Abstract: The present invention relates to a device for determining a characteristic point in the cardiac cycle that comprises means for calculating the curve of the blood flow rate D(t) in the aorta from the curve of the arterial blood pressure signal P(t) and determining from the curve of the blood flow rate D(t) in each cardiac cycle the time at which an incisura point lies. The device can be used for activating an intra-aortal balloon pump (IABP).

Abstract: A device for inhibiting unintentional contact with the tip of a needle that has a wire guide disposed in a lumen thereof. A housing of the device has an interior cavity. A portion of the needle extends through the cavity and a tip of the needle is located outside of the housing during use of the needle. A pivoting member is located within the cavity and defines a distal opening and a proximal opening which are sized to allow the needle to pass through the openings. When the needle tip is within the cavity and the needle is withdrawn from the distal opening of the pivoting member, a spring or a compressible member cants the pivoting member into locking engagement with the needle to prevent further movement of the needle. Alternatively, a spring is in locking engagement with the needle to prevent its further movement.

Abstract: The present invention relates to a method and associated apparatus for improving the accuracy with which the speed of a fluid, such as a liquid, in particular blood flowing in a duct, such as a blood vessel, in particular the aorta, is measured by means of a signal emitted by a Doppler transducer (4). In characteristic manner, according to the method, the Doppler transducer is associated with a programmable memory (50) which contains at least one correction data item for correcting the Doppler signal transmitted by the transducer (4) to a transducer control and computer unit (8). Said computer unit (8) incorporates said signal correction data item in its computation (at 16) of each speed measurement on the basis of each signal emitted by the Doppler transducer, and it computes the speed value while taking account of said correction data item so as to provide a corrected measurement of the speed of said fluid, thereby improving its accuracy.

Abstract: The present invention relates to a device for determining a characteristic point in the cardiac cycle that comprises means for calculating the curve of the blood flow rate D(t) in the aorta from the curve of the arterial blood pressure signal P(t) and determining from the curve of the blood flow rate D(t) in each cardiac cycle the time at which an incisura point lies. The device can be used for activating an intra-aortal balloon pump (IABP).

Abstract: The invention relates to a device for protecting a cover. According to the invention, said cover is flexible and tubular in shape being closed at one end and open at its other end, and said cover is disposed at least in part inside a hollow tubular protective element referred to as a protective tube, which element is open at both ends. The device of the invention is particularly suited for use in the medical field, in particular for covering, preferably in sterile manner, a tool that is to be inserted in an animal or a human being, in particular in a natural passage such as the esophagus, the urethra, the rectum, or a blood vessel.

Abstract: The present invention relates to a device for determining a characteristic point in the cardiac cycle that comprises means for calculating the curve of the blood flow rate D(t) in the aorta from the curve of the arterial blood pressure signal P(t) and determining from the curve of the blood flow rate D(t) in each cardiac cycle the time at which an incisura point lies. The device can be used for activating an intra-aortal balloon pump (IABP).

Abstract: A guidewire advancement system for inserting catheter guidewires into blood vessels, and more particularly a guidewire dispensing system for the controlled sterile insertion of a coiled spring guidewire to avoid infection of the patient. The system provides for the transmission of an electrical signal by the guidewire to determine its location within the body.

Abstract: The present invention relates to a device for determining a characteristic point in the cardiac cycle that comprises means for calculating the curve of the blood flow rate D(t) in the aorta from the curve of the arterial blood pressure signal P(t) and determining from the curve of the blood flow rate D(t) in each cardiac cycle the time at which an [the] incisura point lies. The device can be used for activating an intra-aortal balloon pump (IABP).

Abstract: An optical system for positioning a pressure transducer relative to a patient to provide for accurate measurement of bodily fluids within the patient. A light source such as a laser is used to direct light onto a specified location on the human body to accurately identify the elevation of the transducer relative to the specified location to provide an absolute measurement of fluid pressure.

Abstract: A kink-resistant steerable catheter assembly suitable for microwave ablation includes a handle, a catheter and a steering control. The catheter has (a) a flexible, torque-transmitting and axially incompressible proximal or body portion terminating in a proximal end attached to the handle, and (b) a flexible and axially compressible distal or tip portion terminating in a distal end. A coaxial cable is disposed in and extends through a large aperture in the catheter proximal portion, and a coaxial cable extension is generally centrally disposed in, substantially fills, and snugly extends through a large lumen in the catheter distal portion to reduce kinking. The control is disposed in and actuatable from the handle, for placing tension on one of a pair of steering wires while relaxing tension on the other of the pair of steering wires, thereby to bend the distal end of the coaxial cable extension toward the tensed one of the steering wires.

Abstract: A helical antenna, which is matched to the desired microwave frequency of 915 MHz, comprises a helix having a linear length which is in the range of 74 to 112 mm or a non-zero integer multiple thereof, and which delivers microwave energy in an optimal heating pattern with little reflected power.

Abstract: A kink-resistant steerable catheter assembly suitable for microwave ablation includes a handle, a catheter and a steering control. The catheter has (a) a flexible, torque-transmitting and axially incompressible proximal or body portion terminating in a proximal end attached to the handle, and (b) a flexible and axially compressible distal or tip portion terminating in a distal end. A coaxial cable is disposed in and extends through a large aperture in the catheter proximal portion, and a coaxial cable extension is generally centrally disposed in, substantially fills, and snugly extends through a large lumen in the catheter distal portion to reduce kinking. The control is disposed in and actuatable from the handle, for placing tension on one of a pair of steering wires while relaxing tension on the other of the pair of steering wires, thereby to bend the distal end of the coaxial cable extension toward the tensed one of the steering wires.

Abstract: An electrode-carrying catheter has elongate, flexible tubing defining a proximal end, a distal end, and an electrically insulative outer tubular layer intermediate the ends, the tubing including a flexible core and a flexible non-conductive core-covering layer of plastic about the core. A plurality of electrically conductive electrodes is disposed on the outer tubular layer. In order to conduct electrical signals between the proximal end and each of the electrodes, a longitudinally-spaced plurality of flexible electrically conductive wires are helically wound around and at least partially into the core-covering layer. The wound wires define a removed section beneath a segment of each of the electrodes to enable electrical contact between a respective one of the wound wires and a respective one of the electrodes. Each electrode is in the form of an electrically conductive flexible flat ribbon for providing electrical communication with a respective one of the wound wires.

Abstract: A balloon pump for a circulatory assist device, the pump comprising a pumping chamber of variable volume in which a diaphragm assembly is displaceable in first and second pumping directions to inflate and deflate the balloon, the diaphragm assembly comprising a diaphragm sandwiched between a pusher plate and a retainer plate where the pusher plate and retainer plate are affixed to an elongated shaft having an external threaded portion disposed in a planetary roller nut, a rotor assembly is affixed to the roller nut and a stator assembly is disposed outwardly of the rotor assembly to impart bidirectional rotation to the roller nut to cause the shaft and diaphragm assembly to move in the first and second pumping directions, the pump communicating with a pump control unit and microprocessor for controlling pump operation.

Abstract: A non-rotational catheter clamp. The clamp comprises a snap-acting device which contains a rotatable inner and outer member. The inner member has an inner passageway for a catheter and an outer surface containing at least one protrusion. The outer member has an interior beveled sidewall. When the outer member is twisted or rotated in a first direction relative to the inner member, the protrusion on the inner member is compressed by the beveled sidewall, thereby compressing the inner member and the catheter. When the outer member is twisted in the opposite direction relative to the inner member, the protrusion disengages from the beveled sidewall and the catheter is decompressed. Use of the clamp in conjunction with a catheter contamination sleeve is disclosed.

Abstract: An improved intra-aortic balloon catheter of the present invention with a kink-resistant outer tube formed of a helically wound metal coil overlaid with a plastic covering which maintains the patency of the air passageway, and a central tub, forming a secondary lumen, formed of a strong resilient, flexible, kink-resistant material, such as a super elastic metal alloy.

Abstract: An introducer sheath for insertion into a patient's vascular system is provided having an irregular, undulating outer surface to interface with the irregular surface formed by the invasive procedure of inserting the sheath into a blood vessel. The sheath includes a helical coil member formed of continuous turns of spiral wound flat wire and a plastic sleeve surrounding the coil. Each turn of the coil is spaced apart from a next adjacent turn sufficiently to define therebetween an interstice wide enough to allow the plastic sleeve to be constricted into the interstices between the turns. A corresponding undulating outer surface is thereby formed to interface with a wall of blood vessel to minimize blood leakage therefrom. In the preferred embodiment, a lubricated inner plastic tube is proved, and a distal portion of the sheath surface has a smooth configuration.

Abstract: An electrode-carrying catheter has elongate, flexible tubing defining a proximal end, a distal end, and an electrically insulative outer tubular layer intermediate the ends, the tubing including a flexible electrically conductive core of wire and a flexible non-conductive core-covering layer of plastic about the core. At least one electrically conductive ring electrode is crimped on and flush with the outer tubular surface. In order to conduct electrical signals between the proximal end and each of the ring electrodes, a longitudinally-spaced plurality of flexible electrically conductive wires are helically wound around and at least partially into the core-covering layer. The wound wires define a removed section beneath a segment of each of the ring electrodes to enable electrical contact between a respective one of the wound wires and a respective one of the ring electrodes.

Abstract: A catheter is disclosed which is capable of cutting obstructive tissue from a vessel of a living body while shielding a portion of the wall of the vessel from being exposed to the cutting blade at the catheter's distal end. An essentially continuous outer surface at the catheter's distal end allows it to be readily advanced through an introducer sheath and through a tight stenosis in an artery. The shield at the catheter's distal end could subtend an arc from as little as 45 degrees to as large as 270 degrees depending on the extent of the vessel wall that is to be protected from being cut. A vacuum source at the catheter's proximal end can cause a suction to exist at a cutout at the catheter's distal end in order to pull obstructive tissue into the cutout as the cutting cylinder is pulled back in a retrograde direction, this suction being capable of enhancing the removal of the obstructive tissue.

Abstract: An electrode-carrying catheter has elongate, flexible tubing defining a proximal end, a distal end, and an electrically insulative outer tubular layer intermediate the ends, the tubing including a flexible electrically conductive core of wire and a flexible non-conductive core-covering layer of plastic about the core. At least one electrically conductive ring electrode is crimped on and flush with the outer tubular surface. In order to conduct electrical signals between the proximal end and each of the ring electrodes, a longitudinally-spaced plurality of flexible electrically conductive wires are helically wound around and at least partially into the core-covering layer.