Multiple segment catheter and method of fabrication

Abstract

Methods of fabricating medical vascular catheters adapted to be inserted into a blood vessel from an incision through the skin of a patient for introducing other devices or fluids for diagnostic or therapeutic purposes and particularly methods for fabricating such catheters with catheter bodies having catheter sections of differing flexibility are disclosed. Such catheter bodies having a proximal catheter body end and a distal catheter body end and formed of a proximal section and at least one distal section that have differing flexibilities are formed in a process comprising the steps of: (1) forming a continuous tubular inner jacket preferably of an inner liner and a reinforcement layer; (2) forming initial layer segments having an initial layer thickness along the length of the inner jacket from a material of first durometer hardness, whereby each initial layer segment is separated by a separation distance: (3) forming a final layer of a material of second durometer hardness with a second layer thickness over the tubular inner jacket along the separation distances and over and/or against the proximal and distal initial layer ends of the initial layer segments to form a continuous catheter body tubing; (4) severing the continuous catheter body tubing into catheter body lengths including a proximal catheter section formed of the material of second hardness and a distal catheter section of the material of first hardness; and (5) completing the catheter fabrication at the proximal catheter body end and the distal catheter body end. Centerless grinding of the catheter body or body tubing, formation of Intermediate catheter body sections, distal soft tips, and discontinuities in the reinforcement layer formed prior to step (2) are also disclosed.