| 摘要 |
A catheter adapted to deliver therapeutic or diagnostic agents to a target tissue of a human body is disclosed. A catheter in accordance with the present invention comprises a first elongate shaft having a proximal end, a distal end, and a lumen extending therethrough, a second elongate shaft disposed within the lumen of the first elongate shaft, the first elongate shaft including a first helical member comprising a plurality of turns, the second elongate shaft including a second helical member comprising a plurality of turns. Wherein, at least one turn of the second helical member is disposed proximate at least one turn of the first helical member. |
