Indication for Use
The Covera™ Vascular Covered Stent is indicated for use in hemodialysis patients for the treatment of stenoses in the venous outflow of an arterio-venous (AV) fistula and at the venous anastomosis of an ePTFE or other synthetic AV graft.
Contraindications
There are no known contraindications for the Covera™ Vascular Covered Stent.
Warnings
This device should be used only by physicians who are familiar with the complications, side effects, and hazards commonly associated with dialysis access shunt revisions and endovascular procedures. • DO NOT expose the covered stent to temperatures higher than 500 °F (260 °C). ePTFE decomposes at elevated temperatures, producing highly toxic decomposition byproducts. • DO NOT use the device if packaging / pouch is damaged. • The Covera™ Vascular Covered Stent device is supplied STERILE and is intended for SINGLE USE ONLY. DO NOT RESTERILIZE AND/OR REUSE this device. • DO NOT use in patients with uncorrectable coagulation disorders. • DO NOT use in patients with bacteremia or septicaemia and/or evidence of fistula or graft infection. • DO NOT use in patients that cannot be adequately premedicated and have a known allergy or sensitivity to contrast media. • DO NOT use in patients with known hypersensitivity to nickel-titanium or tantalum. • DO NOT use in an immature fistula or in patients whose AV Access grafts have been implanted less than 30 days. • DO NOT use the device in patients where full expansion of an appropriately sized PTA balloon catheter could not be achieved during pre-dilation with an angioplasty balloon. • Placing a covered stent across a vessel side branch may impede blood flow and hinder or prevent future procedures. • Covered stent placement beyond the ostium of the cephalic vein into the axillary/subclavian vein may hinder or prevent future access. • DO NOT place a flared covered stent with the flared end in a straight vessel segment since this may lead to flow turbulences. The flared end is not intended to provide additional device fixation.
Precautions
Prior to covered stent implantation, read the instructions for use and refer to the sizing table contained therein. Careful attention should be paid to ensure the device is appropriately sized to the vessel diameter, taking into account any change in the vessel diameter that may have resulted from previous interventions. For an AV graft access, utilize the graft diameter as the reference vessel and for an AV fistula access, utilize the inflow vein diameter as the reference vessel. • The appropriate length device should be selected so that the stent graft extends beyond the stenosis into at least 5 mm of the non-diseased fistula or graft towards the arterial inflow and into the non-diseased vein approximately 5 mm beyond the stenosis. • The delivery system is not intended for any use other than covered stent deployment. • The covered stent (implant) cannot be repositioned after total or partial deployment. • Once partially or fully deployed, the covered stent cannot be retracted or remounted onto the delivery system. Device removal after deployment can only be done with a surgical approach. • If unusual resistance is met during covered stent system introduction, the system should be removed and another covered stent system should be used. • DO NOT introduce, manipulate or remove the delivery system without an appropriately sized guidewire in place and without fluoroscopic guidance. • DO NOT kink or use a kinked delivery system. • During covered stent release DO NOT hold the 30 cm long distal catheter assembly segment as it must be free to move and slide into the white stability sheath. • Careful attention by the operator is warranted to mitigate the potential for distal migration of the covered stent during deployment. • Post dilation of the covered stent must be performed using an appropriately sized PTA balloon catheter to avoid damage to the covered stent. The covered stent cannot be post dilated beyond its labelled diameter. The flared distal end does not require post dilation. • The effect of placing the device across an aneurysm or a pseudoaneurysm has not been evaluated. • The effect of using the device in central veins has not been evaluated. • The effect of placing the device across a previously placed bare metal stent has not been evaluated. • The effect of placing the device across the antecubital fossa has not been evaluated. • The effect of using the device in pediatrics has not been evaluated. • The effect of using the device across the anastomosis of an AV fistula has not been evaluated. • Vessel angulation was not measured as part of the clinical study, as such limitations in covered stent angulation are unknown. • DO NOT cannulate the covered stent. Notify the patient that the covered stent should not be directly cannulated for hemodialysis and that applying pressure to the implant area should be avoided. • The device has not been tested for use in an overlapped condition with a bare metal stent or covered stent. • Higher deployment force may be encountered with longer length covered stents. • The device has not been tested for tracking and deployment around an AV loop graft. • Serious complications, such as migration to the heart or lungs, may occur post-discharge when covered stents have not been appropriately sized. • Stent graft dislodgement may occur during removal of the delivery system; therefore, careful attention should be paid during this portion of the procedure to prevent such occurrences.
Potential Complications and Adverse Events
Complications and Adverse Events associated with the use of the Covera™ Vascular Covered Stent may include the usual complications associated with endovascular stent and covered stent placement and dialysis shunt revisions. Potential complications may include, but are not limited to: New lesions in the access circuit requiring reintervention; thrombotic occlusion; restenosis of the target lesion requiring reintervention; pseudoaneurysm; vessel rupture; dissection; extravasation; perforation; pain; infection; hemorrhage; hematoma; arm or hand edema; steal syndrome; congestive heart failure; cerebrovascular accident; allergic reaction; rash; reaction to contrast; fever; sepsis; prolonged bleeding, ventricular fibrillation; face or neck edema; bleeding at access site; numbness; venous spasm; hemoptysis and death.