Brain natriuretic peptide as a predictor of delayed atrial fibrillation after ischaemic stroke and transient ischaemic attack

Collateral Circulation and BNP in Predicting Outcome of Acute Ischemic Stroke Patients with Atherosclerotic versus Cardioembolic Cerebral Large-Vessel Occlusion Who Underwent Endovascular Treatment

PURPOSE

The aim of this study was to verify the value of collateral circulation and B-type natriuretic peptide (BNP) in predicting clinical outcomes of patients with acute ischemic stroke (AIS) and their biomarker value for stroke subtypes before endovascular treatment (EVT).

PATIENTS AND METHODS

In this retrospective study, 182 patients who underwent EVT for unilateral anterior circulation large-vessel occlusion between March 2016 and January 2022 were analyzed. The modified collateral circulation scoring system on four-dimensional computed tomography angiography (4D CTA-CS) was used to assess collateral status, and stroke subtypes were determined according to the TOAST classification criteria. Patients were divided into good (mRS ≤ 2) and poor outcome (mRS > 2) groups based on their modified Rankin Scale (mRS) score at 3 months.

RESULTS

4D CTA-CS was an independent predictor of the clinical outcome for all AIS patients (odds ratio = 0.253; 95% CI, 0.147-0.437; p < 0.001), CE stroke patients (odds ratio = 0.513; 95% CI, 0.280-0.939; p = 0.030), and LAA stroke patients (odds ratio = 0.148; 95% CI, 0.049-0.447; p = 0.001). The BNP was a biomarker for clinical outcome prediction in CE (odds ratio = 1.004; 95% CI, 1.001-1.008; p = 0.005) but not in LAA patients. Combined with BNP, 4D CTA-CS improved predictive values for clinical outcomes (p < 0.05).

CONCLUSION

Collateral status and BNP could be used as independent predictors of clinical outcomes in AIS patients and could determine stroke subtypes (CE stroke or LAA stroke). In addition, the model of 4D CTA-CS combined with BNP was the most effective in predicting clinical outcomes compared with collateral status or BNP alone.

Molecular biomarkers predicting newly detected atrial fibrillation after ischaemic stroke or TIA: A systematic review

Background:

Several molecular biomarkers are available that predict newly detected atrial fibrillation (NDAF). We aimed to identify such biomarkers that predict NDAF after an Ischaemic stroke (IS)/Transient Ischaemic Attack (TIA) and evaluate their performance.

Methods:

A systematic review was undertaken in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies of patients with IS, TIA, or both, who underwent ECG monitoring for ⩾24 h, which reported molecular biomarkers and frequency of NDAF after electronic searches of multiple databases were included.

Results:

Twenty-one studies (76% IS, 24% IS and TIA) involving 4640 patients were included. Twelve biomarkers were identified, with cardiac biomarkers evaluated in the majority (75%) of patients. Performance measures were inconsistently reported. Among cohorts selecting high-risk individuals (12 studies), the most studied biomarkers were N-Terminal-Pro Brain Natriuretic Peptide (NT-ProBNP, five studies; C-statistics reported by three studies, 0.69–0.88) and Brain Natriuretic Peptide (BNP, two studies; C-statistics reported in two studies, 0.68–0.77). Among unselected cohorts (nine studies), the most studied biomarker was BNP (six studies; C-statistics reported in five studies, 0.75–0.88). Only BNP was externally validated (two studies) but using different thresholds to categorise risk of NDAF.

Conclusion:

Cardiac biomarkers appear to have modest to good discrimination for predicting NDAF, although most analyses were limited by small, heterogeneous study populations. Their clinical utility should be explored further, and this review supports the need to assess the role of molecular biomarkers in large prospective studies with standardised selection criteria, definition of clinically significant NDAF and laboratory assays.

Blood biomarkers to detect new-onset atrial fibrillation and cardioembolism in ischemic stroke patients

BACKGROUND

Accumulating data suggest blood biomarkers could inform stroke etiology.

OBJECTIVE

The purpose of this study was to investigate the performance of multiple blood biomarkers in elucidating stroke etiology with a focus on new-onset atrial fibrillation (AF) and cardioembolism.

METHODS

Between January and December 2017, information on clinical and laboratory parameters and stroke characteristics was prospectively collected from ischemic stroke patients recruited from the National University Hospital, Singapore. Multiple blood biomarkers (N-terminal pro-brain natriuretic peptide [NT-proBNP], d-dimer, S100β, neuron-specific enolase, vitamin D, cortisol, interleukin-6, insulin, uric acid, and albumin) were measured in plasma. These variables were compared with stroke etiology and the risk of new-onset AF and cardioembolism using multivariable regression methods.

RESULTS

Of the 515 ischemic stroke patients (mean age 61 years; 71% men), 44 (8.5%) were diagnosed with new-onset AF, and 75 (14.5%) had cardioembolism. The combination of 2 laboratory parameters (total cholesterol ≤169 mg/dL; triglycerides ≤44.5 mg/dL) and 3 biomarkers (NT-proBNP ≥294 pg/mL; S100β ≥64 pg/mL; cortisol ≥471 nmol/l) identified patients with new-onset AF (negative predictive value [NPV] 90%; positive predictive value [PPV] 73%; area under curve [AUC] 85%). The combination of 2 laboratory parameters (total cholesterol ≤169 mg/dL; triglycerides ≤44.5 mg/dL) and 2 biomarkers (NT-proBNP ≥507 pg/mL; S100β ≥65 pg/mL) identified those with cardioembolism (NPV 86%; PPV 78%; AUC 87%). Adding clinical predictors did not improve the performance of these models.

CONCLUSION

Blood biomarkers could identify patients with increased likelihood of cardioembolism and direct the search for occult AF.

Paroxysmal Atrial Fibrillation in Cryptogenic Stroke Patients With Major-Vessel Occlusion

Background and Purpose: To determine whether acute major-vessel occlusion (MVO) predicts atrial fibrillation (AF) in cryptogenic stroke (CS) patients, we analyzed the association between acute MVO and AF detected by insertable cardiac monitoring (ICM).

Methods: We conducted a retrospective, multicenter, observational study of patients with CS who underwent ICM implantation between October 2016 and March 2018. In this analysis, we included follow-up data until June 2018. We analyzed the association of MVO with AF detected by ICM.

Results: We included 84 consecutive patients with CS who underwent ICM implantation. The proportion of patients with newly detected AF by ICM was higher in patients with MVO than in those without (41% [12/29] vs. 13% [7/55], p < 0.01) within 90 days of ICM implantation. The MVO was associated with AF after adjustment for each clinically relevant factor.

Conclusions: MVO was independently associated with AF detection in patients with CS, which suggests that MVO may be a useful predictor of latent AF. It is therefore essential to actively assess latent AF in patients with CS presenting with MVO.

Brain Natriuretic Peptide and Discovery of Atrial Fibrillation After Stroke

Background and Purpose—

Diagnosing paroxysmal atrial fibrillation (pAF) can be challenging after acute ischemic stroke. Enhanced and prolonged Holter-ECG monitoring (EPM) improves the detection rate but is not feasible for all patients. We hypothesized that brain natriuretic peptide (BNP) may help to identify patients with stroke at high risk for pAF to select patients for EPM more effectively.

Methods—

Patients with acute cerebral ischemia ≥60 years presenting in sinus rhythm and without history of AF were included into a prospective, randomized multicenter study to receive either EPM (3× 10-day Holter-ECG) or usual stroke care diagnostic work-up. BNP plasma levels were measured on randomization and 3 months thereafter. Levels were compared between patients with and without pAF detected by means of EPM or usual care. Furthermore, the number needed to screen for EPM depending on BNP cut offs was calculated.

Results—

A total of 398 patients were analyzed. In 373 patients (93.7%), BNP was measured at baseline and in 275 patients (69.1%) after 3 months. pAF was found in 27 patients by means of EPM and in 9 patients by means of usual care ( P =0.002). Median BNP was higher in patients with pAF as compared to patients without AF in both study arms at baseline (57.8 versus 28.3 pg/mL in the EPM arm, P =0.0003; 46.2 versus 27.7 pg/mL, P =0.28 in the control arm) and after 3 months (74.9 versus 31.3 pg/mL, P =0.012 in the EPM arm, 99.3 versus 26.3 pg/mL, P =0.02 in the control arm). Applying a cut off of 100 pg/mL, the number needed to screen was reduced from 18 by usual care to 3 by EPM.

Conclusions—

BNP measured early after ischemic stroke identifies a subgroup of patients with stroke at increased risk for AF, in whom EPM is particularly efficacious.

Registration—

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01855035.

Accurate etiology diagnosis in patients with stroke and atrial fibrillation: A role for brain natriuretic peptide

BACKGROUND

Atrial fibrillation (AF) is the leading cause of cardioembolic stroke (CES), and patients with stroke and AF are frequently assumed to have CES. However, strokes presumably due to atherosclerotic pathophysiologies in large or small vessels can also occur in patients with AF. The aims of the present study were to clarify the prevalence of and factors related to a non-cardioembolic etiology in acute stroke patients with AF.

METHODS

From March 2011 through May 2017, consecutive acute ischemic stroke patients with AF were retrospectively recruited. The concomitant presence of non-cardioembolic features (small vessel occlusion [SVO] or large artery atherosclerosis [LAA]) on imaging was evaluated. The frequency of and factors associated with co-existing SVO/LAA features were assessed.

RESULTS

A total of 560 consecutive patients with AF and acute stroke (237 women; median age 78 [IQR 71-85] years; NIHSS score 9 [3-20]) were enrolled. Of these, 42 (7.5%) had co-existing SVO/LAA features. Multivariable logistic regression analysis showed that the brain natriuretic peptide level (BNP, OR 0.78, p = .030 per 100 pg/mL increase) was independently and negatively associated with co-existing SVO/LAA features and receiver operating characteristic curve analysis revealed the practical cut-off BNP value was 130 pg/mL (sensitivity 54% and specificity 68%).

CONCLUSION

SVO/LAA features were found in 7.5% of acute stroke patients with AF. A relatively low BNP level on admission was independently associated with co-existing SVO/LAA features. Thorough examination for a more appropriate etiology may be particularly necessary in acute stroke patients with AF and a relatively low BNP level.

Can Admission BNP Level Predict Outcome After Intravenous Thrombolysis in Acute Ischemic Stroke?

OBJECTIVE

Our study aimed to determine the prognostic value of elevated Brain Natriuretic Peptide (BNP) among patients who received intravenous thrombolysis (IVT) in acute ischemic stroke (AIS).

BACKGROUND

The elevation in BNP level is correlated with infarct size, poststroke mortality, and CHADS2 score. Currently, there is a lack of validated biomarker to predict the outcome in patients with acute ischemic stroke, and there is a complex interaction amongst multiple variables.

DESIGN/METHODS

A retrospective review of medical records of patients admitted to our institution with acute ischemic stroke was performed. The patients who received intravenous thrombolysis were selected for analysis and divided into 2 groups based on the level of BNP. We compared the baseline demographics, past medical history, stroke etiology, discharge disposition, and 3-month mRS between both groups. Multivariate logistic regression analysis was performed to identify the predictors of poor outcome following intravenous thrombolysis in acute ischemic stroke.

RESULTS

A total of 90 patients were recruited in the study; 53 patients were found to have an elevated BNP (high BNP was defined as >100 pg/mL) level, whereas 37 had low BNP levels. Our study showed that patients with elevated BNP were more likely to have an elevation in admission and discharge NIHSS, serum creatinine, left atrial size, and blood glucose (P<0.05). Atrial fibrillation and cardioembolic strokes were seen most often in the population with elevated BNP (P<0.05). The patients with elevated BNP were less likely to be discharged home, and 3-month mRS was found to be higher, but these were not significant. On multivariate analysis, elevated BNP was not found to be an independent factor for poor outcome.

CONCLUSIONS

Elevated BNP level was not found to be an independent marker of poor outcome in AIS patients following IVT.

A new algorithm for suspected stroke patient management with NT-proBNP POCT platform in the emergency department: A new algorithm for suspected stroke patient

Introduction:

Stroke is a leading cause of mortality and morbidity in China. Of the different subtypes of ischemic stroke, cardioembolic stroke is of particular importance because it is potentially preventable. This study aimed to evaluate the usefulness of measuring N-terminal pro-brain natriuretic peptide in the emergency department in early recognition of patients with cardioembolic stroke.

Methods:

This was a multicenter prospective cohort study conducted from 1 June 2015 to 30 June 2016 in four emergency departments. Adult patients with acute ischemic stroke were recruited. Plasma N-terminal pro-brain natriuretic peptide was measured in the emergency department. Discharge diagnosis was determined by neurologists according to the Trial of ORG 10172 in Acute Stroke Treatment criteria. The diagnostic performance of N-terminal pro-brain natriuretic peptide was assessed by measuring the sensitivity, specificity, receiver operating characteristic curve, and the area under curve.

Results:

In all, 258 patients were analyzed. Of them, 17.9% were diagnosed with cardioembolic stroke. The optimal cut-off concentration, sensitivity, specificity, and the area under the curve of the plasma N-terminal pro-brain natriuretic peptide concentration suitable to distinguish cardioembolic stroke from other subtypes of stroke were 501.2 pg/mL, 82.6%, 80.2%, and 0.87 (95% confidence interval: 0.83–0.92), respectively.

Conclusion:

Emergency physicians should strongly consider cardioembolic stroke in patients presented with acute ischemic stroke with an N-terminal pro-brain natriuretic peptide level over 501.2 pg/mL. However, it must be considered in context with clinical assessment and judgment before making treatment decisions.

N-terminal pro B-type natriuretic peptide in systematic screening for atrial fibrillation

OBJECTIVE

Screening for atrial fibrillation (AF) in individuals aged 65 and above is recommended by the European Society of Cardiology. Increased levels of the biomarker N-terminal pro B-type natriuretic peptide (NT-proBNP) has in cohort studies been associated with incident AF.The aim of this study was to assess whether NT-proBNP could be useful for AF detection in systematic screening.

METHODS

The Strokestop study entailed 7173 Swedish residents aged 75/76 that were screened for AF using twice daily intermittent ECG recordings during 2 weeks. In a substudy of 886 participants, the last 815 consecutive participants and 71 individuals with newly detected AF, levels of NT-proBNP were determined.

RESULTS

Participants with newly detected AF (n=96) had a median NT-proBNP of 330 ng/L (IQR 121;634). In individuals without AF (n=742), median NT-proBNP was 171 ng/L (IQR 95;283), p<0.001. The CHA₂DS₂-VASc parameters did not differ significantly between individuals with newly detected AF and without AF nor between newly detected AF in the NT-proBNP cohort compared with the cohort where NT-proBNP was not assessed. Using an NT-proBNP cut-off of ≥125 ng/L in a non-acute setting yielded a negative predictive value of 92%, meaning that 35% fewer participants would need to be screened when applied to systematic AF screening. Adding weight to NT-proBNP further reduced participants needed to be screened with a preserved sensitivity.

CONCLUSIONS

NT-proBNP was increased in individuals with newly detected AF. Prospective studies could clarify if NT-proBNP can be used to correctly select individuals that benefit most from AF screening.

CLINICAL TRIALS

ClinicalTrials.gov. Identifier: NCT01593553.

Impact of BNP on cryptogenic stroke without potential embolic sources on transesophageal echocardiography

BACKGROUND

Clinical characteristics are important for determining the etiologies of embolic stroke, including patent foramen ovale and complex aortic plaques demonstrated on transesophageal echocardiography (TEE). This study sought to analyze the clinical signs of cryptogenic stroke (CS) without such embolic etiologies and to examine the association between CS and brain natriuretic peptide (BNP), which is currently unknown.

METHODS

Patients with CS after routine examinations who underwent TEE were included in this single-center observational study. Patients were classified into the potential embolic sources (PES) group (patients having PES on TEE) and the no potential embolic source (NPES) group. Patients were also categorized according to the tertile of BNP.

RESULTS

A total of 158 patients (age, 64.0 ± 13.9 years; 119 males) with CS were enrolled. The PES group had 108 (68%) patients, and the NPES group had 50 (32%). Hypertension was more common, and glucose, D-dimer, and BNP were higher in the NPES than in the PES group (p<0.05). NPES was independently associated with high-BNP tertile (OR: 5.61; 95% CI: 1.91 to 16.44; p=0.002).

CONCLUSIONS

BNP, an indicator of cardioembolism, was closely associated with NPES. Cardiogenic mechanisms may be implicated in the etiology of CS without potential embolic etiologies on TEE.

Validation of the use of B-type natriuretic peptide point-of-care test platform in preliminary recognition of cardioembolic stroke patients in the ED

AIM

The aim of the study is to validate of the use of plasma B-type natriuretic peptide (BNP) point-of-care test platform in preliminary recognition of cardioembolic stroke patients in the emergency department (ED).

METHODS

In our ED, emergency physicians prospectively assessed consecutive adult patients with acute phase of ischemic stroke and measured plasma BNP by point-of-care test platform on admission. The included patients with plasma BNP concentration more than 66.50 pg/mL were presumed to be classified as the cardioembolism (CE) subtype and were then followed up. Stroke neurologists evaluated patients' functional outcome at hospital discharge and also made discharge diagnosis and stroke etiologic subtypes according to Trial of ORG 10172 in Acute Stroke Treatment criteria: large artery atherosclerosis, CE, small artery occlusion, stroke of other determined etiology, and stroke of other undetermined etiology.

RESULTS

In this study, 172 of 262 acute ischemic stroke patients met the study criteria (mean age, 71.18 ± 11.65 years; 53.49% female). Of the 172 patients, 38.95% were diagnosed with large artery atherosclerosis at discharge; 26.16%, with CE; 24.42%, with small artery occlusion; and 10.47%, with stroke of other determined etiology or stroke of other undetermined etiology. Age, previous cardiac disease, atrial fibrillation, length of hospital stays, Scandinavian Stroke Scale score on admission less than or equal to 25, and modified Rankin Scale greater than or equal to 3 or death at discharge were all significantly higher in the CE patients compared to other subtypes (P < .01). The mean BNP concentration was significantly higher in the CE group than in other 3 subtypes (P < .01). The plasma BNP level greater than 66.50 pg/mL had good corresponding diagnostic performance in preliminary recognition of cardioembolic stroke patients (sensitivity, 75.56%; specificity, 87.40%).

CONCLUSIONS

In this study, we found that the plasma BNP level greater than 66.50 pg/mL as a reference index had good corresponding diagnostic performance in preliminary recognition of cardioembolic stroke patients. However, the single BNP biomarker panel cannot be used to confidently identify CE subtype as a diagnosis and must be taken in context with clinical assessment and judgment before making management decisions.

Troponin-I is a predictor of a delayed diagnosis of atrial fibrillation in acute ischemic stroke and transient ischemic attack

BACKGROUND

Prolonged cardiac monitoring detects higher rates of atrial fibrillation (AF) in ischemic stroke and transient ischemic attack (TIA) but is costly and has practical implications. The use of admission troponin-I (TnI) level to identify patients at high risk of delayed AF detection was investigated.

METHODS

Consecutive ischemic stroke and TIA cases presenting to our institute over a 13-month period were identified from the Irish Stroke and TIA Register. Electronic databases and case notes were examined. "Delayed" AF was diagnosed after a sinus rhythm admission electrocardiogram and no documented history. Group comparisons were made by AF status. The association between TnI and AF was investigated using a multivariate regression model.

RESULTS

A total of 185 cases (130 ischemic stroke) were analyzed. Mean age (standard deviation) was 73.3 (13.9) years, 47% female. Sixty-two cases (33.5%) had AF. The first documented presentation of AF was found in 21 cases, on admission electrocardiogram (n = 11) or inpatient telemetry (delayed, n = 10). TnI was higher in those with delayed AF than in those without AF (W = 194; P = .036). A higher proportion of those with an elevated TnI (30%) than those with a normal TnI (6.1%) had delayed diagnosis of AF (χ(2) = 6.41, P = .011). Having an abnormal TnI was a significant independent predictor of delayed AF detection (odds ratio, 5.8; P = .037).

CONCLUSIONS

TnI elevation is associated with a higher likelihood of subsequent AF diagnosis. Identification of these higher risk stroke and TIA cases for more intensive cardiac monitoring may improve stroke secondary prevention practices.

Plasma brain natriuretic Peptide as a predictive marker of early recurrent stroke in cardioembolic stroke patients

BACKGROUND

Whether brain natriuretic peptide (BNP) levels are associated with early recurrent stroke in cardioembolic stroke patients was investigated.

METHODS

From January 2010 to March 2014, consecutive patients within 24 hours of onset of cardioembolic stroke were prospectively enrolled, and admission plasma BNP levels were measured. Recurrent stroke was identified as the occurrence of additional neurologic deficits and the appearance of a new infarct on neuroimaging. Patients were divided into 2 groups: the recurrence group and the nonrecurrence group. Factors associated with stroke recurrence were investigated by multiple logistic regression analysis.

RESULTS

A total of 348 patients were included; 17 patients (5%) had recurrent stroke during hospitalization. The median interval from stroke onset to recurrent stroke was 4 days (range, 0-30). BNP levels were significantly higher in the recurrence group than in the nonrecurrence group (304.1 vs. 206.5 pg/mL, P = .029). The optimal cutoff level, sensitivity, and specificity of BNP levels to distinguish the recurrence group from the nonrecurrence group were 255.0 pg/mL, 76%, and 60%, respectively. On multivariate analysis after adjustment for confounders, plasma BNP ≥ 255.0 pg/mL (odds ratio, 5.21; 95% confidence interval, 1.63-16.72; P = .005) was independently associated with recurrent stroke during hospitalization in cardioembolic stroke patients.

CONCLUSIONS

Plasma BNP could be a useful marker for predicting early recurrent stroke during hospitalization in cardioembolic stroke patients.

Three-Dimensional Analysis of the Left Atrial Appendage for Detecting Paroxysmal Atrial Fibrillation in Acute Ischemic Stroke

Background

Atrial fibrillation impairs left atrial appendage function and the thrombus formation in the left atrial appendage is a major cause of cardioembolic stroke.

Aims

To evaluate the association between the volume of the left atrial appendage measured by real-time three-dimensional transesophageal echocardiography and presence of paroxysmal atrial fibrillation in patients with cerebral infarction or transient ischemic attack.

Methods

Real-time three-dimensional transesophageal echocardiography was performed to measure left atrial appendage end-diastolic and end-systolic volumes to calculate left atrial appendage ejection fraction. Patients with normal sinus rhythm at the time of real-time three-dimensional transesophageal echocardiography were divided into groups with and without paroxysmal atrial fibrillation. Volumetric data were corrected with the body surface area.

Results

Of 146 patients registered, 102 (29 women, 72·2 ± 10·7 years) were normal sinus rhythm at the examination. In 23 patients with paroxysmal atrial fibrillation, left atrial appendage end-diastolic volume (4·78 ± 3·00 ml/m2 vs. 3·14 ± 2·04 ml/m2, P = 0·003) and end-systolic volume (3·10 ± 2·47 ml/m2 vs. 1·39 ± 1·56 ml/m2, P < 0·001) were larger and left atrial appendage ejection fraction (37·3 ±19·1% vs. 57·1 ± 17·5%, P < 0·001) was lower than in the other 79 patients without paroxysmal atrial fibrillation. The optimal cutoff for left atrial appendage peak flow velocity to predict paroxysmal atrial fibrillation was 39·0 cm/s (sensitivity, 54·6%; specificity, 89·7%; c-statistic, 0·762). The cutoffs for left atrial appendage end-diastolic volume, end-systolic volume, and ejection fraction were 4·52 ml/m2 (sensitivity, 47·8%; specificity, 82·3%; c-statistic, 0·694), 1·26 ml/m2 (sensitivity, 91·3%; specificity, 60·3%; c-statistic, 0·806), and 47·9% (sensitivity, 78·3%; specificity, 74·7%; c-statistic, 0·774), respectively. In multivariate analysis, all these parameters were independently associated with paroxysmal atrial fibrillation after adjusting for sex, age, diabetes mellitus, and previous stroke.

Conclusions

Left atrial appendage volumetric analysis by real-time three-dimensional transesophageal echocardiography is a promising method for detecting paroxysmal atrial fibrillation in acute cerebral infarction or transient ischemic attack.

[Cardioembolic stroke associated with atrial fibrillation]

Cardioembolic stroke is approximately 30% of brain infarction, and most of the embolus sources are atrial fibrillation (AF). Brain infarction with AF was associated with an elderly woman, main brain arterial occlusion, and large infarcts. Therefore, patient outcome is so sever, and mortality is very high compared with other stroke types. Use of the anticoagulant before stroke onset is only 32%, and less than 1.6 of PT-INR was 58.4%. The hospitalized recurrence was 7.5%, which was not higher than stroke patients without AF. For detection of the intracardiac tthrombus, transesophageal cardiac-echogram detected thrombus in 16.4%. Within five years after discharge, mortality rate was higher in stroke patients with AF than those without AF. Brain infarction with AF should be knock-out stroke.

Brain natriuretic peptide in acute ischemic stroke

Elevated serum brain natriuretic peptide (BNP) levels are associated with cardioembolic stroke mainly because of atrial fibrillation (AF). However, the mechanisms of increased serum BNP levels are hitherto unclear. We aimed to identify the factors associated with increased BNP levels in patients with acute ischemic stroke. We measured serum BNP levels in consecutive patients aged 18 years or older. Stroke subtypes were classified using the Trial of ORG 10172 in Acute Stroke Treatment criteria. Categorical variables included age, sex, smoking status, alcohol consumption status, hypertension, diabetes mellitus, dyslipidemia, coronary artery disease (CAD), AF, antiplatelet therapy, and anticoagulant therapy. Continuous variables included hemoglobin, creatinine (Cr), β-thromboglobulin, platelet factor 4, thrombin-antithrombin complex, and d-dimer levels. We further determined the relationship between serum BNP and intima-media thickness, left ventricular ejection fraction, size of infarction, National Institutes of Health Stroke Scale score on admission, and modified Rankin Scale (mRS) score at discharge. Of the 231 patients (mean age, 71 ± 12 years) with acute ischemic stroke (AIS), 36% were women. Serum BNP levels significantly correlated with CAD, AF, Cr, mRS, and cardioembolism (CE) (Dunnett method, P = .004). BNP levels were significantly higher in patients with larger infarcts, higher mRS scores, and higher CHADS2 scores. The levels were higher in patients with larger infarcts, higher mRS scores at discharge, and higher CHADS2 scores among AF patients.

Time course of NT-proBNP levels after acute ischemic stroke

BACKGROUND

Studies suggest that N-terminal-pro-brain natriuretic peptide (NT-proBNP) can be a biomarker of cardioembolic stroke. However, the best time to measure it after stroke is unknown. We studied the time course of NT-proBNP in patients with ischemic stroke.

METHODS

Consecutive acute ischemic stroke patients were admitted over 10 months to a Stroke Unit. Stroke type was classified according to TOAST. Blood samples were drawn within 24, 48, and 72 hours after stroke. Friedman test was used to compare NT-proBNP values across the 3 times in all, cardioembolic and non-cardioembolic stroke patients. Post hoc analysis with Wilcoxon signed-rank tests was conducted with a Bonferroni correction. Mann-Whitney test was used to compare median values of NT-proBNP between cardioembolic and non-cardioembolic stroke patients. ROC curves were drawn to determine NT-proBNP accuracy to diagnose cardioembolic stroke at 24, 48, and 72 hours after stroke onset.

RESULTS

One hundred and one patients were included (29 cardioembolic) with a mean age of 64.5±12.3 years. NT-proBNP values for cardioembolic stroke were significantly higher (P < 0.001) than for non-cardioembolic stroke in the 3 time points. NT-proBNP was highest in the first 24-48 h after ischemic stroke and decreased significantly 72 h after stroke onset. The area under the curve for the three time points was similar.

CONCLUSION

NT-proBNP levels were highest in the first 2 days after ischemic stroke and declined significantly thereafter. However, the area under the curve for the three time points was similar. The first 72 hours after ischemic stroke have a similar diagnostic accuracy to diagnose cardioembolic stroke.

Brain natriuretic peptide on admission as a biological marker of long-term mortality in ischemic stroke survivors

BACKGROUND AND PURPOSE

We investigated whether brain natriuretic peptide (BNP) can serve as a biological marker of long-term mortality in ischemic stroke survivors.

METHODS

Consecutive patients with ischemic stroke within 24 h of onset from April 2007 to December 2010 were prospectively enrolled, and admission plasma BNP levels were measured. Survivors were followed up until 1 year after stroke onset. Patients were divided into two groups: the deceased group and the surviving group. The factors associated with long-term mortality were investigated by multiple logistic regression analysis.

RESULTS

A total of 736 patients who were alive at hospital discharge were included; 130 (17.7%) patients died. On multivariate analysis, age>75 years (odds ratio, OR, 2.83; 95% CI, 1.74-4.60, p=0.0001), dialysis-dependent chronic renal failure (OR, 5.99; 95% CI, 2.18-16.47, p=0.0005), modified Rankin Scale score>3 at discharge (OR, 4.41; 95% CI, 2.76-7.05, p<0.0001), and plasma BNP>100.0 pg/ml (OR, 3.94; 95% CI, 2.31-6.73, p<0.0001) were found to be independently associated with long-term mortality. We developed a risk score from 4 variables (each variable: 1 point, total score: 0-4 points). The mortality rates were 2% with a score of 0, 9% with a score of 1, 27% with a score of 2 and 50% with a score≥3.

CONCLUSIONS

The risk score, composed of clinical parameters and BNP, may predict long-term mortality in ischemic stroke survivors.

N-Terminal Pro-Brain Natriuretic Peptide Shows Diagnostic Accuracy for Detecting Atrial Fibrillation in Cryptogenic Stroke Patients

Background

Diagnosing paroxysmal atrial fibrillation in patients with stroke can be difficult. We aimed to determine if N-terminal pro-brain natriuretic peptide can help identify paroxysmal atrial fibrillation in cryptogenic stroke.

Methods and results

Among 264 ischemic stroke patients, serum levels of N-terminal pro-brain natriuretic peptide were measured within 72 h of stroke onset. In cryptogenic stroke patients, 24-h Holter monitoring was used to look for paroxysmal atrial fibrillation within the first week and also three-and six-months after admission. First, patients with a defined etiology were used to construct a receiver operating characteristic curve for the diagnosis of atrial fibrillation. From this curve, the sensitivity and specificity of preestablished cutoff points for the diagnosis of atrial fibrillation were calculated. A logistic regression was performed to assess the independent relationship of the logarithm of N-terminal pro-brain natriuretic peptide levels with atrial fibrillation. The cutoff points were then evaluated in patients with cryptogenic stroke.

Results

One hundred eighty-four patients had a specific stroke etiology. Fifty-five patients had atrial fibrillation. Using multivariate analysis, the logarithm of N-terminal pro-brain natriuretic peptide levels was independently associated with atrial fibrillation. The area under the receiver operating characteristic curve of N-terminal pro-brain natriuretic peptide for the diagnosis of atrial fibrillation was 0·91 (95% confidence interval 0·87–0·95). The cutoff point of 265·5 pg/ml had a sensitivity of 100% and specificity of 70·5% for the diagnosis of atrial fibrillation. The cutoff point of 912 pg/ml had a sensitivity of 81·8% and a specificity of 87·5%. Eighty patients had a cryptogenic stroke. In 17, paroxysmal atrial fibrillation was found during follow-up. In these patients, the area under the curve for the diagnosis of paroxysmal atrial fibrillation was 0·83. The cutoff point of 265·5 had a sensitivity of 88·2% and a specificity of 61·9%. The cutoff point of 912 pg/ml had a sensitivity of 47·1% and a specificity of 88·9%.

Conclusion

N-terminal pro-brain natriuretic peptide has good accuracy in predicting the presence of paroxysmal atrial fibrillation in patients with cryptogenic stroke and can help to identify these patients.

N-terminal pro-brain natriuretic peptide level determined at different times identifies transient ischaemic attack patients with atrial fibrillation

BACKGROUND AND PURPOSE

The etiological classification of patients with transient ischaemic attack (TIA) is a difficult endeavor and the use of serum biomarkers could improve the diagnostic accuracy. The aim of this study was to correlate atrial fibrillation, the main cardioembolic etiology (CE), with different serum biomarkers measured in consecutive TIA patients.

METHODS

The concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha, neuron-specific enolase, high-sensitivity C-reactive protein, IL-1-α and the N-terminal pro-B type natriuretic peptide (NT-proBNP) were quantified in the serum of 140 patients with TIA and 44 non-stroke subjects. Measurements were performed at different times throughout evolution: within 24 h of symptoms onset and at days 7 and 90.

RESULTS

With the exception of IL-6, all biomarkers were higher in TIA patients than in controls. NT-proBNP was significantly related to the presence or new diagnosis of AF at all time points analyzed. Furthermore, the baseline NT-proBNP level was significantly higher than values at the 7-day and 90-day follow-up. For this reason, different cut-off values were obtained at different times: 313 pg/ml at baseline [odds ratio (OR) = 18.99, P < 0.001], 181 pg/ml at 7 days (OR = 11.4, P = 0.001) and 174 pg/ml (OR = 8.46, P < 0.001) at 90 days.

CONCLUSION

High levels of NT-proBNP determined during the first 3 months after a TIA were associated with AF. Consequently, this biomarker may be useful to reclassify undetermined TIA patients as having disease of CE.

Association of perioperative troponin and atrial fibrillation after coronary artery bypass grafting

OBJECTIVES

Prediction of atrial fibrillation (AF) after coronary artery bypass grafting (CABG) may lead to preventive or early treatment and improved outcome. We investigated the association of serial perioperative cardiac troponin T (cTNT) measurements with postoperative AF in patients undergoing CABG.

METHODS

In a retrospective analysis of prospectively collected data, 3148 patients undergoing elective CABG were evaluated. cTNT values were routinely determined before the start of surgery (cTNT0), at arrival on the intensive care unit (cTNT1) and 8-12 h later (cTNT2). Measurement of cTNT was continued until the peak value was reached. The development of AF during hospital stay was scored. The association between cTNT (cTNT0, cTNT1, cTNT2 and cTNTmax in first 48 h) and AF was calculated in univariable and multivariable analysis.

RESULTS

AF occurred in 1080 (34%) patients. cTNT0, cTNT2 and cTNTmax were significantly and positively associated with postoperative AF (P < 0.001) in a univariable analysis, whereas a trend was seen for cTNT1 (P = 0.051). Advanced age, inotropic support and postoperative infection were independently associated with postoperative AF after logistic regression analysis, but cTNT was not. Categorizing patients by inotropic support into categories of inotropic support duration (none, <48 h, >48 h), the mean cTNT values were significantly higher among patients with AF in each category (all P < 0.001). Perioperative cTNT was significantly higher in patients with postoperative complications, longer hospital stay and reduced in-hospital survival.

CONCLUSIONS

Perioperative cTNT is univariably associated with postoperative AF after CABG, but not independently. Further, no clinically useful cut-off point for preventive or early treatment could be identified. Both perioperative cTNT and postoperative AF are associated with negative outcome and prolonged hospital stay.

A simple score for predicting paroxysmal atrial fibrillation in acute ischemic stroke

BACKGROUND AND PURPOSE

Our aim in this study was to investigate factors associated with paroxysmal atrial fibrillation (PAF) in acute stroke patients and to develop a risk score to predict the presence of PAF.

METHODS

We retrospectively enrolled patients with acute ischemic stroke within 24h of onset between June 2006 and April 2008. Patients with sustained AF were excluded. Patients were divided into two groups according to the presence of PAF: the PAF group or the non-PAF group. The clinical factors associated with PAF were investigated. Furthermore, we devised a new risk score to predict the presence of PAF.

RESULTS

There were 215 patients enrolled. The PAF group had 32 (14.9%) patients. Multivariate logistic regression analysis demonstrated that NIHSS score≥8 (OR, 4.2; 1.38-12.88), left atrial size≥3.8 cm (OR, 4.8; 1.65-13.66), mitral valvular disease (OR, 7.5; 2.17-25.90), and plasma BNP level≥144 pg/ml (OR, 12.8; 4.12-40.00) were independent factors associated with PAF. We developed a risk score from these variables (total score 0 to 5): NIHSS score≥8 (1 point); left atrial size≥3.8 cm (1 point); mitral valvular disease (1 point); and BNP level≥144 pg/ml (2 points). The frequency of PAF was 0% with a score of 0, 4% with a score of 1, 14% with a score of 2, 26% with a score of 3, 50% with a score of 4 and 100% with a score of 5

CONCLUSION

Our simple score can predict the presence of PAF during hospitalization in acute ischemic stroke.

Brain natriuretic peptide: a relevant marker to rule out delayed atrial fibrillation in stroke patient

Detection of new atrial fibrillation (AF) after ischemic stroke is challenging. The aim of the TARGET-AF study was to identify relevant markers for ruling out delayed AF in stroke patients. Early and prolonged Holter electrocardiography (ECG) monitoring during hospitalization was performed systematically in consecutive acute stroke patients naive to AF (no history of AF or no AF on baseline ECG). All clinical and paraclinical data for routine etiologic assessment were collected. The diagnostic value of all parameters significantly associated with AF was assessed by comparison of area under the receiver operating characteristic curve (AUC). Of the 300 stroke patients enrolled (mean age, 62.5 ± 15.5 years; sex ratio: 1.7; mean National Institutes of Health Stroke Scale score, 7.1 ± 7.9, median duration of Holter ECG monitoring, 6.8 days), 52 (17.3%) had newly diagnosed AF. Parameters significantly associated with AF were classified by increasing AUC: anterior circulation localization (AUC, 0.604; 95% confidence interval [CI], 0.546-0.660), P-wave initial force (AUC, 0.608; 95% CI, 0.545-0.669), left atrial dilatation (AUC, 0.657; 95% CI, 0.600-0.711), National Institutes of Health Stroke Scale score (AUC, 0.667; 95% CI, 0.611-0.720), sex (AUC, 0.683; 95% CI, 0.627-0.736), age (AUC, 0.755; 95% CI, 0.707-0.797), CHA2DS2-VASc score (AUC, 0.796; 95% CI, 0.746-0.841), STAF (score for the targeting of AF) score (AUC, 0.842; 95% CI, 0.796-0.882), and plasma brain natriuretic peptide (BNP) level (AUC, 0.868; 95% CI, 0.825-0.904). The use of all parameters combined (AUC, 0.910; 95% CI, 0.872-0.940) was not significantly more efficient in diagnosing AF than BNP alone (P = .248). At the Youden plot, the diagnostic properties for BNP >131 pg/mL were sensitivity, 98.1% (95% CI, 89.7-99.7); specificity, 71.4% (95% CI, 65.3-76.9); and negative predictive value, 99.4% (95% CI, 96.9-99.9). Our data indicate that a BNP level ≤ 131 pg/mL might rule out delayed AF in stroke survivors and could be included in algorithms for AF detection.

Biomarker level improves the diagnosis of embolic source in ischemic stroke of unknown origin

The risk of recurrent stroke is likely related to etiology. Therefore it is important to identify which patients are at highest early risk. We evaluated whether selected blood biomarkers may aid in the diagnosis of stroke etiology. We studied consecutive non-lacunar stroke patients between November 2006 and January 2007, and selected undetermined origin strokes. Blood samples were drawn at arrival to test brain natriuretic peptide (BNP), D-dimer, CK-MB, myoglobin, and troponin. Second harmonic transthoracic echocardiography (SHTTE) and ECG-24 h monitoring were also performed within the first 24 h. We evaluated 294 patients with ischemic stroke; 89 had an initial undetermined origin. After a cardiological work-up, 49 were diagnosed as embolic including atrial fibrillation (4), severe aortic arch atheromatosis (24), severe wall abnormalities (12), valve disease (3), dilated cardiomyopathy (1), and patent foramen (5). Higher levels of CK-MB, BNP, and myoglobin were found in patients with embolic source in SHTTE, but only CK-MB >1.5 ng/ml and BNP >64 pg/ml remained as independent predictors: BNP (OR 8.86; CI 95 % 2.79-28.09), CK-MB (OR 6.28; CI 95 % 1.66-23.69). BNP showed specificity of 75 %, sensitivity of 63.4 %, and positive predictive value (PPV) of 75.6 %. CK-MB had specificity of 85 %, sensitivity of 47.9 %, and PPV of 79.3 %. Measuring both biomarkers improves the finding of embolic source, increasing specificity to 95 % and PPV to 88.2 %. High-level CK-MB and BNP during the acute phase of ischemic stroke are associated with an embolic source. Measurement of both biomarkers may improve the diagnosis, guiding the need to perform a heart exploration.

Brain natriuretic peptide levels as a predictor for new atrial fibrillation during hospitalization in patients with acute ischemic stroke

The aim of this study was to investigate the relation between brain natriuretic peptide (BNP) levels and the detection rate of new documented atrial fibrillation (AF) after ischemic stroke. Consecutive patients with ischemic stroke prospectively enrolled within 24 hours of onset. Patients with AF on admission electrocardiography or with histories of AF were excluded. The plasma BNP level was measured on admission, and the factors associated with new documented AF were investigated by multivariate logistic regression analysis. Furthermore, the detection rates of AF according to BNP level were evaluated. A total of 584 patients were enrolled. AF was detected in 40 patients (new AF group; 6.8%). The median BNP level of the new AF group was significantly higher than for the non-AF group (186.6 pg/ml [interquartile range 68.7 to 386.3] vs 35.2 pg/ml [interquartile range 15.9 to 80.1], p <0.0001). The cut-off level, sensitivity, and specificity of BNP levels to distinguish the new AF group from the non-AF group were 65.0 pg/ml, 80%, and 70%, respectively. Multivariate logistic regression analysis demonstrated that National Institutes of Health Stroke Scale score >7 (odds ratio 3.4, 95% confidence interval 1.685 to 7.006, p = 0.0007) and a plasma BNP level >65.0 pg/ml (odds ratio 6.8, 95% confidence interval 2.975 to 15.359, p <0.0001) were independently associated with new AF. The detection rates of AF according to BNP level were as follows: 2% of patients with <50 pg/ml, 4% of those with 50 to <100 pg/ml, 12% of those with 100 to <200 pg/ml, 26% of those with 200 to <400 pg/ml, and 38% of those with ≥400 pg/ml. In conclusion, BNP levels can predict new AF in patients with acute ischemic stroke. Elevated BNP levels result in an increase in the frequency of detection of new AF.

Natriuretic peptides for the detection of paroxysmal atrial fibrillation in patients with cerebral ischemia--the Find-AF study

Background and Purpose

Diagnosis of paroxysmal atrial fibrillation (AF) can be challenging, but it is highly relevant in patients presenting with sinus rhythm and acute cerebral ischemia. We aimed to evaluate prospectively whether natriuretic peptide levels and kinetics identify patients with paroxysmal AF.

Methods

Patients with acute cerebral ischemia were included into the prospective observational Find-AF study. N-terminal pro brain-type natriuretic peptide (NT-proBNP), brain-type natriuretic peptide (BNP) and N-terminal pro atrial-type natriuretic peptide (NT-proANP) plasma levels were measured on admission, after 6 and 24 hours. Patients free from AF at presentation received 7 day Holter monitoring. We prospectively hypothesized that patients presenting in sinus rhythm with NT-proBNP>median were more likely to have paroxysmal AF than patients with NT-proBNP<median.

Results

281 patients were included, of whom 237 (84.3%) presented in sinus rhythm. 220 patients naïve to AF with an evaluable prolonged Holter ECG were analysed. In patients with NT-proBNP>median (239 pg/ml), 17.9% had paroxysmal AF in contrast to 7.4% with NT-proBNP<239 pg/ml (p = 0.025). The ratio of early (0 h) to late (24 h) plasma levels of NT-proBNP showed no difference between both groups. For the detection of paroxysmal atrial fibrillation, BNP, NT-proBNP and NT-proANP at admission had an area under the curve in ROC analysis of 0.747 (0.663–0.831), 0.638 (0.531–0.744) and 0.663 (0.566–0.761), respectively. In multivariate analysis, BNP was the only biomarker to be independently predictive for paroxysmal atrial fibrillation.

Conclusions

BNP is independently predictive of paroxysmal AF detected by prolonged ECG monitoring in patients with cerebral ischemia and may be used to effectively select patients for prolonged Holter monitoring.

N-Terminal Probrain Natriuretic Peptide as a Biomarker of Cardioembolic Stroke

Background and purpose

N-terminal probrain natriuretic peptide, which is mainly produced by the heart, is increased in acute stroke. We aimed to determine if N-terminal probrain natriuretic peptide could be a biomarker for ischemic stroke with a cardioembolic cause.

Methods

Consecutive sample of acute stroke patients admitted to a Stroke Unit. Ischemic stroke subtype was classified using the TOAST classification. Blood samples were drawn within 72 h after stroke onset. Serum N-terminal probrain natriuretic peptide concentration was measured using an electrochemiluminescence immunoassay. Mean values of N-terminal probrain natriuretic peptide were compared between patients with hemorrhagic stroke vs. ischemic stroke, cardioembolic stroke vs. noncardioembolic stroke, cardioembolic stroke with atrial fibrillation vs. noncardioembolic stroke using t-test. Receiver operating characteristic curves were used to test the ability of N-terminal probrain natriuretic peptide values to identify cardioembolic stroke and cardioembolic stroke with atrial fibrillation.

Results

Ninety-two patients were included (66 with ischemic stroke) with a mean age of 58·6 years. Twenty-eight (42·4%) ischemic strokes had a cardioembolic cause. Mean N-terminal probrain natriuretic peptide values for cardioembolic stroke were significantly higher ( P < 0·001) (491·6; 95% confidence interval 283·7–852·0 pg/ml) than for noncardioembolic ischemic stroke (124·7; 86·3–180·2 pg/ml). The area under the receiver operating characteristic curve for N-terminal probrain natriuretic peptide in cardioembolic stroke was 0·77. The cut-off point with the highest sensitivity and specificity was set at 265·5 pg/ml (71·4% and 73·7% respectively). The area under the curve of N-terminal probrain natriuretic peptide for cardioembolic stroke related to atrial fibrillation was 0·92, cut-off was set at 265·5 pg/ml (sensitivity 94·4%, specificity 72·9%).

Conclusion

N-terminal probrain natriuretic peptide is a biomarker with a good accuracy to predict ischemic stroke of cardioembolic cause, namely associated with atrial fibrillation.