Stroke Alert: A Review of Current Clinical Stroke Literature

By Matthew E. Fink, MD, Professor and Chairman, Weill Cornell Medical College, and Neurologist-in-Chief, New York Presbyterian Hospital.

Thrombolysis for Ischemic Stroke Associated with Cervical Artery Dissection Does Not Improve Overall Outcome

Source: Engelter ST, et al. Thrombolysis in Cervical Artery Dissection — Data from the Cervical Artery Dissection and Iscaemic Stroke Patients (CADISP) database. Eur J Neurol 2012;1199-1206.

The efficacy of thrombolysis in acute ischemic stroke is well established, but in the subset of patients who have a cervical artery dissection, the data are less clear. Thrombolysis could worsen the situation by increasing the intramural hematoma, or it could be beneficial by helping to recanalize the arterial thrombosis at the site of the dissection. In a multicenter European database of 616 patients with cervical artery dissection and ischemic stroke, analysis of outcome at 3 months (modified Rankin Scale 0-2) and occurrence of "major hemorrhage" (any intracranial hemorrhage and major extracranial hemorrhage) was assessed in patients treated with thrombolysis compared to those who were not. This was on open-label, observational study, where all patients were treated according to the wishes of their treating physicians, and the analysis was performed retrospectively.

Out of a total of 616 patients, 68 (11%) received thrombolysis, and of those, 55 (81%) received the intravenous route. Thrombolyzed patients had more severe strokes (median NIHSS score 16 vs 3; P < 0.001) and more often occlusion of the dissected vessel (66.2 % v. 39.4%; P < 0.001), but after adjustment for stroke severity and vessel occlusion, the chance of favorable outcome was no different between the groups. In matched groups, the odds for good recovery were identical (odds ratio, 1.00; 95% confidence interval, 0.49-2.00). The thrombolyzed group had more serious hemorrhages (5.9% vs 0.6%), but these did not alter outcome or mortality.

 

In Patients with Lacunar Strokes, Addition of Clopidogrel to Aspirin Does Not Reduce Risk of Recurrent Stroke

Source: The SPS3 Trial Investigators. Effects of clopidogrel added to aspirin in patients with recent lacunar stroke. N Engl J Med 2012;367:817-825.

Small subcortical brain infarcts, known as lacu-nar strokes, account for about 25% of all ischemic strokes. They are believed, in most cases, to be caused by disease of small penetrating arteries, i.e., lenticulostriate branches of the middle cerebral arteries, and are the most common cause of "silent" brain infarcts and vascular dementia. Lacunar infarcts were included in studies of intravenous thrombolysis, and they are treated with r-tPA within the appropriate time window. However, secondary prevention of lacunar strokes with antiplatelet therapies has not been specifically studied using MRI as a sensitive method to detect new infarcts.

The Secondary Prevention of Small Subcortical Strokes (SPS3) trial compared two randomized interventions, clopidogrel 75 mg with aspirin 325 mg vs aspirin 325 mg alone in patients who had a lacunar stroke (≤ 2 cm) within 180 days of enrollment. There were 3020 patients enrolled, with a mean age of 63 years, and 63% were men. After a mean follow-up of 3.4 years, the risk of recurrent stroke was not significantly reduced with dual antiplatelet therapy, compared to aspirin alone (2.5% per year vs 2.7% per year). The risk of major hemorrhage was almost doubled with dual antiplatelet therapy vs aspirin alone (2.1% per year vs 1.1% per year; hazard ratio [HR], 1.97). All-cause mortality was increased in the dual antiplatelet therapy group (hazard ratio, 1.52; 95% confidence interval, 1.14-2.04; P = 0.004), but this increase in mortality was NOT accounted for by fatal hemorrhages. In patients with lacunar stroke, the addition of clopidogrel to aspirin did not reduce the risk of recurrent ischemic stroke, but did increase the risk of serious bleeding and death.

 

Risk of Restenosis After Carotid Artery Stenting and Carotid Endarterectomy Are Similar

Source: Lal BK, et al, for the CREST Investigators. Restenosis after carotid artery stenting and endarterectomy: A secondary analysis of CREST, a randomized controlled trial. Lancet Neurol 2012;11:755-763.

In the carotid revascularization endarterectomy versus Stenting Trial (CREST), the overall results of stroke, myocardial infarction, or death during the periprocedural period did not differ between carotid artery stenting (CAS) and carotid endarterectomy (CEA) for either symptomatic or asymptomatic carotid stenosis. This secondary analysis was aimed to compare the overall risk of restenosis of occlusion.

The study enrolled 2191 patients in CREST from 2000 to 2008, and after randomization to either CAS or CEA, their carotid arteries were assessed with duplex ultrasound at 1, 6, 12, 24, and 48 months. Restenosis was defined as a reduction in diameter of the target artery of at least 70%. The frequency of restenosis was calculated by Kaplan-Meier survival estimates, and proportional hazards models were used to assess the association between baseline characteristics and risk of restenosis.

A total of 1086 patients underwent CAS and 1105 underwent CEA. In 2 years, 58 patients who underwent CAS (6.0%) and 62 who had CEA (6.3%) had restenosis or occlusion (hazard ratio [HR], 0.90; 95% confidence interval, 0.63-1.29; P = 0.58). Independent significant predictors of restenosis included female sex (HR = 1.79), diabetes (HR = 2.31), and dyslipidemia (HR = 2.07). Cigarette smoking predicted an increased rate of restenosis after CEA but not after CAS.