Methods and apparatus for performing valvuloplasty
The present invention relates to apparatus and methods for performing valvuloplasty. In some embodiments, the apparatus includes an expandable braid valvuloplasty device. In some embodiments, the methods and apparatus may be used as an adjunct to percutaneous heart valve replacement. In some embodiments, the apparatus and methods may provide a medical practitioner with feedback, monitoring or measurement information, e.g., information relevant to percutaneous transcatheter heart valve replacement.
1. A control assembly for deploying and retrieving a valvuloplasty apparatus comprising:
an outer shaft having a distal end, a proximal end, and an outer shaft lumen extending therebetween;
an inner shaft having a distal end and a proximal end, the inner shaft being sized and adapted to be coaxially slideable from an initial position of the inner shaft within the outer shaft lumen;
a handle connected to the proximal end of the outer shaft;
a trigger pivotably connected to the handle and operably connected to the proximal end of the inner shaft via an intervening spring having an initial degree of elongation, a ratchet element, and a rotationally constrained element,
wherein as the trigger is pulled toward the handle the rotationally constrained element engages the ratchet element and the inner shaft is retracted proximally relative to the outer shaft;
a tubular braid having a proximal end and a distal end,
wherein the proximal end of the tubular braid is connected to the distal end of the outer shaft and the distal end of the tubular braid is connected to the distal end of the inner shaft,
wherein the tubular braid has a first elongated configuration having a first diameter and a second foreshortened configuration having a second diameter greater than the first diameter,
wherein when the trigger is pulled toward the handle, the tubular braid moves from the first elongated configuration toward the second foreshortened configuration;
a displacement indicator attached to the proximal end of the inner shaft and located adjacent to a displacement display attached to the handle; and
a force indicator attached to the proximal end of the inner shaft and displaced from the displacement indicator,
wherein the force indicator is located adjacent to a force display moveable with the ratchet element relative to the handle,
wherein a position of the force indicator relative to the force display indicates an amount of radial expansion force applied to the tubular braid.
2. The control assembly of claim 1 , wherein a position of the displacement indicator relative to the displacement display indicates a degree of proximal displacement of the inner shaft from the initial position of the inner shaft relative to the outer shaft.
3. The control assembly of claim 2 , wherein the degree of proximal displacement of the inner shaft from the initial position relative to the outer shaft indicates an amount of foreshortening of the tubular braid.
4. The control assembly of claim 2 , wherein the displacement display is calibrated such that the position of the displacement indicator relative to the displacement display indicates a diameter of the tubular braid.
5. The control assembly of claim 1 , wherein the position of the force indicator relative to the force display indicates a degree of elongation of the intervening spring.
6. The control assembly of claim 1 , wherein the force display is calibrated in load units.
7. The control assembly of claim 1 , wherein the rotationally constrained element is rotationally constrained in a direction toward the intervening spring.
8. The control assembly of claim 1 , wherein the force indicator is displaced longitudinally from the displacement indicator.