As the debate rages as to the most appropriate design for carotid stents, at the recent EuroPCR meeting in Barcelona, Spain, Dr Alberto Cremonesi, Cotignola, Italy, presented data from the CRISTALLO trial. This is a prospective, multi-centre registry designed to evaluate the safety and performance of the new Cristallo Ideale carotid stent (Invatec) with a protection device (filter of proximal) for the treatment of common and/or internal carotid artery stenosis.
This ‘hybrid’ nitinol stent combines ‘open’ cell design at the proximal and distal sections enhancing conformability, flexibility and reducing radial force in the healthy vessel segments. In addition, the ‘closed’ cell design in the central part secures the appropriately high scaffolding at the lesion site preventing plaque prolapse. The stent is delivered via a unique 5F introducer rapid exchange sheath that is highly-compatible and flexible and has ‘excellent’ trackability to treat challenging anatomies. The ergonomic handle allows for easy and accurate one-handed deployment and one radiopaque marker inside each end of the stent enhances visibility and avoids the entrapment of interventional tools when recrossing the stent.
The primary endpoint of the study was incidence of device or procedure related major or minor adverse neurological events (MANE) through 30 days. The secondary endpoints were technical success (defined as the ability to deploy the Cristallo Ideale stent in the target lesion with the residual diameter stenosis <30%) and procedural success (defined as technical success free of procedural MANE). Inclusion criteria was de novo or post carotid endarterectomy restenotic target lesion, suitable for balloon angioplasty/stenting, as well as the morphological feasibility to use the Mo.Ma proximal flow device (Invatec) or any other filter protection device. The reference vessel diameter for stent placement is 4mm distal and <10mm proximal. Exclusion criteria included acute stroke within 14 days prior to the procedure or a major residual neurological deficit, a secondary vessel to be treated during the same procedure and an underlying disease other than atherosclerosis. A total of 124 symptomatic and asymptomatic patients were enrolled in four centres (three in Italy, one in Germany). Stent length of 30mm was used in 24.19% of patients and 40mm in 75.81% of patients, with post-dilatation performed in 97.58% of the procedures. Distal filters were used in 41.13% of the procedures and the Mo.Ma device in 58.87% of the procedures. The technical success rate was 100% in spite of several unfavourable anatomies and there were no reported minor or major neurological events. In conclusion, Cremonesi said, “In centres where serious training and credentialing programme in endovascular procedures represents the standard of care, this new hybrid stent concept fitting unselected anatomies allowed operators to achieve exceptionally high safety standards.”