Baseline D-Dimer Levels as a Risk Assessment Biomarker for Recurrent Stroke in Patients with Combined Atrial Fibrillation and Atherosclerosis

The Association between Coagulation and Atrial Fibrillation

The existing literature highlights the presence of numerous coagulation factors and markers. Elevated levels of coagulation factors are associated with both existing and newly diagnosed cases of atrial fibrillation (AF). However, this article summarizes the role of coagulation in the pathogenesis of AF, which includes fibrinogen and fibrin, prothrombin, thrombomodulin, soluble urokinase plasminogen activator receptor, von Willebrand factor, P-selectin, D-dimer, plasminogen activator inhibitor-1, and platelet activation. Coagulation irregularities play a significant role in the pathogenesis of AF.

Omega-3 Fatty Acids and Markers of Thrombosis in Patients with Atrial Fibrillation

Omega-3 fatty acids (n-3 FAs) are associated with a lower risk of ischemic stroke in patients with atrial fibrillation (AF). Antithrombotic mechanisms may in part explain this observation. Therefore, we examined the association of n-3 FAs with D-dimer and beta-thromboglobulin (BTG), markers for activated coagulation and platelets, respectively. The n-3 FAs eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), docosapentaenoic acid (DPA) and alpha-linolenic acid (ALA) were determined via gas chromatography in the whole blood of 2373 patients with AF from the Swiss Atrial Fibrillation cohort study (ClinicalTrials.gov Identifier: NCT02105844). In a cross-sectional analysis, we examined the association of total n-3 FAs (EPA + DHA + DPA + ALA) and the association of individual fatty acids with D-dimer in patients with detectable D-dimer values (n = 1096) as well as with BTG (n = 2371) using multiple linear regression models adjusted for confounders. Median D-dimer and BTG levels were 0.340 ug/mL and 448 ng/mL, respectively. Higher total n-3 FAs correlated with lower D-dimer levels (coefficient 0.94, 95% confidence interval (Cl) 0.90-0.98, p = 0.004) and lower BTG levels (coefficient 0.97, Cl 0.95-0.99, p = 0.003). Likewise, the individual n-3 FAs EPA, DHA, DPA and ALA showed an inverse association with D-dimer. Higher levels of DHA, DPA and ALA correlated with lower BTG levels, whereas EPA showed a positive association with BTG. In patients with AF, higher levels of n-3 FAs were associated with lower levels of D-dimer and BTG, markers for activated coagulation and platelets, respectively. These findings suggest that n-3 FAs may exert antithrombotic properties in patients with AF.

Early plasma D-dimer as a predictor of acute intracranial atherosclerosis-related large vessel occlusion in acute ischemic stroke

BACKGROUND

Intracranial atherosclerosis-related large vessel occlusion (ICAS+LVO) poses an important technical challenge for endovascular thrombectomy (EVT).

PURPOSE

To evaluate the value of D-dimer in predicting ICAS+LVO alone and in combination with other clinical and imaging predictors.

MATERIAL AND METHODS

Consecutive patients who underwent EVT at our center between January 2018 and June 2021 were retrospectively reviewed. Patients were classified to the ICAS+LVO or ICAS-LVO group according to angiographic findings. Collateral gradings were evaluated based on computed tomography angiography and categorized as follows: score 0-1 unfavorable collaterals and score 2-3 favorable collaterals. Receiver operating characteristic curve was analyzed to evaluate the predictive value of D-dimer and the combination of other predictors for ICAS+LVO.

RESULTS

A total of 374 patients were enrolled, among them, 107 (28.6%) had an ICAS+LVO, while ICAS-LVO was determined in 267 (71.4%) patients. Median D-dimer levels were lower (0.36 vs. 1.18 mg/L; P < 0.001) while the proportion of favorable collaterals was higher (85.0% vs. 22.5%; P < 0.001) in the ICAS+LVO group than the ICAS-LVO group. After multivariable analysis, D-dimer (adjusted odds ratio [OR]=0.32, 95% confidence interval [CI]=0.21-0.50; P < 0.001) and collaterals (adjusted OR=16.25, 95% CI=7.58-34.84; P < 0.001) remained independent predictors of ICAS+LVO. The area under the curve of D-dimer, collaterals, and combination for identification of ICAS+LVO was 0.82, 0.85, and 0.92, respectively.

CONCLUSION

Low early plasma D-dimer levels are a significant and independent predictor of ICAS+LVO, and predictive value strengthens when in a combined model using D-dimer and collateral grading.

Characteristics of Ischemic Versus Hemorrhagic Stroke in Patients Receiving Oral Anticoagulants: Results of the PASTA Study

Objective Limited data exist regarding the comparative detailed clinical characteristics of patients with ischemic stroke (IS)/transient ischemic attack (TIA) and intracerebral hemorrhage (ICH) receiving oral anticoagulants (OACs). Methods The prospective analysis of stroke patients taking oral anticoagulants (PASTA) registry, a multicenter registry of 1,043 stroke patients receiving OACs [vitamin K antagonists (VKAs) or non-vitamin K antagonist oral anticoagulant (NOACs)] across 25 medical institutions throughout Japan, was used. Univariate and multivariable analyses were used to analyze differences in clinical characteristics between IS/TIA and ICH patients with atrial fibrillation (AF) who were registered in the PASTA registry. Results There was no significant differences in cardiovascular risk factors, such as hypertension, diabetes mellitus, dyslipidemia, smoking, or alcohol consumption (all p>0.05), between IS/TIA and ICH among both NOAC and VKA users. Cerebral microbleeds (CMBs) [odds ratio (OR), 4.77; p<0.0001] were independently associated with ICH, and high brain natriuretic peptide/N-terminal pro B-type natriuretic peptide levels (OR, 1.89; p=0.0390) were independently associated with IS/TIA among NOAC users. A history of ICH (OR, 13.59; p=0.0279) and the high prothrombin time-international normalized ratio (PT-INR) (OR, 1.17; p<0.0001) were independently associated with ICH, and a history of IS/TIA (OR, 3.37; 95% CI, 1.34-8.49; p=0.0101) and high D-dimer levels (OR, 2.47; 95% CI, 1.05-5.82; p=0.0377) were independently associated with IS/TIA among VKA users. Conclusion The presence of CMBs, a history of stroke, natriuretic peptide and D-dimer levels, and PT-INR may be useful for risk stratification of either IS/TIA or ICH development in patients with AF receiving OACs.

Prediction of recurrent stroke among ischemic stroke patients with atrial fibrillation: Development and validation of a risk score model

BACKGROUND

There is currently no validated risk prediction model for recurrent events among patients with acute ischemic stroke (AIS) and atrial fibrillation (AF). Considering that the application of conventional risk scores has contextual limitations, new strategies are needed to develop such a model. Here, we set out to develop and validate a comprehensive risk prediction model for stroke recurrence in AIS patients with AF.

METHODS

AIS patients with AF were collected from multicenter registries in South Korea and Japan. A developmental dataset was constructed with 5648 registered cases from both countries for the period 2011‒2014. An external validation dataset was also created, consisting of Korean AIS subjects with AF registered between 2015 and 2018. Event outcomes were collected during 1 year after the index stroke. A multivariable prediction model was developed using the Fine-Gray subdistribution hazard model with non-stroke mortality as a competing risk. The model incorporated 21 clinical variables and was further validated, calibrated, and revised using the external validation dataset.

RESULTS

The developmental dataset consisted of 4483 Korean and 1165 Japanese patients (mean age, 74.3 ± 10.2 years; male 53%); 338 patients (6%) had recurrent stroke and 903 (16%) died. The clinical profiles of the external validation set (n = 3668) were comparable to those of the developmental dataset. The c-statistics of the final model was 0.68 (95% confidence interval, 0.66 ‒0.71). The developed prediction model did not show better discriminative ability for predicting stroke recurrence than the conventional risk prediction tools (CHADS2, CHA2DS2-VASc, and ATRIA).

CONCLUSIONS

Neither conventional risk stratification tools nor our newly developed comprehensive prediction model using available clinical factors seemed to be suitable for identifying patients at high risk of recurrent ischemic stroke among AIS patients with AF in this modern direct oral anticoagulant era. Detailed individual information, including imaging, may be warranted to build a more robust and precise risk prediction model for stroke survivors with AF.

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.

d-dimer Level as a Predictor of Recurrent Stroke in Patients With Embolic Stroke of Undetermined Source

[Figure: see text].

Clinical Characteristics of Stroke with COVID-19: A Systematic Review and Meta-Analysis

BACKGROUND

The coronavirus disease 2019 (COVID-19) potentially increases the risk of thromboembolism and stroke. Numerous case reports and retrospective cohort studies have been published with mixed characteristics of COVID-19 patients with stroke regarding age, comorbidities, treatment, and outcome. We aimed to depict the frequency and clinical characteristics of COVID-19 patients with stroke.

METHODS

PubMed and EMBASE were searched on June 10, 2020, to investigate COVID-19 and stroke through retrospective cross-sectional studies, case series/reports according to PRISMA guidelines. Study-specific estimates were combined using one-group meta-analysis in a random-effects model.

RESULTS

10 retrospective cohort studies and 16 case series/reports were identified including 183 patients with COVID-19 and stroke. The frequency of detected stroke in hospitalized COVID-19 patients was 1.1% ([95% confidential interval (CI)]: [0.6-1.6], I2 = 62.9%). Mean age was 66.6 ([58.4-74.9], I2 = 95.1%), 65.6% was male (61/93 patients). Mean days from symptom onset of COVID-19 to stroke was 8.0 ([4.1-11.9], p< 0.001, I2 = 93.1%). D-dimer was 3.3 μg/mL ([1.7-4.9], I2 = 86.3%), and cryptogenic stroke was most common as etiology at 50.7% ([31.0-70.4] I2 = 64.1%, 39/71patients). Case fatality rate was 44.2% ([27.9-60.5], I2 = 66.7%, 40/100 patients).

CONCLUSIONS

This systematic review assessed the frequency and clinical characteristics of stroke in COVID-19 patients. The frequency of detected stroke in hospitalized COVID-19 patients was 1.1% and associated with older age and stroke risk factors. Frequent cryptogenic stroke and elevated d-dimer level support increased risk of thromboembolism in COVID-19 associated with high mortality. Further study is needed to elucidate the pathophysiology and prognosis of stroke in COVID-19 to achieve most effective care for this population.

Acute Ischemic Stroke in COVID-19: A Case-Based Systematic Review

Corona virus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus2 (SARS-CoV-2) is recognized as a global pandemic by WHO 2020 with 5,934 936 infections, 367,166 deaths and affecting over 200 countries as of 30th May 2020. Acute Ischemic Stroke (AIS) in brain is also emerging as an important neurovascular/neurological complication of COVID-19, associated with extreme immune responses leading to dysregulated coagulation system and generalized thrombo-embolic status and increased risk of AIS especially among usually less vulnerable younger adults in this cohort. Thus, in early June 2020, we aimed to review the clinical data on all published cases of COVID-19 and concomitant AIS, with a view to understanding the pertinent clinical, laboratory and imaging features. The neutrophil-lymphocyte ratio (NLR) at time of hospital admission for COVID infection correlates positively with the duration of time before onset of clinical features of AIS. Higher NLR, C-Reactive protein, serum ferritin, D-dimer and fibrinogen levels are associated with poor prognosis of AIS in COVID-19 with 75% of patients dying or being severely disabled at present. Currently it is too early to comment on the long-term outcomes for survivors.