Silent Brain Infarction Research Articles

Echocardiographic signs of atrial cardiopathy and MRI-detected silent brain infarcts in a middle-aged cohort: the Akershus Cardiac Examination 1950 Study

Abstract Background Atrial fibrillation (AF) is linked to clinical stroke and silent brain infarction (SBI). In the majority of AF patients, there exists a recognized form of atrial cardiopathy, and it is suggested that atrial cardiopathy, even in the absence of AF, may serve as a risk factor for stroke. However, existing evidence is limited, and it remains unclear whether atrial cardiopathy indeed poses a risk for stroke and SBI. Purpose We aimed to investigate the association between echocardiographic signs of atrial cardiopathy and the detection of SBI through magnetic resonance imaging (MRI) in a middle-aged cohort from the general population. Methods In the prospective Akershus Cardiac Examination (ACE) 1950 Study conducted within the general population in Norway, cardiovascular risk assessment including transthoracic echocardiography, was undertaken at study inclusion between 2012 and 2015. We assessed body surface area-indexed left atrial (LA) maximum and minimum volume, as well as LA reservoir and contractile strain. Subsequently, brain MRI was conducted in a subset of the cohort between 2017 and 2023. SBI was defined as presence of neuroimaging sign of infarcts, including lacunes, in individuals without a history of stroke. Logistic regression analyses were performed to explore the associations between echocardiographic measures of atrial cardiopathy and SBI on MRI, adjusting for sex, age, hypertension, and diabetes. Results A total of 397 out of 3706 (10.7%) participants in the ACE 1950 study underwent MRI examination and were included in this analysis. At the time of MRI, the mean age was 70.0±2.2 years, with 157 (40%) women, 248 (62%) with hypertension, and 36 (9%) with diabetes at study inclusion. SBI was present in 51 (13%), of which only 1 (2%) had known AF. After excluding 18 participants with pre-existing AF, no significant difference were observed in LA volumes or LA strain between participants with or without SBI (Figure 1). In unadjusted and adjusted logistic regression analyses, neither LA volume nor LA strain were associated with SBI (Table 1). Conclusion Echocardiographic signs of atrial cardiopathy were not associated with silent brain infarcts in a middle-aged cohort from the general population.

Current Strategies for Atrial Fibrillation Prevention and Management: Taming the Commonest Cardiac Arrhythmia.

Atrial fibrillation (AF) is the commonest cardiac arrhythmia, constituting a major cause of morbidity and mortality, with an age-dependent incidence and prevalence ranging from 1-2% in the general population to ~10% in persons aged >60 years. The global prevalence of AF is rapidly increasing, mostly due to the aging population. If not properly and timely managed, this arrhythmia adversely affects left ventricular function, increases the risk of stroke five-fold, impairs quality of life, and shortens longevity. There is a genetic, hence non-modifiable, predisposition to the arrhythmia, while several life-style and cardiometabolic inciting factors, such as hypertension, heart failure, coronary disease, metabolic syndrome, alcohol use, and thyroid disorders, can be addressed, attesting to the importance of a holistic approach to its management. Thromboembolism is a serious consequence of AF, which could lead to a disabling stroke or have a lethal outcome. The risk of a thromboembolic complication can be estimated as based on a scoring system that takes into consideration the patient's age, previous thromboembolic events, and clinical comorbidities. In addition, rapid AF could affect cardiac performance, leading to an elusive type of arrhythmia-induced cardiomyopathy and heart failure with grave consequences if undetected and untreated. Furthermore, AF may cause silent brain infarcts and/or its hemodynamic perturbations can account for a type of dementia that needs to be taken into account, emphasizing the need for AF screening and prevention strategies. All these issues are herein detailed, the causes of the arrhythmia are tabulated, and an algorithm illustrates our current approach to its management.

Obstructive sleep apnea and cerebral small vessel disease in community-based older people: an aspirin in reducing events in the elderly imaging substudy

Abstract Study Objectives Obstructive sleep apnea (OSA) may increase the risk of dementia. A potential pathway for this risk is through cerebral small vessel disease (CSVD). In the context of an existing randomized trial of aspirin for primary prevention, we aimed to investigate OSA’s impact on CSVD imaging measures and explore whether aspirin effects these measures over 3 years that differ in the presence or absence of OSA. Methods A substudy of the aspirin in reducing events in the elderly (ASPREE) randomized placebo-controlled trial of low-dose aspirin. Community-dwelling participants aged 70 years and above, without cognitive impairment, cardiovascular disease, or known OSA completed an unattended limited-channel sleep study that calculated the oxygen desaturation index and apnea–hypopnea index. At baseline and 3 years later, volumes of white matter hyperintensities (WMH) and silent brain infarctions (SBI) were measured on 1.5 Tesla brain magnetic resonance imaging, and retinal vessel calibers were calculated from retinal vascular imaging. Results Mild and moderate/severe OSA was detected in 48.9% and 29.9%, respectively, of the 311 participants, who had a mean age of 73.7 years (SD 3.4 years), 38.6% female. OSA of any severity was not associated with WMH volumes, SBI, nor retinal vessel calibers at baseline, nor with change in these measures in the 277 participants with repeated measures acquired after 3 years. OSA of any severity did not interact with aspirin on change in these measures over 3 years. Conclusions In healthy older adults undiagnosed OSA was not associated with retinal vascular calibers and neuroimaging measures of CSVD. Clinical Trial Information ASPREE trial has registration with the International Standard Randomized Controlled Trial Number (ISRCTN) www.isrctn.com, ISRCTN83772183 and with www.clinicaltrials.gov, NCT01038583. SNORE-ASA has registration with the Australian New Zealand Clinical Trials Registry (ANZCTR) at www.anzctr.org.au, ACTRN12612000891820.

Intima-Media Thickness in the Carotid Bifurcation is Related to Silent Brain Infarction: A Cross-Sectional Study.

Carotid intima-media thickness (IMT) measurement is used to assess subclinical atherosclerosis. We aimed to examine the association between the maximum IMT by location and the occurrence of silent brain infarction (SBI). Overall, 280 Japanese individuals (92 females, 52.6±5 years old) underwent a medical check-up at our hospital in Tokyo in 2015. Carotid IMT was measured at each site on ultrasound images (common carotid artery [CCA], internal carotid artery, or bifurcation). The risk factors for arterial dysfunction were evaluated. SBI was assessed using magnetic resonance imaging (MRI). The cross-sectional relationship between carotid maximum IMT and SBI was evaluated. Of the 280 individuals, 18 (6.4%) were diagnosed with SBI on MRI. The mean age of the SBI(-) and SBI(+) groups was 51.9±10.6 and 63.6±18.6 years, respectively. The correlation coefficients between the carotid maximum IMT at each location were very weak (correlation coefficient range: 0.180-0.253). The percentage of participants with SBI increased significantly with increasing maximum CCA and bIMT values. After adjusting for confounders, SBI was found to be significantly associated with the maximum bIMT (per 0.1-mm increase) (adjusted odds ratio [aOR], 1.10; 95% confidence interval [CI]: 1.03-1.17). When bIMT was categorized according to three groups (＜1.0 mm, 1.0-＜2.0 mm, and ≥ 2.0 mm), a significant SBI risk was also observed with an increase by each category of bIMT (aOR: 3.96, 95% CI: 1.63-9.52, P=0.002). The maximum bIMT was found to be the main determinant of SBI. A significant SBI risk was associated with an increase in each category of the maximum bIMT. Therefore, the maximum bIMT might be a useful predictor of future stroke in Japanese stroke-free medical check-up participants.

Elective direct current cardioversion of atrial fibrillation - silent brain infarction and health related quality of life.

Atrial fibrillation (AF) increases the risk for stroke, dementia and impaired health related quality of life (HRQL). Elective direct current cardioversion (ECV) is often used to restore sinus rhythm, but is associated with thromboembolism. While larger strokes usually produce symptoms, subclinical ones may go unrecognized and may cause cognitive and functional decline over time. In the current study, we sought to evaluate the effects of ECV on silent brain infarctions and HRQL in patients with AF. Patients with AF (n=46) underwent brain magnetic resonance imaging (MRI) and HRQL assessment using the EuroQL-5D5L questionnaire before and after ECV. Implantable loop recorders (ILR) were used to observe the rate of early AF recurrences within the first thirty days. All patients were treated with anticoagulants according to guidelines. The primary endpoint was silent brain infarction assessed by brain MRI within the first two weeks after ECV. Secondary endpoints were the change in HRQL and its association with AF recurrence at follow-up and by ILR recordings. New silent brain infarction after ECV was detected in one patient. At follow-up visit after 19.1 days AF recurrence was detected by 12-lead ECG in 13 patients (28.3 %), whereas 27 patients (58.7 %) had AF recurrence recorded by ILR within the first thirty days after ECV. European Heart Rhythm Association (EHRA) symptom score and the EuroQL-5d5L score were improved after ECV. Silent brain infarctions may occur after ECV despite anticoagulation treatment. Early AF recurrence is frequent. ECV positively affects HRQL mainly in those patients with sustained sinus rhythm at follow-up.

Cardiac stasis imaging, stroke, and silent brain infarcts in patients with nonischemic dilated cardiomyopathy.

Cardioembolic stroke is one of the most devastating complications of nonischemic dilated cardiomyopathy (NIDCM). However, in clinical trials of primary prevention, the benefits of anticoagulation are hampered by the risk of bleeding. Indices of cardiac blood stasis may account for the risk of stroke and be useful to individualize primary prevention treatments. We performed a cross-sectional study in patients with NIDCM and no history of atrial fibrillation (AF) from two sources: 1) a prospective enrollment of unselected patients with left ventricular (LV) ejection fraction <45% and 2) a retrospective identification of patients with a history of previous cardioembolic neurological event. The primary end point integrated a history of ischemic stroke or the presence intraventricular thrombus, or a silent brain infarction (SBI) by imaging. From echocardiography, we calculated blood flow inside the LV, its residence time (TR) maps, and its derived stasis indices. Of the 89 recruited patients, 18 showed a positive end point, 9 had a history of stroke or transient ischemic attack (TIA) and 9 were diagnosed with SBIs in the brain imaging. Averaged TR, [Formula: see text] performed well to identify the primary end point [AUC (95% CI) = 0.75 (0.61-0.89), P = 0.001]. When accounting only for identifying a history of stroke or TIA, AUC for [Formula: see text] was 0.92 (0.85-1.00) with odds ratio = 7.2 (2.3-22.3) per cycle, P < 0.001. These results suggest that in patients with NIDCM in sinus rhythm, stasis imaging derived from echocardiography may account for the burden of stroke.NEW & NOTEWORTHY Patients with nonischemic dilated cardiomyopathy (NIDCM) are at higher risk of stroke than their age-matched population. However, the risk of bleeding neutralizes the benefit of preventive oral anticoagulation. In this work, we show that in patients in sinus rhythm, the burden of stroke is related to intraventricular stasis metrics derived from echocardiography. Therefore, stasis metrics may be useful to personalize primary prevention anticoagulation in these patients.

Impact of repositioning on brain injury following transcatheter aortic valve replacement with a self-expanding valve

Repositionable self-expanding valves allow for repositioning during deployment to achieve optimal valve placement. However, the risk of brain injury associated with repositioning, as detected by diffusion-weighted magnetic resonance imaging (DW-MRI), is unknown. Consecutive patients undergoing transcatheter aortic valve replacement (TAVR) with repositionable self-expanding valves and receiving DW-MRI before and within 7 days post-TAVR procedure were included. The primary outcomes were incidence, number, total volume, and volume per lesion of the cerebral ischemic lesion in DW-MRI after TAVR. Univariate and multivariate logistic regression assessed the association between repositioning and bigger total lesion volume (> 1 cm3 or > 0.5 cm3). Negative binomial regressions were performed to explore the association between repositioning and number of lesions. A propensity score matching was performed to adjust the potential confounders. Moreover, inverse probability of treatment weighted regression model with nonstabilized weights was used as sensitivity analysis. Among 243 included patients, repositioning was performed in 116 (47.7%) patients. The incidence of overt stroke (1.7% vs. 1.6%, p = 0.927) and silent stroke (86.2% vs. 85.8%, p = 0.932) were comparable between two groups. However, the number of new lesions (5.0 [2.0–9.0] vs. 3.0 [2.0–6.0], p = 0.048), and total lesion volume (275.0 [90.0–947.5] mm3 vs. 180.0 [50.0–440.0] mm3, p = 0.022) were significantly higher in the repositioned group. Moreover, the proportion of patients with lesion size greater than 0.5 cm3 was higher in the repositioned group (37.9% vs. 22.0%, p = 0.007). The similar results were observed after propensity score matching. In both multivariate regression model and sensitivity analysis, the repositioning was the independent predictor of number of lesions and bigger total lesion volume after TAVR. The utilization of the repositioning feature may increase the number and volume of silent brain infarcts in DW-MRI in patients who underwent TAVR. (Transcatheter Aortic Valve Replacement Single Center Registry in Chinese Population [TORCH]; NCT02803294)

Role of Cardiac Biomarkers in Stroke and Cognitive Impairment.

This topical review assesses the growing role of cardiac biomarkers beyond cardiovascular health and focuses on their importance in stroke and dementia. The first part describes blood-based cardiac biomarkers in patients with stroke and highlights applications in the setting of early diagnosis, poststroke complications, outcome prediction as well as secondary prevention. Among other applications, natriuretic peptides can be helpful in differentiating stroke subtypes. They are also currently being investigated to guide prolonged ECG monitoring and secondary prevention in patients with stroke. Elevated cardiac troponin after ischemic stroke can provide information about various poststroke complications recently termed the stroke-heart syndrome. The second part focuses on the role of cardiac biomarkers in vascular cognitive impairment and dementia, emphasizing their association with structural brain lesions. These lesions such as silent brain infarcts and white matter hyperintensities often co-occur with cardiac disease and may be important mediators between cardiovascular disease and subsequent cognitive decline. ECG and echocardiogram measurements, in addition to blood-based biomarkers, show consistent associations with vascular brain changes and incident dementia, suggesting a role in indicating risk for cognitive decline. Together, the current evidence suggests that cardiac blood-based, electrophysiological, and imaging biomarkers can be used to better understand the heart and brain connection in the setting of not only stroke but also dementia.

La imagen de estasis predice el riesgo de eventos cardioembólicos tras el infarto agudo de miocardio: el estudio ISBITAMI

Introduction and objectivesIn the setting of ST-segment elevation myocardial infarction (STEMI), imaging-based biomarkers could be useful for guiding oral anticoagulation to prevent cardioembolism. Our objective was to test the efficacy of intraventricular blood stasis imaging for predicting a composite primary endpoint of cardioembolic risk during the first 6 months after STEMI. MethodsWe designed a prospective clinical study, Imaging Silent Brain Infarct in Acute Myocardial Infarction (ISBITAMI), including patients with a first STEMI, an ejection fraction ≤ 45% and without atrial fibrillation to assess the performance of stasis metrics to predict cardioembolism. Patients underwent ultrasound-based stasis imaging at enrollment followed by heart and brain magnetic resonance at 1-week and 6-month visits. From the stasis maps, we calculated the average residence time, RT, of blood inside the left ventricle and assessed its performance to predict the primary endpoint. The longitudinal strain of the 4 apical segments was quantified by speckle tracking. ResultsA total of 66 patients were assigned to the primary endpoint. Of them, 17 patients had 1 or more events: 3 strokes, 5 silent brain infarctions, and 13 mural thromboses. No systemic embolisms were observed. RT (OR, 3.73; 95%CI, 1.75-7.9; P<.001) and apical strain (OR, 1.47; 95%CI, 1.13-1.92; P=.004) showed complementary prognostic value. The bivariate model showed a c-index=0.86 (95%CI, 0.73-0.95), a negative predictive value of 1.00 (95%CI, 0.94-1.00), and positive predictive value of 0.45 (95%CI, 0.37-0.77). The results were confirmed in a multiple imputation sensitivity analysis. Conventional ultrasound-based metrics were of limited predictive value. ConclusionsIn patients with STEMI and left ventricular systolic dysfunction in sinus rhythm, the risk of cardioembolism may be assessed by echocardiography by combining stasis and strain imaging. Registered at ClinicalTrials.gov (NCT02917213).

Correlation of Silent Brain Infarction with the Metabolic Abnormality of CKD Stage 3-5 (non-dialytic) Patients

Background: Silent brain infarction (SBI) poses a significant yet often undetected risk in chronic kidney disease (CKD) patients, predisposing them to symptomatic stroke, dementia, and neurological mortality. Despite its implications, the association between SBI and CKD remains elusive, necessitating further exploration to elucidate potential predictive factors. Objective: This cross-sectional study investigated the relationship between SBI and metabolic abnormalities prevalent in CKD stages 3-5 (non-dialytic) patients. Methods: Conducted at the Department of Nephrology, Dhaka Medical College Hospital, Dhaka, from September 2018 to March 2020, the study enrolled 115 participants. Group I comprised 85 CKD stage 3-5 (non-dialytic) patients without neurological symptoms, while Group II comprised 30 healthy controls. Glomerular filtration rate (GFR) was estimated using the Modification of Diet in Renal Diseases equation. Magnetic resonance imaging (MRI) was performed on all subjects. Statistical analysis utilized SPSS-26. Results: The rate of Silent Brain Infarction is 52.9% in CKD patients. SBI was found in 45(52.9%) patients in group I and 4(13.3%) in group II. The differences were statistically significant (p&lt;0.05). Glomerulonephritis (45.9%) was the leading cause of CKD among the study patients. Most of the patients with Hypertensive Nephrosclerosis (76.9%) had SBI, which indirectly showed its strong association. As the CKD stages progressed, the SBI rate also increased (stage-3:8.9%; stage-4:35.6%; stage-5ND:55.6%). In a multivariate logistic regression analysis, CKD had an independent relationship with SBI along with serum phosphate level and serum parathyroid hormone level (CKD had Odds ratio (OR)=1.847 (95.0% CI 0.064 to 53.319), serum PO4 had OR=0.958 (95.0% CI 0.885 to 1.038) and serum PTH had OR=0.996 (95.0% CI 0.993 to 1.000). Spearman rank correlation coefficient test showed a positive correlation between the occurrence of SBI and serum PO4 level (r=0.416; p=0.001) and serum PTH level (r= 0.405; p=0.001) separately. Conclusions: The high prevalence of SBI in CKD stage 3-5 (non-dialytic) patients underscores its clinical significance. Serum phosphate and parathyroid hormone levels positively correlate with SBI occurrence, highlighting their potential as predictive markers. Understanding these associations can inform risk stratification and guide targeted interventions in CKD management.

Distal normal vessel diameter might be associated with silent brain infarcts after stenting for symptomatic carotid stenosis

BackgroundCarotid artery stenting (CAS) has been the standard treatment for carotid stenosis because it is less invasive; however, the risk of periprocedural thromboembolism is high. We investigated the predictors for silent brain infarcts (SBIs), focusing on embolic protection in CAS. MethodsThis study was single-center retrospective study, and we obtained baseline demographics and clinical, laboratory, and periprocedural variables of patients who underwent CAS. Also, methods used for embolic protection (no EPD, distal EPD, or proximal balloon guiding catheter) during CAS were obtained. Distal normal vessel diameter was defined as the diameter of cervical internal carotid artery where the artery wall becomes parallel. Diffusion-weighted imaging was performed before and after procedure to detect SBIs. The primary outcome was stented territory SBIs, and the secondary outcomes were any territories SBIs and stented territory SBIs in cases with EPD. ResultsA total of 196 CAS procedures with mean age 69.1 ± 9.9 years were included. After CAS, stented territory SBIs occurred in 53 (27.0 %) cases and any territories SBIs in 60 (30.6 %) cases. Univariable analyses revealed that distal normal vessel diameter (odds ratio = 1.71, 95 % confidence interval = 1.20–2.43, P = 0.003) was associated with the occurrence of stented territory SBIs after CAS. After adjusting for potential variables, larger distal normal vessel diameter (1.61 [1.10–2.36], P = 0.014) increased the occurrence of SBIs after CAS. Consistent results were obtained when the outcome was any territories SBIs or stented territory SBIs in cases with EPD. ConclusionsDistal normal vessel diameter was a predictor for the occurrence of SBI after CAS. The passable pore size of EPDs may vary depending on vessel diameter, and may impact the occurrence of SBIs.

Silent Brain Infarction; Risk Factors and Effect on Outcome of Acute Ischemic Stroke

Silent Brain Infarction; Risk Factors and Effect on Outcome of Acute Ischemic Stroke

Stasis imaging predicts the risk of cardioembolic events related to acute myocardial infarction: the ISBITAMI study

Introduction and objectivesIn the setting of ST-segment elevation myocardial infarction (STEMI), imaging-based biomarkers could be useful for guiding oral anticoagulation to prevent cardioembolism. Our objective was to test the efficacy of intraventricular blood stasis imaging for predicting a composite primary endpoint of cardioembolic risk during the first 6 months after STEMI. MethodsWe designed a prospective clinical study, Imaging Silent Brain Infarct in Acute Myocardial Infarction (ISBITAMI), including patients with a first STEMI, an ejection fraction ≤ 45% and without atrial fibrillation to assess the performance of stasis metrics to predict cardioembolism. Patients underwent ultrasound-based stasis imaging at enrollment followed by heart and brain magnetic resonance at 1-week and 6-month visits. From the stasis maps, we calculated the average residence time, RT, of blood inside the left ventricle and assessed its performance to predict the primary endpoint. The longitudinal strain of the 4 apical segments was quantified by speckle tracking. ResultsA total of 66 patients were assigned to the primary endpoint. Of them, 17 patients had 1 or more events: 3 strokes, 5 silent brain infarctions, and 13 mural thromboses. No systemic embolisms were observed. RT (OR, 3.73; 95%CI, 1.75-7.9; P<.001) and apical strain (OR, 1.47; 95%CI, 1.13-1.92; P=.004) showed complementary prognostic value. The bivariate model showed a c-index=0.86 (95%CI, 0.73-0.95), a negative predictive value of 1.00 (95%CI, 0.94-1.00), and positive predictive value of 0.45 (95%CI, 0.37-0.77). The results were confirmed in a multiple imputation sensitivity analysis. Conventional ultrasound-based metrics were of limited predictive value. ConclusionsIn patients with STEMI and left ventricular systolic dysfunction in sinus rhythm, the risk of cardioembolism may be assessed by echocardiography by combining stasis and strain imaging. Registered at ClinicalTrials.gov (NCT02917213).

Covert Cerebrovascular Changes in People With Heart Disease: A Systematic Review and Meta-Analysis.

To determine the prevalence of silent brain infarction (SBI) and cerebral small vessel disease (CSVD) in adults with atrial fibrillation (AF), coronary artery disease, heart failure or cardiomyopathy, heart valve disease, and patent foramen ovale (PFO), with comparisons between those with and without recent stroke and an exploration of associations between heart disease and SBI/CSVD. Medline, Embase, and Cochrane Library were systematically searched for hospital-based or community-based studies reporting SBI/CSVD in people with heart disease. Data were extracted from eligible studies. Outcomes were SBI (primary) and individual CSVD subtypes. Summary prevalence (95% confidence intervals [CIs]) were obtained using random-effects meta-analysis. Pooled prevalence ratios (PRs) (95% CI) were calculated to compare those with heart disease with available control participants without heart disease from studies. A total of 221 observational studies were included. In those with AF, the prevalence was 36% (31%-41%) for SBI (70 studies, N = 13,589), 25% (19%-31%) for lacune (26 studies, N = 7,172), 62% (49%-74%) for white matter hyperintensity/hypoattenuation (WMH) (34 studies, N = 7,229), and 27% (24%-30%) for microbleed (44 studies, N = 13,654). Stratification by studies where participants with recent stroke were recruited identified no differences in the prevalence of SBI across subgroups (phomogeneity = 0.495). Results were comparable across participants with different heart diseases except for those with PFO, in whom there was a lower prevalence of SBI [21% (13%-30%), 11 studies, N = 1,053] and CSVD. Meta-regressions after pooling those with any heart disease identified associations of increased (study level) age and hypertensives with more SBIs and WMH (pregression <0.05). There was no evidence of a difference in the prevalence of microbleed between those with and without heart disease (PR [95% CI] 1.1 [0.7-1.7]), but a difference was seen in the prevalence of SBI and WMH (PR [95% CI] 2.3 [1.6-3.1] and 1.7 [1.1-2.6], respectively). People with heart disease have a high prevalence of SBI (and CSVD), which is similar in those with vs without recent stroke. More research is required to assess causal links and implications for management. PROSPERO CRD42022378272 (crd.york.ac.uk/PROSPERO/).

Prospective Study of Extracellular Vesicles in Plasma as Potential Biomarkers for Silent Brain Infarcts (P10-4.013)

Prospective Study of Extracellular Vesicles in Plasma as Potential Biomarkers for Silent Brain Infarcts (P10-4.013)

MRI Investigation of the Association of Left Atrial and Left Atrial Appendage Hemodynamics with Silent Brain Infarction.

Left atrial (LA) myopathy is thought to be associated with silent brain infarctions (SBI) through changes in blood flow hemodynamics leading to thrombogenesis. 4D-flow MRI enables in-vivo hemodynamic quantification in the left atrium (LA) and LA appendage (LAA). To determine whether LA and LAA hemodynamic and volumetric parameters are associated with SBI. Prospective observational study. A single-site cohort of 125 Participants of the multiethnic study of atherosclerosis (MESA), mean age: 72.3 ± 7.2 years, 56 men. 1.5T. Cardiac MRI: Cine balanced steady state free precession (bSSFP) and 4D-flow sequences. Brain MRI: T1- and T2-weighted SE and FLAIR. Presence of SBI was determined from brain MRI by neuroradiologists according to routine diagnostic criteria in all participants without a history of stroke based on the MESA database. Minimum and maximum LA volumes and ejection fraction were calculated from bSSFP data. Blood stasis (% of voxels <10 cm/sec) and peak velocity (cm/sec) in the LA and LAA were assessed by a radiologist using an established 4D-flow workflow. Student's t test, Mann-Whitney U test, one-way ANOVA, chi-square test. Multivariable stepwise logistic regression with automatic forward and backward selection. Significance level P < 0.05. 26 (20.8%) had at least one SBI. After Bonferroni correction, participants with SBI were significantly older and had significantly lower peak velocities in the LAA. In multivariable analyses, age (per 10-years) (odds ratio (OR) = 1.99 (95% confidence interval (CI): 1.30-3.04)) and LAA peak velocity (per cm/sec) (OR = 0.87 (95% CI: 0.81-0.93)) were significantly associated with SBI. Older age and lower LAA peak velocity were associated with SBI in multivariable analyses whereas volumetric-based measures from cardiac MRI or cardiovascular risk factors were not. Cardiac 4D-flow MRI showed potential to serve as a novel imaging marker for SBI. 3 TECHNICAL EFFICACY: Stage 2.

Abstract WMP70: Neuroradiological Markers of Cerebral Small Vessel Disease in Adults With Congenital Heart Disease After Fontan Surgery

Introduction: Fontan surgery performed during childhood enhances the lifespan and quality of life of patients with critical congenital heart disease. Post-Fontan circulation may impact function in multiple organ systems, but its long term effects on the brain microvasculature are not well characterized. We investigated brain MRI markers of cerebral small vessel disease (SVD) after exposure to Fontan circulation. Methods: We reviewed medical records and MRI images of 34 adults followed in an academic medical center after Fontan surgery, who had brain MRI for any reason from 08/01/1995-03/01/2022. We characterized Fontan physiological stage (a standardized measure of disease severity) at time of MRI, and identified SVD markers, including deep silent brain infarcts, small perivascular spaces in the basal ganglia, microhemorrhages, and white matter hyperintensities. We calculated SVD scores using a standardized scale of 0-4, where scores of ≥2 indicate moderate to severe SVD. We created ordinal logistic regression models to test the association between physiological stage and SVD score. Results: Characteristics of the patients are summarized in the Table, and distribution of SVD scores in the Figure. Adjusting for age at MRI, there was no association between physiological stage of disease and higher SVD score. Conclusion: In our sample of 34 young adult patients with long term exposure to Fontan circulation, the majority had evidence of moderate to severe SVD, which was not predicted by physiological stage of disease at time of MRI. Exposure to Fontan circulation may be associated with early onset of cerebral SVD, suggesting increased long term risk of stroke and dementia.

Correlation of silent brain infarcts and leukoaraiosis in middle-aged ischemic stroke patients: a retrospective study.

Cerebrovascular diseases of the brain are usually defined by transient ischemic attacks and strokes. However, they can also cause brain injuries without neurological events. Silent brain infarcts (SBI) and leukoaraiosis are symptoms of both vascular and neurological abnormalities. This study aims to investigate the association between SBI, leukoaraiosis, and middle-aged patients with ischemic stroke. A single-center retrospective study of 50 middle-aged, ischemic stroke patients were studied from November 2022 and May 2023. The patients were divided into two groups based on the presence or absence of leukoaraiosis. History taking, physical examination, brain CT scan, and MRI were all part of the diagnostic process. Metabolic syndrome (MetS) was also assessed through various factors. The statistical analysis included descriptive statistics, logistic regression analysis, and chi-square test. Out of the cohort comprising 50 patients, characterized by a mean age of 52.26 years (SD 5.29), 32 were male, constituting 64% of the sample. Among these patients, 26 individuals exhibited leukoaraiosis, with 17 of them (65.4%) also presenting with SBI. Moreover, within this cohort, 22 patients were diagnosed with MetS, representing 84.6% of those affected. The Multivariate logistic regression analysis showed a strong and independent association between leukoaraiosis and SBI. Individuals with leukoaraiosis were nearly five times more likely to have SBI compared to those without leukoaraiosis. The study highlights leukoaraiosis as a significant risk factor for SBI, alongside MetS. Advanced imaging techniques have facilitated their detection, revealing a higher prevalence among stroke patients, particularly associated with age and hypertension. Further research is needed to fully understand their complex relationship and develop better management strategies for cerebrovascular diseases, ultimately improving patient outcomes.

Performance assessment of an electrostatic filter-diverter stent cerebrovascular protection device. Is it possible not to use anticoagulants in atrial fibrilation elderly patients?

Stroke is the second leading cause of death worldwide. Nearly two-thirds of strokes are produced by cardioembolisms, and half of cardioembolic strokes are triggered by Atrial Fibrillation (AF), the most common type of arrhythmia. A more recent cause of cardioembolisms is Transcatheter Aortic Valve Replacements (TAVRs), which may onset post-procedural adverse events such as stroke and Silent Brain Infarcts (SBIs), for which no definitive treatment exists, and which will only get worse as TAVRs are implanted in younger and lower risk patients. It is well known that some specific characteristics of elderly patients may lower the safety and efficacy of anticoagulation therapy, making it a real urgency to find alternative therapies. We propose a device consisting of a strut structure placed at the base of the treated artery to model the potential risk of cerebral embolisms caused by dislodged debris of varying sizes. This work analyzes a design based on a patented medical device, intended to block cardioembolisms from entering the cerebrovascular system, with a particular focus on AF, and potentially TAVR patients. The study has been carried out in two stages. Both of them based on computational fluid dynamics (CFD) coupled with Lagrangian particle tracking method. The first stage of the work evaluates a variety of strut thicknesses and inter-strut spacings, contrasting with the device-free baseline geometry. The analysis is carried out by imposing flowrate waveforms characteristic of both healthy and AF patients. Boundary conditions are calibrated to reproduce physiological flowrates and pressures in a patient's aortic arch. In the second stage, the optimal geometric design from the first stage was employed, with the addition of lateral struts to prevent the filtration of particles and electronegatively charged strut surfaces, studying the effect of electrical forces on the clots if they are considered charged. Flowrate boundary conditions were used to emulate both healthy and AF conditions. Results from numerical simulations coming form the first stage indicate that the device blocks particles of sizes larger than the inter-strut spacing. It was found that lateral strut space had the highest impact on efficacy. Based on the results of the second stage, deploying the electronegatively charged device in all three aortic arch arteries, the number of particles entering these arteries was reduced on average by 62.6% and 51.2%, for the healthy and diseased models respectively, matching or surpassing current oral anticoagulant efficacy. In conclusion, the device demonstrated a two-fold mechanism for filtering emboli: while the smallest particles are deflected by electrostatic repulsion, avoiding microembolisms, which could lead to cognitive impairment, the largest ones are mechanically filtered since they cannot fit in between the struts, effectively blocking the full range of particle sizes analyzed in this study. The device presented in this manuscript offers an anticoagulant-free method to prevent stroke and SBIs, imperative given the growing population of AF and elderly patients.

Rationale and design of a randomized clinical trial evaluating the efficacy of mechanical neuroprotection in reducing the risk of silent brain infarcts associated with percutaneous left atrial appendage closure: study protocol for a LAAC-SBI trial

BackgroundLeft atrial appendage closure (LAAC) procedures prevent cardioembolic stroke in patients with atrial fibrillation who have contraindications to oral anticoagulant medications. However, these procedures carry certain risks of peri-procedural complications. One such complication is silent brain infarcts (SBI), which can lead to cognitive impairment and mood disturbances. The implementation of mechanical neuroprotection systems during LAAC procedures may reduce the risk of SBI and associated cognitive and mood disorders.MethodsThe LAAC-SBI trial is a prospective, multicenter, randomized, and double-blind interventional study. The study aims to enroll a total of 240 patients, with 120 patients allocated to each group. The study group will evaluate the use of the Sentinel CPS during LAAC, while the control group will undergo LAAC procedures without the Sentinel CPS. The primary endpoint of the study is the number of new SBIs or stroke foci detected by diffusion-weighted magnetic resonance imaging (DW MRI). Secondary endpoints include deterioration of cognitive function, development of dementia syndrome, and occurrence of depressive disorders. These endpoints will be assessed using questionnaire tools such as the Montreal Cognitive Assessment (MoCA), Trail Making Test (TMT), Controlled Oral Word Association Test (COWAT), and Hospital Anxiety and Depression Scale (HADS). The observational period for patients in the study is 2 years.DiscussionIf the study demonstrates a favorable outcome with reduced incidence of SBI and improved cognitive and mood outcomes in patients receiving cerebral protection devices during LAAC, it will have significant implications for clinical management standards. This would support the use of neuroprotection devices not only for LAAC but also in procedures such as atrial fibrillation ablation or transcatheter mitral valve interventions, where the risk of embolic events and subsequent brain injury may also be present.Trial registrationClinicalTrials.gov NCT05369195. Registration on 11.05.2022.