| 摘要 |
A bidirectional steerable catheter comprises a catheter body, a tip section and a control handle. The catheter body has a tubular wall, proximal and distal ends, and at least one lumen extending therethrough. The tip section comprises flexible tubing having proximal and distal ends and at least one lumen extending therethrough. The proximal end of the tip section is fixedly attached to the distal end of the catheter body. The control handle is mounted at its distal end to the proximal end of the catheter body. The control handle comprises a housing having proximal and distal ends. A distal piston is mounted in the distal end of the housing and fixedly attached to the proximal end of the catheter body. The distal piston is slidably movable relative to the housing. First and second proximal pistons are mounted in the housing proximal to the distal piston. Each of the proximal pistons is slidably movable relative between proximal and distal positions to the housing. The control handle further comprises a movable member capable of selectively and releasably engaging one of the proximal pistons to prevent slidable movement of that engaged proximal piston relative to the housing while allowing slidable movement of the other non-engaged proximal piston relative to the housing so that proximal movement of the housing relative to the distal piston and catheter body results in proximal movement of the engaged proximal piston relative to the distal piston and catheter body. The catheter further comprises a pair of puller wires having proximal and distal ends. Each puller wire extends from the control handle, through a lumen in the catheter body and into an off axis lumen in the tip section. The distal end of each puller wire is fixedly attached to the tip section, and the proximal end of each puller wire is anchored to a separate associated proximal piston in the control handle. In practice, proximal movement of the selectively engaged proximal piston and its associated puller wire relative to the catheter body results in deflection of the tip section in the direction of the off axis lumen into which that associated puller wire extends. |
