Controlled steering functionality for implant-delivery tool
A catheter ( 14 ), advanced toward an anatomical site, has a proximal end and a steerable distal end. An anchor ( 32, 2332 ) is advanced through the catheter. An anchor driver ( 36 ) drives the anchor out of the catheter's distal end ( 104 ), anchoring the anchor at the site. A first constraining member ( 1602, 1652 ) engages tissue, and inhibits, after the anchor has been driven out of the catheter and before the anchoring, movement of at least the anchor driver's distal end, on a first axis between the anchor driver's distal end and a site at which the first constraining member engages the tissue. A second constraining member ( 26 ) inhibits, after the anchor has been driven out of the catheter and before the anchoring, movement of at least the anchor driver's distal end, on a second axis. Other embodiments are also described.
1. Apparatus, comprising:
a catheter, transluminally advanceable to a valve of a heart of a subject;
an implant:
configured to be advanced distally through the catheter such that a distal end of the implant is placeable against tissue of the valve while a proximal end of the implant is disposed within the catheter, and
having a longitudinal axis between the distal end of the implant and the proximal end of the implant, and a lateral surface that circumscribes the longitudinal axis to define a lumen along the longitudinal axis;
a guidewire:
configured to be advanced distally through the catheter,
coupled to the implant such that at least a distal portion of the guidewire extends distally from a hole in the lateral surface of the implant, the distal portion of the guidewire being configured to be advanced between leaflets of the valve,
the apparatus being configured to mechanically bias placement of the distal end of the implant against the tissue of the valve at least in part dependently on a distance along the longitudinal axis between the distal end of the implant and the hole;
a tissue anchor; and
an anchor driver, configured such that the tissue anchor can be advanced through the catheter, into the lumen, and along the lumen to the distal end of the implant, and subsequently anchor the distal end of the implant to the tissue of the valve, by driving the tissue anchor through the lateral surface proximate the distal end of the implant and into the tissue of the valve.
2. The apparatus according to claim 1 , wherein the apparatus is configured to bias the placement of the distal end of the implant against the tissue at least in part dependently on a stiffness of the guidewire.
3. The apparatus according to claim 1 , wherein the guidewire is configured to engage a commissure of the valve, and the apparatus is configured, when the guidewire engages the commissure, to inhibit movement, on a plane of the valve, of the distal end of the implant outside of an arc centered on the commissure.
4. The apparatus according to claim 1 , wherein the guidewire is coupled to the implant such that the guidewire extends proximally from the hole and out of a body of the subject.
5. The apparatus according to claim 4 , wherein the guidewire extends proximally from the hole, exits from a point in the lateral surface of the implant, and extends proximally through the catheter along the outside of the implant.
6. The apparatus according to claim 1 , wherein the guidewire is retractable through the hole and decouplable from the implant.
7. A method for using the apparatus of claim 1 , the method comprising:
transluminally advancing a distal end of the catheter toward an anatomical site of the subject;
advancing the implant through at least part of the catheter while the distal portion of the guidewire extends out of the lateral surface of the implant;
implanting the implant at the anatomical site; and
removing the guidewire from the subject.