Transit Scientific Reports Early Clinical Experience With XO Score Sheath Platform

June 30, 2022—Transit Scientific announced findings from the early commercial experience with the XO Score sheath platform that showed successful outcomes on multiple fistula and graft cases using the XO Score devices along with off-the-shelf percutaneous transluminal angioplasty (PTA) balloons.

According to Transit Scientific, the XO Score is a thin one-piece metal alloy exoskeleton sheath with up to 22 struts/grooves that slides over off-the-shelf angioplasty balloons. When the angioplasty balloon is inflated, the struts/grooves expand with the balloon and rotate 90° to apply focal force to the vessel. When the balloon is deflated, the XO struts/grooves rotate 90° back to an atraumatic position and the XO structure assists in balloon rewrap for removal. The XO technology can also be optimized to constrain balloons and prevent torsional and longitudinal shear during angioplasty balloon inflation.

The XO Score system received FDA 510(k) clearance and has European CE Mark clearance to dilate stenotic material in iliac, femoral, iliofemoral, popliteal, infrapopliteal, and renal arteries and for the treatment of obstructive lesions of native or synthetic arteriovenous dialysis fistula.

The company stated that since its introduction XO Score has been instrumental in significant chronic dialysis fistula and graft cases using low-pressure inflation, in some cases after high-pressure PTA treatment failed.

Jeffrey Hoggard, MD, interventional nephrologist at Raleigh Access Center in Raleigh, North Carolina, stated in the company’s press release, “A patient presented with a high-grade stenotic lesion in a brachiocephalic fistula restricting venous outflow. The lesion was resistant to initial treatment using a high-pressure PTA inflated to 40 ATM. The lesion was then treated with the XO Score device and followed by effacement of the stenosis with standard balloon PTA inflated to nominal pressure (9 ATM).”

Dr. Hoggard continued, “There was no residual stenosis and the fistula was no longer pulsatile on exam. XO Score presented a great treatment option for us where high-pressure PTA failed.”

Additionally, the company reported on a case that involved a PTA-resistant lesion in a brachiobasilic graft with flow-restricting outflow stenosis. The lesion failed to respond to a PTA inflated to 22 ATM. Initial treatment was followed up with XO Score over a standard off-the-shelf PTA balloon inflated to nominal pressure (12 ATM). The flow was restored, and no residual stenosis or elastic recoil was present.

Richard Saxon, MD, of the Tri-City Medical Center in San Diego, California, commented in the press release, “I recently noted impressive results using XO Score in a critical recurrent brachiocephalic outflow stenosis and moderate central arch stenosis. The XO Score crossed both lesions without difficulty and allowed for a 5- and 6-mm PTA to be used for effective lesion dilatation with no evidence of posttreatment recoil.

“XO Score introduces a new treatment option to help restore and maintain patency in arteriovenous fistulas and grafts in hemodialysis patients,” concluded Dr. Saxon in Transit Scientific’s press release.