ARMOUR study assess Mo.Ma proximal protection system.
The first patient treated in the ARMOUR (proximAl pRotection with the Mo.Ma device dUring caRotid stenting study) trial, sponsored by Invatec. The procedure was performed by Dr Michael Bacharach, North Central Heart Institute, Sioux Falls, SD, on a patients deemed at ‘high-risk’ for surgery. The trial is assessing the Mo.Ma proximal flow blockage embolic protection system. A total of 228 patients at high increased risk of complication during carotid endarterectomy will be recruited under the guidance and supervision of the Co- Principal Investigators, Drs Gary Ansel, Riverside Methodist Hospital, Columbus, OH, and L Nelson Hopkins, University of Buffalo, Buffalo, NY. Study enrollment is anticipated to occur at 20 sites in the US and Europe using the Mo.Ma proximal protection device in combination with FDA approved carotid stents. The Mo.Ma device is used to perform protected carotid stenting, achieving cerebral protection by endovascular clamping of both the common carotid artery (CCA) and the external carotid artery (ECA). The device removes particulate debris by aspiration. It emulates the surgical clamping technique through simultaneous endovascular occlusion of both the CCA (up to 13mm) and the ECA (up to 6mm), via two independently inflatable compliant balloons. Blood flow at the site of carotid intervention is blocked before a guidewire is advanced across the lesion. The basic component of the system is a one-piece 90cm long guiding catheter with a 2.1mm (6F) central lumen, wide enough for the insertion of all common interventional devices, injection of contrast dye and the effective aspiration of particles. The exit port of the working channel is located between the two balloons just distal of the proximal balloon for occlusion of the CCA. The Italian PRIAMUS registry has previously evaluated the applicability and efficacy of the Mo.Ma device in a real world population. PRIAMUS recruited 416 patients (300 men; mean age 71.6±9 years) between October 2001 and March 2005, in four Italian centers. The trial included 264 symptomatic patients (63.5%) with >50% stenosis and 152 asymptomatic patients (36.5%) with >70% stenosis. The results of the PRIAMUS registry showed that technical success, defined as the ability to establish protection with the Mo.Ma device and to deploy the stent, was achieved in 412 cases (99%). The mean duration of flow blockage was 4.91±1.1 minutes. Transient intolerances to flow blockage were observed in 24 patients (5.7%), but in all cases the procedure was successfully completed. No peri-procedural strokes or deaths were observed and complications during hospitalization included 16 minor strokes (3.84%), three transient ischemic attacks (0.7%), two deaths (0.5%) and one major stroke (0.2%). This resulted in a cumulative rate at discharge of 4.6% all strokes and deaths, and of 0.7% major strokes and deaths. All the patients underwent 30-day follow-up. At 30-day follow-up, there were no deaths and no minor and major strokes, confirming the overall cumulative incidence. In 245 cases (58.9%) there was macroscopic evidence of debris after filtration of the aspirated blood. The Italian multi-center registry confirmed and supported the efficacy and applicability of the endovascular clamping concept with proximal flow blockage in a broad patient series, and the results match favorably with current available studies on carotid stenting with cerebral protection. The ARMOUR, study is intended to pave the way for FDA clearance of the Mo.Ma device. Mo.Ma is available in 9F and 8F, featuring 6F and 5F inner lumen respectively. The 9F version will be used in the ARMOUR study to allow usage of the 6F FDA approved carotid stents.