass over an outside of tube 110, to thereby expose ports 118 and 120 as described above, and in other respects the device of FIG. 1 A functions as described herein. Devices lOOA-C and E can be similarly adapted.

FIG. 2 diagrammatically depicts device 100 deployed within the body, passing from outside the body into the esophagus 300. While slideable sleeve 116 and return channel 124 appear as separate tubes, as shown in FIG. 3, it should be understood that they may be formed as lumens within a common or multilumen catheter tube 110. Other lumens 128 may be provided within catheter tube 110, through which other materials may be passed, such as electrical wires, additional sensors, surgical instruments, gases, or as further described herein, steerable devices. FIG. 2 illustrates one method of passing a fluid into slideable sleeve 116, while enabling sleeve 116 to be moved within tube 110, and to receive unreleased or recaptured fluid from outlet 114. It would be understood within the art that there are other methods for separately admitting or receiving fluids or materials through the various lumen of a multilumen catheter.

With reference to FIG. 4, in device 100A, bend 122 is not present, and the distal ends 132, 134 of tube 110 and slideable sleeve 116, respectively, are sealed. Return channel 124 is provided with one or more aspiration ports 138, and outlet 114 is connected to a source of vacuum, whereby fluids released adjacent to the ports 138 are aspirated out of esophagus 300 after contacting esophagus 300. A distal end 140 can be open and serve as an aspiration port, or it may be closed. As such, fluid may be admitted into tube 110 and slideable sleeve 116 at a lower pressure than for device 100 for a similar spray velocity at active port 118A/120A. While recovery of warming/cooling fluid may not be as efficient as for device 100, it may be sufficient depending on the total amount of fluid to be released, and the effect of the released fluid upon the esophagus or other components of the digestive system. If it is not necessary to recover fluid, device 100B of FIG. 5 can be used, which is similar to device 100A, but omits return channel 124 and associated ports 128.

In accordance with the disclosure, suction can be applied to housing 110, exposed through ports 1136, or ports formed by distal ends 140, 140A, or other port, which can be used to attach or draw device 100 towards selected areas of body tissue. A separate channel can be provided for this purpose.

In FIG. 4, active ports 118A/120A are aligned to illustrate release from a second port, and in FIG. 5, active ports 118A/120A are aligned to illustrate release from a third, or lowest port. The selection of port for the illustration is arbitrary, however, and it should be understood that any port may be activated for either device 100A/100B, as well as for other devices of the disclosure, as described herein.

In FIG. 6, device lOOC includes the components of device 100 A of FIG. 4, and further includes a steerable device 150, such as a steerable catheter or other device which enables distal manipulation in the manner of a steerable catheter (e.g. with or without an associated lumen), connected along all or part of its length to sleeve 116 and channel 124, whereby as steerable device is manipulated to bend as is known in the art, remaining components of device lOOC are similarly manipulated to be moved within esophagus 300. For example, device lOOC can be moved by the steerable device to be closer or farther from an area indicated by a sensor 130 that has an undesired temperature. It is noted, however, that there is some clinical evidence that it may be undesirable to forcibly press a wall of esophagus during ablation, particularly if such action moves tissue of the esophagus closer to left atrium 302, other otherwise closer to a region of ablation. Steerable device can be configured to extend out of the mouth of the patient in order to be manipulated, as understood within the art.

As shown in FIG. 7, device 100D includes the components of device 100 and steerable device 150 as described with respect to FIG. 6, and further includes an external flexible housing 142 surrounding all components, extending along all or a portion of a length of the components. While the device of FIG. 1 is illustrated within housing 142, it should be understood that any of the devices of the disclosure, for example including any of devices 100A-F, can be entirely or partially enclosed by housing 142, and/or can include steerable device 150, as described herein. Housing 142 facilitates inserting and removing devices of the disclosure by forming a smooth exterior surface, and can be fabricated with a material that is non-reactive and non-allergenic, to isolate housed components from contact with body tissue, thereby facilitating the selection of materials for the housed components.

In FIG. 8, components at a distal end of device 100E of the disclosure are enclosed within a flexible housing 144 which can be semi-rigid or inflatable. Housing 144 is sized, configured, or is inflatable to conform to an interior perimeter of esophagus 300. Housing 144 can be fabricated using a flexible polymer or other biocompatible material of predetermined shape, that is sufficiently flexible to be reduced in size during deployment to be passable to the treatment site within the esophagus. Alternatively, housing 144 can include a flexible outer skin, and further include a resilient internal scaffold, for example of shape memory alloy, which is reversibly collapsible. As a further alternative, housing 144 can be formed as an inflatable balloon, where pressurized air is passed through tube 110, or another lumen of a multilumen catheter, as described herein. In each variation, housing 144 can expand or is expandable to contact the inner surfaces of the esophagus when positioned at a selected location along the esophagus.

Once positioned, device 100E can be used as otherwise described for the various embodiments of device 100 described herein which release, emit, or spray a fluid from aligned ports 118 A/120 A. However, housing 144 is fabricated with an outer material which will not pass a warming/cooling fluid outside housing 144. Accordingly, as an outer material of housing 144 is cooled or warmed, it will cool or warm esophageal tissue which it contacts, thereby providing the therapeutic benefit described herein of controlling the temperature of an area of the esophagus. FIG. 8 depicts an open loop fluid retrieval system; however, housing 144 can be used with the partially open or closed systems described herein. While housing 144 is illustrated as only being present at a distal end of device 100E, housing 144 can continue proximally along any length of device 100E, whether or not ports 120 extend along such lengths.

In device 100E, distal end 140A of return channel 124 is positioned proximate a lower end of housing 144, to be positioned within accumulated warming/cooling fluid which may then be aspirated. As such, ports 136 are not necessary, although they may be provided to increase capacity. Wires 148 communicating from sensors 130 to outside of the body are illustrated passing through channel 124, although they may pass along another route, as detailed with respect to FIG. 3.

FIG. 9 depicts device 100F of the disclosure, in which one or more coils 152, two of which are illustrated as 152 and 152', each providing a circuit for the flow of cooling/warming liquid. The coils include tubes 110 which can include slideable sleeves 116, but, in this embodiment, do not. More particularly, coils 152 can be disposed with respect to each other, so that each coil is adjacent to a different area of the interior of esophagus 130. In the embodiment shown, coils 152 are positioned vertically or successively disposed with respect to each other, although coils 152 can additionally or alternatively be placed side by side with respect to each other. In this manner, fluid can be directed preferentially or solely through a coil which is proximate to an area of esophagus which is expected to be experiencing an undesired temperature change, or which is actually experiencing such temperature change as indicated by sensors 130, as described elsewhere herein. Each coil 152 is formed as a tube 110 which includes an includes a supply channel 126 and a return channel 124. As shown, the channels can be nested within the coil to produce a device of smaller diameter. In an embodiment, these channels can be connected to valves (not shown) positioned inside or outside of the body, which valves may be controlled in a known manner to select a particular coil or coils for controlled amounts of fluid flow.

Coils 152 can be placed within an outer sleeve or housing, not shown, to provide further structural integrity and to ease insertion and removal from the body. In an embodiment, a sleeve can be slid over coils 152 or portions of coils 152, to either cover and insulate them, or to selectively expose coils to desired portions of the esophagus. As with other embodiments herein, a steerable device 150 can be associated with coils 152 so that they can be therapeutically located laterally within the esophagus, either closer or farther from an area of undesired esophageal temperature.

Turning now to FIG. 10, a device 100G of the disclosure includes a flexible closed ended tube 160 which forms a housing to contain a tube 110 having one or more ports 120. A cooled or heated liquid or gel is passed into tube 110 via supply channel 126, to be discharged at ports 120 against an inner surface of tube 110. As such, tube 110 is cooled or heated proximate the area or areas of discharge, to thereby change a temperature of the esophagus 300 adjacent to the areas of discharge.

Fluid that has been discharged collects at the bottom of tube 160, where it may remain during a therapeutic procedure, or where it may be aspirated, for example using a return tube 162, having a distal opening 140B near a distal end of tube 160. The discharged fluid is drawn through return channel 124, where it may again be cooled or heated and reused, or it may be discarded.

Tube 162 is depicted as a separate tube that is viewed partially behind tube 110 in FIG. 10, although tube 162 can be realized in other known forms, such as a lumen associated with tube 160, for example. Tube 162 may also be inserted within tube 160 when the level of discharged fluid is known to be of a predetermined volume, and can be removed after the fluid is aspirated.

Tube 160 is shown with a coating 164 which can include any or all of a lubricious coating as known in the art to facilitate insertion into the esophagus; a therapeutic substance; and a substance which can be heated or cooled to therapeutically treat the esophagus.

Examples of substance which can heated or cooled include gels such as are used for ultrasound (e.g. propylene glycol and glycerin with water), an agar gel, or other viscous biocompatible liquid with heat or cold retaining properties at least as good as or advantageously better than water. The viscosity and adhesive qualities of the substance causes the substance to initially cling to tube 160, and in turn, to transfer to the esophagus upon contact, thereby transferring the heat or cold and any included ingredients, for example by elution, to the esophagus. Alternatively, the viscous substance, which may be in the form of a slurry or may elute from a substrate, can be selected to include materials which expand with heat of the body, such as but not limited to an agar, thereby releasing a therapeutic substance.

A therapeutic substance can include a material to reduce acid, and the effects of acid, in the area of treatment, for example a slurry of coating solution containing calcium carbonate or other acid neutralizing substance, or an agent which reduces the formation of acid in the digestive tract, including for example omeprazole, such as omeprazole magnesium. The eluting substance, or the coating upon tube 160, can be any other therapeutically beneficial substance or combination of substances, including for example agents which promote healing, antimicrobial agents, or drugs to treat a disease condition of the patient, including for example a drug to treat a condition of the esophagus or heart. Coating 164 can additionally be applied to the outer surface of other embodiments 100-lOOG, described herein, which may contact the esophagus.

FIG. 11 depicts device 100G, as well, although tube 162 has been removed for clarity. In

FIG. 11, a drug eluting core extension 168 extends within supply channel 126 of tube 110, whereupon a therapeutic substance is released as fluid flows through channel 126. In the embodiment shown, extension 168 has the form of an elongate rod, although other shapes can be used, such as a coil or lozenge. Additionally, extension 168 can be positioned outside of tube 110, and within tube 160, whereupon it will release the therapeutic substance when discharge through ports 120 occurs. The therapeutic substance can be combined with a binder, and coated upon extension 168, to release the substance upon contact with a liquid, such as water, as is understood within the art. Alternatively, the therapeutic substance can be incorporated into material which forms extension 168, to elute from extension 168, or to be released as extension 168 is dissolved by the heating or cooling liquid to be discharged. The therapeutic substance can be, for example, any of the substances listed herein with respect to coating 164. Extension 168 can be formed with a colloid, gel, sol, or emulsion, which dissolves to release, or otherwise releases the therapeutic substance in the body over time. Alternatively, extension 168 can be formed as a thermopolymer or other natural or synthesized substrate which elutes a substance when hydrated by an introduced fluid or by body fluid, or when warmed by the body.

With reference to FIGS. 12 and 13, a device 100H of the disclosure includes an expandable portion or balloon 144H which is in fluid communication with a tube 110 and supply channel 126. Balloon 144H includes a plurality of pores 120H through which a substance 166 introduced into supply channel 126 can flow to pass into contact with an inner surface of esophagus 300. Pores 120H are sized and provided in a sufficient number upon the surface of balloon 144H to cause substance 166 to pass at a predetermined desired rate. Accordingly, pore 120H size and quantity are determined in part based upon the viscosity of substance 166, as well as the pressure of substance 166 within balloon 144H. Substance 166 can be the same substance as described with respect to coating 164, including for example any or all of a lubricious coating, a therapeutic substance, and a substance which can be heated or cooled, as further described above.

Tube 110 can be connected to balloon 144H to extend within balloon 144H as shown in FIG. 12, or tube 110 may terminate at a peripheral surface of balloon 144H, as shown in

FIG. 13. In the example of FIG. 12, tube 110 can be used to push balloon 144H along the length of the esophagus, and to maintain balloon 144H in a desired deployment orientation extending at least along tube 110.

Balloon 144H can be inserted into the esophagus in a deflated, partially inflated, or fully inflated state. If not fully inflated, a gas or fluid can be used to inflate balloon 144H to a desired pressure once balloon 144H is in a desired position within the esophagus. The desired or optimal pressure can be chosen to achieve an estimated or actual: desired final size of balloon 144H; desired pressure of an introduced substance 166; desired internal pressure within balloon 144H; and/or stiffness of the balloon 144H material. While a combination of gas and fluid, different gases, or different fluids can be used to inflate balloon 144H, inflation can be carried out solely by introducing substance 166 at a faster rate than substance 166 can pass through pores 120H.

Following inflation, to maintain a predetermined extent of inflation, substance 166 can be introduced at about the same rate that substance 166 is collectively passing out of the balloon through pores 120H. To remove balloon 144H from the body, deflation may be carried out in advance if desired, by reducing the pressure at which the inflation medium is introduced.

Inflation medium can additionally be aspirated out of balloon 144H during deflation, or to discontinue passage of substance 166 through pores 120H into the body. Alternatively, to discontinue passage of substance 166, a material can be introduced into balloon 144H which causes substance 166 to become too viscous to pass through pores 120H, or which will collect at pores 120H to cause blockage of pores 120H. Where a gas is used to generate sufficient pressure within balloon 144H to cause substance 166 to pass through pores 120H, the gas pressure can be reduced below that required to cause such passage.

In an embodiment, the gas introduced into balloon 144H is substance 166. As such, the gas can be heated or cooled, and can include one or more therapeutic gases, for example gases which reduce pain, treat tissue damage, or change pH within the body. In this embodiment, gas emitted through pores 120H substitutes for a desired lubricious property of a substance 166 which is a liquid. In FIG. 13, device 100H is shown without a rendering of the esophagus, and which contains a core extension 168 A, which elutes or releases a substance as described with respect to extension 168 of FIG. 11. Either core extension 168 or 168A can be linear or spiral shaped, as shown in FIGS. 10 and 13, or each may have any other simple or complex shape. Forming extension 168 A as a spiral facilitates inserting a longer extension, relative to a single linear shape, within balloon 144H.

In a variation of FIGS. 12-13, balloon 144H does not include pores 120H, and substance 164/166 is coated upon an exterior of balloon 144H prior to or subsequent to insertion into the esophagus. Thereafter, when balloon 144H is expanded inside the esophagus, the coating is brought into contact with the esophagus, or is positioned closer to an inner esophageal wall. The coating in this embodiment can be heated or cooled prior to insertion into the esophagus, or a substance 164/166 can be introduced into the esophagus after insertion, either before or after inflation, to be deposited upon an exterior surface of balloon 144H, where it can be cooled or heated previous to or after being so deposited. In such embodiments where pores 120H are not present, a heated or cooled substance can be introduced into an interior of balloon 144H, whereupon an external surface of balloon 144H will become heated or cooled. As such, with or without a coating 164 upon an external surface of balloon 144H, an interior surface of the esophagus can be treated by cooling or heating when balloon 144H is proximate or in contact with such surface.

With reference to FIG. 14, device 100J is constructed and used as described with respect to FIG. 1, with certain exceptions. In particular, a core or eluting extension 168 (shown with hatching) is inserted within sleeve 116. When device 100J is inserted into the body, eluting extension 168 is warmed to thereby release a therapeutic substance which protects or prepares the esophagus for the introduction of heat or cold applied during treatment of nearby tissues of the heart, as described herein. The therapeutic substance eluted or released when extension 168 is dissolved can be as described with respect to extension 168 of FIGS. 11 or 13, or other therapeutic substance disclosed herein.

In FIG. 14, ports 118 are all aligned simultaneously, so that the eluting substance can migrate through ports 118 of sleeve 116, and ports 120 of tube 110, and out of device 100 J, to be deposited upon an inner surface of the esophagus. While mutually aligned ports 118/120 are shown in FIG. 14, they may be staggered as shown in FIG. 1, for selective opening. Likewise, the ports in FIG. 1 may be aligned as shown in FIG. 14, as elements of the various embodiments herein may be combined or exchanged, as would be understood by one skilled in the art.

Once eluting extension 168 has eluted its therapeutic contents, or has dissolved releasing the therapeutic contents, or has expanded by heat of the body to drive the therapeutic substance through ports 118/120, ports 118 can be displaced by sliding tube 116 relative to tube 110, to close the passage through ports 118 and 120. A determination of when a particular therapeutic substance has been sufficiently released can be made, for example, in consideration of an amount of time during which extension 168 is at body temperature, a time elapsed since ports 118/120 were mutually opened, physiological parameters of the patient, or the dissolution of eluting extension 168, either by physically probing sleeve 116, or by indirect measurement, for example by testing an ability to flow a gas or fluid past eluting extension 168. Once ports 118/120 are mutually closed, cooling or heating can be carried out as described herein in a closed loop system as shown in FIG. 14, or by any other closed loop system described herein, for example using an outer tube 144 or 160, as shown in FIGS. 8 or 10, and can include a cooling/heating coil as described with respect to FIG. 9.

A process thereby can include any or all of the following steps: (a) introducing device 100 J and eluting extension 168 into the esophagus, (b) aligning ports 118/120, (c) waiting for or otherwise causing release of the therapeutic substance from eluting extension 168, for example by introducing a hydration fluid, or gas pressure, (d) mutually closing ports 118/120 when sufficient therapeutic substance has been released, and (e) introducing a cold or warm liquid or gas into inlet 112 to be received through outlet 114, to be thereby reheated or cooled and reintroduced into the closed system, or to be continuously reintroduced and discarded, and (f) to remove the system once the potential harm to the esophagus is no longer present.

The foregoing process can be carried out by medical personnel, for example by an anesthesiologist, and may be carried out with the assistance of computing technology as described herein. The computing technology can carry out any or all of gathering sensor input, such as that of temperature or pressure sensors, aligning or closing an opening between ports 118/120 or other port system, determining when a release of therapeutic substance is complete or sufficient, and activating pumps or flow associated with closed loop cooling or heating, for example.

Referring now to FIGS. 15-18, devices 100K-L include an expandable sponge 170 or balloon 144L which contains an expandable biocompatible material 172 which readily transmits heat or cold. Examples of such material include a viscous colloid or gel; a colloid or gel including glycerin; an expandable lattice polymer including for example a low carboxylate acid copolymer; a shape memory expandable polymer, including for example poly(propylene carbonate) (PPC)/polycaprolactone (PCL); expandable polymeric microspheres; or any thermally transferring material which can be expanded once placed at a therapeutic location within the esophagus 300. In FIGS. 15-16, a sponge 170 or sponge-like material surrounds any of the systems 100 depicted in FIGS. 1-7, 9, or 14. In FIGS. 15-16, a simple closed-loop system is depicted as shown in FIG. 7, for clarity, although it should be understood that an open-loop system as shown in the remaining figures can be used. In FIG. 15, sponge 170 is at least partially dried so that it has a smaller than maximum dimension, enabling device 100K to be more easily inserted into the esophagus and positioned at a site of therapy, for example near to the heart. It may be desired to retain some moisture within sponge 170, for example, to ensure that the surface thereof is soft and resilient, to protect body tissue.

As sponge 170 expands, material 172 can elute throughout sponge 170 and escape sponge 170 to contact the inner surface of esophagus 300, improving thermal transfer. Additionally, material 172 can comprise or include a therapeutic substance, for example a healing or antimicrobial agent, which can contact esophagus 300.

As device 100K is inserted, and while it is positioned, sponge 170 can begin to absorb body fluids, and expand to contact inner surfaces of esophagus 300. Cooled or heated fluid can then be circulated through tubes 110 as described elsewhere herein, to transfer or remove heat to or from the sponge. The expandable biocompatible material 172 within sponge 170 then transfers the heat or cold to the inner surface of the esophagus, providing the intended therapeutic benefit. Where an open or openable loop system is employed, liquid introduced into the system can be caused to at least partially escape into sponge 170, thereby accelerating expansion of sponge 170, and can, if desired, introduce additional material 172 into sponge 170. Sensor 130 can be provided, to function as described elsewhere herein and provide data regarding the efficacy of the heating or cooling process.

In an alternative embodiment, material 172A is substituted for material 172, and is a thermally expanding material, whereby when warm fluid is passed through tubes 110, material 172 A expands thereby causing sponge 172 to expand and contact inner surfaces of esophagus 300. Examples of material 172A include thermally activated shape memory polymers (SMPs), and thermally expanding colloids or gels.

Collapse of sponge 170 for withdrawal of system 100K can be achieved by withdrawing fluid 172 when a partially or fully open system is used; allowing sufficient time to lapse for sponge 170 to dry sufficiently, aspirating material from sponge 170, or gently applying pressure to sponge 170, for example during withdrawal, whereby fluid is forced from sponge 170. Where a thermally expanding material 172A is used, cooled fluids can be circulated through tubes 110 to cause contraction of material 172A, or material 172A can otherwise be allowed to cool and contract to facilitate removal of device 100K. In FIGS. 17-18, a balloon 144L is substituted for sponge 170 in device 100L. As described with respect to device 100K, tubes 110 can be formed as open or closed-loop systems, although a closed-loop system is shown in FIGS. 17-18 for clarity. Additionally, as described with respect to device 100K, material 172 as described above is introduced into balloon 144L either before or after insertion of device 100L. Similar to device 100K, balloon 144L is not fully inflated with material 172, or material 172 is not fully expanded, as device 100L is inserted into and positioned within the esophagus. Once positioned, balloon 144L can be further inflated by introducing a fluid or additionally material 172 using a partial or fully open system 100 of the disclosure, such as are shown in. FIG. 1 and FIG. 4, respectively, for example. Once balloon 144L is fully inflated, heating or cooling energy is transferred from the tubes 110, through material 172 and the surface of balloon 144L, to the inner surface of the esophagus.

Where the material is thermally expanding material 172A, heat energy introduced into tubes 110 causes expansion of material 172 A within balloon 144L, and thereby expansion of balloon 144L into contact with the inner surface of esophagus 300, thereby to transfer heat energy to the esophagus.

Deflation of balloon 144L for withdrawal of system 100L can be achieved by withdrawing fluid 172 when a partially or fully open system is used. Alternatively, balloon 144L can be pierced or otherwise torn or opened, for example with a rip cord extending outside of the body, to release material 172. Where a thermally expanding material 172A is used, cooled fluids can be circulated through tubes 110 to cause contraction of material 172 A, or material 172 A can otherwise be allowed to cool and contract to facilitate removal of device 100L.

Alternatively, balloon 144L can include small or microscopic pores which gradually release material 172/172 A, enabling gradual shrinking of balloon 144L. As described above, material 172/172 can comprise or include a therapeutic substance which is beneficial when contacting the esophagus.

In the various embodiments herein, element 168/168 A can be formed together with or as part of steerable element 150. For example, a steerable catheter or alternatively a stylet which is otherwise manipulable, can be coated with or formed with the colloid, dissolving, or eluting material which releases the therapeutic substance as described herein.

Features of the various embodiments herein may be combined or substituted. Non-limiting illustrative examples include: the use of the sliding port closing system of FIG. 1 or 1 A with other supply tubes, such as within tube 110 of FIGS. 10-13, to control the location and extent of discharge of substance 164; the use of core extension 168 within any embodiment; the use of coil 152 within tube 160 or balloon 166; the use of steerable device 150 with any embodiment; the use of external ports to deposit substance 164 upon balloon 144H; sensors with any embodiment; and/or the use of substance 164/166 to coat or be released by any embodiment.

Devices 100 of the disclosure can be used in the various manners described herein, and can additionally be advantageously used in outflow tract tachycardia or right ventricle ablations in the epicardium, particularly where the endocardium is thin. Additionally, devices 100 can be used to buffer the convective heat introduced from an ablation catheter, enabling in certain cases transmittal of full thickness lesions with a lower chance of perforation or collateral damage to adjacent epicardial arteries than in cases where devices 100 are not used.

Devices 100 of the disclosure can have any size which can be effectively inserted into the esophagus of a given patient, which varies widely according to human anatomy. An example non-limiting range of diameter includes 4 mm to 20 mm, and lengths of 250 to 500 cm. Smaller, wider, longer, or shorter sizes can be used depending upon the patient size, whether or not it is desired for the cooling/warming area of the device to contact the esophageal wall, and a length extending outside of the body that is convenient. Appropriate biocompatible materials can be used, as understood within the art, although the avoidance of metal is advantageous to avoid undesired retransmission of RF energy within the esophagus. Flexible components such as tube/sleeve 116 and housing/tube 110 are advantageously made with a biocompatible polymer with sufficient flexibility, durability, and lubricity, as would be understood within the art.

Examples can include Poly(ethylene) (PE) (HDPE, UHMWPE); Poly(propylene) (PP);

Poly(tetrafluroethylene) (PTFE) (Teflon), extended-PTFE; Ethylene-co-vinylacetate (EVA); Poly(dimethylsiloxane) (PDMS); Poly(ether-urethanes) (PU); Polyethylene terphthalate) (PET); and Poly(sulphone) (PS), although other materials, including polymeric, synthetic, and natural, can be used.

Example Computing Components

FIG. 19 is a block diagram of an electronic device and associated components 800, which can be used in carrying out the disclosure. In this example, an electronic device 852 is a wireless two-way communication device with voice and data communication capabilities. Such electronic devices communicate with a wireless voice or data network 850 using a suitable wireless communications protocol. Wireless voice communications are performed using either an analog or digital wireless communication channel. Data communications allow the electronic device 852 to communicate with other computer systems via the Internet. Examples of electronic devices that are able to incorporate the above described systems and methods include, for example, a data messaging device, a two-way pager, a cellular telephone with data messaging capabilities, a wireless Internet appliance or a data communication device that may or may not include telephony capabilities. Electronic device 800 can be used, for example, to gather electronic data from sensors 130 by wired or wireless means, to display such data or otherwise communicate such data to medical practitioners, and to control flow of cool or warm fluid through device 100.

The illustrated electronic device 852 is an example electronic device that includes two-way wireless communications functions. Such electronic devices incorporate communication subsystem elements such as a wireless transmitter 810, a wireless receiver 812, and associated components such as one or more antenna elements 814 and 816. A digital signal processor (DSP) 808 performs processing to extract data from received wireless signals and to generate signals to be transmitted. The particular design of the communication subsystem is dependent upon the communication network and associated wireless communications protocols with which the device is intended to operate.

The electronic device 852 includes a microprocessor 802 that controls the overall operation of the electronic device 852. The microprocessor 802 interacts with the above described communications subsystem elements and also interacts with other device subsystems such as flash memory 806, random access memory (RAM) 804, auxiliary input/output (I/O) device 838, data port 828, display 834, keyboard 836, speaker 832, microphone 830, a short-range communications subsystem 820, a power subsystem 822, and any other device subsystems.

A battery 824 is connected to a power subsystem 822 to provide power to the circuits of the electronic device 852. The power subsystem 822 includes power distribution circuitry for providing power to the electronic device 852 and also contains battery charging circuitry to manage recharging the battery 824. The power subsystem 822 includes a battery monitoring circuit that is operable to provide a status of one or more battery status indicators, such as remaining capacity, temperature, voltage, electrical current consumption, and the like, to various components of the electronic device 852.

The data port 828 of one example is a receptacle connector 104 or a connector that to which an electrical and optical data communications circuit connector (not shown) engages and mates, as described above. The data port 828 is able to support data communications between the electronic device 852 and other devices through various modes of data communications, such as high speed data transfers over an optical communications circuits or over electrical data communications circuits such as a USB connection incorporated into the data port 828 of some examples. Data port 828 is able to support communications with, for example, an external computer or other device.

Data communication through data port 828 enables a user to set preferences through the external device or through a software application and extends the capabilities of the device by enabling information or software exchange through direct connections between the electronic device 852 and external data sources rather then via a wireless data communication network. In addition to data communication, the data port 828 provides power to the power subsystem 822 to charge the battery 824 or to supply power to the electronic circuits, such as microprocessor 802, of the electronic device 852.

Operating system software used by the microprocessor 802 is stored in flash memory 806. Further examples are able to use a battery backed-up RAM or other non-volatile storage data elements to store operating systems, other executable programs, or both. The operating system software, device application software, or parts thereof, are able to be temporarily loaded into volatile data storage such as RAM 804. Data received via wireless communication signals or through wired communications are also able to be stored to RAM 804.

The microprocessor 802, in addition to its operating system functions, is able to execute software applications on the electronic device 852. A predetermined set of applications that control basic device operations, including at least data and voice communication applications, is able to be installed on the electronic device 852 during manufacture. Examples of applications that are able to be loaded onto the device may be a personal information manager (PIM) application having the ability to organize and manage data items relating to the device user, such as, but not limited to, e-mail, calendar events, voice mails, appointments, and task items.

Further applications may also be loaded onto the electronic device 852 through, for example, the wireless network 850, an auxiliary I/O device 838, Data port 828, short-range communications subsystem 820, or any combination of these interfaces. Such applications are then able to be installed by a user in the RAM 804 or a non-volatile store for execution by the microprocessor 802.

In a data communication mode, a received signal such as a text message or web page download is processed by the communication subsystem, including wireless receiver 812 and wireless transmitter 810, and communicated data is provided the microprocessor 802, which is able to further process the received data for output to the display 834, or alternatively, to an auxiliary I/O device 838 or the Data port 828. A user of the electronic device 852 may also compose data items, such as e-mail messages, using the keyboard 836, which is able to include a complete alphanumeric keyboard or a telephone-type keypad, in conjunction with the display 834 and possibly an auxiliary I/O device 838. Such composed items are then able to be transmitted over a communication network through the communication subsystem.

For voice communications, overall operation of the electronic device 852 is substantially similar, except that received signals are generally provided to a speaker 832 and signals for transmission are generally produced by a microphone 830. Alternative voice or audio I/O subsystems, such as a voice message recording subsystem, may also be implemented on the electronic device 852. Although voice or audio signal output is generally accomplished primarily through the speaker 832, the display 834 may also be used to provide an indication of the identity of a calling party, the duration of a voice call, or other voice call related information, for example.

Depending on conditions or statuses of the electronic device 852, one or more particular functions associated with a subsystem circuit may be disabled, or an entire subsystem circuit may be disabled. For example, if the battery temperature is low, then voice functions may be disabled, but data communications, such as e-mail, may still be enabled over the communication subsystem.

A short-range communications subsystem 820 provides for data communication between the electronic device 852 and different systems or devices, which need not necessarily be similar devices. For example, the short-range communications subsystem 820 includes an infrared device and associated circuits and components or a Radio Frequency based communication module such as one supporting Bluetooth® communications, to provide for communication with similarly-enabled systems and devices, including the data file transfer communications described above.

A media reader 860 is able to be connected to an auxiliary I/O device 838 to allow, for example, loading computer readable program code of a computer program product into the electronic device 852 for storage into flash memory 806. One example of a media reader 860 is an optical drive such as a CD/DVD drive, which may be used to store data to and read data from a computer readable medium or storage product such as computer readable storage media 862. Examples of suitable computer readable storage media include optical storage media such as a CD or DVD, magnetic media, or any other suitable data storage device. Media reader 860 is alternatively able to be connected to the electronic device through the Data port 828 or computer readable program code is alternatively able to be provided to the electronic device 852 through the wireless network 850.

All references cited herein are expressly incorporated by reference in their entirety. It will be appreciated by persons skilled in the art that the present disclosure is not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. There are many different features to the present disclosure and it is contemplated that these features may be used together or separately. Thus, the disclosure should not be limited to any particular combination of features or to a particular application of the disclosure. Further, it should be understood that variations and modifications within the spirit and scope of the disclosure might occur to those skilled in the art to which the disclosure pertains. Accordingly, all expedient modifications readily attainable by one versed in the art from the disclosure set forth herein that are within the scope and spirit of the present disclosure are to be included as further embodiments of the present disclosure.

Reference Numbers:

lOO/A-H -L device 168/168A eluting extension 104 receptacle connector 170 sponge

110 tubes 172 / 172 A expandable material 112 inlet 300 esophagus

114 outlet 302 left atrium

116 slideable sleeve 800 electronic device

118/A port 802 electronic processor 120/Aport 804 RAM

120H pore 806 flash memory

122 bend 808 DSP

124 return channel 810 wireless transmitter 126 supply channel 812 wireless receiver

128 lumen 814 / 816 antenna el ements 130 sensor(s) 820 comm subsystem

132 /134 distal ends 822 power subsystem

136 port 824 battery

138 port 828 data port

140/A/B distal end / port 830 microphone

142 housing 832 speaker

144 housing 834 display

144H,L balloon 836 keyboard

148 wires 838 aux I / O device

150 steerable device 850 wireless data network

152 coil 852 electronic device

162 return tube 860 media reader

164 coating/therapeutic substance 862 media

166 coating/therapeutic substance

Claims

What is claimed is:

1. A device for cooling or warming an interior area of the esophagus during a therapeutic procedure, comprising:

a flexible tube passable from outside of the body to the interior area of the esophagus and including a plurality of liquid passing ports formed through the tube;

a flexible sleeve

slideable in connection with the tube and

including a plurality of liquid passing ports formed through the sleeve, the sleeve sized with respect to the tube to form a liquid tight seal with the tube such that

when a port of the sleeve is aligned with a port of the tube, liquid may pass through the sleeve and the tube, and

when no ports of the sleeve are aligned with a port of the tube, no liquid passes through the sleeve and the tube,

the sleeve slideable along the tube to align a port of the sleeve with a selected port of the tube to pass fluid through the selected port of the tube to the interior area of the esophagus.

2. The device of claim 1, further including one or more temperatures sensors connected to the tube and configured to output temperature information pertaining to the interior area of the esophagus.

3. The device of claim 1, further including a plurality of temperature sensors positioned along a length of the tube and configured to output temperature information pertaining to a plurality of areas of the esophagus.

4. The device of claim 1, the tube forming at least one bend whereby the tube is passable back outside of the body, the tube thereby forming two ends both outside of the body, the one or more tube ports positionable proximate the interior area of the esophagus.

5. The device of claim 1, wherein the sleeve is slideable within the tube.

6. The device of claim 1, wherein the sleeve is slideable along an exterior of the tube.

7. The device of claim 1, further including a second tube connected to the flexible tube, the second tube configured with one or more openings, the second tube connectable to a source of negative pressure to aspirate fluid that has been released through aligned ports of the tube and sleeve.

8. The device of claim 1, further including an eluting extension which releases a therapeutic substance into the flexible tube, for release into the body through the flexible sleeve.

9. The device of claim 1, further including an eluting extension which is positioned outside of the flexible tube and sleeve, and which is contacted by liquid that has passed through the sleeve, to thereafter elute a therapeutic substance.

10. The device of claim 1, a distal end of the flexible tube that is passed first into the body being surrounded by an outer tube which captures liquid which has passed through the flexible sleeve.

11. The device of claim 1, a distal end of the flexible tube that is passed first into the body being surrounded by a balloon which captures liquid which has passed through the flexible sleeve.

12. The device of claim 11, further including a second tube connected to the flexible tube, the second tube configured with one or more openings, the second tube connectable to a source of negative pressure to aspirate fluid that has been released through aligned ports of the tube and sleeve.

13. The device of claim 1, the flexible tube formed into a coil.

14. The device of claim 1, wherein a steerable element is inserted into an interior of the flexible tube, the steerable element configured to be bent when positioned inside the body and in the interior of the flexible tube, to thereby cause a change in an orientation of the flexible tube within the body.

15. The device of claim 1, wherein the liquid further includes solids thereby forming a slurry.

16. The device of claim 1, wherein the liquid is a slurry containing at least one of a calcium carbonate, an acid reducing substance, an agent which reduces the formation of acid in the digestive tract.

17. The device of claim 1, wherein the liquid includes a substance which expands in the body to release a therapeutic substance.