| 摘要 |
A catheter enabling a reduced puncture hole size into the skin and blood vessel is disclosed. In one embodiment, the catheter has an elongate body having an expandable sheath extending at least a portion of its length. A pressure constraining sheath is positioned to surround the expandable sheath, at a selected region to prevent expansion of the inner sheath at the region of the constraining sheath. In one preferred use, the constraining sheath is positioned at the puncture hole. During use, the catheter increases in cross-section by an expandable sheath expanding from a first diameter to a second diameter. However, the outer sheath does not expand, maintaining a small diameter at the puncture site. |
