An improved balloon catheter is disclosed having both the flexibility of a coaxial construction and the advantages of dual lumen construction as well. The proximal section is of relatively rigid dual lumen construction, wherein an inflation lumen and a guidewire lumen extend longitudinally through the proximal section in a generally parallel and side-by-side relationship. A distal section of the balloon catheter is coupled to the distal end of the proximal section and is of a coaxial construction. Near the transition between the two sections, an inner coaxial member defining the distal guidewire lumen is offset from the center of the otherwise coaxial distal section so that the inner coaxial member is substantially aligned with the distal end of the proximal guidewire lumen. The distal and proximal portions of the guidewire lumen are aligned and heat sealed together at the transition between the dual lumen constructed proximal section and the coaxially constructed distal section of the balloon catheter, to provide a continuous guidewire lumen extending through both sections all the way to a balloon mounted near the distal tip of the distal section. In the dual lumen constructed proximal section, the inflation lumen has a generally crescent-shaped cross section. At the transition region, the proximal inflation lumen narrows somewhat to a circular cross section. The proximal inflation lumen communicates with a substantially annular distal inflation lumen defined between the inner wall of an outer coaxial member and the outer wall of an inner coaxial member in the coaxially constructed distal section.
A laser balloon catheter device includes a housing containing a guidewire and an inelastic balloon. The balloon is surrounded by a clear silicone sleeve. A series of polyester electrically conductive flexible film strips are embedded inside the sleeve and adjacent the balloon. Each strip contains several vertical cavity surface-emitting lasers, each operating at 760-780 nanometer wavelengths and 1-10 milliwatts of power. During a balloon angioplasty procedure, the device is inserted into an affected artery across a region of stenosis. The balloon is inflated using inflation fluid provided from an external source. The inflated balloon expands the artery to eliminate the stenosis. Power is simultaneously applied to the lasers for a period of 5-10 minutes to encourage healing of the artery and reduce the occurrence of restenosis.
The catheter (5) with a flexible tip (20) includes a manifold (25) at the proximal end, a flexible catheter body (40) having a proximal end and a distal end, a balloon (15) at the distal end and a distal flexible tip (20). The catheter is designed for operation as an "over the wire" catheter and would be compatible with a flexible guidewire, such as guidewire (30). The flexible tip invention also would be compatible with "rapid exchange" or "single operator exchange" catheters. Flexible tip (20) extends distally from balloon (15) and guidewire shaft (55). In the preferred embodiment flexible tip (20) is formed from distal material of balloon (15). The length of the flexible tip (20) will vary depending on the path that catheter (5) must travel through the artery to get to its desired location. The length of the tip will balance the pushability desired versus the flexibility desired. A longer flexible tip (20) on catheter (5) would allow enough flexibility at the tip for catheter (5) to get at hard to reach lesions through a tortuous path. A shorter flexible tip (20) on catheter (5) would make the tip stiffer and allow higher pushability through blocked arteries. By varying the flexible tip (20), the catheter 5 may be designed for many different conditions.
The present invention relates to a rapid-exchange dilatation catheter of the type comprising a flexible tubular body having a distal part, an intermediate part and a proximal part. According to the invention, the body comprises a core having a high modulus of elasticity, which core is permanently joined at one end to the proximal part and embedded at its other end in a wall defining an inner duct for a guide-wire to pass through. The invention finds a particular application in the treatment of stenoses of blood vessels.
A balloon dilatation catheter defines a side aperture defined in the catheter shaft between the ends of the catheter and communicating between the guidewire lumen and the catheter exterior. A removable support mandrin may occupy a proximal lumen of the catheter. The mandrin may define a distal tip portion which is positioned preferably closely proximal to the aperture. The distal tip portion may have a reduced diameter relative to the average diameter of portions of the mandrin which are proximal to the tip portion, for providing mandrin tip flexibility. Also, a catheter-stiffening bridge member may be positioned within and permanently secured to the catheter adjacent to the aperture portion, to reduce catheter kinking adjacent thereto.
Catheter assembly in which an imaging transducer is positioned proximally of a treatment device at the distal end of a catheter. Unrestricted flow between a fluid lumen in the catheter and the treatment device is provided by an annular passageway formed between the walls of a marker tube which extends through the transducer and a guide wire tube which passes through the marker tube, and by a plenum chamber which is formed between the distal end of the catheter and the proximal end of the marker tube in communication with the fluid lumen and the flow passageway. The catheter, the treatment device, and the transducer are all constructed as individual modular units which can be assembled together as desired to form the assembly.
