Functional polymorphisms in matrix metalloproteinases -1, -3, -9 and -12 in relation to cervical artery dissection.

BACKGROUND: Cervical artery dissection is a leading cause of cerebral ischemia in young adults. Morphological investigations have shown alterations in the extracellular matrix (ECM) of affected vessel walls. As matrix metalloproteinases (MMP) play a central role in the regulation of the ECM, an increased expression of these enzymes might lead to the endothelial damage in spontaneous cervical artery dissection (sCAD). Five different DNA polymorphisms in MMP-1, -3, -9 and -12 were tested for their frequency in patients with sCAD and compared with those of a control population. METHODS: Blood was sampled from 70 unrelated patients presenting consecutively in the department of neurology of the Aachen University Medical School with sCAD and from 87 control subjects living in the same area as the patients. The MMP polymorphisms were analyzed with hybridization probes using the LightCycler (Roche Diagnostics), by sequencing using the ABI 310 Genetic Analyzer (Applied Biosystems) and with the GeneScan program on a ABI 310 Genetic Analyzer. RESULTS: No statistically significant differences in the allelic distribution were found between sCAD patients and the controls. CONCLUSION: Alleles of these 5 functional polymorphisms of MMPs seem not to be associated with structural alterations in the blood vessel wall of sCAD patients. However, this does not exclude a pathogenetic role for MMPs in sCAD via secondary factors such as cytokines that are able to induce these enzymes in cervical blood vessel walls.

The modified Bose method for the endovascular treatment of intracranial atherosclerotic arterial stenoses using the Enterprise stent.

BACKGROUND: Balloon dilatation and deployment of a self-expanding stent is a safe treatment for intracranial atherosclerotic stenoses. The significant recurrence rate might be related to the high radial force of the Wingspan stent. OBJECTIVE: To evaluate the procedural safety and stenosis recurrence rate by the use of a stent with reduced radial force (Enterprise). METHODS: Two hundred nine atherosclerotic stenoses (189 patients) were treated (median age, 68 years; 132 male) in a single center. Lesion locations included internal carotid artery (n = 27), middle cerebral artery (n = 62), vertebral artery (n = 64), basilar artery (n = 55), and posterior cerebral artery (n = 1). Pre- and postmedication included acetylsalicylic acid and Clopidogrel for at least 12 months. Preprocedural and follow-up examinations included magnetic resonance imaging (MRI), neurological assessment, and digital subtraction angiography (6, 12, 26, and 52 weeks). Data registry included age, sex, normal vessel diameter, degree of stenosis, residual stenosis after stent, minimal in-stent diameter, and occurrence of ischemic symptoms during follow-up. RESULTS: Median pre- and postprocedural stenosis rate was 65.4 ± 1% vs 25.1 ± 1%. Technical success rate was 100%. Major procedural complications occurred in 16 patients (8.1%). Combined neurological morbidity and mortality rate at 30 days was 2 patients (0.9%). In 174 stenoses (83%) angiographic follow-up was obtained (mean, 10.2 months). A restenosis (>50%) was observed in 43 (24.7%) cases after 4.2 months (mean) with 4 (9.3%) symptomatic lesions. Incidence of recurrent ischemia related to the stented artery was 2.2% during 10.2 months of mean follow-up. CONCLUSION: Undersized balloon angioplasty and deployment of an Enterprise stent is safe and effective for intracranial stenoses. Follow-up results were equal to or better than those reported for bare-metal balloon-expandable or self-expanding stents and yielded excellent protection from recurrent ischemia.