Flexible catheter guidewire

A flexible catheter guidewire comprising:

• a. an elongate flexible core comprising:
• a main section having a predetermined uniform diameter extending from a proximal end of the guidewire to a distal region of the guidewire;
• a tapered section extending distally from the main section and having a progressively reduced outer diameter;
• a flattened tip extending distally from the tapered section, the flattened tip having a substantially rectangular cross-section, the flattened tip comprising a first end and a second end, the first end of the flattened tip being attached to the tapered section, the thickness of the flattened tip decreasing from the first end of the flattened tip to the second end of the flattened tip;
• b. a coil spring attached to the core wire and disposed around the flattened tip, the coil spring being comprised of a radiopaque material:
• and
• c. a cylindrical, thin-walled hollow tube attached at one end to the core wire beginning at the tapered section and extending continuously up to the coil spring, where the other end of the thin-walled tube is attached to the core wire, the hollow tube having a substantially uniform inner diameter whereby a gap is formed between an inner surface of the hollow tube and an outer surface of the tapered section in order to provide a desired degree of flexibility and steerability, and the hollow tube having a substantially uniform outer diameter which corresponds to the outer diameter of the main section of the wire in order to provide a continuously and uniformly smooth outer surface along the length of the guidewire from the main section to the coil spring.

A flexible catheter guidewire comprising:

• a. an elongated flexible core wire comprising:
• a main section having a predetermined uniform diameter extending from a proximal end of the guidewire to a distal region of the guidewire;
• a tapered section extending distally from the main section and having a progressively reduced outer diameter;
• a flattened tip extending distally form the tapered section, the flattened tip having a substantially rectangular cross-section, the flattened tip comprising a first end and a second end the first end of the flattened tip being attached to the tapered section, the thickness of the flattened tip decreasing form the first end of the flattened tip to the second end of the flattened tip, the second end of the flattened tip having a thickness in the range of about 0.0008 inches to 0.0010 inches;
• b. a coil spring attached to the core wire and disposed around the flattened tip, the coil spring being comprised of a radiopaque material;
• and
• c. a cylindrical, thin-walled hollow tube attached at one end to the core wire beginning at the tapered section and extending continuously up to the coil spring, where the other end of the thin-walled tube is attached to the core wire, the hollow tube having a substantially uniform inner diameter whereby a gap is formed between an inner surface of the hollow tube and an outer surface of the tapered section in order to provide a desired degree of flexibility and steerability, and the hollow tube having a substantially uniform outer diameter which corresponds to the outer diameter of the main section of the core wire in order to provide a continuously and uniformly smooth outer surface along the length of the guidewire from the main section to the coil spring.