Midregional proatrial natriuretic peptide improves risk stratification after ischemic stroke

MR-proANP levels in Acute ischemic stroke and clinical outcomes: a systematic review and meta-analysis

In patients with acute ischemic stroke, midregional proatrial natriuretic peptide (MR-proANP) has shown promise in preliminary studies for risk stratification. The objective of this study is to evaluate the prognostic utility of MR-proANP in AIS, focusing on its ability to predict 90-day functional outcomes, mortality rates, and the presence of atrial fibrillation (Afib). A comprehensive literature search was conducted using PubMed, Web of Science, and Scopus, following PRISMA guidelines. The search strategy employed a combination of keywords and index terms including "Acute Ischemic Stroke," "AIS," "Cerebral Infarction," "Atrial Fibrillation," "AFib," "stroke," "MR-proANP," "Mid-regional pro-atrial natriuretic peptide," and "proatrial natriuretic peptide." Inclusion criteria encompassed any study focusing on MR-proANP and ischemic stroke, published up to October 15, 2023. Primary end points were newly diagnosed Afib, 90-day Modified Rankin Scale (mRS) score, and 90-day mortality. Studies were described in narrative and tabular form. Risk of bias was assessed using the ROBINS-I tool. Pooled estimates for our key end points were generated using a random effects model where appropriate. MR-proANP levels were significantly elevated in newly diagnosed Afib patients compared to no Afib patients (mean difference (MD): 134.4 pmol/l; 95% confidence interval (CI): 119.45 to 149.35, P < 0.0001). Unfavorable functional outcomes, as measured by mRS scores of ≥ 3 at 90 days, were associated with higher levels of MR-proANP (MD: 93.87 pmol/; 95% CI: 76.66 to 111.09, P < 0.0001). Elevated MR-proANP levels were also strongly correlated with increased 90-day mortality rates (MD: 164.43 pmol/; CI: 95.94 to 232.92, P < 0.0001). MR-proANP was significantly associated with functional outcomes, 90-day mortality, and the newly diagnosed AF. The limited number of studies included calls for further large-scale research to confirm these findings and explore the potential for expedited diagnostic procedures and targeted interventions like anticoagulant therapy.

Natriuretic Peptides to Classify Risk of Atrial Fibrillation Detection After Stroke: Analysis of the BIOSIGNAL and PRECISE Cohort Studies

BACKGROUND AND OBJECTIVES

Prolonged cardiac monitoring (PCM) increases atrial fibrillation (AF) detection after ischemic stroke, but access is limited, and it is burdensome for patients. Our objective was to assess whether midregional proatrial natriuretic peptide (MR-proANP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) could classify people who are unlikely to have AF after ischemic stroke and allow better targeting of PCM.

METHODS

We analyzed people from the Biomarker Signature of Stroke Aetiology (BIOSIGNAL) study with ischemic stroke, no known AF, and ≥3 days cardiac monitoring. External validation was performed in the Preventing Recurrent Cardioembolic Stroke: Right Approach, Right Patient (PRECISE) study of 28 days of cardiac monitoring in people with ischemic stroke or transient ischemic attack and no known AF. The main outcome is no AF detection. We assessed the discriminatory value of MR-proANP and NT-proBNP combined with clinical variables to identify people with no AF. A decision curve analysis was performed with combined data to determine the net reduction in people who would undergo PCM using the models based on a 15% threshold probability for AF detection.

RESULTS

We included 621 people from the BIOSIGNAL study. The clinical multivariable prediction model included age, NIH Stroke Scale score, lipid-lowering therapy, creatinine, and smoking status. The area under the receiver-operating characteristic curve (AUROC) for clinical variables was 0.68 (95% CI 0.62-0.74), which improved with the addition of log10MR-proANP (0.72, 0.66-0.78; p = 0.001) or log10NT-proBNP (0.71, 0.65-0.77; p = 0.009). Performance was similar for the models with log10MR-proANP vs log10NT-proBNP (p = 0.28). In 239 people from the PRECISE study, the AUROC for clinical variables was 0.68 (0.59-0.76), which improved with the addition of log10NT-proBNP (0.73, 0.65-0.82; p < 0.001) or log10MR-proANP (0.79, 0.72-0.86; p < 0.001). Performance was better for the model with log10MR-proANP vs log10NT-proBNP (p = 0.03). The models could reduce the number of people who would undergo PCM by 30% (clinical and log10MR-proANP), 27% (clinical and log10NT-proBNP), or 20% (clinical only).

DISCUSSION

MR-proANP and NT-proBNP help classify people who are unlikely to have AF after ischemic stroke. Measuring MR-proANP or NT-proBNP could reduce the number of people who need PCM by 30%, without reducing the amount of AF detected.

TRIAL REGISTRATION INFORMATION

NCT02274727; clinicaltrials.gov/study/NCT02274727.

Embolic Stroke of Undetermined Source: New Data and New Controversies on Cardiac Monitoring and Anticoagulation

Embolic strokes of undetermined source (ESUS) represent 9%-25% of all ischemic strokes. Based on the suspicion that a large proportion of cardioembolic sources remain undetected among embolic stroke of undetermined source patients, it has been hypothesized that a universal approach of anticoagulation would be better than aspirin for preventing recurrent strokes. However, 4 randomized controlled trials (RCTs), with different degrees of patient selection, failed to confirm this hypothesis. In parallel, several RCTs consistently demonstrated that prolonged cardiac monitoring increased atrial fibrillation detection and anticoagulation initiation compared with usual care in patients with ESUS, and later in individuals with ischemic stroke of known cause (e.g., large or small vessel disease). However, none of these trials or subsequent meta-analyses of all available RCTs have shown a reduction in stroke recurrence associated with the use of prolonged cardiac monitoring. In this article, we review the clinical and research implications of recent RCTs of antithrombotic therapy in patients with ESUS and in high-risk populations with and without stroke, with device-detected asymptomatic atrial fibrillation.

Cardiac Blood-Based Biomarkers of Myocardial Stress as Predictors of Atrial Fibrillation Development in Patients With Embolic Stroke of Undetermined Source/Cryptogenic Stroke: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

Undiagnosed atrial fibrillation (AF) is a major risk factor for stroke that can go unnoticed in individuals with embolic stroke of undetermined source (ESUS) or cryptogenic stroke (CS). Early detection is critical for stroke prognosis and secondary prevention. This study aimed to determine if blood biomarkers of myocardial stress can accurately predict AF in patients with ESUS/CS, which would allow the identification of those who would benefit from closer monitoring.

METHODS

In February 2023 we performed a systematic date-unrestricted search of three databases for studies on patients with ESUS/CS who were subsequently diagnosed with AF. We examined the relationships between AF and serum myocardial stress markers such as brain natriuretic peptide (BNP), N-terminal-pro-BNP (NT-proBNP), midregional proatrial natriuretic peptide, and troponin.

RESULTS

Among the 1,527 studies reviewed, 23 eligible studies involving 6,212 participants, including 864 with AF, were analyzed. A meta-analysis of 9 studies indicated that they demonstrated a clear association between higher NT-proBNP levels and an increased risk of AF, with adjusted and raw data indicating 3.06- and 9.03-fold higher AF risks, respectively. Lower NT-proBNP levels had a pooled negative predictive value of 91.7%, indicating the potential to rule out AF with an 8% false-negative rate.

CONCLUSIONS

Further research is required to fully determine the potential of biomarkers for AF detection after stroke, as results from previous studies lack homogeneity. However, lower NT-proBNP levels have potential in ruling out AF in patients with ESUS/CS. Combining them with other relevant biomarkers may enhance the precision of identifying patients who will not benefit from extended monitoring, which would optimize resource allocation and patient care.

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.

European Stroke Organisation (ESO) guideline on screening for subclinical atrial fibrillation after stroke or transient ischaemic attack of undetermined origin

We aimed to provide practical recommendations for the screening of subclinical atrial fibrillation (AF) in patients with ischaemic stroke or transient ischaemic attack (TIA) of undetermined origin. These guidelines are based on the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. Five relevant Population, Intervention, Comparator, Outcome questions were defined by a multidisciplinary module working group (MWG).

Longer duration of cardiac rhythm monitoring increases the detection of subclinical AF, but the optimal monitoring length is yet to be defined. We advise longer monitoring to increase the rate of anticoagulation, but whether longer monitoring improves clinical outcomes needs to be addressed. AF detection does not differ from in- or out-patient ECG-monitoring with similar monitoring duration, so we consider it reasonable to initiate in-hospital monitoring as soon as possible and continue with outpatient monitoring for more than 48h. Although insertable loop recorders (ILR) increase AF detection based on their longer monitoring duration, comparison with non-implantable ECG devices for similar monitoring time is lacking. We suggest the use of implantable devices, if feasible, for AF detection instead of non- implantable devices to increase the detection of subclinical AF. There is weak evidence of a useful role for blood, ECG, and brain imaging biomarkers for the identification of patients at high risk of AF. In patients with patent foramen ovale, we found insufficient evidence from RCT, but prolonged cardiac monitoring in patients >55 years is advisable for subclinical AF detection. To conclude, in adult patients with ischaemic stroke or TIA of undetermined origin, we recommend longer duration of cardiac rhythm monitoring of more than 48h and if feasible with IRL to increase the detection of subclinical AF.

Measurement of Midregional Pro-Atrial Natriuretic Peptide to Discover Atrial Fibrillation in Patients With Ischemic Stroke

BACKGROUND

Midregional pro-atrial natriuretic peptide (MR-proANP) is a promising biomarker to differentiate the underlying etiology of acute ischemic stroke (AIS).

OBJECTIVES

This study aimed to determine the role of MR-proANP for classification as cardioembolic (CE) stroke, identification of newly diagnosed atrial fibrillation (NDAF), and risk assessment for major adverse cardiovascular events (MACE).

METHODS

This study measured MR-proANP prospectively collected within 24 hours after symptom-onset in patients with AIS from the multicenter BIOSIGNAL (Biomarker Signature of Stroke Aetiology) cohort study. Primary outcomes were CE stroke etiology and NDAF after prolonged cardiac monitoring, as well as a composite outcome of MACE (recurrent cerebrovascular events, myocardial infarction, or cardiovascular death) within 1 year. Logistic/Poisson and subproportional hazard regression were applied to evaluate the association between MR-proANP levels and outcomes. Additionally, a model for prediction of NDAF was derived and validated as a decision tool for immediate clinical application.

RESULTS

Between October 1, 2014, and October 31, 2017, this study recruited 1,759 patients. Log₁₀MR-proANP levels were associated with CE stroke (OR: 7.96; 95% CI: 4.82-13.14; risk ratio: 3.12; 95% CI: 2.23-4.37), as well as NDAF (OR: 35.3; 95% CI: 17.58-71.03; risk ratio: 11.47; 95% CI: 6.74-19.53), and MACE (subdistributional HR: 2.02; 95% CI: 1.32-3.08) during follow-up. The model to predict NDAF including only age and MR-proANP levels had a good discriminatory capacity with an area under the curve of 0.81 (95% CI: 0.76-0.86), was well calibrated (calibration in the large: -0.086; calibration slope 1.053), and yielded higher net-benefit compared with validated scores to predict NDAF (AS5F score, CHA₂DS₂-VASc [Congestive Heart Failure, Hypertension, Age ≥65 or ≥75, Diabetes, Prior Cardioembolic Event, (female) Sex, or Vascular Disease] score).

CONCLUSIONS

MR-proANP is a valid biomarker to determine risk of NDAF and MACE in patients with AIS and can be used as a decision tool to identify patients for prolonged cardiac monitoring. (Biomarker Signature of Stroke Aetiology Study: The BIOSIGNAL study [BIOSIGNAL]; NCT02274727).

Circulating Biomarkers in Long-Term Stroke Prognosis: A Scoping Review Focusing on the South African Setting

Cerebrovascular disease, including both ischaemic and haemorrhagic strokes, remains one of the highest causes of global morbidity and mortality. Developing nations, such as South Africa (SA), are affected disproportionately. Early identification of stroke patients at risk of poor clinical prognosis may result in improved outcomes. In addition to conventional neuroimaging, the role of predictive biomarkers has been shown to be important. Little data exist on their applicability within SA. This scoping review aimed to evaluate the currently available data pertaining to blood biomarkers that aid in the long-term prognostication of patients following stroke and its potential application in the South African setting. This scoping review followed a 6-stage process to identify and critically review currently available literature pertaining to prognostic biomarkers in stroke. An initial 1191 articles were identified and, following rigorous review, 41 articles were included for the purposes of the scoping review. A number of potential biomarkers were identified and grouped according to the function or origin of the marker. Although most biomarkers showed great prognostic potential, the cost and availability will likely limit their application within SA. The burden of stroke is increasing worldwide and appears to be affecting developing countries disproportionately. Access to neuroradiological services is not readily available in all settings and the addition of biomarkers to assist in the long-term prognostication of patients following a stroke can be of great clinical value. The cost and availability of many of the reviewed biomarkers will likely hinder their use in the South African setting.

Precision medicine in secondary prevention of ischemic stroke: how may blood-based biomarkers help in clinical routine? An expert opinion

PURPOSE OF REVIEW

One in eight patients unfortunately suffers a new stroke within 5 years of their first stroke, even today. Research in precision medicine could lead to a more individualized treatment allocation, possibly achieving lower recurrence rates of ischemic stroke. In this narrative review, we aim to discuss potential clinical implementation of several promising candidate blood biomarkers.

RECENT FINDINGS

We discuss specifically some promising blood-based biomarkers, which may improve the identification of underlying causes as well as risk stratification of patients according to their specific cerebrovascular risk factor pattern.

SUMMARY

Multimodal profiling of ischemic stroke patients by means of blood biomarkers, in addition to established clinical and neuroradiological data, may allow in the future a refinement of decision algorithms for treatment allocation in secondary ischemic stroke prevention.

Biomarkers for Atrial Fibrillation Detection After Stroke: Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

To identify clinical, ECG, and blood-based biomarkers associated with atrial fibrillation (AF) detection after ischaemic stroke or TIA that could help inform patient selection for cardiac monitoring.

METHODS

We performed a systematic review and meta-analysis and searched electronic databases for cohort studies from January 15, 2000, to January 15, 2020. The outcome was AF ≥30 seconds within 1 year after ischemic stroke/TIA. We used random effects models to create summary estimates of risk. Risk of bias was assessed using the Quality in Prognostic Studies tool.

RESULTS

We identified 8,503 studies, selected 34 studies, and assessed 69 variables (42 clinical, 20 ECG, and 7 blood-based biomarkers). The studies included 11,569 participants and AF was detected in 1,478 (12.8%). Overall, risk of bias was moderate. Variables associated with increased likelihood of AF detection are older age (odds ratio [OR] 3.26, 95% confidence interval [CI] 2.35-4.54), female sex (OR 1.47, 95% CI 1.23-1.77), a history of heart failure (OR 2.56, 95% CI 1.87-3.49), hypertension (OR 1.42, 95% CI 1.15-1.75) or ischemic heart disease (OR 1.80, 95% CI 1.34-2.42), higher modified Rankin Scale (OR 6.13, 95% CI 2.93-12.84) or National Institutes of Health Stroke Scale score (OR 2.50, 95% CI 1.64-3.81), no significant carotid/intracranial artery stenosis (OR 3.23, 95% CI 1.14-9.11), no tobacco use (OR 1.93, 95% CI 1.48-2.51), statin therapy (OR 2.07, 95% CI 1.14-3.73), stroke as index diagnosis (OR 1.59, 95% CI 1.17-2.18), systolic blood pressure (OR 1.61, 95% CI 1.16-2.22), IV thrombolysis treatment (OR 2.40, 95% CI 1.83-3.16), atrioventricular block (OR 2.12, 95% CI 1.08-4.17), left ventricular hypertrophy (OR 2.21, 95% CI 1.03-4.74), premature atrial contraction (OR 3.90, 95% CI 1.74-8.74), maximum P-wave duration (OR 3.19, 95% CI 1.40-7.25), PR interval (OR 2.32, 95% CI 1.11-4.83), P-wave dispersion (OR 7.79, 95% CI 4.16-14.61), P-wave index (OR 3.44, 95% CI 1.87-6.32), QTc interval (OR 3.68, 95% CI 1.63-8.28), brain natriuretic peptide (OR 13.73, 95% CI 3.31-57.07), and high-density lipoprotein cholesterol (OR 1.49, 95% CI 1.17-1.88) concentrations. Variables associated with reduced likelihood are minimum P-wave duration (OR 0.53, 95% CI 0.29-0.98), low-density lipoprotein cholesterol (OR 0.73, 95% CI 0.57-0.93), and triglyceride (OR 0.51, 95% CI 0.41-0.64) concentrations.

DISCUSSION

We identified multimodal biomarkers that could help guide patient selection for cardiac monitoring after ischaemic stroke/TIA. Their prognostic utility should be prospectively assessed with AF detection and recurrent stroke as outcomes.

Update on Biomarkers Associated to Cardioembolic Stroke: A Narrative Review

Background: In the last years, several studies were conducted that evaluated biomarkers that could be helpful for cardioembolic stroke diagnosis, prognosis, and the determination of risk of stroke recurrence. Methods: We performed a narrative review of the main studies that evaluated biomarkers related to specific cardioembolic causes: atrial fibrillation, patent foramen ovale, atrial cardiomyopathy, and left ventricular wall motion abnormalities. Results: BNP and NT-proBNP are, among all biomarkers of cardioembolic stroke, the ones that have the highest amount of evidence for their use. NT-proBNP is currently used for the selection of patients that will be included in clinical trials that aim to evaluate the use of anticoagulation in patients suspected of having a cardioembolic stroke and for the selection of patients to undergo cardiac monitoring. NT-proBNP has also been incorporated in tools used to predict the risk of stroke recurrence (ABC-stroke score). Conclusions: NT-proBNP and BNP continue to be the biomarkers most widely studied in the context of cardioembolic stroke. The possibility of using other biomarkers in clinical practice is still distant, mainly because of the low methodological quality of the studies in which they were evaluated. Both internal and external validation studies are rarely performed for most biomarkers.

Mid-regional pro-atrial natriuretic peptide levels before and after hemodialysis predict long-term prognosis

BACKGROUND

Mid-regional pro-atrial natriuretic peptide (MR-proANP) is a strong prognostic biomarker in cardiovascular disease but there is limited data for its use among patients undergoing dialysis.

METHODS

This was a cohort study of patients receiving maintenance hemodialysis from two Danish centers. Blood sampling and echocardiography were performed before and after a dialysis session. We calculated the area under the curve (AUC) for the receiver operating characteristics for diagnosing heart failure and Cox regressions for cardiovascular events and all-cause mortality.

RESULTS

Of the 306 patients, 284 (93%) had MR-proANP measurements both before and after dialysis. Median concentration was 642 pmol/L (IQR 419-858) before and 351 pmol/L (IQR 197-537) after dialysis, a mean decrease of 330 pmol/L (43%, CI 296-364, P < 0.001). MR-proANP concentration both before and after dialysis was negatively correlated to left ventricular ejection fraction with no difference in predictive ability for heart failure, AUC before and after dialysis were 0.60 (CI 0.50-0.70) and 0.61 (CI 0.51-0.71) (P = 0.40). Median follow-up was 32 months (IQR 31-33), during which 99 patients (32%) had a cardiovascular event and 110 (36%) died. A doubling of MR-proANP concentration was associated with a hazard ratio (HR) of 1.6 (CI 1.3-1.9) before and 1.7 (CI 1.4-2.0) after dialysis for mortality and a HR of 1.5 (CI 1.2-1.9) before and 1.4 (CI 1.2-1.7) after dialysis for cardiovascular events (all P < 0.001).

CONCLUSION

The MR-proANP concentration is elevated among patients undergoing hemodialysis and decreases during dialysis. MR-proANP concentration both before, after and intra-dialysis change strongly predicted cardiovascular events and all-cause mortality.

Promising Biomarker Candidates for Cardioembolic Stroke Etiology. A Brief Narrative Review and Current Opinion

Determining the cause of stroke is considered one of the main objectives in evaluating a stroke patient in clinical practice. However, ischemic stroke is a heterogeneous disorder and numerous underlying disorders are implicated in its pathogenesis. Although progress has been made in identifying individual stroke etiology, in many cases underlying mechanisms still remain elusive. Since secondary prevention strategies are tailored toward individual stroke mechanisms, patients whose stroke etiology is unknown may not receive optimal preventive treatment. Cardioembolic stroke is commonly defined as cerebral vessel occlusion by distant embolization arising from thrombus formation in the heart. It accounts for the main proportion of ischemic strokes, and its share to stroke etiology is likely to rise even further in future decades. However, it can be challenging to distinguish cardioembolism from other possible etiologies. As personalized medicine advances, stroke researchers' focus is increasingly drawn to etiology-associated biomarkers. They can provide deeper insight regarding specific stroke mechanisms and can help to unravel previously undetected pathologies. Furthermore, etiology-associated biomarkers could play an important role in guiding future stroke prevention strategies. To achieve this, broad validation of promising candidate biomarkers as well as their implementation in well-designed randomized clinical trials is necessary. This review focuses on the most-promising candidates for diagnosis of cardioembolic stroke. It discusses existing evidence for possible clinical applications of these biomarkers, addresses current challenges, and outlines future perspectives.

B-type natriuretic peptide over N-terminal pro-brain natriuretic peptide to predict incident atrial fibrillation after cryptogenic stroke

BACKGROUND AND PURPOSE

B-type natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are well-known surrogates of atrial fibrillation (AF) detection but studies usually present data on either BNP or NT-proBNP. The aim was to determine and directly compare the validity of the two biomarkers as a tool to predict AF and guide prolonged cardiac monitoring in cryptogenic stroke patients.

METHODS

Non-lacunar acute ischaemic stroke (<72 h) patients over 55 years of age with cryptogenic stroke after standard evaluation were included in the Crypto-AF study and blood was collected. BNP and NT-proBNP levels were determined by automated immunoassays. AF was assessed by 28 days' monitoring. Highest (optimizing specificity) and lowest (optimizing sensitivity) quartiles were used as biomarker cut-offs to build predictive models adjusted by sex and age. The integrated discrimination improvement index (IDI) and DeLong test were used to compare the performance of the two biomarkers.

RESULTS

From 320 patients evaluated, 218 were included in the analysis. AF was detected in 50 patients (22.9%). NT-proBNP (P < 0.001) and BNP (P < 0.001) levels were higher in subjects with AF and their levels correlated (r = 0.495, P < 0.001). BNP showed an increased area under the curve (0.720 vs. 0.669; P = 0.0218) and a better predictive capacity (IDI = 3.63%, 95% confidence interval 1.36%-5.91%) compared to NT-proBNP. BNP performed better than NT-proBNP in a specific model (IDI = 3.7%, 95% confidence interval 0.87%-6.5%), whilst both biomarkers performed similarly in the case of a sensitive model.

CONCLUSIONS

Both BNP and NT-proBNP were increased in cryptogenic stroke patients with AF detection. Interestingly, BNP outperforms NT-proBNP, especially in terms of specificity.

Independent Prognostic Value of MRproANP (Midregional Proatrial Natriuretic Peptide) Levels in Patients With Stroke Is Unaltered Over Time

Background and Purpose—

MRproANP (midregional proatrial natriuretic peptide) is known to be independently associated with cardioembolic stroke cause and to improve risk stratification for 90-day mortality when measured within 24 to 72 hours after symptom onset in patients with acute ischemic stroke. However, the optimal time point for assessment remains unclear. This study aimed to evaluate prognostic utility of MRproANP at different time points during the first 5 days of hospitalization in patients with acute ischemic stroke.

Methods—

Samples of MRproANP were collected on admission (<72 hours after onset) and at multiple time points during the first 5 days of hospitalization in 348 consecutively enrolled patients with acute ischemic stroke. The prognostic value for 90-day mortality, 90-day functional outcome, and the association with cardioembolic stroke cause was assessed regarding the time of measurement, and change over time was modeled using generalized estimating equations.

Results—

MRproANP levels modestly decease over the initial 5 days but remain highly predictive for cardioembolic stroke cause (odds ratio, 9.75 [95% CI, 3.2–29]; 10.62 [95% CI, 3.4–33.3]; 10.8 [95% CI, 3.1–37.1]; 19.4 [95% CI, 5.49–68.7] on admission, day 1, 3 and 5) and 90-day mortality (odds ratio, 59.4 [95% CI, 7.4–480.7]; 78.3 [95% CI, 7.9–772.6]; 14.5 [95% CI, 1.4–145]; 19.81 [95% CI, 2.7–143.4] on admission, day 1, 3, and 5). Change over time does not significantly modify the prognostic value of MRproANP ( P =0.65 and P =0.56 for the interaction term in the multivariate model).

Conclusions—

Independent prognostic value of MRproANP remains unaltered in the acute phase of stroke at least up to 5 days; repeated measurements do not improve the prognostic value.

NfL (Neurofilament Light Chain) Levels as a Predictive Marker for Long-Term Outcome After Ischemic Stroke

Background and Purpose—

Ischemic stroke causes major disability as a consequence of neuronal loss and recurrent ischemic events. Biomarkers predicting tissue damage or stroke recurrence might be useful to guide an individualized stroke therapy. NfL (neurofilament light chain) is a promising biomarker that might be used for this purpose.

Methods—

We used individual data of patients with an acute ischemic stroke and clinical long term follow-up. Serum NfL (sNfL) was quantified within 24 hours after admission and after 1 year and compared with other biomarkers (GDF15 [growth differentiation factor 15], S100, NT-proBNP [N-terminal pro-B-type natriuretic peptide], ANP [atrial natriuretic peptide], and FABP [fatty acid–binding protein]). The primary end point was functional outcome after 90 days and cerebrovascular events and death (combined cardiovascular end point) within 36 months of follow-up.

Results—

Two hundred eleven patients (mean age, 68.7 years; SD, ±12.6; 41.2% women) with median clinical severity on the National Institutes of Health Stroke Scale (NIHSS) score of 3 (interquartile range, 1–5) and long-term follow-up with a median of 41.8 months (interquartile range, 40.0–44.5) were prospectively included. We observed a significant correlation between sNfL and NIHSS at hospital admission (r=0.234; P <0.001). sNfL levels increased with the grade of age-related white matter changes ( P <0.001) and were able to predict unfavorable clinical outcome (modified Rankin Scale score, ≥2) 90 days after stroke (odds ratio [OR], 1.562; 95% CI, 1.003–2.433; P =0.048) together with NIHSS (OR, 1.303; 95% CI, 1.164–1.458; P <0.001) and age-related white matter change rating (severe; OR, 3.326; 95% CI, 1.186–9.326; P =0.022). Similarly, sNfL was valuable for the prediction of the combined cardiovascular end point (OR, 2.002; 95% CI, 1.213–3.302; P =0.007), besides NIHSS (OR, 1.110; 95% CI, 1.000–1.232; P =0.049), diabetes mellitus (OR, 2.942; 95% CI, 1.306–6.630; P =0.005), and age-related white matter change rating (severe; OR, 4.816; 95% CI, 1.206–19.229; P =0.026) after multivariate regression analysis. Kaplan-Meier analysis revealed significantly more combined cardiovascular end points (18 [14.1%] versus 38 [45.8%], log-rank test P <0.001) during long-term follow-up in patients with elevated sNfL levels.

Conclusions—

sNFL is a valuable biomarker for functional independence 90 days after ischemic stroke and predicts cardiovascular long-term outcome.

Clinical Trial Registration—

URL: http://www.isrctn.com . Unique identifier: ISRCTN 46104198.

Development and validation of a score to detect paroxysmal atrial fibrillation after stroke

OBJECTIVE

Prolonged monitoring times (72 hours) are recommended to detect paroxysmal atrial fibrillation (pAF) after ischemic stroke but this is not yet clinical practice; therefore, an individual patient selection for prolonged ECG monitoring might increase the diagnostic yield of pAF in a resource-saving manner.

METHODS

We used individual patient data from 3 prospective studies (n_total = 1,556) performing prolonged Holter-ECG monitoring (at least 72 hours) and centralized data evaluation after TIA or stroke in patients with sinus rhythm. Based on the TRIPOD (Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis) guideline, a clinical score was developed on one cohort, internally validated by bootstrapping, and externally validated on 2 other studies.

RESULTS

pAF was detected in 77 of 1,556 patients (4.9%) during 72 hours of Holter monitoring. After logistic regression analysis with variable selection, age and the qualifying stroke event (categorized as stroke severity with NIH Stroke Scale [NIHSS] score ≤5 [odds ratio 2.4 vs TIA; 95% confidence interval 0.8-6.9, p = 0.112] or stroke with NIHSS score >5 [odds ratio 7.2 vs TIA; 95% confidence interval 2.4-21.8, p < 0.001]) were found to be predictive for the detection of pAF within 72 hours of Holter monitoring and included in the final score (Age: 0.76 points/year, Stroke Severity NIHSS ≤5 = 9 points, NIHSS >5 = 21 points; to Find AF [AS5F]). The high-risk group defined by AS5F is characterized by a predicted risk between 5.2% and 40.8% for detection of pAF with a number needed to screen of 3 for the highest observed AS5F points within the study population. Regarding the low number of outcomes before generalization of AS5F, the results need replication.

CONCLUSION

The AS5F score can select patients for prolonged ECG monitoring after ischemic stroke to detect pAF.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that the AS5F score accurately identifies patients with ischemic stroke at a higher risk of pAF.