Early ischemic brain lesions after carotid angioplasty and stenting on diffusion-weighted magnetic resonance imaging study
Authors: Misonis Nerijus , Palionis Darius , Tamošiūnas Algirdas , Zabulis Vaidotas , Ryliškienė Kristina , Jatužis Dalius 
Published: January 2014

Aim: The aim of the paper is to evaluate the appearance of the new early ischemic lesions in the brain after carotid angioplasty and stenting on diffusion-weighted magnetic resonance imaging, and their relationship with clinical and procedural factors.

Methods: Carotid artery stenting (CAS) procedures performed by a single interventional cardiologist in years November 2006 to January 2013 were evaluated retrospectively. In total, 227 procedures for 211 patients (mean age 69.8 ± 8.5 years) were performed, from which 171 (75.3%) for male and 56 (24.7%) for female patients. Seventy-two (34.1%) patients had symptomatic stenosis of carotid artery. The following protection systems to avoid the distal microembolism were used during the CAS: (1) Filters: FilterWire EZ (Boston Scientific Corporation); Emboshield NAV (Abbott Vascular); SpideRX (EV3); Defender (Medtronic); FiberNet Filter (Invatec-Medtronic); (2) Occlusion MoMa Baloon System (Invatec-Medtronic). Acute ischemic damages of the brain before and after CAS procedure were diagnosed using magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) sequences. Sixty-five (30.8%) patients underwent MRI test. Exact and asymptomatic χ2 criteria were applied for testing the hypothesis of inter-dependency of the symptoms.

Results: Forty-six (70.8%) patients had new ischemic foci in the brain on MRI DWI after CAS procedures. Among those patients, focal damage of the brain was diagnosed in 36 (78.3%) cases; linear damage of the brain - in 9 (19.6%) patients; ipsilateral damage of the brain - in 37 (80.4%) patients; bilateral damage of the brain - in 16 (34.8%) patients, 38 (82.6%) patients were diagnosed with forebrain damage; 4 (8.7%) patients were diagnosed with damage of brainstem; 5 (10.9%) patients were diagnosed with cerebellum damage. Clinical symptoms of brain damage were diagnosed only for 2 (4.3%) patients. Focal damage of the brain was significantly less frequent only for aortic arch type 1, if compared with aortic arch type 2 and 3: 64.3%, 93.3% and 100.0%, respectively (p < 0.05). Focal damage of the brain occurred least in patients (28.6%) with Emboshield NAV protection type, if compared to other types of protection (71.4-100.0%). Linear >10mmbrain damage was less frequent when using FilterWire EZ, Emboshield NAV and SpideRX protection type. Ipsilateral ischemic brain damage also occurred less frequent when using Emboshield NAV protection type; bilateral damage occurred less frequent when using FilterWire EZ, Emboshield NAV and SpideRX protection type. Ischemic forebrain damage was also diagnosed less often in patients for whom protection type FilterWire EZ and Emboshield NAV was applied.

Conclusions: Most frequent findings by MRI after CAS procedures were focal, ipsilateral and forebrain damage (about 80%), but less than 5% patients had clinical symptoms. In the case of aorta arch type 1 focal ischemic damage of the brain was significantly less frequent, then in aortic arch type 2 and 3. The localization and extent of brain damage was associated with the type of protection systems that have been used.