Flexible sheath with varying durometer

A sheath and catheter assembly, comprising:

• a sheath having a proximal end and a distal end, said sheath comprising:
• an inner tube having a passageway extending longitudinally therethrough, said passageway having a substantially uniform diameter;
• a coil comprising a plurality of turns positioned longitudinally around said inner tube, said turns having a predetermined spacing therebetween;
• and an outer tube positioned longitudinally around said coil and connected to said inner tube through the spaces between said turns, said outer tube comprising a plurality of tube segments, said segments aligned in order of decreasing durometer toward said distal end;
• and
• a catheter having a proximal end and a distal end, said catheter sized for insertion into said inner tube passageway, and further sized such that at least a portion of said catheter distal end extends beyond the distal end of said sheath when said catheter is inserted into said passageway;
• said catheter having an outer diameter that is 0.0005 to 0.004 inch (0.013 to 0.10 mm) less than a diameter of said passageway.

A method for inserting an introducer sheath into a patient's vasculature, comprising:

• inserting a wire guide into the patient's vasculature;
• threading a dilator over said wire guide into said vasculature, said dilator being positioned within a passageway of an introducer sheath, said sheath comprising an inner tube having said passageway extending longitudinally therethrough, a coil comprising a plurality of turns positioned longitudinally around said inner tube, and an outer tube positioned longitudinally around said coil and said inner tube connected to inner tube through the spaces between said turns, said outer tube comprising a plurality of tube segments, said segments aligned in order of decreasing durometer from said proximal end to said distal end;
• withdrawing the dilator while leaving the sheath in said vasculature;
• inserting a catheter into said vasculature through said sheath passageway, said catheter including a distal end shaped to facilitate entry into a remote area of said vasculature;
• and
• accessing said remote area via said shaped distal end.