30 results about "Linear ablation" patented technology

This invention is a circumferential ablation device assembly which is adapted to forming a circumferential conduction block in a pulmonary vein. The assembly includes a circumferential ablation element which is adapted to ablate a circumferential region of tissue along a pulmonary vein wall which circumscribes the pulmonary vein lumen, thereby transecting the electrical conductivity of the pulmonary vein against conduction along its longitudinal axis and into the left atrium. The circumferential ablation element includes an expandable member with a working length that is adjustable from a radially collapsed position to a radially expanded position. An equatorial band circumscribes the outer surface of the working length and is adapted to ablate tissue adjacent thereto when actuated by an ablation actuator. The equatorial band has a length relative to the longitudinal axis of the expandable member that is narrow relative to the working length, and is also substantially shorter than its circumference when the working length is in the radially expanded position. A pattern of insulators may be included over an ablation element which otherwise spans the working length in order to form the equatorial band described. The expandable member is also adapted to conform to the pulmonary vein in the region of its ostium, such as by providing a great deal of radial compliance or by providing a taper along the working length which has a distally reducing outer diameter. A linear ablation element is provided adjacent to the circumferential ablation element in a combination assembly which is adapted for use in a less-invasive “maze”-type procedure in the region of the pulmonary vein ostia in the left ventricle.

This invention is a circumferential ablation device assembly which is adapted to forming a circumferential conduction block in a pulmonary vein. The assembly includes a circumferential ablation element which is adapted to ablate a circumferential region of tissue along a pulmonary vein wall which circumscribes the pulmonary vein lumen, thereby transecting the electrical conductivity of the pulmonary vein against conduction along its longitudinal axis and into the left atrium. The circumferential ablation element includes an expandable member with a working length that is adjustable from a radially collapsed position to a radially expanded position. An equatorial band circumscribes the outer surface of the working length and is adapted to ablate tissue adjacent thereto when actuated by an ablation actuator. The equatorial band has a length relative to the longitudinal axis of the expandable member that is narrow relative to the working length, and is also substantially shorter than its circumference when the working length is in the radially expanded position. A pattern of insulators may be included over an ablation element which otherwise spans the working length in order to form the equatorial band described. The expandable member is also adapted to conform to the pulmonary vein in the region of its ostium, such as by providing a great deal of radial compliance or by providing a taper along the working length which has a distally reducing outer diameter. A linear ablation element is provided adjacent to the circumferential ablation element in a combination assembly which is adapted for use in a less-invasive “maze”-type procedure in the region of the pulmonary vein ostia in the left ventricle.

An intravascular device for the formation of linear lesions which has particular utility in the treatment of atrial fibrillation and flutter. The intravascular device has an outer delivery member with a distal section which has an elongated opening and a support element coextending with the opening. An EP device having a plurality of electrodes on its distal section is slidably disposed within the inner lumen of the delivery member but it is secured by its distal end within the distal extremity of the delivery member at least while in operation. In this manner an axial force in the proximal direction on the proximal extremity of the EP device, which extends out of the patient during the procedure, will cause the distal shaft section of the EP device to arch outwardly out of and away from the distal section of the delivery shaft along an inner side of the curved distal section and engage the surface of the patient's heart chamber. RF electrical energy delivered to the electrodes on the distal shaft section of the EP device will form a linear lesion which terminates the fibrillation or flutter.

An ablation device for cardiac tissue, especially for forming a circular lesion around a vessel orifice in the heart, comprises a steerable catheter that is provided in the region of its distal end with an abutment device for holding the distal end of the catheter on a cardiac vessel orifice; and a linear ablation applicator that is disposed distally or proximally relative to the abutment device of the catheter and can be brought from a straight passive position into a radially expanded, approximately circular-arc-type encircling ablation position.

A catheter is provided with an anchoring member for anchoring a part of a linear ablating head of the catheter to a structure. The structure can be a cryogenically anchored point catheter. This allows the surgeon to position the linear catheter more exactly in the heart chamber and overcomes the adverse effects of the slippery and irregular heart chamber walls.

A delivery catheter having a shaft with a distal end and a proximal end for delivering an ablation probe to a body site. The delivery catheter comprises mounting members located at the distal end configured to receive an ablation probe; and attachment members configured to attach the distal end to a tissue surface. The delivery catheter preferably configured to allow an ablation probe mounted on the distal end to be manipulated so as to extend from the distal end in a direction selected from a range of directions. Even more preferably, the delivery catheter is configured to allow an ablation probe mounted on the distal end to be manipulated so as to move along a tissue surface and perform linear ablation. The invention also provides a system comprising the delivery catheter of the invention and an ablation device having an ablation probe, wherein the delivery catheter and the ablation probe are configured to allow the ablation probe to be mounted at the distal end of the delivery catheter.

An ablation device for cardiac tissue, especially for forming a circular lesion around a vessel orifice in the heart, comprises a steerable catheter that is provided in the region of its distal end with an abutment device for holding the distal end of the catheter on a cardiac vessel orifice; and a linear ablation applicator that is disposed distally or proximally relative to the abutment device of the catheter and can be brought from a straight passive position into a radially expanded, approximately circular-arc-type encircling ablation position.

The invention relates to a metal sputtering thin film technology-based ablation sensor. The metal sputtering thin film technology-based ablation sensor includes a shell with an ablation sensor sensitive assembly arranged therein; the ablation sensor sensitive assembly is composed of a metal wire grid, a substrate material and leads; the metal wire grid is plated on the substrate material through a metal sputtering thin film technology; one end of each lead is connected with the metal wire grid, and the other ends of the lead extend out from the shell, so that the signals of the metal wire grid can be transmitted to a conditioning module; and a filler is arranged between the shell and the ablation sensor sensitive assembly in a plugging manner. With the metal sputtering thin film technology-based ablation sensor of the invention adopted, real-time and on-line measurement of the linear ablation amount of a C / C composite material can be realized. According to the metal sputtering thin film technology-based ablation sensor, the magnitude of the output signals of the sensor is in direct proportion to the change of the linear ablation amount of the C / C composite material. The metal sputtering thin film technology-based ablation sensor has the advantages of high resolution and high measurement precision, and just lightly damages the body of a measured material.

A catheter is provided with an anchoring member for anchoring a part of a linear ablating head of the catheter to a structure. The structure can be a cryogenically anchored point catheter. This allows the surgeon to position the linear catheter more exactly in the heart chamber and overcomes the adverse effects of the slippery and irregular heart chamber walls.

A non-linear ablation device includes two opposing surfaces, which are associated with two overlying and separate compartments. A first compartment of the two overlying and separate compartments is configured to emit or resorb energy. A second compartment of the two overlying and separate compartments is configured to either resorb or emit energy to oppose a direction of energy transfer of the first compartment. Other embodiments of the non-linear ablation device are further disclosed.

The present application discloses an ablation device and system for treating atrial fibrillation, and a fixed pathway for ablation of persistent AF. The pathway consists of bilateral circumferential pulmonary sinus isolation ('2C') and three linear ablation groups ('3L'). The ablation device and system and the fixed pathway have the advantages of less radio frequency delivery, low X-ray irradiation frequency, and shorter time spent when used in surgery.

This invention relates to a method for preparing ZrB2-ZrC-SiC multiphase ceramic at ultrahigh temperatures with near-zero ablation. The ZrB2-ZrC-SiC multiphase ceramic is prepared from: ZrB2 50-75 wt.%, ZrC 15-40 wt.%, SiC 10-20 wt.%, and ZrO2 as the combustion aid 6-16 wt.%. The ZrB2-ZrC-SiC multiphase ceramic has synergistic effects at high temperatures, which can result in good high-temperature properties. The ZrB2-ZrC-SiC multiphase ceramic has a room-temperature bending strength of 300-400 MPa, a Rockwell hardness of 88-92, and a linear ablation of 0.0003-0.001 mm / s. The ZrB2-ZrC-SiC multiphase ceramic has better oxidation resistance, better ablation resistance and lower sintering temperature compared with single phase ceramics, and has such advantages as good applicability, even distribution, no limit to product shapes and little shape change after 2400 s oxygen-ethylene combustion at 2800-3200 deg.C.

The invention discloses a standard substance for calibration of a plasma ablation tester and a preparation method thereof, and belongs to the technical field of measurement. The standard substance forcalibration of the plasma ablation tester is prepared from a composite material prepared from carbon fiber with the length being (6+ / -2) mm and S157 effective phenolic resin at the mass ratio being 1:(3.8-4.2), the standard substance is shaped like a circular block, the linear ablation rate is 0.484+ / -0.030 mm / s. The standard substance has the advantages of being uniform in stability, accurate and reliable in setting and the like, and is suitable for verification and calibration of the plasma ablation tester, and the preparation method is good in repeatability and convenient to operate.

The invention discloses an ablation-resisting composite material resin composition and a preparation method of an ablation-resisting composite material, belonging to the field of high polymer composite material preparation. The composition comprises phenolic resin, poly(bisphenoxy)phosphazene, a coupling agent and silicon oil. The preparation method of the composite material comprises the following steps: respectively dissolving poly(bisphenoxy)phosphazene and the phenolic resin in tetrahydrofuran for complete dissolution, mixing to form a homogeneous solution, then coating the solution on carbon fiber cloth, and drying the carbon fiber cloth in a vacuum oven for 12 hours at the temperature of 50 DEG C after airing; and cutting the fiber cloth into square blocks and overlapping the squareblocks in a mould, heating for 1 hour at the temperature of 100 DEG C so as to completely melt boron phenolic resin, then heating to 120 DEG C to carry out procuring for 1 hour, finally heating to 180 DEG C and curing for 6 hours at the pressure of 5MPa, taking out and cooling to room temperature so as to prepare the ablation-resisting composite material. The composite material has the advantagesof higher flexural modulus and thermal deformation temperature as well as lower linear ablation rate and quality ablation rate; and the ablation resistance of the composite material is improved.

The invention belongs to the technical field of medical electronics, in particular to an adjustable radio frequency phase difference power amplifying circuit for realizing linear ablation. The circuit structure of the invention includes: a phase control unit, a radio frequency amplitude control unit, a radio frequency resonance and filter circuit, and an impedance matching network. Among them, the impedance matching network is used to make the myocardial impedance changing during the ablation process equivalent to the rated load range of the circuit, reduce the internal loss of the circuit, and stabilize the output frequency; the soft switching technology is used to make the electronic switch tube realize zero-voltage turn-on or zero-voltage derivative Turn on, reduce switching loss and improve work efficiency. This circuit can overcome the shortcomings of the traditional point-by-point discrete radio frequency ablation technology that it is difficult to form continuous ablation lesions. By adjusting the phase difference of the radio frequency output voltage of adjacent ablation electrodes, the effect of continuous linear ablation can be produced, thereby realizing continuous linear ablation of myocardial tissue.