***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE To investigate the significance of N-terminal proBrain natriuretic peptide ( NT-proBNP ) in predicting the outcome of acute stroke in relation to other cardiovascular variables and stroke severity . DESIGN Prospect i ve study of previously independent acute ischemic and hemorrhagic stroke patients admitted to the acute stroke ward . METHODS Measurements of NT-proBNP in acute phase in addition to st and ard assessment of cardiovascular and neurological details . MAIN OUTCOME MEASURES Concentrations and significance of NT-proBNP  in patients who were dead versus alive at 120 days after acute stroke and  Cox regression analysis with stroke severity measured as  Sc  and inavian Stroke Scale  ( SSS ) and other cardiovascular disease to predict mortality . RESULTS One hundred fourteen patients were recruited , median age 74 years . At 120 days , 13 patients had died . Deceased patients had a significantly higher concentration of NT-proBNP as compared to alive patients ( P < .001 ) . All patients who had died had NT-proBNP concentration above the median for the whole group . Cox regression analysis revealed that NT-proBNP was the most significant independent variable predicting mortality ( odds ratio [ OR ] 2.4 , 95 % confidence interval [ CI ] 1.35 to 4.41 , P = .003 ) followed by the SSS ( OR 0.95 , 95 % CI 0.90 to 0.98 , P = .005 ) . Higher NT-proBNP and lower SSS predicted mortality . There was a significant negative correlation of NT-proBNP with SSS score ( r = -0.24 , P = .02 ) . There were no significant difference in NT-proBNP concentrations between ischemic and hemorrhagic strokes ( P < .346 ) . At 6 weeks , the dependent patients had higher concentrations of NT-proBNP than independent patients . CONCLUSION NT-proBNP , an index of cardiac impairment , has an independent prognostic value in acute stroke patients over other cardiovascular variables and stroke severity . This may provide a channel for interventional therapy in acute stroke Background and Purpose — Because there is no biologic marker offering precise information about stroke etiology , many patients receive a diagnosis of undetermined stroke even after all available diagnostic tests are done , precluding correct treatment . Methods — To examine the diagnostic value of a panel of biochemical markers to differentiate stroke etiologies , consecutive acute stroke patients were prospect ively evaluated .  Brain computed tomography , ultrasonography , cardiac evaluations , and other tests were done to identify an etiologic diagnosis according to TOAST classification . Blood sample s were drawn on Emergency Department arrival ( < 24 hours ) to test selected biomarkers : C-reactive protein , D-dimer , soluble receptor for advanced glycation end products , matrix metalloproteinase-9 , S-100b , brain natriuretic peptide ( BNP ) , neurotrophin-3 , caspase-3 , chimerin , and secretagogin ( assayed by ELISA ) . Results — Of 707 ischemic stroke patients included , 36.6 % were cardioembolic , 21.4 % atherothrombotic , 18.1 % lacunar , and 23.9 % of undetermined origin . High levels of BNP , soluble receptor for advanced glycation end products , and D-dimer ( P<0.0001 ) were observed in patients with cardioembolic stroke . Independent predictors ( odds ratios with CIs are given ) of cardioembolic stroke were as follows : atrial fibrillation 15.3 ( 8.4–27.7 , P<0.001 ) ; other embolic cardiopathies 14.7 ( 4.7–46 , P<0.001 ) ; total anterior circulation infa rct ion 4 ( 2.3–6.8 , P<0.001 ) ; BNP > 76 pg/mL 2.3 ( 1.4–3.7 , P=0.001 ) ; and D-dimer > 0.96 & mgr;g/mL 2.2 ( 1.4–3.7 , P=0.001 ) . Even among patients with transient symptoms ( n=155 ) , a high BNP level identified cardioembolic etiology ( 6.7 , 2.4–18.9 ; P<0.001 ) . A model combining clinical and biochemical data had a sensitivity of 66.5 % and a specificity of 91.3 % for predicting cardioembolism . Conclusions — Using a combination of biomarkers may be a feasible strategy to improve the diagnosis of cardioembolic stroke in the acute phase , thus rapidly guiding other diagnostic tests and accelerating the start of optimal secondary prevention OBJECTIVE To determine the value of the use of plasma B-type natriuretic peptide ( BNP ) among acute ischemic stroke patients in a Chinese emergency department ( ED ) . MATERIAL S AND METHODS In our ED , the emergency physicians prospect ively assessed consecutive adult patients with acute phase of ischemic stroke and measured plasma BNP by Biosite Triage( ® )BNP POCT platform on admission , then followed up these patients . And the stroke neurologists evaluated patients ' functional outcome at hospital discharge , and also made discharge diagnosis and stroke etiologic subtypes according to TOAST criteria : large-artery atherosclerosis ( LAA ) , cardioembolism ( CE ) , small-artery occlusion ( SAO ) , stroke of other determined etiology ( SOE ) and stroke of other undetermined etiology ( SUE ) . RESULTS In this study , 142 of 238 acute ischemic stroke patients met the study criteria [ mean age 70.84 ± 11.48 years , 74 ( 52.11 % ) female ] . Of the 142 patients , 35.92 % were diagnosed with LAA at discharge , 25.35 % with CE , 27.46 % with SAO , 11.27 % with SOE or SUE . Age , previous cardiac disease , atrial fibrillation , the length of hospital stays , SSS score on admission ≤ 25 and mRS ≥ 3 or death at discharge were all significantly higher in the CE patients compared to other subtypes ( p<0.01 ) . And the mean BNP concentration was significantly higher in the CE group than in other three subtypes ( p<0.001 ) . The optimal cut-off concentration , sensitivity and specificity of the plasma BNP concentration suitable to distinguish CE from non-CE were 66.50 pg/ml , 75.0 % and 88.7 % , respectively . CONCLUSIONS Plasma BNP level is significantly higher in CE patients than in other TOAST subtypes , and by using Biosite Triage( ® )BNP POCT platform , emergency physicians should strongly consider CE subtype with the plasma BNP level of over 66.50 pg/ml . However , the single BNP biomarker panel can not be used to confidently rule out or identify stroke subtypes as a diagnosis and must be taken in context with clinical assessment and judgment before making management decisions in the ED Background and Purpose — A new clinical construct termed embolic stroke of undetermined source ( ESUS ) was recently introduced , but no such population has been described yet . Our aim is to provide a detailed descriptive analysis of an ESUS population derived from a large prospect i ve ischemic stroke registry using the proposed diagnostic criteria . Methods — The criteria proposed by the Cryptogenic Stroke/ESUS International Working Group were applied to the Athens Stroke Registry to identify all ESUS patients . ESUS was defined as a radiologically confirmed nonlacunar brain infa rct in the absence of ( a ) extracranial or intracranial atherosclerosis causing ≥50 % luminal stenosis in arteries supplying the ischemic area , ( b ) major-risk cardioembolic source , and ( c ) any other specific cause of stroke . Results — Among 2735 patients admitted between 1992 and 2011 , 275 ( 10.0 % ) were classified as ESUS . In the majority of ESUS ( 74.2 % ) , symptoms were maximal at onset . ESUS were of moderate severity ( median National Institute Health Stroke Scale score , 5 ) . The most prevalent risk factor was arterial hypertension ( 64.7 % ) , and 50.9 % of patients were dyslipidemic . Among potential causes of the ESUS , covert atrial fibrillation ( AF ) was the most prevalent : in 30 ( 10.9 % ) patients , AF was diagnosed during hospitalization for stroke recurrence , whereas in 50 ( 18.2 % ) patients AF was detected after repeated ECG monitoring during follow-up . Also , covert AF was strongly suggested in 38 patients ( 13.8 % ) but never recorded . Conclusions — About 10 % of patients with first-ever ischemic stroke met criteria for ESUS ; covert paroxysmal AF seems to be a frequent cause of ESUS Background and Purpose The etiology of ischemic stroke affects prognosis , outcome , and management . Trials of therapies for patients with acute stroke should include measurements of responses as influenced by subtype of ischemic stroke . A system for categorization of subtypes of ischemic stroke mainly based on etiology has been developed for the Trial of Org 10172 in Acute Stroke Treatment ( TOAST ) . Methods A classification of subtypes was prepared using clinical features and the results of ancillary diagnostic studies . “ Possible ” and “ probable ” diagnoses can be made based on the physician 's certainty of diagnosis . The usefulness and interrater agreement of the classification were tested by two neurologists who had not participated in the writing of the criteria . The neurologists independently used the TOAST classification system in their bedside evaluation of 20 patients , first based only on clinical features and then after review ing the results of diagnostic tests . Results The TOAST classification denotes five subtypes of ischemic stroke : 1 ) large-artery atherosclerosis , 2 ) cardioembolism , 3 ) small-vessel occlusion , 4 ) stroke of other determined etiology , and 5 ) stroke of undetermined etiology . Using this rating system , interphysician agreement was very high . The two physicians disagreed in only one patient . They were both able to reach a specific etiologic diagnosis in 11 patients , whereas the cause of stroke was not determined in nine . Conclusions The TOAST stroke subtype classification system is easy to use and has good interobserver agreement . This system should allow investigators to report responses to treatment among important subgroups of patients with ischemic stroke . Clinical trials testing treatments for acute ischemic stroke should include similar methods to diagnose subtypes of stroke Background and Purpose : Our previous retrospective study demonstrated that a brain natriuretic peptide ( BNP ) level of > 140 pg/ml on admission was useful to distinguish cardioembolism ( CE ) from non-CE . The aim of the present study was to prospect ively investigate the utility of this predefined threshold . Method : Two hundred and twenty-one consecutive patients were prospect ively enrolled . On admission , the  BNP levels of the patients were measured and classified according to low BNP ( ≤140.0 pg/ml ) or high BNP ( > 140.0 pg/ml ) levels . Final diagnosis of stroke subtype on discharge was made using the TOAST criteria . Measured parameters included the sensitivity , specificity , positive predictive value , and negative predictive value for CE in the high BNP group . Results : There were 81 patients in the high BNP group and 140 patients in the low BNP group . A total of 76 ( 34.4 % ) patients were diagnosed with CE , including 59 ( 72.8 % ) patients in the high BNP group and 17 ( 12.1 % ) patients in the low BNP group ( p < 0.001 ) . A BNP level > 140.0 pg/ml corresponded to a sensitivity of 77.6 % , specificity of 84.8 % , positive predictive value of 72.8 % , and negative predictive value of 87.9 % for a diagnosis of CE . Conclusion : A BNP level of > 140.0 pg/ml on admission in patients with acute ischemic stroke is a strong biochemical predictor for CE Objective : Antiplatelets are recommended for secondary prevention in patients with cryptogenic stroke ; however , some patients may present with a cardioembolic source that has not been detected , which may modify the treatment . Because high pro – brain natriuretic peptide ( BNP ) levels are associated with cardioembolic stroke , our objective was to determine whether pro-BNP levels in the acute phase of stroke predict the development of atrial fibrillation ( AF ) in patients with cryptogenic stroke . Methods : A prospect i ve study including patients with cryptogenic stroke was conducted . Demographic data , medical history , and stroke characteristics were assessed at admission . A blood sample was obtained within the first 24 hours from stroke onset to determine pro-BNP levels . Patients were followed by a neurologist at 3 and 6 months and later by a primary care physician for 2 years to evaluate the development of AF .  Results : One thous and fifty patients with ischemic stroke were evaluated . Three hundred seventy-two patients ( 35 % ) had cryptogenic stroke . One hundred eight patients were excluded from the study , so 264 patients were valid for the analysis .  AF was detected in 15 patients ( 5.6 % ) during the follow-up . Patients who developed AF were older , had hypertension more frequently , and showed higher levels of pro-BNP . In the logistic regression model , we found that pro-BNP ≥360 pg/mL was the only variable independently associated with the risk of developing AF ( odd 
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Both peptides also increased significantly the area under the curve and integrated discrimination improvement index compared with clinical models .
Natriuretic peptides are strongly increased in cardioembolic strokes .