Microcatheter sensor design for minimizing profile and impact of wire strain on sensor

Patent metadata

Field	Value
Publication number	US-11701012-B2
Application number	US-202117176629-A
Country	US
Kind code	B2
Filing date	Feb 16, 2021
Priority date	Jun 16, 2014
Publication date	Jul 18, 2023
Grant date	Jul 18, 2023

Abstract

A catheter, such as a fractional flow reserve catheter, includes an elongate shaft having a pressure sensing wire extending to the distal portion of the elongate shaft. The wire has a pressure sensor mounted on the distal end for measuring a pressure of a fluid within lumen of vessel. The pressure sensor wire is disposed within a pocket formed adjacent to the pressure sensor thereby minimizing the profile of the catheter. Bending stresses experienced by a pressure sensor mounted to a fractional flow reserve catheter when tracking the catheter through the vasculature creates a distortion of the sensor resulting in an incorrect pressure reading or bend error. In order to isolate the sensor from bending stresses, the sensor is spaced apart from the pressure sensor wire to allow the pressure sensor and the pressure sensor wire to move independently from one another.

First claim

What is claimed is:

1. A catheter comprising:
an elongate shaft including a proximal portion and a distal portion, the elongate shaft having a shaft wall, the shaft wall having a shaft wall outer surface and a shaft wall inner surface, the shaft wall inner surface defining a guidewire lumen, further wherein the shaft wall defines a pressure sensor wire lumen,
a communication wire extending proximally through the pressure sensor wire lumen;
a pressure sensor coupled to the shaft wall outer surface at the distal end of the elongate shaft, wherein the pressure sensor is spaced apart from a distal end of the communication wire forming a gap along the shaft wall outer surface;
electrical couplings provided in the shaft wall along the length of the gap and configured to electrically couple the pressure sensor with the communication wire,
wherein the communication wire is electrically coupled with the electrical couplings at an outer surface of the shaft wall and the pressure sensor and the communication wire are configured to move independently from one another in response to bending forces of the shaft wall resulting from when the elongate shaft is tracked to a treatment site within a vasculature.

2. The catheter of claim 1 , wherein the pressure sensor has first and second surfaces, further wherein the pressure sensor is mounted to a step on the second surface of the pressure sensor, the step extending from the shaft wall.

3. The catheter of claim 2 , further comprising a bonding member having one end electrically coupled to the first surface of the pressure sensor, the bonding member having a second end electrically coupled to the shaft wall outer surface of the gap.

4. The catheter of claim 2 , wherein one end of the pressure sensor is mounted to the step and another end of the pressure sensor is spaced apart from the shaft wall.

5. The catheter of claim 1 , wherein the electrical couplings are etched into the outer surface of the shaft wall outer surface along the length of the gap.

6. The catheter of claim 1 , wherein the electrical couplings are formed from a metallization of the outer surface of the shaft wall outer surface along the length of the gap.

7. The catheter of claim 6 , wherein the distal end of the elongate shaft includes a doped polymer configured for activation for selective plating by laser direct structuring.

8. The catheter of claim 1 , wherein the electrical couplings are integrated within the shaft wall.

Assignees

• Medtronic Vascular Inc

Inventors

• Mccaffrey Gerry
• Murphy Christopher
• Ward Sean
• Sweeney Fiachra

Classifications

• A61B5/02141 Primary

  Details of apparatus construction, e.g. pump units or housings therefor, cuff pressurising systems, arrangements of fluid conduits or circuits (A61B5/02233, A61B5/0235 take precedence) · CPC title

• A61B5/02007

  Evaluating blood vessel condition, e.g. elasticity, compliance · CPC title

• A61B5/0215

  by means inserted into the body · CPC title

• A61B5/6852

  Catheters · CPC title

• A61B2562/0247

  Pressure sensors · CPC title