High Incidence of Atrial Fibrillation After Embolic Stroke of Undetermined Source in Posterior Cerebral Artery Territory.

BACKGROUND: Subclinical atrial fibrillation is one possible cause of embolic stroke of undetermined source (ESUS). It remains to be elucidated if a specific infarction site has a predictive value for detecting subclinical atrial fibrillation. We aimed to investigate the predictive value of infarction site in patients with ESUS for the detection of atrial tachyarrhythmia (AT) using an insertable cardiac monitor. METHODS AND RESULTS: Consecutive 146 patients (84 men; aged 62±12 years) underwent insertable cardiac monitor implantation after diagnosis of ESUS. The detection of AT >30 seconds was evaluated. The ESUS infarction sites were categorized into internal carotid artery and vertebral artery (VA) territories, with ophthalmic artery, anterior cerebral artery, and middle cerebral artery as internal carotid artery subterritories, and posterior cerebral artery and other vertebrobasilar arteries as VA subterritories. During a median follow-up of 387 days, AT was detected in 33 patients (23%). Subclinical AT detection was significantly more frequent after VA territorial infarction opposed to internal carotid artery infarction (20/57 [35%] versus 13/89 [15%]; P=0.0039). Kaplan-Meier analysis demonstrated a significantly higher AT detection rate after VA infarction (log-rank, P=0.0076). Regression analysis revealed that VA territorial infarction, and particularly posterior cerebral artery area infarction, was an independent predictor of AT detection. CONCLUSIONS: Patients with ESUS in the posterior cerebral artery territory had a higher rate of subclinical AT detection than those with other infarct localizations. Our data suggest that the possible usefulness of ESUS site to identify candidates for direct oral anticoagulation should be confirmed in future research.

Long-term outcomes in adult patients with ischemic-type moyamoya disease involving posterior circulation.

BACKGROUND: The object of this study was to compare the long-term outcomes in adult patients with moyamoya disease (MMD) with posterior circulation involvement (PCi) treated through surgical revascularization with those in adult patients without PCi. METHODS: The records of 32 consecutive adult patients with ischemic-type MMD who were treated with revascularization were reviewed. Twelve of these patients (38 %) had PCi at initial onset. Clinical characteristics of the patients with PCi were compared to those without PCi. Neurological outcomes were assessed using the modified Rankin Scale (mRS) in the preoperative and postoperative follow-up periods. A five-year Kaplan-Meier stroke risk was calculated. RESULTS: The frequency of presenting with infarction was significantly higher among patients with PCi than among those without PCi (p = 0.006). mRS scores in the preoperative period were significantly higher in patients with PCi than in patients without PCi (p = 0.0004). There were no significant differences in mRS scores between the preoperative and postoperative follow-up period in patients with PCi (p = 0.3), nor were there any between the preoperative and postoperative follow-up periods in patients without PCi (p = 0.2). The five-year Kaplan-Meier risk of surgical morbidity and ipsilateral stroke was 14.3 % in surgically treated hemispheres with PCi versus 14.9 % in surgically treated hemispheres without PCi (p = 0.96). CONCLUSIONS: PCi at initial onset was significantly correlated with poor outcome. Revascularization for the middle cerebral artery territory in patients with PCi was effective at preventing recurrent ischemic stroke.

Long-term outcome in posterior cerebral artery stroke.

INTRODUCTION: Previous studies on posterior cerebral artery (PCA) strokes focused mainly on topography and underlying pathophysiology. However, there are no data on long-term prognosis and its association with the localization of the infarct. METHODS: All consecutive PCA strokes registered in the Athens Stroke Outcome Project between 01/1998 and 12/2009 were included in the analysis. The New England Posterior Circulation Registry criteria were applied to classify them in relation to topography: (i) pure PCA infarcts, including pure cortical-only and combined cortical/deep PCA infarcts (groups A and B respectively), and (ii) PCA-plus strokes, including cortical-only and combined cortical/deep PCA strokes with ≥1 concomitant infarcts outside PCA territory (groups C and D respectively). Patients were prospectively followed up to 10 years after stroke. RESULTS: Amongst 185 (8.1%) PCA patients that were followed up for 49.6±26.7months, 98 (53%), 24 (13%), 36 (19.5%), and 27 (14.6%) were classified in group A, B, C, and D, respectively. Infections and brain edema with mass effect were more frequently encountered in PCA-plus strokes compared to pure PCA (P<0.05 and <0.01 respectively). At 6 months, 56% of cortical-only PCA patients had no or minor disability, compared to 37%, 36%, and 26% in the other groups (P=0.015). The 10-year probability of death was 55.1% (95%CI: 42.2-68.0) for pure PCA compared to 72.5% (95%CI: 58.8-86.2) for PCA-plus (log-rank 14.2, P=0.001). Long-term mortality was associated with initial neurologic severity and underlying stroke mechanism. CONCLUSIONS: Patients with pure PCA stroke have significantly lower risk of disability and long-term mortality compared to PCA strokes with coincident infarction outside the PCA territory.

Stroke of the posterior cerebral circulation.

AIM: Identification of stroke etiology aids in developing secondary prevention and treatment strategies for posterior circulation stroke (PCS). Studies have identified large vessel atherosclerotic disease as the predominant etiology and others have cited cardioembolism. This study was designed to describe the prevalence, outcome, and stroke mechanisms of PCS and to analyze the strengths and weaknesses of the classifications used. METHODS: A comprehensive MEDLINE search identified seven studies evaluating the etiology of PCS. Incoherent data and lack of prospective studies made performance of a thorough meta-analysis impossible. Special attention was paid to the design of trials and the classifications used. In a similar way, the limitations of each study were clearly determined. RESULTS: Seven trials encompassing 8057 patients, of which 23% were isolated PCS and 4% were combined ACS and PCS, were analyzed. Overall, large vessel atherosclerotic disease was responsible for 35% of PCS, cardioembolism for 18%, small vessel disease for 13% and undetermined etiology for 15%. Strokes of mixed and "other" etiology represented 4% and 8% of PCS respectively. Major sequelae were observed in 10.8-17.7% of patients with no sequelae noted in 7-28% of patients. Mortality ranged from 4-10% and it was directly related to stroke in 2-5%. CONCLUSION: Large vessel atherosclerotic disease was the most common stroke subtype identified. Conclusions are inconsistent between the studies, highlighting the difficulties in systematic investigations of stroke etiology and the need for a unified approach to stroke classification.

Intravenous thrombolysis in posterior cerebral artery infarctions.

BACKGROUND: Approximately 5-10% of all acute ischemic strokes (AIS) occur in the territory of the posterior cerebral artery (PCA). Little is known about intravenous thrombolysis (IVT) in this infarct subgroup in terms of outcome and intracerebral hemorrhage rates. The aim of our study was to evaluate differences between supratentorial PCA infarcts and anterior circulation infarcts regarding baseline characteristics, stroke severity, outcome, safety and clinical findings, which would implicate a change in the existing thrombolysis practice in patients with PCA stroke. METHODS: All patients with AIS in the supratentorial PCA territory receiving IVT between 01/2006 and 01/2010 were selected from the Erlangen Thrombolysis Database (group 1, n = 21). They were compared to all IVT patients with strokes in other supratentorial vascular territories over the same period of time (group 2, n = 398). Baseline demographic data, as well as clinical and laboratory findings were analyzed. The outcome was assessed using the modified Rankin Scale at 3 months. RESULTS: Only serum glucose levels at baseline (110.5 ± 36.1 vs. 127.2 ± 48.2 mg/dl; p = 0.036) and the baseline National Institutes of Health Stroke Scale score (median 6.5 vs. 9; p = 0.016) were significantly lower in group 1 compared to group 2. Favorable clinical outcome (57.1 vs. 48.6%; p = 0.445) and intracerebral hemorrhage rates (4.8 vs. 4%; p = 1.000) were comparable in both groups. CONCLUSIONS: No substantial differences were found between supratentorial PCA and anterior circulation infarcts. Our data on safety and efficacy support the present common thrombolysis practice in supratentorial PCA infarct patients, though an indication for IVT should rather be based on the existence of functionally disabling deficit than merely on the National Institutes of Health Stroke Scale.

One-year case fatality and disability after posterior circulation infarction in a Chinese hospital-based stroke study.

BACKGROUND AND PURPOSE: Controversy exists as to whether posterior circulation infarction (PCI) has a poorer outcome compared to anterior circulation infarction (ACI). We aimed to investigate whether PCI had different clinical outcomes from ACI in Chinese patients with ischemic stroke. METHODS: Data on ischemic stroke patients with ACI or PCI were collected including demographics, risk factors and 1-month, 3-month, and 1-year case fatality and disability (defined as modified Rankin Scale 3-5). Multivariate regression models were used to analyze predictors for death and disability. RESULTS: Of the 1,962 enrolled cases, 433 (22.1%) had PCI. The case fatality of PCI at 1-month, 3-month and 1-year follow-up (FU) were lower than that of ACI (3.93, 5.3 and 9.7% vs. 7.26, 9.3 and 13.7%, p <0.05), and the proportion of disability was also lower in PCI at 3-month FU (19.6 vs. 29.1%, p<0.001) and 1-year FU (6.5 vs. 15.2%, p<0.001). The adjusted hazard ratio of death for PCI was 0.52 at 1 month (95% CI 0.29-0.94) and 0.52 at 3 months (95% CI 0.31-0.85), and the adjusted odds of disability in patients with PCI was 0.53 at 1 year (95% CI 0.35-0.81). CONCLUSIONS: In our cohort, patients with PCI have a lower risk of death at 1- and 3-month FU and a lower proportion of disability at 1-year FU, which needs to be verified by future studies.

Intra-arterial thrombolysis using rt-PA in patients with acute stroke due to vessel occlusion of anterior and/or posterior cerebral circulation.

INTRODUCTION: The aim of our study was to evaluate the safety and efficacy of intra-arterial (IA) thrombolysis using recombinant tissue plasminogen activator (rt-PA) in patients with acute stroke due to occlusion in the anterior or posterior circulation. METHODS: We retrospectively analyzed the clinical and radiological data of 88 consecutive patients with acute ischemic stroke who underwent emergency cerebral angiography for the purpose of subsequent IA thrombolysis. The neurological deficit on admission and discharge was graded using the National Institutes of Health Stroke Scale (NIHSS) score. Baseline computer tomography (CT) scans were examined for any signs indicative of cerebral ischemia. The angiographic findings were classified according to the Thrombolysis in Myocardial Infarction (TIMI) score for myocardial infarction. Follow-up CT scans were examined for hemorrhagic complication. RESULTS: Of the 88 patients who underwent IA thrombolysis, 63 presented with complete or partial arterial occlusion in the suspected perfusion area. In these 63 patients, the median NIHSS score dropped from 15 points on admission to 10 points at discharge. The recanalization rate was 52.6% for partial and complete reperfusion. In-hospital mortality was 20.6% (9.1% for carotid, 44.4% for basilar territory occlusion). Intracerebral bleeding (ICB) occurred in 38.6% of the patients with occlusion in the anterior circulation, resulting in these patients presenting a worse clinical outcome than those without ICB. Only minor extracranial bleedings occurred in 20.6% of patients. Patients with ICB had a significantly higher frequency of ischemic signs on the baseline CT scan. CONCLUSION: Occlusion of a cerebral artery is present in about 75% of the patients eligible for thrombolytic therapy. Intra-arterial thrombolysis using rt-PA in patients with acute ischemic stroke can achieve re-vascularization, although ICB remains the major risk factor affecting its efficacy.

Basilar artery occlusive disease in the New England Medical Center Posterior Circulation Registry.

BACKGROUND: Most reports on basilar artery (BA) occlusive disease have retrospectively described single cases or small patient series. OBJECTIVE: To assess clinical and vascular features, stroke mechanisms, etiologies, and outcome of moderate to severe BA occlusive disease among 407 patients in the New England Medical Center Posterior Circulation Registry, the largest prospective series of consecutively collected patients with posterior circulation ischemia to date. RESULTS: We studied 87 patients and identified 3 patient groups with distinct vascular, clinical, etiological, and prognostic characteristics: isolated BA disease (39 patients [44.8%]), BA involvement as part of widespread posterior circulation atherosclerosis (36 patients [41.4%]), and embolism to the BA (12 patients [13.8%]). Vascular risk factors were common and often multiple. Most patients (54 [62.1%]) had involvement of the midportion of the BA. Fifty-eight patients (66%) initially had transient ischemic attacks, of whom 34 (58.6%) progressed to stroke. Transient ischemic attacks were usually multiple, lasted for several months, and increased in frequency as the stroke approached. When an infarct was present, the middle posterior intracranial territory was most often involved (66 patients [75.9%]). Outcome was much better than previously assumed. The mortality rate was 2.3%, and 62 patients (almost 75%) had minor or no deficits at follow-up. Outcome was best among patients with widespread atherosclerotic disease and worst in 7; (58.3%, with major disability) of 12 patients with embolism to the BA. Distal territory involvement, embolism, BA occlusion, decreased level of consciousness, tetraparesis, and abnormal pupils were significant predictors of poor outcome. CONCLUSION: Inclusion of patients into 1 of the BA groups and early identification of predictive outcome factors guide diagnostic evaluation and treatment.

[Ischemic insult in the anterior and posterior cerebral circulation]. / Ishemicki inzulti prednje i straznje cerebralne cirkulacije.

In the everyday practice among clinical and etiological classifications for ischemic stroke, the terms strokes in the anterior and posterior cerebral circulation are also in use. The aim of this study was to analyze the frequency of ischemic strokes in the anterior and posterior circulation, their age and sex distribution, risk factors and hospital mortality. In the study it was analyzed 1772 patients with acute ischemic stroke hospitalized at the Department of Neurology Tuzla, Bosnia and Herzegovina, between January 1st 1996 and December 31st 2000. The mean age was 65.5 years (+9.9), 942 (55%) were females. Ischemic strokes for all patients were confirmed with computed tomography, while other data were collected from the standard patients' history charts. Anterior circulation stroke (ACS) had 1408 patients (81.8%), the rest of 314 (18.2%) had posterior circulation stroke (PCS). In the both types females were slightly overrepresented: 784 (56%) in ACS, and 158 (50.5%) in PCS. Moreover, females were significantly older than males: 67 (+9.8) versus 64 (+10) years in ACS (p < 0.001), 67.5 (+10.3) versus 63.5 (+9.2) in PCS (p < 0.001). Hypertension was the major risk factor occurring in 67% patients with ACS and 71 with PCS; heart diseases 54% in the both types, and diabetes in 23% patients with ACS and 20% with PCS. The cortical ischemic lesion was verified in 46% patients with ACS, 41% with PCS; subcortical in 12.5% and 14.5%; and lacunar in 41.5% and 44.5%, respectively. Hospital mortality was 30% (430 patients) for ACS, and 32% (101 patients) for PCS. Hospital mortality was considerably higher among females: 33% versus 28% for ACS (p = 0.03), 38% versus 27% for PCS (p = 0.03). On the basis of our study we can conclude that ischemic strokes in the anterior cerebral circulation are 4/5 of all ischemic strokes at the Department of Neurology Tuzla. Both, anterior and posterior circulation strokes are more frequent in females, witches were in average older than males. The cortical lesion dominated in ACS, and lacunar in PCS. The distribution of risk factors (hypertension, heart diseases, and diabetes) is similar for ACS and PCS, and hospital mortality also; however, mortality rate is higher in females.