| 摘要 |
<p>An introducer system for a lead, catheter, probe or the like, employing a dilator 42 and introducer sheath 40 assembly for dilating a body vessel in preparation for introducing the lead, etc., through the lumen 58 of the introducer sheath that is easily advanced into the body vessel while minimizing injury to the vessel wall. The elongated tubular dilator 42 is formed with a tapered distal end portion extending proximally of a reduced diameter distal tip end to a relatively uniform major diameter. The introducer sheath major lumen diameter is dimensioned to fit snugly over the major diameter and to have a reduced distal end opening diameter from the major lumen diameter. An annular recess 70 is formed in the dilator adjacent to the distal end portion for receiving the reduced distal end opening diameter, such that when so assembled, a smooth transition of the dilator and sheath outer surfaces are presented proximal to the tapered distal end portion. The introducer sheath wall thickness may also be tapered in a distal introducer sheath portion. The annular recess and/or the sheath distal end opening are shaped to provide a cam surface to allow retraction of the distal end portion of the dilator past the reduced diameter sheath distal end opening. The sheath preferably is constructed to readily tear in a longitudinal direction and thus permits the system to be removed from the venous system without having to withdraw the sheath over an end of the lead, etc. <IMAGE></p> |
