Abstract: The present invention relates to a vascular filter (1) which can beplaced in a blood vessel, and which comprises at least one passage with a circumference suitable for the purpose of intercepting thrombus, wherein the filter (1) comprises a longitudinal body member (6) with, in a position of use, a circumference corresponding to the internal diameter of the blood vessel transverse to the longitudinal direction thereof. The invention also relates to a method for manufacturing vascular filter (1).

Abstract: This invention related to a catheter comprising a tube-like basic body with a proximal and a distal end and a high-frequency generator associated with the catheter used for the purpose of generating high-frequency mechanical vibrations at the distal end of the catheter. The catheter comprises a lumen to be filled with liquid which is connected at the proximal end to an area inside of which a high-frequency movable member of the high-frequency generator is located and wherein at the distal end of the catheter a guide have been arranged for deflecting high frequency longitudinal waves traveling through the liquid inside the lumen in a lateral direction.

Abstract: A medical device, such as a medical catheter, having an imaging marker integral with the wall of the catheter but of a configuration such that the outer dimensions of the imaging marker remain substantially the same when the catheter is viewed along an x-axis, a y-axis and a z-axis to thereby present an image of substantially the same brightness regardless of the viewing angle.

Abstract: A drainage catheter comprises a tubular basic catheter body defining separate catheter lumens respectively comprising a pressure channel and a discharge channel. Connectors are provided at the proximal end of the catheter for respectively connecting the pressure channel to a source of liquid under pressure and the discharge channel to a discharge receptacle. An inlet opening is positioned in the side of the catheter adjacent the distal end thereof. The discharge channel communicates with the inlet opening, while the pressure channel extends from the proximal and distally forward of the inlet opening and then curves rearwardly to join the discharge channel at the inlet opening.

Abstract: An intravascular catheter having controllable stiffness or flexibility, and adapted for use with various contrast media. The stiffness of the catheter may be increased during the use of the catheter by applying a fluid under pressure at the proximal end of the catheter to thereby fill a cavity within the body of the catheter to thereby cause the region of the catheter defined by the cavity to become less flexible. When the fluid pressure is decreased, this region of the catheter becomes more flexible. The fluids to be applied inside the cavities may be a variety of types of contrast media, used with imaging techniques such as either MRI or X-ray fluoroscopy.

Abstract: A medical catheter comprising an outer tubular member and an inner tubular member slidably disposed within a lumen of the outer tubular member. The inner tubular member includes ridges which project outwardly from the outside surface thereof and which extend longitudinally along substantially the entire length of the inner tubular member to thereby provide a catheter which is flexible and highly resistant to kinking. The catheter further includes connectors for coupling the catheter to a source of fluid and for providing a passageway for a guidewire.

Abstract: The invention relates to a catheter comprising a tube-like basic body with a proximal and a distal end, marking means made of a material opaque to X-radiation arranged close to the distal end. The marking means may be formed by at least one tube-like marker sleeve made of a plastic material opaque to X-radiation arranged around the basic body. At the distal end a balloon member may have been arranged and the marker sleeve may substantially extend over the effective length of the balloon member.

Abstract: An intraventricular multielectrode cardiac mapping probe having an electrode array assembly which is initially stored within the distal lumen of a delivery catheter and after placement of the tip of the catheter at a target location within the heart the electrode array may be moved out of its retracted position to expand into a generally planar configuration to position electrodes for mapping of the heart chamber.

Abstract: A method of making a catheter is provided. The catheter has an atraumatic portion at the distal end of a catheter having the stiffness and torque resistance required of a catheter such as that suitable for angiographic uses, typically in French sizes on the order of about 2 to about 8. The atraumatic tip portion has a generally co-axially layered structure. An inner layer is made of soft atraumatic polymer, and an outer layer is made of a polymer to impart needed stiffness and torque properties to the catheter. In the preferred embodiment, a portion of the distal tip material of the harder outer layer is removed, thereby exposing the inner, atraumatic material for initial engagement with internal body passageways.

Abstract: A spinwelding procedure is provided for joining thermoplastic tubular members together at their respective axial ends. Axial end portions of very thin tubes are circumferentially supported both internally and externally, and one of the tubes is then rotated with respect to the other until adequate friction develops to melt the thermoplastic materials, after which they cool to heat bond together.

Abstract: A substrate for medical devices and a process for making the substrate is provided, the substrate having on at least part of its surface a blood-compatible surface produced by coupling a physiologically active substance to the surface. The physiologically active substance is one having an inhibitory effect on the formation of blood clots and/or is capable of breaking down blood clots formed. The physiologically active substance is bonded to a polyacid, and the polyacid is attached to the surface by a covalent bond.

Abstract: An electrochemical reference electrode having improved potential stability is provided, such reference electrode being suitable for use as a second-order or half-cell component within a system for measuring the ion concentration of body liquids. The reference electrode includes an electrode of the metal/metal cation type in association with an electrolyte that includes a soluble salt of the metal cation of the electrode, which soluble salt is present within the electrolyte in an amount sufficient to have metal cation present in the electrolyte at its saturation concentration.

Abstract: Conjugates are provided which are covalently bonded conjugates of an anticoagulant and protein that are prepared in the presence of a coupling agent that forms amide linkages between the anticoagulant and the protein. Such amide linking coupling agents exclude highly toxic coupling agents such as CNBr. These conjugates are useful for enhancing the blood compatibility of certain surfaces of a prosthetic device, a surgical apparatus, or an extra-corporeal medical device.

Abstract: The apparatus (14) is constructed and arranged to measure ions in a liquid (30) and comprises a measuring circuit (10) including an ISFET (16), a reference electrode (32), an amplifier (22) and a protection system (12)/guard circuit (40) connected to the measuring circuit (10). The protection system 12/guard circuit 40 comprises at least one electrode (46 or 47) connected via a low-impedance contact (or ring 62/46 or ring electrode 42) to the liquid (30) and coupled to the ISFET (16) by a protective element (64; 65, 66; or 68 and/or 50; 51, 52; 54; 56; or 58) having a low-impedance for high voltages and a high resistance to low voltages.In one preferred embodiment, the ISFET (16) is provided on a chip (90) and has an electrode (46/62) in as closely spaced relationship as possible to the gate region (34) of the ISFET (16).

Abstract: A new reference electrode assembly is provided that includes a hydrogen ion specific electrode which is encapsulated in a polymer matrix. The bulk of the polymer matrix has an open cell structure within which a liquid is contained as the electrode potential producing agent, while its surface is such that it forms a barrier preventing a free and open connection to the environment of the reference electrode. The reference electrode assembly is especially suitable for in vivo measurements, and it may be designed so that it is substantially insensitive to pH variations of the solution being measured by the instrument of which the reference electrode assembly is a part.

Abstract: An in vivo electrochemical monitoring device is formed by a catheter-like member which terminates in a closed end having a wall with a fixed opening to admit fluid to be tested, such as blood in an artery. An electrochemical sensor, such as an ISFET device for monitoring the concentration of a particular ion in blood, is mounted inside the tube at a fixed location below the opening preferably a larger sensing chamber. An infusion channel in the tube is arranged to flood the sensor with a fluid of known chemical properties so that the sensor output can be calibrated. Under pressure the calibration fluid expels the test fluid out of the tube or chamber via the fixed opening. A method of constructing a suitable chamber on an ISFET wafer is also disclosed.

Abstract: Conjugates are provided which are covalently bonded conjugates of an anticoagulant and protein that are prepared in the presence of a coupling agent that forms amide linkages between the anticoagulant and the protein. Such amide linking coupling agents exclude highly toxic coupling agents such as CNBr. These conjugates are useful for enhancing the blood compatibility of certain surfaces of a prosthetic device, a surgical apparatus, or an extra-corporeal medical device.

Abstract: An in vivo electrochemical monitoring device is formed by a catheter-like member which terminates in a closed end having a wall with a fixed opening to admit fluid to be tested, such as blood in an artery. An electrochemical sensor, such as an ISFET device for monitoring the concentration of a particular ion in blood, is mounted inside the tube at a fixed location below the opening preferably a larger sensing chamber. an infusion channel in the tube is arranged to flood the sensor with a fluid of known chemical properties so that the sensor output can be calibrated. Under pressure the calibration fluid expels the test fluid out of the tube or chamber via the fixed opening. A method of constructing a suitable chamber on an ISFET wafer is also disclosed.