Posterior Circulation Ischemic Stroke Caused by Arterial Dissection: Characteristics and Predictors of Poor Outcomes.

BACKGROUND: Posterior circulation ischemic stroke (PCS) caused by arterial dissection (AD-PCS) was rarely discussed. The present study aimed to evaluate the clinical characteristics and predictors of poor outcomes in AD-PCS patients. METHODS: A total of 286 PCS patients were recruited from Taipei Veterans General Hospital Stroke Registry (between January 1, 2012 and February 28, 2014). Clinical/image data of recruited PCS patients were reviewed by stroke specialists who reached a consensus on the stroke etiologies. Data of AD-PCS patients were analyzed. RESULTS: Seventy-four patients (65.8 ± 15.6 years, 56 (75.7%) men) were determined as AD-PCS. Headache and neck pain at admission were only presented in 18.9 and 6.8% of patients, respectively. The location of AD was initiated in the vertebral artery (66.2%), basilar artery (27.0%), posterior inferior cerebellar artery (5.4%) and posterior cerebral artery (1.4%). The involvement of intracranial arteries was present in the majority of patients (97.3%). Of the patients, 9.5% died, and 29.7% had poor functional outcomes (modified Rankin Scale ≥4) at 3-month. Conscious change independently predicted mortality at 3 months. Quadriparesis, National Institutes of Health Stroke Scale (NIHSS) score >8 and infarct lesions involving >1 category were independent predictors for poor functional outcomes at 3 months. CONCLUSION: AD is an important etiology of PCS. Physicians should be more vigilant in recognizing AD-PCS. Intracranial arteries are more important in AD-PCS; very few patients of AD-PCS had dissection solely in extracranial arteries. Short-term outcomes of AD-PCS were not favorable. Conscious change, quadriparesis, NIHSS score >8 and infarct lesions involving >1 category were independent predictors for poor outcomes. Patients presenting these factors should be monitored closely.

Stroke etiology is associated with outcome in posterior circulation stroke.

OBJECTIVE: Stroke research and clinical trials have focused mainly on anterior circulation stroke (ACS). Since clinical characteristics, mechanisms, and outcomes of posterior circulation stroke (PCS) have been reported different from ACS, more PCS studies are required, particularly researching the etiologies, to help establish an optimal management strategy. METHODS: The present study analyzed patients of PCS who were consecutively admitted and registered in Taipei Veterans General Hospital Stroke Registry between 1 January 2012 to 28 February 2014. We demonstrated the distribution of etiologies, compared the clinical characteristics/outcomes among different etiology groups, and used univariate/multivariate analyses to identify the predictors for poor functional outcome (modified Rankin Scale ≥5) at discharge and 3 month. RESULTS: About 286 patients of PCS were included for analyses. Basilar artery atheromatous branch occlusive disease (BABO, 28.0%) and large artery dissection (25.9%) were the two most common etiologies, followed by large artery atherosclerotic stenosis/occlusion (LAA, 20.6%), cardioembolism (CE, 18.5%) and small vessel disease (7.0%). Age, vascular risk factors, infarct locations and patterns, and outcomes were different among these five etiology groups. Multivariate analyses showed that age >70 y/o (discharge/3 month, OR, 95% CI: 3.05, 1.23-7.56/8.39, 2.32-30.33), admission NIH Stroke Scale >9 (19.50, 8.69-43.75/13.45, 5.59-32.39), and etiology (LAA versus BABO: 5.00, 1.58-15.83/4.00, 1.19-13.4; CE versus BABO: 3.36, 1.02-11.09/4.66, 1.40-15.46) were independently associated with poor functional outcome. INTERPRETATION: The etiologies of PCS are heterogeneous and shown to be associated with functional outcomes. Our results have shed lights on future pathophysiological research and designs of clinical trials for PCS.