Abstract: A balloon catheter of the present invention has an outer tube having a first lumen inside it. At the distal end of the outer tube is connected the proximal end of the balloon portion so that a balloon space is formed inside it, the distal end of the balloon portion is joined to a cylindrical front tip portion, and pressurized fluid is introduced into and released from the balloon space through the first lumen of the outer tube so as to make the balloon portion expand or contract. Inside the first lumen of the outer tube is arranged an inner tube having a second lumen freely slidable in the axial direction. The distal end of the inner tube projects out from the distal end of the outer tube and is detachably attached to the front tip portion. The balloon catheter of the present invention may have a guidewire detachably attached to the front tip portion rather than providing the inner tube.

Abstract: A double tube from which a balloon catheter having a high rigidity and a low fluid resistance can be easily produced by means of an extruder or the like, an apparatus for producing the double tube, a balloon catheter produced by using the double tube, and a process for producing the balloon catheter are provided. The double tube comprises an outer tube having a lumen extending from the distal end to the proximal end, and an inner tube which is provided within the outer tube and has a lumen extending from the distal end to the proximal end, wherein a longitudinal member in the strip form is provided as a connecting member which continuously connects the inner surface of the outer tube to the outer surface of the inner tube in the axial direction. A balloon catheter can be easily produced by using this double tube.

Abstract: A balloon catheter has an inner tube communicating with a blood introduction port provided at a tip of the balloon portion. The inner tube is affixed to the inner wall of the catheter tube by adhesion, melt-bonding, or integral formation. The balloon catheter has a small channel resistance in the channel where the pressurized fluid which expands and contracts the balloon portion flows, even when the catheter tube has been bent, and enables expansion and contraction of the balloon portion with a good response. Another balloon catheter has the balloon portions at a range of the end sides of the balloon portions smaller in sectional area compared with the balloon portions at the tip sides. The catheter is able to effectively prevent side effects which occur only rarely but which are serious when they do occur. The catheter impairs as little as possible the effect of assisting the heart action inherent to the IABP method without special measurement of the diameter of the patient's blood vessels.

Abstract: A catheter having a catheter tube. The catheter tube is comprised of a base tube comprised of a hard plastic with a linear elastic modulus of at least 100 kg/mm.sup.2 and a surface tube of an anti-thrombogenic material covering the outer circumference of the base tube. Further, The present invention provides a catheter set which is used when inserting the catheter and the like into the blood vessel of a patient. The catheter set comprises a retaining sheath whose distal end is inserted into a blood vessel and which has a hemostatic valve at its proximal end, a catheter having a catheter tube, which is inserted from the proximal end of the retaining sheath and thereby inserted into the blood vessel, and a holding ring for affixing said retaining sheath to the outer circumference of said catheter tube at any position in the axial direction.

Abstract: A balloon catheter used for intra-aortic balloon pumping (IABP). In the balloon catheter, an outer diameter of a catheter tube is not made constant in the axial direction. Rather, the outer diameter of the catheter tube from a hemostatic valve to a bifurcation, the portion which is positioned outside the patient's blood vessel, is made 3 to 30 percent larger than the outer diameter of the catheter tube from the balloon portion to the hemostatic valve, which is positioned inside the patient's blood vessel. The bifurcation has a first passage and a second passage. The first passage is communicating with a shuttle gas port and is disposed straight along the direction of the axial center of the catheter tube.

Abstract: A balloon catheter has an inner tube communicating with a blood introduction port provided at a tip of the balloon portion. The inner tube is affixed to the inner wall of the catheter tube by adhesion, melt-bonding, or integral formation. The balloon catheter has a small channel resistance in the channel where the pressurized fluid which expands and contracts the balloon portion flows, even when the catheter tube has been bent, and enables expansion and contraction of the balloon portion with a good response. Another balloon catheter has the balloon portions at a range of the end sides of the balloon portions smaller in sectional area compared with the balloon portions at the tip sides. The catheter is able to effectively prevent side effects which occur only rarely but which are serious when they do occur. The catheter impairs as little as possible the effect of assisting the heart action inherent to the IABP method without special measurement of the diameter of the patient's blood vessels.

Abstract: A balloon catheter used for intra-aortic balloon pumping (IABP). In the balloon catheter, an outer diameter of a catheter tube is not made constant in the axial direction. Rather, the outer diameter of the catheter tube from a hemostatic valve to a bifurcation, the portion which is positioned outside the patient's blood vessel, is made 3 to 30 percent larger than the outer diameter of the catheter tube from the balloon portion to the hemostatic valve, which is positioned inside the patient's blood vessel. The bifurcation has a first passage and a second passage. The first passage is communicating with a shuttle gas port and is disposed straight along the direction of the axial center of the catheter tube.

Abstract: A balloon catheter having a balloon part composed of a film which is formed from a polymer having a number average molecular weight of at least 50,000, and has an initial modulus at 100% of at least 95 kg/cm.sup.2 is provided. The balloon part is far excellent in preventive effect against its destruction is provided. The balloon catheter is suitable for use as a balloon catheter for intraaortic balloon pumping because the balloon part is prevented from being worn due to the rubbing of the balloon part against a calcified deposit on a blood vessel upon its practical operation.

Abstract: A dressing for a wound having a porous structure of continuous pores throughout the dressing made of minute filaments arranged in three dimensions and filmy links (viewed at a magnification of about 35 to 350) connecting the filaments. The porous structure has pores defined by the filmy interconnections. In other words, the wound dressing has a continuous open-celled structure in an expanded foam. The wound dressing can advantageously be made of a highly biocompatible material, such as poly-.alpha.-amino acid.

Abstract: A method of manufacturing a wound dressing having microscopic web-like interconnections and a porous structure of continuous pores throughout the wound dressing. In the first embodiment of the method, the dressing is produced by the steps of heating while simultaneously stirring a biocompatible material and solvent to form a homogenous solution; cooling while simultaneously stirring the homogenous solution to form a gel made of a dispersion of gel particles of the biocompatible material and freeze-drying the gel. In a second embodiment of the method, the wound dressing is produced by heating while simultaneously stirring a biocompatible material and the solvent to form a homogenous solution, cooling while simultaneously stirring the homogenous solution to form a gel made of a dispersion of gel particles of the biocompatible material; warming while simultaneously stirring the gel, allowing the warm gel to cool to form a soft gel and freeze-drying the soft gel.