Abstract: A method and device for transmyocardial revascularization using RF energy. A signal probe having a signal electrode is inserted into a myocardium. A return probe having a return electrode is placed on or within the myocardium. RF energy is supplied to the signal electrode, and forms a conductive path to the return electrode. At least one fissure within the myocardium is formed along the conductive path, allowing blood to perfuse within the fissure and revascularize the myocardium. A number of probe and electrode configurations are provided, including the use of multiple probes and electrodes, hollow probes to provide a coring effect, and pressurized fluid-supplying probes.

Abstract: An ultrasound transducer array probe for intraluminal ultrasound imaging is situated on a distal end of a catheter. The probe has a flex circuit that accepts terminations from a plurality of coaxial cables admitted through the catheter, and electrically conveys these signals to integrated circuits and an ultrasound array acoustic stack, preferably having seventy-two elements. The circuit has more than one layer of metal tracings to support complicated electrical interconnections. The acoustic stack preferably includes two quarter-wave matching layers and an acoustic backing layer composed of urethane, AIN.sub.3, tungsten trioxide, and micro-balloons. The flex circuit can be formed of two sections that are joined during manufacture.

Abstract: An ultrasound mixed signal multiplexer/pre-amplifier application specific integrated circuit (ASIC) for supplying voltages to a group of elements of an ultrasound array, receiving voltages from the same or another group of elements of the array, and amplifying the received voltages for transmission to external circuitry. The transmit groups and receive groups are shifted to provide accurate visual images with a minimal number of transmit and receive cycles.

Abstract: Obstructive material is removed from a stent by modified electrosurgical ablation. A modified electrosurgical device having at least one electrode is positioned within the stent, and current is supplied to the electrode. The electrode is prevented from physically contacting the stent, such as by being situated within a groove on the device. The stent may, but need not be, grounded to the current source. The device may be properly positioned within the stent by using ultrasound transducers, fiber optics, or other means. Additionally, the device may be positioned by including at least two electrodes, and measuring the impedance therebetween, as the impedance will be relatively low when both electrodes are within a conductive stent. Therapeutic fluid may be supplied through the catheter, and energy may be supplied to increase the activity of the fluid.

Abstract: An electrosurgical device for the resolution of an occlusive deposit within a lumen of the body, and a method of using such a device. The device has a distal end that is insertable within and along the lumen to a desired position with respect to the occlusive deposit. The distal end of the device includes a number of electrodes that are spaced about the device. The electrodes may be individually supplied with current, so that the location of resolution is controlled within the lumen.