WO2008074026A2

WO2008074026A2 - System and method to reshape annular organ with electrodes

Info

Publication number: WO2008074026A2
Application number: PCT/US2007/087501
Authority: WO
Inventors: Duane D. Dickens; John A. Osth; Thomas H. Witzel
Original assignee: Quantumcor, Inc.
Priority date: 2006-12-13
Filing date: 2007-12-13
Publication date: 2008-06-19
Also published as: WO2008074026A3

Abstract

System and method for repairing an annular organ structure of a heart valve, an annular organ structure of a venous valve, a valve leaflet, chordae tendinae, papillary muscles, a sphincter, and the like. May be deployed into the heart via a catheter percutaneously or via a cannula through a percutaneous intercostal penetration. Provides a tissue-shrinkable energy that may be applied to the target annular organ sufficient to treat the target organ structure. Reshaping collagen rich tissue through the emission or generation of heat or radiation within the tissue modifying the collagen through the process of denaturation. Provides tissue-shrinking energy to the valvular annulus of a beating heart without the interruption of blood flow through the valve.

Description

SYSTEM AND METHOD TO RESHAPE ANNULAR ORGAN WITH ELECTRODES

INVENTORS: Duane DICKENS

John OSTH Thomas WITZEL

This application claims benefit of United States Provisional Patent Application Serial No. 60/874,527, filed 12/13/2006, the specification of which is hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION FIELD OF THE INVENTION

[001] Embodiments of the invention described herein pertain to the field of medical devices and methods for treating annular organ structure. One or more embodiments of the invention enable a system and methods for applying therapeutic energy to a patient such as reducing and/or shrinking a tissue mass. More particularly, but not by way of limitation, one or more embodiments of the invention enable a catheter system that selectively contacts the tissue of a valvular annulus in order to tighten and stabilize an annular organ structure or adapted for repairing an annular organ structure defect of a patient.

DESCRIPTION OF THE RELATED ART

[002] Regurgitation (leakage) of the mitral valve or tricuspid valve can result from many different causes, such as an ischemic heart disease, myocardial infarction, acquired or inherited cardiomyopathy, congenital defect, myxomatous degeneration of valve tissue over time, traumatic injury, infectious disease, or various forms of heart disease. Primary-heart-muscle disease can cause valvular regurgitation through dilation, resulting in an expansion of the valvular annulus and leading to the malcoaptation of the valve leaflets through overstretching, degeneration, or rupture of the papillary-muscle apparatus, or through dysfunction or malpositioning of the papillary muscles. This regurgitation can cause heart irregularities, such as an irregular heart rhythm, and itself can cause inexorable deterioration in heart-muscle function. Such deterioration can be associated with functional impairment, congestive heart failure and significant pain, suffering, lessening of the quality of life, or even death. [003] Surgical options for correcting defects in the heart valves include repair or replacement of a valve, but these surgical options require open-heart surgery, which generally requires stopping the heart and cardiopulmonary bypass. Recovery from open-heart surgery can be very lengthy and painful, or even debilitating, since open-heart surgery requires pulling apart the ribs to expose the heart in the chest cavity. Cardiopulmonary bypass itself is associated with comorbidity, including cognitive decline. Additionally, open-heart surgery carries the risk of death, stroke, infection, phrenic-nerve injury, chronic-pain syndrome, venous thromboembolism, and other complications. In fact, a number of patients suffering heart-valve defects cannot undergo surgical-valve treatment because they are too weak or physiologically vulnerable to risk the operation. A still larger proportion of patients have mitral-valve regurgitation that is significant, but not sufficiently so to warrant the morbidity and mortality risk of cardiac surgery. If there were a less dangerous, even if less effective, minimally invasive system or method, more patients would likely undergo treatment for valvular regurgitation.

[004] Other surgical procedures have been provided to treat the mitral annulus using a less invasive surgical technique. According to one such technique, prosthesis is transvenously advanced into the coronary sinus and the prosthesis is deployed within the coronary sinus to reduce the diameter of the mitral annulus. This may be accomplished in an open procedure or by percutaneously accessing the venous system by one of the internal jugular subclavian or femoral veins. The prosthesis is tightened down within the coronary sinus which is located adjacent the mitral annulus, to reduce the mitral annulus. While the coronary sinus implant provides a less invasive treatment alternative, the placement of the prosthesis within the coronary sinus may be problematic for a number of reasons. Sometimes the coronary sinus is not accessible. The coronary sinus on a particular individual may not wrap around the heart far enough to allow enough encircling of the mitral valve. More specifically, the coronary sinus/great cardiac vein runs in the atrioventricular groove between the left atrium and left ventricle. The left circumflex artery originates from the left main coronary artery and courses within the atrioventricular groove. One to three large obtuse marginal branches extend from the left circumflex artery as it passes down the atrioventricular groove. These principal branches supply blood to (perfuse) the lateral free wall of the left ventricle. In approximately 15% of the population, the left circumflex artery is a dominant source of blood to the left posterior descending artery for perfusing and supporting the viability of the left ventricle. When the circumflex artery is superior to the coronary sinus, the obtuse marginal branches extending towards the ventricular wall may run either underneath the coronary sinus or above the coronary sinus. Hence, when placing a mitral valve therapy in the coronary sinus care must be taken to avoid occlusion of major arteries. Also, leaving a device in the coronary sinus may result in formation and breaking off of thrombus which may pass into the right atrium, right ventricle and ultimately the lungs causing a pulmonary embolism. Another disadvantage is that the coronary sinus is typically used for placement of a pacing lead, which may be precluded with the placement of the prosthesis in the coronary sinus.

[005] Many repair techniques that address valvular disease at the annular level in hopes that the valvular annulus will coapt. Attempts to decrease annular size, transplant chordae, or resect portions of the valvular annulus hope to create an architecture in which the valvular annulus will once again coapt have met with a limited success. The variability of the subvalvular apparatus and the numerous pathologies of, for example, mitral valve regurgitation often complicate appropriate repair technique selection. Malcoaptation of the valvular annulus is only indirectly addressed by various repair techniques.

[006] Collagen is the most abundant structural protein in the body, where it primarily serves a supportive function within the extracellular matrix. Type I collagen is the most common in ligaments, tendons and heart valves. Type I collagen is formed by three protein chains which are wound together to form a triple helical structure. The cross-linking of collagen molecules gives the structure a high tensile strength and stiffness. In its normal state collagen is "extended" in rod- like fibrils.

[007] Collagen molecules polymerize into chains in a head-to-tail arrangement generally with each adjacent chain overlapping another by about one-fourth the length of the helical domain. The spatial arrangement of the three peptide chains is unique to collagen, with each chain existing as a right-handed helical coil. The superstructure of the molecule is represented by the three chains that are twisted into a left-handed superhelix. The helical structure of each collagen molecule is bonded together by heat labile cross-links between the three peptide chains providing the molecule with unique physical properties, including high tensile strength and limited longitudinal elasticity.

[008] Therefore, there is a need to have a less surgically invasive therapy for repairing an annular organ structure of a heart valve, a valve leaflet, chordae tendonae, papillary muscles, and the like. BRIEF SUMMARY OF THE INVENTION

[009] One or more embodiments of the invention provide a system and method for repairing an annular organ structure of a heart valve, an annular organ structure of a venous valve, a valve leaflet, chordae tendinae, papillary muscles, a sphincter, and the like. In a minimally invasive surgical procedure, the system may be deployed into the heart via a catheter percutaneously or via a cannula through a percutaneous intercostal penetration.

[0010] In other embodiments, the system may be in a form of surgical hand-held apparatus during an open chest procedure. The system may be deployed into a sphincter via trans-thoracic or trans-abdominal approaches or via urogenital or gastrointestinal orifices. The system may be deployed into a venous valve using local surgical approaches or by percutaneous access into the venous system.

[0011] In the above embodiments, the invention provides a tissue-shrinkable energy that may be applied to the target annular organ sufficient to treat the target organ structure. The tissue- shrinkable energy may be cryogenic energy, radiofrequency energy, or high frequency current. In one or more embodiments of the invention, the system and method delivering a high frequency current may include but not limited to radiofrequency, focused ultrasound, infrared, or microwave energy, wherein the high frequent current is applied to the target organ structure.

[0012] Accordingly, one or more embodiments of the invention provide an apparatus for the application of tissue-shrinkable energy to an annular organ tissue site comprised of collagen. One or more embodiments of the invention provide a catheter-based minimally surgically invasive system that intimately contacts the tissue of an annulus in order to tighten and stabilize a substantial portion of the dysfunctional annular organ structure simultaneously or sequentially. The step of intimately contacting may be assisted by deployable structures at the distal segment of the device to position and stabilize the tissue-shrinkable energy-emitting elements relative to anatomic structures. The tissue-shrinkable energy elements may transmit an effective amount of the tissue shrinkable energy through a medium onto the target annulus in order to tighten and stabilize a substantial portion of the dysfunctional annular organ structure. The system may position a distal deployable structure at the comissures of an annular organ such as mitral heart valve annulus.

[0013] One or more embodiments of the invention provide a method for repairing a valvular annulus defect comprising positioning the distal segment of the apparatus in the left atrial appendage to stabilize the tissue-shrinkable energy-emitting elements about the annulus while applying effective tissue-shrinkable energy sufficient to treat the valvular annulus.

[0014] One or more embodiments of the invention provide an apparatus with a flexible tissue- contactor member located at the distal tip section of a catheter shaft for positioning a tissue- contactor member includes a pre-shaped structure having a plurality of tissue-shrinkable energy- emitting elements that are deployed about the valvular annulus.

[0015] One or more embodiments of the invention provide a method for reshaping collagen rich tissue through the emission or generation of heat or radiation within the tissue modifying the collagen through the process of denaturation. When tissue is subjected to, for example, elevated temperatures, the collagen bonds denature in a predictable manner causing immediate shrinkage of the collagen fibers resulting in tissue shrinkage. The method may include the monitoring and control of temperature at the tissue surface and within the tissue structure which is achieved through the use of suitable temperature sensors on or near the energy application site.

[0016] One or more embodiment of the invention provide a catheter system and methods for providing tissue-shrinkable energy in a form of high frequency current energy to a target tissue or adjacent to an annular organ structure. Such catheter system may be placed remotely from and/or non-contacting with the target tissue. In another embodiment, a catheter having a working distal end that may be covered by a plurality of adjacent filaments which are bound together by suturing, braiding, jacketing or encapsulating to provide a non-skid surface.

[0017] One or more embodiments of the invention to provide catheter system and methods for providing tissue-shrinking energy to the mitral valve annulus of a beating heart without the interruption of blood flow through the valve. In such embodiments, the apparatus is arranged in ways such that the blood flows through the valve being treated during the application of tissue- shrinkable energy.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of the invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein:

[0018] Figure 1 depicts an overall view of one embodiment of a catheter system having a flexible tissue-contactor member on the distal end fitted with energy-emitting elements for treating tissue.

[0019] Figure 2 illustrates a close-up of the distal tip section of one or more embodiment of the invention comprising a retracted tissue contactor members with a retracted central stabilizer element.

[0020] Figure 3 illustrates a close-up view of the deployed tip section of one or more embodiment of the invention as it is placed in the mitral valve annulus comprising a deployed central stabilizer and deployed tissue-contactor members with energy-emitting elements.

[0021] Figure 4 illustrates a close-up of the distal tip section of one embodiment comprised of an array of deployable energy-emitting elements and a distal balloon for stabilization in the atrial appendage.

[0022] Figure 5 illustrates a close-up of the distal tip of the embodiment described in FIG 4 in the un-deployed state.

[0023] Figure 6 depict an embodiment of FIG 4 with the distal tip positioned in the atrial appendage for stability and the loop of energy-emitting elements deployed from the distal tip section of the invention and placed about the valve annulus.

[0024] Figure 7 illustrates a cross-section of the distal tip section of one embodiment with a single array of energy-emitting elements in the deployed state.

[0025] Figure 8 illustrates a close-up of a typical energy-emitting element with temperature sensors on the element. DETAILED DESCRIPTION

[0026] A system and method for reshaping annular organ with tissue-shrinkable energy- emitting element will now be described. In the following exemplary description numerous specific details are set forth in order to provide a more thorough understanding of embodiments of the invention. It will be apparent, however, to an artisan of ordinary skill that the present invention may be practiced without incorporating all aspects of the specific details described herein. In other instances, specific features, quantities, or measurements well known to those of ordinary skill in the art have not been described in detail so as not to obscure the invention. Readers should note that although examples of the invention are set forth herein, the claims, and the full scope of any equivalents, are what define the metes and bounds of the invention.

[0027] In general, system comprises a catheter or similar probe having at least one energy- emitting element. The energy-emitting element may be any tissue-shrinkable energy source. Energy-emitting elements must be able to be turned on (activated) and off (deactivated), and/or modulated between high and low intensities. Typical energy-emitting element comprises a microwave-emitting element, a cryogenic-emitting element, a thermal-emitting element, a light- emitting element, an ultrasound transducer, a radio frequency-emitting element, or any combination thereof. Thermal-emitting element include, for example, electroresistive devices and infrared sources, among others. The element is connected to an energy source or generator that can be controlled to treat tissue or cause the tissue shrinkage.

[0028] One or more embodiments of the invention provide a system having one or a plurality of energy-emitting elements. The energy-emitting element may be mounted on a substrate in a defined spatial pattern, or array. As used herein, the term "array" refers to an arrangement of energy-emitting elements. The array may be a regular array, such as a line, a series of column and rows, or a spiral, or a random array.

[0029] As used herein, the term "tissue-shrinkable energy" is intended to describe any energy that causes geometrical modification of tissue or cause tissue to shrink of its original dimension. The tissue-shrinkable energy may also be useful as a stimulant for inducing a biologic repair process in a way that treated tissue becomes more resilient. The tissue-shrinkable energy is in term provided by energy-emitting element. In some embodiment, the tissue-shrinkable energy is infrared energy, ultrasound energy, radiofrequency energy, microwave energy, electromagnetic energy, laser energy, or the like. [0030] When a tissue-shrinkable energy such as moderate thermal energy, not ablation, is applied to, for example, a collagen molecule, the hydrogen bonds that hold the collagen molecule together are disrupted but the strong intermolecular bonds remain intact. The collagen collapses into random coils and the tissue shrinks or tightens during this energy-induced modification of the collagen. The result is a partial recovery or recreation of the mechanical properties of collagenous tissue. Therefore, one or more embodiments of the invention treat an annular organ structure by shrinking/tightening techniques through the application of tissue-shrinkable energy.

[0031] For monitoring local tissue temperature fluctuation, one or a plurality of temperature sensors may be adapted, coupled or integrated with one or more energy-emitting elements, or alternatively adapted or coupled to the tissue-contactor member. The temperature sensor allows for monitoring of local tissue temperature to guard against over heating of tissue. A temperature sensor may incorporate one or more temperature-sensing elements such as, for example, semiconductor-based sensors, thermisters, thermocouples, or fiber optic temperature sensors. Miniature temperature sensors known to one of ordinary skill in the art and suitable for this particular in vivo application may also be used.

[0032] An independent temperature monitor may be connected to the temperature sensor. A closed-loop control mechanism, such as a feedback controller with a microprocessor or a temperature controller, may be implemented for controlling the delivery of tissue-shrinkable energy to the target tissue based on temperature measured by the temperature sensor. Alternatively, an energy source with an integrated temperature monitoring circuit may be used to control the tissue-shrinkable energy power output supplied to the energy-emitting element.

[0033] The amount of tissue shrinkable energy as emitted by energy-emitting element is the amount effective to tighten and shrink tissue and not to cause any adverse impact on the mechanical properties of collagenous tissue. The temperature to tighten and shrink, for example, a collagenous tissue within a range of 50 to about 70° C. for a short period of time. The heat labile cross-links of collagen may be broken by thermal effects, thus causing the helical structure of the molecule to be destroyed (or denatured) with the peptide chains separating into individually randomly coiled structures of significantly lesser length. The thermal cleaving of such cross-links may result in contraction or shrinkage of the collagen molecule along its longitudinal axis by as much as one-third of its original dimension. It is such shrinkage of collagenous tissue that may effect a partial recovery or recreation of the mechanical properties of collagenous tissue.

[0034] Collagen shrinks within a specific temperature range, (e.g., 50° C. to 70° C. depending on its type), which range has been variously defined as: the temperature at which a helical structure collagen molecule is denatured; the temperature at which 1/2 of the helical superstructure is lost; or the temperature at which the collagen shrinkage is greatest. In fact, the concept of a single collagen shrinkage temperature is less than meaningful, because shrinkage or denaturation of collagen depends not only on an actual peak temperature, also on a temperature increase profile (increase in temperature at a particular rate and maintenance at a particular temperature over a period of time). For example, collagen shrinkage can be attained through high-energy exposure (energy density) for a very short period of time to attain "instantaneous" collagen shrinkage (e.g., 1-2 seconds). Longer time intervals between deliveries of tissue shrinkable energy allow slower rate of collagen shrinkage, affording the surgeon sufficient time to evaluate the extent of tissue shrinkage and to terminate tissue shrinkable energy delivery based on observation. Using the apparatus and methods of the present invention, the surgeon simply may terminate the power to energy-emitting element at any time during tissue shrinkage to gauge the correct amount of shrinkage.

[0035] FIG 1 illustrates an overall view of an embodiment of the catheter-based treatment system having a flexible tissue-contactor member and a tissue-shrinkable energy-emitting element at its distal tip section constructed in accordance with the principles of the invention. The catheter system comprises a flexible catheter shaft 1 having a distal tip section 2, a distal end 3, a proximal end 4, and at least one lumen 20 extending therebetween. As shown in FIG. 1, elongated catheter shaft 1 preferably is sufficiently flexible to twist about its longitudinal axis. In addition, elongated member may comprise a resilient material capable of being springably formed to either a repose curved or linear configuration.

[0036] In one embodiment, the catheter system comprises a flexible, relatively semi-rigid tissue- contactor member 5 and a pre-shaped stabilizer member 6 located at the distal tip section 2 and inside the at least one lumen 20 of the catheter shaft 1 for contacting an inner wall of an annular organ structure when deployed. The tissue-contactor members may have certain variations (72 in FIG. 4 and 81 in FIG. 7) for contacting the inner wall of the annular organ structure for applying tissue-shrinkable energy site-specifically.

[0037] The tissue-contactor member 5 is deployable out of the at least one lumen 20 by a tissue- contactor deployment mechanism 14 located at a handle 13. The tissue-contactor member 5 is preformed or expandable to have an approximate shape configured to fit with the inner wall of the annular organ structure. The tissue-contactor member 5 may be a circular ring or any other round shaped construct. The tissue-contactor member 5 is configured with an array having a plurality of energy emitting element means 21. [0038] The stabilizer member 6 is deployable out of the at least one lumen 20 by a stabilizer member deployment mechanism 15 located at a handle 13. The stabilizer member 6 is configured to retain or prop open valvular leaflet of the annular organ structure. As shown in FIG. 1, the stabilizer member 6 has two commissure notches 7.

[0039] The handle 13 is attached to the proximal end 4 of the catheter shaft 1. The handle comprises the tissue-contactor deployment mechanism 14 for advancing the tissue-contactor member 5 with an array of energy-emitting element means. The electrode element means are intended for shrinking tissue of annular organ structure.

[0040] A connector 16 secured at the proximal end of the catheter system, is part of the handle section 13. The handle 13 has one optional steering mechanism 10. The steering mechanism 10 is to deflect the distal tip section 2 of the catheter shaft 1 for catheter maneuvering and positioning. In at least one embodiment, by pushing forward the front plunger 11 of the handle 13, the distal tip section 2 of the catheter shaft deflects to one direction. By pulling back the front plunger 11, the tip section returns to its neutral position. In another embodiment, the steering mechanism 10, at the handle 13 comprises means for providing a plurality of deflectable curves on the distal tip section 2 of the catheter shaft 1.

[0041] In one embodiment of high frequency treatment, the catheter system also comprises an energy source such as a high frequency current generator 60, wherein an electrical conductor means 61 for transmitting current to the energy-emitting element means such as electrodes (21 in FIG. 2, 21 in FIG. 4 or 21 in FIG. 8) on a flexible tissue-contactor member is provided. One or more embodiments of the invention provides tissue-shrinkable energy such as a high frequency heat to collagen of tissue to a temperature range of about 45° C. to 75° C. or higher for at least a few seconds to cause collagen to shrink a fraction of its original dimension. The energy required from the high frequency current generator is generally less than 100 watts, typically less than 30 watts.

[0042] In one embodiment, the method may comprise percutaneously introducing the catheter system through a blood vessel to a site of the valvular annulus or introducing the catheter system through a thoroscopy port into a heart or during an open-heart surgery. For other applications such as the sphincter treatment, the catheter may be introduced through a natural opening of the body. The application for sphincter treatment of the present invention comprises esophageal sphincter, urinary sphincter or the like. Small, ring-like muscles, called sphincters, surround portions of the alimentary canal. In a healthy person, these muscles contract or tighten in a coordinated fashion during eating and the ensuing digestive process, to temporarily close off one region of the alimentary canal from another.

[0043] For example, a muscular ring called the lower esophageal sphincter surrounds the opening between the esophagus and the stomach. The lower esophageal sphincter is a ring of increased thickness in the circular, smooth-muscle layer of the esophagus. Normally, the lower esophageal sphincter maintains a high-pressure zone between fifteen and thirty mm Hg above intragastric pressures inside the stomach. The catheter system and methods of the present invention may suitably apply to repair a sphincter annulus, other than the esophageal sphincter, in a patient.

[0044] FIG. 2 shows a close-up view of the distal tip section 2 of the catheter system including a pair of retracted tissue-contactor member 5 and a retracted stabilizer member 6 at a non-deployed state. Both pair of tissue-contactor members and stabilizer member are retractable to stay within the at least one lumen 20. This non-deployed state is used for a catheter to enter into and to withdraw from the body of a patient. The tissue-contactor member is generally preformed or constricted and flexible enough so that it can easily be retracted into the catheter lumen 20. The tissue-contactor member 5 is shown with an array of energy-emitting element means 21.

[0045] The tissue-contactor member 5 may be made of a biocompatible material selected from the group consisting of silicone, latex, polyurethane, fluoro-elastomer, polypropylene, polyethylene, polyethylene terephthalate, nylon, and a combination thereof. Reinforced substrate, such as mesh, wire, fiber, and the like, may be added to the tissue-contactor member 5 to make the tissue-contactor member semi-rigid so that when it is deployed, adequate pressure is exerted to the surrounding tissue for stabilizing its placement.

[0046] The embodiments of the stabilizer member described herein can also be constructed of one or more of a number of materials and in a variety of configurations. The stabilizer member 6 may include a coil spring tip 22. Great flexibility is provided by the coil spring tip 22 to enable relative motion of the stabilizer member 6 upon contact with a tissue or wall. The amount of flexibility is selected as in any spring by varying the material, cross-sectional size and shape, and number of turns of the spring. The stabilizer frame embodiments of the stabilizer member 6 can have a unitary structure with an open stabilizer configuration. The stabilizer can also be self- expanding. Examples of self-expanding stabilizers include those formed from temperature- sensitive memory alloy which changes shape at a designated temperature or temperature range, such as Nitinol. Alternatively, the self-expanding stabilizers can include those having a spring- bias. [0047] The embodiments of the stabilizer, such as stabilizer 6 in FIG. 1, can also be formed from one or more contiguous stabilizer members. For example, the stabilizer member 6 of stabilizer frame embodiments can be a single contiguous member. The single contiguous member can be bent around an elongate tubular mandrel to form the stabilizer. The free ends of the single contiguous member can then be welded, fused, crimped, or otherwise joined together to form the stabilizer. In an additional embodiment, the stabilizer member 6 of stabilizer frame can be derived (e.g., laser cut, water cut) from a single tubular segment. In an alternative embodiment, methods of joining the stabilizer member 6 to create the elastic region include, but are not limited to, welding, gluing, and fusing the stabilizer member. The stabilizer frame can be heat set by a method as is typically known for the material which forms the stabilizer frame.

[0048] The stabilizer embodiments can be formed from a number of materials. For example, the stabilizer can be formed from a biocompatible metal, metal alloy, polymeric material, or combination thereof. Examples of suitable materials include, but are not limited to, medical grade stainless steel (e.g., 316L), titanium, tantalum, platinum alloys, niobium alloys, cobalt alloys, alginate, or combinations thereof. Additional stabilizer embodiments can be formed from a shape-memory material, such as shape memory plastics, polymers, and thermoplastic materials. Shaped memory alloys having superelastic properties generally made from ratios of nickel and titanium, commonly known as Nitinol, are typical materials. Other materials are also possible.

[0049] In the embodiment as shown in FIGs. 2 and 3, distal end of the catheter shaft 1 may be surrounded by a radioplague marker band 23 to aid in fluoroscopic observation during manipulation of catheter through the body of a patient or patient's vasculature.

[0050] FIG. 3 shows a simulated view of the distal tip section 2 of one embodiment of the catheter system comprising a pair of deployed tissue-contactor member 5 and a deployed stabilizer member 6 in contact with the tissue of an annular organ structure, in this case, a mitral valve. Left atrium of the heart communicates with the left ventricle through the mitral valve. In a perspective illustration, a catheter is inserted into the left atrium and the pair of tissue-contactor members 5 are positioned on the inner wall of the mitral valve. The leaflets of the mitral valve is propped open and rested on the commissure notches 7 of the deployed stabilizer member 6. Blood flows from the left atrium to the left ventricle through the mitral valve. When stabilizer member is not deployed out of the lumen, the deployed tissue-contactor member 5 of the catheter shaft 1 does not interfere with the leaflet movement during the less invasive treatment of the invention. [0051] The tissue of the heart valve in the treatment procedures may be selected from the group consisting of valvular annulus, chordae tendinae 100, valve leaflet, and papillary muscles 101. In the embodiments using the high frequency current in the treatment procedures may be selected from the group consisting of radiofrequency current, microwave current, ultrasound current, and combination thereof.

[0052] FIG. 4 shows one embodiment of a catheter system in a deployed state having a flexible semi-rigid tissue contactor member 70 advanced by guide wire 71 from the at least one lumen of the catheter shaft 1 and an alternative distal tip section 72 with an expanded inflatable member 73 and coil spring tip 22. The tissue-contactor member 70 may comprise a plurality of energy- emitting element means 21, wherein the energy- emitting element means may be grouped for performing various modes of energy delivery selected from the group consisting of individual mode, pulsed mode, programmed mode, simultaneous mode, or combination thereof. The energy emitting element means 21 may be made of flexible conductive elastomer material or flexible metal-containing conductive elastomer material selected from the group consisting of silicone, latex, polyurethane, fluoro-elastomer, nylon, and a combination thereof. The energy-emitting element means normally are securely bonded to the surface of the substrate at appropriate locations so that each electrode becomes an integral part of the general tissue-contractor member 35.

[0053] FIG. 5 shows one embodiment of a catheter system in an un-deployed sate having a flexible semi-rigid tissue contactor member hidden inside the catheter shaft 1 with guide wire 71 exposed from the at least one lumen of the catheter shaft 1 and an alternative distal tip section 72 with a collapsed inflatable member 73 and coil spring tip 22.

[0054] The techniques to inflate and deflate an inflatable member 73 through a port 74 by infusing physiologic liquid through the liquid passageway inside a lumen are well known to one who is skilled in the art and do not form a part of the present invention. Other types of inflatable members, such as double-balloon, porous balloon, microporous balloon, channel balloon or the like that meet the principles of the present invention may be equally herein applicable.

[0055] Referring to FIG. 6, a catheter system is shown deployed with a tissue contactor member 5 about the heart annulus with an inflatable member 73 positioned against the atrial wall for stability.

[0056] One advantage of the current embodiment as shown in FIGs. 4, 5 and 6 is to provide physiologic liquid to inflate an inflatable member for repairing the valvular defect, whereas the liquid in the inflatable member serves as a heat sink to dissipate the heat generated from the energy-emitting element means contacting the tissue. By continuously diverting the excess heat from the energy-emitting element means-tissue contact site, the treatment efficiency can be substantially enhanced to cause quality desired shrinkage or tightening of the tissue of the annulus. The requirement for the high frequency power can therefore be significantly reduced. The energy required from the high frequency current generator is generally less than 100 watts in tissue ablation, typically less than 10 watts because of the heat-dissipating embodiment of the present invention for repairing an annulus.

[0057] Referring to Figure 7, an alternative distal section is shown for a catheter system which includes a single preformed tissue-contactor member 5 with an array of energy-emitting element means and a central stabilizer 80 featuring independent commissural registration elements 81 and rounded tips 82.

[0058] FIG. 8 illustrates a typical energy-emitting element mean 21 fitted with temperature sensors 52 (e.g., a thermocouple type, a thermister type, or any miniature temperature sensor known to one of ordinary skills in the relevant art) which are coupled via temperature sensing wires 51 with the temperature controller 50 of FIG. 1 and an electrical conductor means 61 of connecting the energy-emitting element mean to an energy source 60 of FIG. 1. The temperature sensing wire 51 from the temperature sensor 52 is connected to one of the contact pins of the connector 16 and externally connected to a transducer and to a temperature controller 50. The temperature reading is thereafter relayed to a closed-loop control mechanism to adjust the tissue- shrinkable energy output such as high frequency energy. The high frequency energy delivered is thus controlled by the temperature sensor reading or by a pre-programmed control algorithm.

[0059] While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.

Claims

CLAIMSWhat is claimed is:

1. A device configured for shrinking an annular organ structure of the body, having an electrical conductor mean for connection to an energy source and a distal end adapted for delivering tissue- shrinkable energy to said annular organ structure, wherein said device comprising:

(a) An elongated catheter shaft defined with at least one lumen having a distal segment with energy-emitting elements and said proximal end with a handle and means for connecting to an energy source;

(b) at least one temperature sensor at an energy-emitting element means adapted for measuring temperature of a inner wall of said annular organ structure;

(c) a mean of stabilizing the distal section of the device through preformed structural configurations that are appropriately shaped to be positioned within or about anatomic structures within the body;

(d) said tissue contacting member containing a plurality of energy-emitting element means coupled with said energy source;

(e) pre-shaped stablizer members slidably disposed within said distal section for stabilizing said distal portion; and,

(f) optionally an inflatable member.