Abstract: An ablation method and device contacts one surface of a target layer and positions the tissue to ablate entirely through the layer. The tissue may be a wall of the heart (ablated, for example, to form blocking lesions for atrial fibrillation), and ablation may be performed with the heart stopped or beating, and effected by either endocardial or epicardial contact. Access may be through an open incision or a minimally invasive technique involving a small opening through which one or more elongated surgical tools are inserted. Illustratively, an atrial ablation treatment can be performed prophylactically (after CABG), or independently to treat an existing condition. A tool of the present invention has a handle at a proximal end, a bipolar ablation head, and an elongated body interconnecting the handle and the ablation head.

Abstract: Ablation systems and methods for treating atrial fibrillation utilizing RF energy are provided. The system generally includes a first conductive member having a shape which defines a desired lesion pattern or a portion of a desired lesion pattern, and a second conductive member effective to transmit ablative radiation to the first conductive member. The first conductive member is adapted to be positioned on a first tissue surface, and the second conductive member is adapted to be positioned on a second, opposed tissue surface. In use, ablative radiation is transmitted from the second conductive member through the tissue to the first conductive member to form a lesion having the desired lesion pattern.

Abstract: A surgical device for severing tissue, the surgical device comprising; a first shaft having a first internal lumen and a first slot disposed at a distal end; a clamp slidingly disposed in the first slot between open and closed positions to capture tissue in the first slot, the clamp having a clamping surface disposed at a distal end; at least one electrode for applying RF energy to the tissue captured in the first slot; a cutting blade slidingly disposed in the first slot between open and closed positions, the cutting blade having a cutting edge to sever the tissue; first actuation means for actuating the clamp between the open and closed positions; and second actuation means for actuating the cutting blade between the open and closed positions.

Abstract: Ablation systems and methods for treating atrial fibrillation utilizing RF energy are provided. The system generally includes a first conductive member having a shape which defines a desired lesion pattern or a portion of a desired lesion pattern, and a second conductive member effective to transmit ablative radiation to the first conductive member. The first conductive member is adapted to be positioned on a first tissue surface, and the second conductive member is adapted to be positioned on a second, opposed tissue surface. In use, ablative radiation is transmitted from the second conductive member through the tissue to the first conductive member to form a lesion having the desired lesion pattern.

Abstract: An ablation method and device contacts one surface of a target layer and positions the tissue to ablate entirely through the layer. The tissue may be a wall of the heart (ablated, for example, to form blocking lesions for atrial fibrillation), and ablation may be performed with the heart stopped or beating, and effected by either endocardial or epicardial contact. Access may be through an open incision or a minimally invasive technique involving a small opening through which one or more elongated surgical tools are inserted. Illustratively, an atrial ablation treatment can be performed prophylactically (after CABG), or independently to treat an existing condition. A tool of the present invention has a handle at a proximal end, a bipolar ablation head, and an elongated body interconnecting the handle and the ablation head.

Abstract: The present invention provides a mechanism by which the physical properties of diseased blood vessel walls can be manipulated to achieve an effective vessel lumen diameter for a prolonged period of time. The methods and devices of the present invention selectively isolate and treat the medial or adventitial layers of these diseased blood vessels. The invention is based on the delivery of proteolytic enzymes and crosslinking agents via specialized delivery devices to a select layer of the diseased blood vessel wall. By isolating and treating these layers of the artery, collagen degrading and collagen crosslinking agents can be delivered so as to affect the diameter of the blood vessels and control blood flow therein.

Abstract: Ablation systems and methods for treating atrial fibrillation utilizing RF energy are provided. The system generally includes a first conductive member having a shape which defines a desired lesion pattern or a portion of a desired lesion pattern, and a second conductive member effective to transmit ablative radiation to the first conductive member. The first conductive member is adapted to be positioned on a first tissue surface, and the second conductive member is adapted to be positioned on a second, opposed tissue surface. In use, ablative radiation is transmitted from the second conductive member through the tissue to the first conductive member to form a lesion having the desired lesion pattern.

Abstract: A method of forming a lesion at a predetermined heart location is provided. An energy-delivering electrode is positioned proximal to the predetermined heart location; a return electrode is positioned in contact with cardiac tissue. An electrosurgical current, capable of delivering energy through the energy-delivering electrode to the predetermined heart location at a magnitude and for a duration effective to form a lesion is established. A system for treating atrial fibrillation by forming transmural lesions and a heart-positioning device including a return electrode are also provided. In one embodiment, one of the electrodes includes at least a portion that is selectively movable between a first, retracted position in which the electrode is adapted to be deployed through tissue, and a second, expanded position in which the electrode is adapted to be placed within a chamber of a heart.

Abstract: A method of forming a lesion at a predetermined heart location is provided. An energy-delivering electrode is positioned proximal to the predetermined heart location; a return electrode is positioned in contact with cardiac tissue. An electrosurgical current, capable of delivering energy through the energy-delivering electrode to the predetermined heart location at a magnitude and for a duration effective to form a lesion is established. A system for treating atrial fibrillation by forming transmural lesions and a heart-positioning device including a return electrode are also provided.

Abstract: Ablation instruments and methods for ablating tissue, and more particularly for treating atrial fibrillation utilizing RF energy are provided. The ablation instrument generally includes two components: a first member adapted to be placed on or adjacent to a first tissue surface, and a second member opposed to the first member and adapted to be placed on or adjacent to a second, opposed tissue surface. Each member includes a conductive element disposed on a portion thereof that is effective to communicate with a source of ablative energy. First and second conductor elements can be provided for transmitting ablative energy from an energy source to the first and second conductive elements. In use, ablative radiation is transmitted between the first and second members through the intervening tissue to form a lesion in the tissue.

Abstract: A surgical device for severing tissue, the surgical device comprising; a first shaft having a first internal lumen and a first slot disposed at a distal end; a clamp slidingly disposed in the first slot between open and closed positions to capture tissue in the first slot, the clamp having a clamping surface disposed at a distal end; at least one electrode for applying RF energy to the tissue captured in the first slot; a cutting blade slidingly disposed in the first slot between open and closed positions, the cutting blade having a cutting edge to sever the tissue; first actuation means for actuating the clamp between the open and closed positions; and second actuation means for actuating the cutting blade between the open and closed positions.

Abstract: A surgical device including: a first shaft having a first projection radially offset from an axial direction of the first shaft, the first projection having a first clamping surface; a second shaft slidably disposed relative to the first shaft, the second shaft having a second projection radially offset from the axial direction, the second projection having a second clamping surface; a dissector for dissecting tissue from a blood vessel to be harvested; a first actuator for sliding the second projection relative to the first projection to capture a side branch of the vessel between the first and second clamping surfaces; at least one electrode for applying cauterizing energy to cauterize the captured side branch; a cutting blade movably disposed on one of the first or second projections; and a second actuator for moving the cutting blade to sever the side branch captured between the first and second projections.

Abstract: The present invention relates to methods and apparatuses for characterization of single polymers. In particular, the invention relates to methods and apparatuses for determination of the velocities of single elongated polymers. Center-of-mass velocity, center-to-center velocity, end-to-end velocity and rise-time velocity are determined using time-correlated measurements of single elongated polymers in two or more detection zones. The invention also relates to methods of determinating lengths and molecular masses of single polymers and to methods of determining the distance between landmarks on a single polymers based on their velocities. The invention further relates to methods of single-molecule DNA restriction fragment analysis.

Abstract: A method for determining the length and velocity of single elongated macromolecules is disclosed. In particular, the present invention relates to methods and apparatus for determining the velocity of elongated polymeric molecules moving relative to one or more detection stations, as well as to methods and apparatus for determining the length of such molecules and the distance between landmarks that may be present on such molecules. The invention makes use of time correlated measurements of signal amplitude profiles that result from interactions between each detection station and portions of each macromolecule.

Abstract: An improved fluid pressure sensor/sensor array is shown to provide high resolution, sensitivity which can be easily controlled based on anticipated or detected pressure range, and reliable pressure measurements with easy installation and low fabrication cost. A fluid pressure sensor is provided having a substantially incompressible mounting structure with a cavity formed therein. An elastic membrane is attached to said mounting structure and across said cavity, separating the cavity from the fluid to be measured. At least one non-contact transducer is attached to the mounting structure in the cavity to detect deflection at a selected plurality of regions on the membrane. The sensitivity and pressure range of the sensor can be chosen by preselecting the elasticity of the membrane, stretching the membrane across the cavity under a preselected tension, maintaining a predetermined reference pressure in the cavity, and/or actively controlling the membrane tension.