Abstract: Ultrasonic transducer with a selectable beamwidth comprising a body of piezoelectric material in the form of an annulus having an outer diameter D and a thickness T. The body has proximal and distal generally planar parallel surfaces and a centrally disposed hole extending therethrough. The body has a cylindrical wall with a width W extending from the hole to the outer diameter. The transducer is capable of operating at low and high resonance frequencies with the low frequency resonance being determined by the diameter D and an aspect ratio of D/T and the high frequency resonance being determined by the thickness T and an aspect ratio of W/T.

Abstract: A guide wire assembly comprises a tubular body having a distal end and an proximal end. At least a portion of the body comprises a single continuous helical spring to which one or more tubular electrodes are secured. The electrodes are insulated from the spring by means of an insulator. The electrodes can take a variety of forms, including conductive ribbons, longitudinally split conductive tubes, tubular sections, etc. The guide wire assembly may further include a variety of sensors, such as velocity sensors or temperature sensors. In order to allow flowable material to be passed to the distal end of the guide wire, the guide wire can include a catheter tube passable over the tubular body of the guide wire.

Abstract: An intravascular guide wire comprising a flexible elongate member having proximal and distal extremities. A flexible elongate tubular member is coaxially disposed on the flexible elongate member. A coil assembly is secured to the distal extremity of the flexible elongate member.

Abstract: A guidewire having pressure sensing capabilities for measuring the pressure of liquid in a vessel comprising a flexible elongate member and having proximal and distal extremities and having an outside diameter of 0.018" or less. The distal extremity of said flexible elongate member is adapted to be disposed in the liquid in said vessel. A housing is carried by the flexible elongate member and has a diameter substantially the same as the diameter of the flexible elongate member. The housing has a space therein with a pressure sensor mounted in the space in the housing. The pressure sensor has a diaphragm that is sensitive to changes of pressure in the liquid in the vessel. The diaphragm is rectangular in shape and is bordered by a rim surrounding the well. A backing plate is formed of an insulating material bonded to the crystal and serves to reinforce the rim of the crystal of semiconductor material.

Abstract: Apparatus for the treatment of a thrombotic occlusion in a vessel of a patient comprising a flexible elongate tubular sheath having proximal and distal extremities. A relatively large lumen defined by a thin flexible wall extends from the proximal extremity to the distal extremity of the tubular sheath so that the distal extremity is open. An occlusion disruption device is slidably and rotatably disposed in the lumen in the tubular sheath and includes a flexible elongate torsionally rigid shaft having a length greater than the length of the tubular sheath and having proximal and distal extremities. The shaft has a guide wire lumen extending from the proximal extremity to the distal extremity. Disruption elements are secured to the distal extremity of the shaft which when rotated disrupt the thrombotic occlusion by causing it to break into pieces. Suction is applied to the lumen in the tubular sheath to aspirate pieces into the large lumen of the tubular sheath to remove them from the vessel of the patient.

Abstract: Pressure transducer circuitry accommodating pressure transducer variables for making pressure measurements in a living body. A microminiature piezoresistive pressure transducer has first and second variable resistive elements. The pressure transducer is characterized as having a pressure sensitivity ranging from 1.2 to 15 ohms per 1,000 ohms per 100 millimeters of mercury and a temperature characteristic greater than pressure sensitivity. Circuitry is coupled to the first and second variable resistive elements of the transducer including a known fixed resistive element. The known fixed resistive element is coupled to the first and second variable resistive elements for supplying a transducer excitation voltage through the known fixed resistive element to the first and second variable resistive elements. First and second amplifiers each having an input and an output are provided.

Abstract: Flexible elongate extension device for use with a flexible elongate member having proximal and distal extremities, comprising a flexible elongate extension member having proximal and distal extremities. A sleeve is secured to the distal extremity. The sleeve is sized to receive the proximal extremity of the flexible elongate member. A thermoplastic adhesive is disposed in the sleeve and has a lumen therein sized so it is adapted to receive the proximal extremity of the flexible elongate member.

Abstract: Ultrasonic transducer with a selectable beamwidth comprising a body of piezoelectric material in the form of an annulus having an outer diameter D and a thickness T. The body has proximal and distal generally planar parallel surfaces and a centrally disposed hole extending therethrough. The body has a cylindrical wall with a width W extending from the hole to the outer diameter. The transducer is capable of operating at low and high resonance frequencies with the low frequency resonance being determined by the diameter D and an aspect ratio of D/T and the high frequency resonance being determined by the thickness T and an aspect ratio of W/T.

Abstract: Piezoresistive pressure transducer circuitry accommodating transducer variables comprising microminiature pressure transducer having first and second variable resistive elements each having first and second ends, circuitry coupled to the first and second resistive elements of the transducer including third and fourth fixed resistive elements each having a first and second ends, means interconnecting the first ends of the first and second resistive elements, means interconnecting the second ends of the first and third resistive elements, means interconnecting the second ends of the second and fourth resistive elements, means interconnecting the first ends of the third and fourth resistive elements, means for supplying excitation to the first ends of the third and fourth resistive elements, first amplifier means having an input coupled to the means interconnecting the second ends of the first and third resistive elements, second amplifier means having an input coupled to the means interconnecting the second end

Abstract: A method of diagnosing and treating the human or animal body comprises feeding a flexible guide wire, dimensioned to be inserted into human coronary arteries, along a blood vessel in the human or animal body and epicardially mapping the electrocardiographic signals by means of electrodes secured to the guide wire. The method of diagnosing and treating the human or animal body may include the step of ablating selected body tissue by establishing a DC or radio frequency current through the body tissue between a pair of electrodes in which at least one of the electrodes is located on the guide wire. The method may also include passing flowable material to or from selected tissue by means of a catheter passed over the guide wire. The method may optionally include sensing the velocity of blood flow in the blood vessel by means of a velocity sensor mounted on the guide wire, or the temperature of selected body tissue by means of a temperature sensor mounted on the guide wire.

Abstract: Rotary connector for use with a flexible elongate member having electrical properties and having a proximal extremity with at least first and second conductive spaced-apart sleeves provided thereon. A housing is provided having a bore therein. First and second spaced-apart conductive disks are disposed in said bore. The disks are adapted to have the proximal extremity of the flexible elongate member extend therethrough and to have the conductive sleeves be in contact with the conductive disks while permitting rotation of the flexible elongate member, a push button clamping assembly is carried by the housing for retaining the proximal extremity of the flexible elongate member in the housing. Leads are connected to the conductive disks.

Abstract: Rotary connector for use with a flexible elongate member having electrical properties and having a proximal extremity with at least first and second conductive spaced-apart sleeves provided thereon. A housing is provided having a bore therein. First and second spaced-apart conductive disks are disposed in said bore. The disks are adapted to have the proximal extremity of the flexible elongate member extend therethrough and to have the conductive sleeves be in contact with the conductive disks while permitting rotation of the flexible elongate member, a push button clamping assembly is carried by the housing for retaining the proximal extremity of the flexible elongate member in the housing. Leads are connected to the conductive disks.

Abstract: Rotary connector for use with a small diameter flexible elongate member having electrical capabilities and having a proximal extremity with at least first and second spaced-apart conductive sleeves thereon. The rotary connector is comprised of a housing and at least first and second spaced-apart contact members mounted in the housing. The housing and the first and second contact members have passages therein through which the proximal extremity of the flexible elongate member can extend to place the first and second conductive sleeves in contact with the contact members. A clamping assembly means is carried by the housing for retaining the proximal extremity of the flexible elongate member in the housing while permitting rotation of the flexible elongate member with respect to the housing. The first and second contact members each have a base portion having proximal and distal sides.

Abstract: An apparatus for generating a velocity spectrogram is described. The apparatus includes a transducer which is positionable within a vessel. The transducer receives a time-varying Doppler signal which contains information related to fluid velocity values within the vessel. A Fourier transformation device processes the time-varying Doppler signal to generate a sequence of spectra. Each spectrum corresponds to a segment of the time-varying Doppler signal and defines a set of velocities and their corresponding spectral values. A device is used to identify the instantaneous spectral peak velocity within each spectra. The peak velocity corresponds to the highest velocity within a spectra which has a spectral value above a defined threshold value which is related to the background noise level. The sequence of spectral peak velocities is plotted on a visual interface device to form an instantaneous spectral peak velocity waveform.

Abstract: Vascular catheter for measuring flow characteristics of a liquid in a vessel having a wall and an axis extending longitudinally of the vessel parallel to the vessel wall comprising a flexible elongate tubular member adapted to be introduced into the vessel and having proximal and distal extremities. The flexible elongate member has a lumen extending therethrough. The flexible elongate member has at least one preformed bend thereon adjacent the distal extremity. A plurality of ultrasonic transducers are mounted on the flexible elongate member adjacent to the bend. Conductors are connected to the ultrasonic transducers and extend through the proximal extremity of the flexible elongate tubular member. The flexible elongate member has an opening therein in the distal extremity which is a communication with the lumen.

Abstract: A guide wire assembly comprising a guide wire with first and second conductors which extend along the length thereof. The guide wire also comprises a flexible cable having first and second conductors which extend along the length thereof. The connector assembly includes a male connector with a sleeve and a conductive core which is mounted in the sleeve. An insulator is mounted in the sleeve and insulates the conductive core from the sleeve. A conductive band is carried by the insulator and is spaced from the sleeve. The first and second conductors are disposed within the sleeve. The first connector is connected to the conductive core and the second conductor is connected to the conductive band. The connector assembly includes a female connector that has an inner conductive grip which has a cylindrical recess for receiving the conductive core and an outer conductive grip that has a cylindrical band which engages the portion extending forwardly of the inner conductive grip.

Abstract: A doppler guide wire having an inflatable balloon thereon which is inflatable with a balloon inflation medium. An elongate flexible member having proximal and distal extremities. An ultrasonic transducer is secured to the distal extremity of the elongate flexible member. An inflatable balloon mounted on the distal extremity of the elongate flexible member proximal of the ultrasonic transducer. A balloon inflation lumen opens into the interior of the balloon and extends along the length of the elongate flexible member. Conductors are connected to the ultrasonic transducer and extend along the length of the elongate flexible member.

Abstract: A guide wire assembly comprising a guide wire with first and second conductors which extend along the length thereof. The guide wire also comprises a flexible cable having first and second conductors which extend along the length thereof. A connector assembly is provided for interconnecting the flexible cable to said guide wire and interconnecting the conductors carried thereby. The connector assembly includes a male connector with a sleeve and a conductive core which is mounted in the sleeve. An insulator is mounted in the sleeve and insulates the conductive core from the sleeve. A conductive band is carried by the insulator and is spaced from the sleeve. The first and second conductors are disposed within the sleeve. The first connector is connected to the conductive core and the second conductor is connected to the conductive band.

Abstract: System for measuring a characteristic of flow of liquid in a vessel of a patient comprising a transducer positioned in a vessel in a patient for supplying ultrasonic energy. The transducer produces a substantially inform beam which encompasses the vessel. The transducer receives ultrasonic energy back scattered from the red blood cells and provides an electrical output signal. A first moment detector is provided which receives the electrical output from the transducer and provides a first moment signal. Normalization is provided to the output of the first moment detector to provide an electrical output representing a characteristic of the flow of the liquid in the vessel.

Abstract: System for measuring a characteristic of flow of liquid in a vessel of a patient comprising a transducer positioned in a vessel in a patient for supplying ultrasonic energy. The transducer produces a substantially uniform beam which encompasses the vessel. The transducer receives ultrasonic energy back scattered from the red blood cells and provides an electrical output signal. A first moment detector is provided which receives the electrical output from the transducer and provides a first moment signal. Normalization is provided to the output of the first moment detector to provide an electrical output representing a characteristic of the flow of the liquid in the vessel.