Method and apparatus useful for transcatheter aortic valve implantation
A guide catheter is described for introduction into a patient's vasculature, to provide a substantially continuous guide lumen within the vasculature to the ascending aorta, through which one or more other functional catheters may be introduced and removed during the procedure. The guide catheter includes an aligner at its distal region for aligning the position and/or inclination of the distal region of the guide catheter with respect to the ascending aorta. The aligner includes an embolic protection filter. The guide catheter is made of material collapsible/distensible in cross section to adopt a small shape when no catheter is present inside, and to distend to a large shape to accommodate passage of functional catheter therethrough. The cross-section shape collapses/distends by folding/unfolding of material without elastic stretching of the material.
1. A flexible guide catheter for use in a transvascular aortic valve replacement procedure, the guide catheter defining a substantially tubular delivery lumen through which one or more other functional catheters may be introduced, wherein the guide catheter comprises a flexible material that permits the lumen of the guide catheter to (i) collapse in cross-section to a compact form for introduction into vasculature constrained within a displaceable sheath, and (ii) distend in cross-section to a distended form to accommodate a maximum size of the one or more other functional catheters introduced therethrough,
wherein the guide catheter is self-biased to be in a stable intermediate form between the compact form and the distended form;
wherein the flexible material comprises a braid or mesh or woven structure of filaments,
wherein the braid or mesh or woven structure comprises open space permitting blood communication therethrough between an exterior and interior of the guide catheter, and
wherein the braid or mesh or woven structure permits distension to the distended form by rearrangement of the filaments without substantial elastic stretching of the filaments.
2. The guide catheter of claim 1 , wherein the guide catheter has a generally round cross-sectional shape in both the compact form and the distended form.
3. The guide catheter of claim 1 , further comprising a sleeve sealed to the flexible material of the guide catheter at or near a proximal end of the flexible material, and extending at least 20 mm distally along a length of the flexible material, the sleeve being elastically stretchable to accommodate expansion of the guide catheter when the at least one other functional catheter is introduced therethrough.
4. The guide catheter of claim 1 , further comprising, at least initially for introduction into the vasculature, a tapered or rounded tip at a distal region of the guide catheter.
5. The guide catheter of claim 1 , wherein the flexible material of the guide catheter is selected from: silicone, polyether block amide, metal, stainless steel, and nitinol.