| 摘要 |
A guidewire for use in guiding a catheter is provided with an expandable element at its distal region. The element may be expanded from a contracted configuration having a diameter corresponding to that of the guidewire and an expanded configuration larger than that diameter. A control element, such as a pull wire, extends through the guidewire from the proximal end of the guidewire and is associated with the expandable element to control expansion and contraction of the expandable element. The guidewire may be used in a number of modes. In one mode, the guidewire may be used to enhance the pushability of a catheter by locating the expandable element in the distal end of the lumen of the catheter and expanding the element at that location to lock the expandable element to the distal end of the catheter. Thereafter, the guidewire and catheter may be advanced in unison with the guidewire enhancing the pushability of the combination. In another mode of operation, the guidewire may be used with a single lumen balloon catheter in which the expandable element may be used both to enhance the pushability of the combination as well as to seal the distal end of the catheter to enable the balloon to be inflated and deflated through the catheter lumen. <IMAGE> |
