Introducing the Safe-Cross CTO System with RF and OCR Technology

Crossing Chronic Total Occlusions (CTOs) remains one of the most challenging interventional procedures.  The primary objective in the successful treatment of opening CTOs is crossing the lesion with a guide wire.  The Safe-Cross Radio Frequency (RF) Total Occlusion Crossing System is among the first innovative technologies for the treatment of CTOs.  The Safe-Cross System is an innovative technology because it combines power ablation technology and guidance into one interventional device. The Safe-Cross System is a guide wire based platform, providing RF energy to power the guide wire through the occlusion. The optical guidance allows the RF energy to be safely delivered within the lumen of the artery.

RF Energy:  Provides the ability to give micro-bursts of energy to create a passage through the CTO. 

The RF energy feature of the Safe-Cross System is an adaptation of a well-known technique in medicine known as electrosurgery.  Very high voltage is delivered in pulses within less than a second to the tip of the wire.  The pulsed RF energy causes arcing that vaporize and fracture the plaque.  Because of the delicate nature of the cardiac and peripheral arteries, the Safe-Cross System uses much less power than traditional electrosurgery devices.  By pulsing RF energy, less heat is generated while the desired effect is achieved.


Optical Coherence Reflectometry:  Provides guidance while acting as a safety mechanism that allows the operator to identify when the wire tip is in proximity to the artery wall.
 
The guidance system provided by the Safe-Cross System is based on a principle called optical coherence reflectometry (OCR), which is a subset of a larger better-known technology called optical coherence tomography (OCT).  OCT is a relatively new technology, which was first, demonstrated in 1991, and has since found use as an imaging technique for several biomedical applications, most notably in the area of ophthalmology.

OCR is similar to ultrasound, but uses near-infrared light instead of sound to create much better resolution.  The light from the tip of the guide wire is projected at the tissue inside the artery.  The light has the ability to penetrate through the arterial plaque to reach the artery wall, and then be reflected. The reflectivity off the artery wall is significantly higher than that of the arterial plaque, and the Safe-Cross System is designed and calibrated to measure this difference in reflectivity, which is graphically displayed.


Steerability:  Since the initial release of the Safe-Cross System, a more steerable .014” wire has been developed.  This new design is available in a shapeable straight tip and an angle tip wire.  

The Safe-Cross guide wire is designed to deliver  RF energy and transmit optical signals, while maintaining the feel of a coronary guide wire. The basis for the design is a stainless steel hypo tube (.014” OD x .007” ID), which contains an optical fiber within its inner diameter.  Special coatings on its outer diameter which serve to deliver the electrical energy at the tip of the wire. 

Results:  By treating CTOs interventionally and restoring blood flow through the artery, the patients quality of life improves.