Crossing Total Occlusions Using a Hydraulic Pressure Wave: Development of the Wave Catheter

Area of Science:

• Biomedical Engineering
• Medical Devices
• Surgical Robotics

Background:

• Miniaturization of surgical instruments presents challenges in applying sufficient force for tissue resection.
• Slender surgical tools are prone to buckling, limiting their effectiveness in procedures requiring high force application.

Purpose of the Study:

• To develop an innovative cardiac catheter capable of applying high forces on target tissues without buckling.
• To investigate the use of hydraulic pressure waves for force transmission through slender surgical instruments.

Main Methods:

• Developed a 5F cardiac catheter (1,000 mm length) utilizing a hydraulic pressure wave system.
• The catheter shaft comprises a flat wire coil, double braid, and nylon outer coating for flexibility and strength.
• A COMSOL model was used to simulate hydraulic pressure waves; a solenoid actuator controlled impulse characteristics (frequency, time, strokes).

Main Results:

• The Wave catheter successfully applied forces up to 9.0 ± 0.2 N without buckling.
• Penetrated a phantom model of a coronary Chronic Total Occlusion (CTO).
• Reduced puncture time from 80 ± 5.4 s to 7.8 ± 0.4 s with stroke frequencies of 1-10 Hz.

Conclusions:

• The developed Wave catheter enables high force application through slender shafts, overcoming limitations of current surgical instruments.
• This technology represents a significant step towards improving the efficacy of minimally invasive surgical procedures.
• The catheter's design allows for single-handed operation and adjustable impulse characteristics for versatile clinical application.