Rapid exchange stent delivery catheter
A rapid exchange balloon catheter has a short rapid exchange length for faster catheter exchanges the balloon catheter includes a balloon structure having a balloon leg connected to a catheter shaft. Marker bands may be provided in the balloon leg for facilitating measurement of a dimension of physiological features. A stiffening wire extending longitudinally at least partially into the balloon leg may be provided to supplement and control the flexibility characteristics of the balloon leg.
1 . A rapid exchange stent delivery catheter comprising:
a catheter shaft defining a primary lumen;
a balloon including an expandable portion and a balloon leg that are in fluid communication with the primary lumen; and
a guidewire exchange tube extending through the expandable portion and at least partially through the balloon leg, the guidewire exchange tube defining a secondary lumen communicating with the exterior of the catheter; and
a plurality of radiopaque marker bands disposed around the guidewire exchange tube in the balloon leg.
2 . The rapid exchange stent delivery catheter of claim 1 , wherein the balloon leg is more flexible than the catheter shaft.
3 . The rapid exchange stent delivery catheter of claim 1 , wherein the marker bands are evenly spaced apart.
4 . The rapid exchange stent delivery catheter of claim 1 , wherein the marker bands are disposed annularly around the guidewire exchange tube.
5 . The rapid exchange stent delivery catheter of claim 1 , wherein the marker bands number at least three.
6 . The rapid exchange stent delivery catheter of claim 1 , wherein the balloon leg is integral with the expandable portion.
7 . The rapid exchange stent delivery catheter of claim 1 , wherein the balloon leg at least about 2 cm in length.
8 . The rapid exchange stent delivery catheter of claim 1 , further comprising a stent seated on the expandable portion of the balloon.
9 . A method for measuring a dimension of a physiological feature of a mammalian patient, comprising:
inserting a catheter into the vasculature of the patient, the catheter including
a catheter shaft defining a primary lumen;
a balloon including an expandable portion and a balloon leg that are in fluid communication with the primary lumen;
a guidewire exchange tube extending through the expandable portion and at least partially through the balloon leg, the guidewire exchange tube defining a secondary lumen communicating with the exterior of the catheter; and
a plurality of evenly-spaced radiopaque marker bands disposed around the guidewire exchange tube in the balloon leg;
advancing the catheter to a location in the vasculature of the patient, such that the radiopaque marker bands are visible and aligned with the physiological feature; and
determining the dimension of the physiological feature based on a comparison of the dimension of the physiological feature with the position of the marker bands.
10 . The method of claim 9 , wherein the number of marker bands is three or more.
11 . The method of claim 9 , wherein the marker bands are spaced about 1 cm apart.