Intravascular devices, systems, and methods having drive cables with a lubricious coating and/or radiopaque markers
Rotational intravascular ultrasound (IVUS) imaging devices and systems are provided. The IVUS imaging devices include catheters having a rotating drive cable with a transducer disposed at a distal end thereof for imaging a bodily vessel of interest. In some embodiments, a lubricious coating is applied on the drive cable to promote uniform rotation of the drive cable and the transducer. In some embodiments, the drive cable is coated with a polymer layer to promote uniform rotation of the drive cable and the transducer. In some embodiments, radiopaque markers are affixed on the drive cable for accurate placement of the transducer within of the vessel and for accurate measurement of internal dimensions and lesion lengths within the body of the patient.
1. A rotational IVUS device, comprising:
a drive cable configured to rotate about an axis of rotation associated with the IVUS device, the drive cable comprising a proximal end, a distal end, a length from the proximal end to the distal end, and a flexible coil extending from the proximal end to the distal end, the flexible coil configured to transfer a rotational force along the length of the drive cable; and
a transducer coupled to the distal end of the flexible coil such that the transducer rotates with the drive cable,
wherein the flexible coil of the drive cable includes a single length of material formed into an alternating series of tightly wound sections and loosely wound sections such that the tightly wound sections are a plurality of radiopaque markers spaced from one another along the length of the drive cable.
2. The rotational IVUS device of claim 1 , wherein the plurality of radiopaque markers extend along the drive cable from adjacent to the distal end to adjacent to a proximal end.
3. The rotational IVUS device of claim 1 , wherein the plurality of radiopaque markers are of equal size.
4. The rotational IVUS device of claim 1 , wherein the plurality of radiopaque markers are of variable size.
5. The rotational IVUS device of claim 1 , wherein the plurality of radiopaque markers are spaced equidistantly along the drive cable.
6. The rotational IVUS device of claim 1 , wherein the plurality of radiopaque markers are variably spaced along the drive cable.
7. The rotational IVUS device of claim 1 , wherein a width of a radiopaque marker, from among the plurality of radiopaque markers, is proportional to a distance between two adjacent radiopaque markers from among the plurality of radiopaque markers.
8. The rotational IVUS device of claim 1 , wherein the tightly wound sections comprise areas of a closed pitch and the loosely wound sections comprise areas of an open pitch.
9. The rotational IVUS device of claim 1 , wherein the flexible coil is hollow.
10. The rotational IVUS device of claim 9 , wherein the drive cable is coated with a lubricious coating configured to enable uniform rotation of the drive cable and the transducer by reducing frictional forces experienced by the drive cable.
11. The rotational IVUS device of claim 9 , further comprising a polymer layer fixedly secured to and surrounding the drive cable without enclosing the transducer, wherein the polymer layer is configured to enable uniform rotation of the transducer by reducing frictional forces experienced by the drive cable.
12. The rotational IVUS device of claim 1 , wherein the tightly wound sections comprise a first pitch along a lengthwise direction of the drive cable and the loosely wound sections comprise a second pitch along the lengthwise direction, the first pitch being smaller than the second pitch.
13. The rotational IVUS device of claim 12 , wherein the first pitch is a closed pitch and the second pitch is an open pitch.