Deflectable guide
Described herein are devices and methods for guide catheters having one or more regions of increased flexibility. A flexibility region comprises one tubular segment of the guide catheter with a non-linear seam between two non-concentric layers of material having different durometers. A non-linear seam, such as a zig-zag or sinusoidal configuration, permits controlled compression of lower durometer material between portions of higher durometer material.
1. A method for accessing a cardiac region of a patient, comprising:
advancing a guide catheter from a peripheral vascular site in a retrograde direction through an aorta into a left ventricle, the guide catheter comprising a tubular body comprising a proximal section and a distal section, the distal section comprising a deformation zone, a curved pre-deformation section proximal to the deformation zone and a curved post-deformation section distal to the deformation zone, wherein the deformation zone has a proximal end, a distal end, a longitudinal length and a longitudinal axis therebetween, a first constricting portion, a second constricting portion and a compressible portion in alternating configuration with the first and second constricting portions along the longitudinal axis, wherein the first and second constricting portions have a higher hardness and the compressible portion has a lower hardness and wherein the guide catheter further comprises a pull member coupled to a pull structure that is located in the post-deformation section;
steering the guide catheter into a subvalvular region adjacent mitral valve leaflets by pulling the pull member to bend the catheter such that the first and second constricting portions compress the compressible portion therebetween.
2. The method of claim 1 , wherein the proximal section has a pre-configured curve.
3. The method of claim 1 , wherein the pull structure comprises a ring-like structure.
4. The method of claim 3 , wherein a proximal end of the pull member is coupled to a rotating knob.
5. The method of claim 3 , wherein a proximal end of the pull member is coupled to a lever.
6. The method of claim 3 , wherein a proximal end of the pull member is coupled to a bias member.
7. The method of claim 1 , further comprising passing an instrument down a conduit of the guide catheter.
8. The method of claim 7 , wherein the instrument is a multi-window tunnel catheter.
9. The method of claim 7 , wherein the instrument is guidewire.
10. The method of claim 1 , wherein advancing the guide catheter comprises passing the guide catheter through an aortic valve to the left ventricle, and steering the guide catheter into the subvalvular region from the aortic valve comprises bending the deformation zone to prevent looping of the guide catheter below chordae tendinae of the left ventricle.
11. The method of claim 1 , wherein the deformation zone is at an angle with respect to the pre-deformation section.
12. The method of claim 11 , wherein the angle is from about 0 degrees to about 345 degrees.
13. The method of claim 1 , wherein the compressible portion is located between the first constricting portion and the second constricting portion.
14. The method of claim 1 , wherein the guide catheter further comprises a reinforcement structure surrounding the tubular body.
15. The method of claim 14 , wherein the reinforcement structure comprises a tubular braid.
16. The method of claim 1 , wherein the compressible portion of the deformation zone is a first compressible portion and wherein the deformation zone further comprises a second compressible portion and a third constricting portion, wherein the second compressible portion is in alternating configuration with the second and third constricting portion along the longitudinal axis of the deformation zone, wherein the second compressible portion has a lower hardness and the third constricting portion has a higher hardness, and wherein bending the catheter causes the second and third constricting portions to compress the second compressible portion.
17. A method for accessing a cardiac region of a patient, comprising:
advancing a guide catheter from a peripheral vascular site in a retrograde direction through an aorta into a left ventricle, the guide catheter comprising a tubular body comprising a proximal section and a distal section, the distal section comprising a deformation zone, a curved pre-deformation section proximal to the deformation zone and a curved post-deformation section distal to the deformation zone, wherein the deformation zone has a proximal end, a distal end, a longitudinal length and a longitudinal axis therebetween, a first constricting portion, a second constricting portion and a compressible portion in alternating configuration with the first and second constricting portions along the longitudinal axis, wherein the first and second constricting portions have a higher hardness and the compressible portion has a lower hardness and wherein the guide catheter further comprises a pull member coupled to a pull structure that is located in the post-deformation section;
passing the guide catheter through a cardiac valve orifice; and
steering the guide catheter into a subvalvular region adjacent the cardiac valve orifice by pulling the pull member to bend the catheter such that the first and second constricting portions compress the compressible portion therebetween.
18. The method of claim 17 , wherein the cardiac valve orifice is an aortic valve orifice.
19. The method of claim 17 , wherein the cardiac valve orifice is a mitral valve orifice.
20. The method of claim 17 , further comprising passing an instrument down a conduit of the guide catheter.
21. The method of claim 17 , wherein the instrument is a multi-window tunnel catheter.