Farm and Cordis, a Cardinal Health company, collaborated on the INCRAFT AAA Stent-Graft System, a new repair technology for the treatment of AAA where up to three, low-profile stents are placed inside the damaged area of the patient’s aorta. Once installed, the stent system acts as a structural liner to prevent a rupture.
The project began by observing multiple AAA repair procedures to understand the unique challenges. The arterial path through which the surgeon pushes the catheter has a convoluted shape, and the stents are deployed where the blood flow is strongest. To address the forces working against the surgeon, our team created handle concepts with varied cross-sections and surface features and preference-tested them with endovascular surgeons. Their feedback guided us in designing a handle whose shape gives the surgeon better leverage to resist twisting forces, and molded-in ribs to make the handle easier to grip with wet hands as the catheter is being moved inside the patient. To resist the torque working against the catheter as it travels through the artery, our engineers designed a unique torsionally stiff internal drive system using a pair of extruded, arc-shaped rails on which the drive element travels as the stent is deployed. To achieve the desired linear motion, we incorporated a large diameter, multi-start drive nut whose outer threads act against matching threads on the interior surface of the handle. This elegantly simple design supplies substantial rotational torque, while giving the surgeon a high level of linear motion for a given rotation of the handle. This rotational action makes it easier to unsheathe the stent, while reducing the effect of back-pressure and preventing accidental deployment.
Some of the other enhancements Farm incorporated into the new INCRAFT device:
- Both auditory and tactile feedback on how much of the sheath has been uncovered.
- A two-button unlocking feature that prevents accidents by forcing the surgeon to deliberately unlock the tool before proceeding to the next step in the procedure.
- A convenient port in the base of the handle that allows the surgeon to inject contrast fluid directly into the procedure site.
The INCRAFT System is cleared for use and now available in Europe, Canada, Mexico, Colombia and Brazil.
