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.

Circumferential ablation device assembly

An ultrasound treatment system comprises an ultrasonic transducer, a handpiece, a probe, a sheath, a clamping member, an operation unit, an operating member, a suction base, and a perfusion base. The ultrasonic transducer generates ultrasonic vibrations. The handpiece has the ultrasonic transducer incorporated therein. The probe is connected to the ultrasonic transducer for transmitting ultrasonic vibrations to a distal member realizing a stationary portion that is a treatment portion for treating a living tissue. The sheath serves as a protecting member for shielding the probe. The clamping member is opposed to the distal member at the distal end of the sheath for clamping a living tissue in cooperation with the distal member. The operation unit is manipulated for clamping a living tissue with the clamping member and distal member or freeing the living tissue therefrom.

Ultrasound treatment system

Devices, systems and methods are disclosed for the ablation of tissue. Embodiments include an ablation catheter that has an array of ablation elements attached to a deployable carrier assembly. The carrier assembly can be constrained within the lumen of a catheter, and deployed to take on an expanded condition. The carrier assembly includes multiple electrodes that are configured to ablate tissue at low power. Systems include an interface unit with a visual display that provides a visual representation of the geometry of the ablation elements and/or provides selection means for selecting an icon provided on the display.

User interface for tissue ablation system

This invention is a method for treating a patient diagnosed with atrial arrhythmia by forming a circumferential conduction block along a circumferential path of tissue in a pulmonary vein wall that circumscribes the pulmonary vein lumen and transects the electrical conductivity of the pulmonary vein such that conduction is blocked along the longitudinal axis of the vein wall and into the left atrial wall. The method is performed to treat a patient with a focal arrythmogenic origin along the pulmonary vein wall by either ablating the focal origin or by isolating the focal origin from the atrial wall with the circumferential conduction block. The circumferential conduction block is also formed in a pulmonary vein in order to bridge the adjacent ends of two linear lesions, wherein each linear lesion is formed to extend between the pulmonary vein and another adjacent pulmonary vein in a less-invasive “maze”-type procedure. A circumferential ablation element in a circumferential ablation device assembly is used in a percutaneous translumenal catheter technique in order to form the circumferential conduction block in the pulmonary vein wall.

Device and method for forming a circumferential conduction block in a pulmonary vein

A tissue ablation catheter for forming a lesion along a substantially circumferential region of tissue is described. The catheter includes one or more sensors for monitoring the temperature of the tissue being ablated. The temperature sensors are mounted on the interior or exterior of an expandable member that is affixed to a shaft of the catheter.

Medical device with sensor cooperating with expandable member

A catheter includes a piezoelectric transducer mounted to the distal end of a catheter. In one embodiment, the piezoelectric transducer has the shape of a cylinder and in another embodiment, a convex shape with a mounting flange. In the cylindrical shape, a plurality of surface mounted temperature sensors are disposed within the piezoelectric transducer. The sensors are electrically insulated and a sealing technique prevents the leakage of body fluids from penetrating the interior of the catheter through the sensor bores. The cylindrical transducer is supported on mounting members so that it is accurately mounted and sealed while at the same time, the material used does not significantly dampen the transducer. The convex shape includes a temperature sensor at its tip.

Catheter having ultrasonic device

A steerable catheter comprising a resilient body member, a manipulation handle attached to the proximal end of the body member, a control wire extending from the handle to the distal end of the catheter for deflection control, and a pulley mechanism for controlling the movement of the control wire. Longitudinal movement of a slide element in the handle causes movement of the control wire and control over the deflection of the distal end of the catheter. The pulley mechanism is connected between the slide element and the control wire to provide greater mechanical advantage to effect deflection of the body member while enhancing deflection control resolution. A stiffening member is also disposed in the catheter body member and its position is controlled by the rotational motion of the slide element. The position of the pulley mechanism is not affected by rotational motion of the slide element.

Tracy D. Maahs

Papers

Catheter having ultrasonic device

Catheter control system having a pulley