Heterogeneity of single small subcortical infarction can be reflected in lesion location

Clinical and Prognostic Characteristics of Acute BAD-Related Stroke: A Multicenter MRI-Based Prospective Study

BACKGROUND

Branch atheromatous disease (BAD)-related stroke has emerged as a meaningful subtype of ischemic stroke yet remained understudied. We aimed to investigate the demographic, clinical, therapeutic, and prognostic characteristics of BAD-related stroke.

METHODS

The BAD-study was a nationwide, multicenter, prospective, observational cohort study in 20 Chinese hospitals from June 2021 to June 2023, enrolling patients aged 18 to 80 years with BAD-related stroke within 72 hours of onset. Eligible single subcortical infarct in the territory of lenticulostriate artery and paramedian pontine artery was included. Clinical, laboratory, and treatment data were collected at baseline. The primary outcome was a proportion of good outcomes (modified Rankin Scale score, 0-2) at 90 days. Main secondary outcomes included early neurological deterioration (END), cerebrovascular event, major bleeding, and excellent outcome (modified Rankin Scale score, 0-1) during 90-day follow-up.

RESULTS

We finally enrolled 476 patients, with a median age of 60 (interquartile range, 53-68) years, and 70.2% were male. The median National Institutes of Health Stroke Scale score was 3 (interquartile range, 2-6) at enrollment. Involvement of the lenticulostriate artery was more common than the paramedian pontine artery (60.7% versus 39.3%). END occurred in 14.7% of patients, with a median time from onset of 38 (interquartile range, 22-62) hours. The rates of good and excellent outcomes were 86.5% and 72%, respectively. Its 90-day stroke recurrence rate was 1.9%. Acute-phase therapy (from onset to 7 days of enrollment) showed heterogeneity and was not associated with prognosis. Multivariable logistic regression analysis identified the National Institutes of Health Stroke Scale score ≥4 at admission and END as negative predictors and extracranial artery stenosis as a positive predictor of good outcomes. Age ≥60 years, National Institutes of Health Stroke Scale score ≥4 at admission, and END were negative predictors of excellent outcomes.

CONCLUSIONS

With distinct demographic, clinical, and prognostic characteristics, along with a high incidence of END and a low risk of stroke recurrence, BAD-related stroke could be categorized as a separate disease entity. Moreover, its acute-phase treatment strategies were undetermined, awaiting further high-quality studies.

Efficacy and safety of tirofiban in patients with acute branch atheromatous disease-related stroke (BRANT): a protocol for a randomised controlled trial

INTRODUCTION

Branch atheromatous disease (BAD)-related stroke is increasingly becoming a clinical entity and prone to early neurological deterioration (END) and poor prognosis. There are no effective regimens to reduce the disability caused by BAD-related stroke in acute phase. Recent studies have indicated the efficacy of tirofiban in acute ischaemic stroke; however, its efficacy has not been validated in patients with BAD-related stroke. Thus, we aim to test whether intravenous tirofiban initiated within 48 hours after the onset would improve the functional outcome in patients with acute BAD-related stroke, in comparison with the standard antiplatelet therapy based on the current guideline.

METHODS AND ANALYSIS

BRANT is a multicentre, randomised, open-label, blinded endpoint, parallel-controlled, phase III trial conducted in 21 hospitals in China. Participants aged 18-75 years with acute BAD-related stroke within 48 hours after the stroke onset are randomised in a 1:1 ratio to the tirofiban or control group. The treatment period is 48 hours in both groups. The primary outcome is the excellent functional outcome (modified Rankin Scale Score: 0-1) at 90 days. The secondary outcomes include END, major bleeding, stroke, death, functional status, serious adverse events and change in bleeding-related markers. Assuming the rates of the primary outcome to be 74% in the tirofiban group and 62% in the control group, a total of 516 participants are needed for 0.8 power (two-sided 0.05 alpha).

ETHICS AND DISSEMINATION

BRANT study has been approved by the Ethics Committee of the Peking Union Medical College Hospital (I-23PJ1242). Written informed consent is required for all the patients before enrolment. The results of the study will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT06037889).

Infarct growth velocity predicts early neurological outcomes in single subcortical infarction

In single subcortical infarction (SSI), changes in lesion size are a major determinant of early neurological deterioration. We evaluated the association between END and infarct growth velocity (IGV) in patients with SSI. We included consecutive patients with SSI who underwent MRI within 24 h of symptom onset between 2010 and 2020. END was defined as an increase of ≥ 2 in the total National Institutes of Health Stroke Scale (NIHSS) score or ≥ 1 in the motor NIHSS score. IGV was calculated using the following formula: IGV (mL/h) = diffusion-weighted imaging volume (mL)/time to MRI (h). A total of 604 patients with SSI were evaluated. Multivariable logistic regression analysis showed that IGV remained significant after adjusting for confounders (aOR = 1.34, 95% CI 1.12-1.61). In a subgroup analysis based on the type of SSI, only patients with distal SSI showed an association between IGV and END (aOR = 1.64, 95% CI 1.24-2.16). In patients with proximal SSI, IGV did not show any statistical association with END. In conclusion, IGV was positively associated with END in patients with SSI. IGV should be interpreted differently in clinical settings depending on the location of the SSI lesion.

A method to distinguish the different etiological mechanisms of single subcortical infarction

OBJECTIVES

Although lenticulostriate artery (LSA) territorial infarcts usually appear as single subcortical infarctions (SSIs) on imaging, they are caused by various etiological mechanisms. We aimed to investigate the correlation between LSA morphology and the location or size of infarcts. Besides, we explored whether the location or size of infarcts can predict the presence of middle cerebral artery (MCA) plaques and distinguish the different etiological mechanisms of SSI patients.

METHODS

We prospectively included patients with acute SSI in the LSA territory. The MCA plaques, infarct features, including the number of infarct slices, lowest infarct layer index (LILI), volume, maximum area and diameter, and LSA morphological characteristics, including the number of stems and branches, length, distance, and tortuosity were evaluated.

RESULTS

A total of 105 patients were enrolled. Both the average length and average distance of LSAs were negatively correlated with the maximum infarct area (P=0.048, P=0.028, respectively) and maximum infarct diameter (P=0.016, P=0.010, respectively) on axial examination and were positively correlated with LILI (P=0.020, P=0.003, respectively). The number of LSA branches was associated with the number of infarct slices (P=0.040) and LILI (P=0.043). Moreover, we found that when the LILI=1 or 2 and the number of infarct slices ≥3, the SSI patients were more likely to have MCA plaques (P=0.045).

CONCLUSIONS

SSI patients with a LILI=1 or 2 and infarct slices of ≥3 were more likely to have MCA plaques. Our findings might provide a simple and feasible method to distinguish the different underlying mechanisms of SSIs for clinicians.

Different Predictive Factors for Early Neurological Deterioration Based on the Location of Single Subcortical Infarction: Early Prognosis in Single Subcortical Infarction

BACKGROUND AND PURPOSE

Patients with single subcortical infarctions (SSIs) have relatively a favorable prognosis, but they often experience early neurological deterioration (END). In this study, we compared the predictors for END in patients with SSI according to the location of the lesion.

METHODS

We included consecutive patients with SSIs within 72 hours of symptom onset presenting between 2010 and 2016. END was defined as an increase of ≥2 in the total National Institutes of Health Stroke Scale (NIHSS) score or ≥1 in the motor NIHSS score within the first 72 hours of admission. Along with the analysis of all patients with SSI, we also analyzed the predictors for END in proximal/distal SSI patients and anterior/posterior circulation SSI patients.

RESULTS

A total of 438 patients with SSI were evaluated. In multivariable analysis, initial NIHSS score (adjusted odds ratio, 1.36 [95% CI, 1.15-1.60]), pulsatility index (adjusted odds ratio, 1.25 [95% CI, 1.03-1.52]), parent artery disease (adjusted odds ratio, 2.14 [95% CI, 1.06-4.33]), and neutrophil-to-lymphocyte ratio (adjusted odds ratio, 1.24 [95% CI, 1.04-1.49]) were positively associated with END. In patients with proximal SSI, initial NIHSS score, pulsatility index, parent artery disease, and neutrophil-to-lymphocyte ratio showed positive associations with END. Meanwhile, no variable related to END was found in the distal SSI group. When we compared the predictors for END based on the involved vascular territory, higher initial NIHSS score and neutrophil-to-lymphocyte ratio were significantly associated with END in patients with anterior circulation SSIs. On the contrary, higher pulsatility index values and the presence of parent artery disease were independent predictors for END in patients with SSIs in the posterior circulation.

CONCLUSIONS

Initial NIHSS score, pulsatility index, parent artery disease, and neutrophil-to-lymphocyte ratio are associated with END in patients with SSIs. The frequency and predictors for END differ depending on the location of the SSI.

Triglyceride-glucose index is associated with early neurological deterioration in single subcortical infarction: Early prognosis in single subcortical infarctions

BACKGROUND

The research about the influence of triglyceride-glucose index on early prognosis in stroke is lacking.

AIMS

In this study, we evaluated the association between triglyceride-glucose index and early neurological deterioration in patients with single subcortical infarctions.

METHODS

Consecutive patients with single subcortical infarctions within 72 h of symptom onset between 2011 and 2015. Early neurological deterioration was defined as an increase of ≥2 in the total NIHSS score or ≥1 in the motor NIHSS score. The triglyceride-glucose index was calculated using the log scale of fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2.

RESULTS

A total of 305 patients with single subcortical infarctions were evaluated. In multivariable analysis, the triglyceride-glucose index (adjusted odds ratio [aOR] = 2.94, 95% confidence interval [CI] = 1.58-5.45) and age (aOR = 1.05, 95% CI = 1.01-1.09) were associated with early neurological deterioration. In subgroup analysis according to the type of single subcortical infarctions, only patients with proximal single subcortical infarctions showed a significant association between the triglyceride-glucose index and early neurological deterioration (aOR = 2.92, 95% CI = 1.35-6.29). On the other hand, there was no statistical significance in patients with distal single subcortical infarctions. Patients with untreated diabetes also showed the close association between the triglyceride-glucose index and early neurological deterioration (aOR = 3.94, 95% CI = 1.47-10.52).

CONCLUSIONS

The triglyceride-glucose index was associated with early neurological deterioration in single subcortical infarctions. This association differed depending on the location of lesion and the presence of untreated diabetes.

Association between Low-Density Lipoprotein Cholesterol Levels and Proximal Single Subcortical Infarction in Comparison with Distal Single Subcortical Infarction

PURPOSE

Single subcortical infarction (SSI) in the middle cerebral artery (MCA) territory can be classified into proximal SSI (pSSI) and distal SSI (dSSI) based on the heterogeneous pathogenesis. It is hypothesized that pSSI is more relevant with atherosclerosis, as low-density lipoprotein cholesterol (LDL-C) is the major atherogenic lipoprotein, we conducted the present study to investigate the association between LDL-C levels and pSSI in comparison with dSSI.

PATIENTS AND METHODS

This study is a subset of the Chinese Intracranial Atherosclerosis study. A total of 380 with SSI in the MCA territory classified as small artery occlusion stroke were enrolled in this study. 3.0-T magnetic resonance imaging (MRI) was performed to categorize the participants into two groups, pSSI (extending to the basal surface of MCA) and dSSI (not extending to the basal surface of MCA).

RESULTS

Out of the 380 enrolled participants (273 men and 107 women), the proportion of pSSI and dSSI were 53.2% (202/380) versus 46.8% (178/380) based on MRI. The results of univariate and multivariate logistic regression were both at the borderline level of statistical significance. Further stratified analyses revealed that age is an interaction factor (P = 0.03), the association between LDL-C levels and the pSSI in participants aged over 65 had a significant positive relation (OR: 1.56; 95%CI: 1.14-2.12).

CONCLUSION

LDL-C level is an independent risk factor for pSSI in patients aged over 65. Our result is in accordance with the hypothesis that pSSI is more relevant with atherosclerosis, thus appropriate treatment should be applied differently to pSSI and dSSI.

A cohort study of isolated brainstem infarction based on head MR imaging and clinical findings

Objective

The prognosis of patients with isolated brainstem infarction (BSI) differs on an individual patient basis. This study was undertaken to analyze the influences of different imaging and clinical features with the prognosis of patients with BSI.

Methods

The study population was derived from a multicenter study of intracranial atherosclerosis in China. In the present study, 300 patients were selected who had experienced non-cardiogenic brain stem infarction within the prior 7 days. Evaluations included clinical characteristics, location and size of the brainstem infarction, and whether the infarction was located in multiple perforating branches of the brainstem. Poor prognosis was defined as the presence of disability within 1 year from the onset of disease.

Results

In total, 281 patients were followed up at 1 year post-infarction. Of these 281 patients, 84 (29.9%) exhibited disability at 1 year; these patients showed a median National Institutes of Health Stroke Scale score of 6 on admission. Multiple logistic regression analysis showed that patients with BSI located in the territory of multiple perforating arteries, who were discharged without administration of statins, showed a poor 1-year prognosis.

Conclusion

Isolated BSI involving multiple perforating arteries, without statin medication at discharge, indicated poor prognosis for patients with BSI.

An Objective Measurement of Lacunar Infarct Location from the Middle Cerebral Artery Stem

BACKGROUND

There is emerging interest in the relationship between neuroimaging location of lacunar infarcts and underlying stroke risk factors. Recent methods used for localization of lacunar infarcts are affected by high inter-rater variability. We used a novel algorithm-driven method that provided quantitative assessment of the distance of the lacunar infarct from the origins of the lenticulostriate arteries.

METHODS

We conducted a retrospective analysis of patients who presented with lacunar infarcts between 2007 and 2011. Diffusion-weighted imaging and magnetic resonance angiography were used to manually mark the infarct lesion and the ipsilateral origins of lenticulostriate arteries. A 3-dimensional distance formula computed the distance between the infarct and the arterial region of interest. All distances were adjusted for brain volumes. Agreement testing using 2 blinded assessors was used to determine reproducibility of this method.

RESULTS

One hundred and ten patients were included in our study, with a median age of 72 years (interquartile range 58-81); 67 (61%) were male and 33 (30%) had hypertension and other vascular risk factors including hypercholesterolemia 45 (41%), smoking 33 (30%), diabetes 24 (22%), ischemic heart disease 18 (16%), and atrial fibrillation 9 (8%). The agreement test for 33 patients demonstrated an intraclass correlation of .89 and Lin's correlation coefficient of .89 (95% confidence interval .816-.963). The median distance for the study cohort was 24.5 mm, with shorter median distances of 13.7 mm observed in patients with atrial fibrillation (P value < .005).

CONCLUSION

Our study used a novel method to calculate a distance measurement, which has high inter-rater correlation.

Remote Diffusion-Weighted Imaging Lesions in Intracerebral Hemorrhage: Characteristics, Mechanisms, Outcomes, and Therapeutic Implications

Spontaneous intracerebral hemorrhage (ICH) is one of the most fatal form of stroke, with high mortality and disability rate. Small diffusion-weighed imaging lesions are not rare to see in regions remote from the hematoma after ICH and have been generally considered as related with poor outcome. In this review, we described the characteristics of remote ischemic lesions, discussed the possible mechanisms and clinical outcomes of these lesions, and evaluated the potential therapeutic implications.

Diffusion magnetic resonance imaging in cerebral small vessel disease

Cerebral small vessel disease (SVD) is frequent in the elderly, and accounts for a wide spectrum of clinical and radiological manifestations. This report summarizes the most important findings obtained using diffusion MRI (DWI) in SVD. With DWI and apparent diffusion coefficient (ADC) maps, recent ischemic lesions can easily be detected after acute stroke in SVD, while even multiple simultaneous lesions may be observed. Microstructural changes are frequent in SVD, with increases in diffusivity and decreases in anisotropy being the most reliable findings observed, mainly in white matter. These tissue changes are associated with clinical severity and especially executive dysfunction. They can also precede the usual MRI markers of SVD, such as white matter hyperintensities, microbleeds and lacunes. Thus, DWI may reveal surrogate markers of SVD progression and offer a better understanding of their underlying mechanisms.

Pathogenic Heterogeneity of Distal Single Small Subcortical Lenticulostriate Infarctions Based on Lesion Size

BACKGROUND

Single small subcortical infarctions (SSSIs) in the lenticulostriate artery territory can be classified as proximal single small subcortical infarction (pSSSI) or distal single small subcortical infarction (dSSSI) lesions depending on the involvement of the lowest part of the basal ganglia. It was reported that pSSSI lesions have more characteristics of large artery atherosclerosis, whereas dSSSI lesions are more characteristic of small vessel disease. Because infarction of small vessels is more likely to be distal and may result in small lesions, we hypothesized that the clinical features of dSSSI lesions might be heterogeneous and classified based on lesion size.

METHODS

Lenticulostriate SSSI patients admitted within 72 hours of stroke onset were included from a prospectively registered hospital-based stroke database. We determined the location (lowest slice [LS] involved) and size (total number of slices [TNS] involved) of SSSIs on magnetic resonance imagings. Based on lesion location, SSSIs were divided into pSSSI (LS ≤ 2) and dSSSI (LS > 2); the latter were further subdivided into distal and small SSSI (ds-SSSI, TNS ≤ 2) or distal and large SSSI (dl-SSSI, TNS > 2). The clinical characteristics were compared between different groups.

RESULTS

A total of 204 patients were included out of 1158 patients registered in the database. We found that ds-SSSI was most often associated with severe white matter hyperintensities. However, patients with dl-SSSI most often had a higher rate of additional concurrent atherosclerotic disease as coronary heart disease, compared to patients with ds-SSSI.

CONCLUSIONS

The pathogenesis of dSSSI may be heterogeneous depending on lesion size.

Clinical correlates of infarct shape and volume in lacunar strokes: the Secondary Prevention of Small Subcortical Strokes trial

BACKGROUND AND PURPOSE

Infarct size and location are thought to correlate with different mechanisms of lacunar infarcts. We examined the relationship between the size and shape of lacunar infarcts and vascular risk factors and outcomes.

METHODS

We studied 1679 participants in the Secondary Prevention of Small Subcortical Stroke trial with a lacunar infarct visualized on diffusion-weighted imaging. Infarct volume was measured planimetrically, and shape was classified based on visual analysis after 3-dimensional reconstruction of axial MRI slices.

RESULTS

Infarct shape was ovoid/spheroid in 63%, slab in 12%, stick in 7%, and multicomponent in 17%. Median infarct volume was smallest in ovoid/spheroid relative to other shapes: 0.46, 0.65, 0.54, and 0.90 mL, respectively (P<0.001). Distributions of vascular risk factors were similar across the 4 groups except that patients in the ovoid/spheroid and stick groups were more often diabetic and those with multicomponent had significantly higher blood pressure at study entry. Intracranial stenosis did not differ among groups (P=0.2). Infarct volume was not associated with vascular risk factors. Increased volume was associated with worse functional status at baseline and 3 months. Overall, 162 recurrent strokes occurred during an average of 3.4 years of follow-up with no difference in recurrent ischemic stroke rate by shape or volume.

CONCLUSIONS

In patients with recent lacunar stroke, vascular risk factor profile was similar among the different infarct shapes and sizes. Infarct size correlated with worse short-term functional outcome. Neither shape nor volume was predictive of stroke recurrence.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00059306.

The 'silence' of silent brain infarctions may be related to chronic ischemic preconditioning and nonstrategic locations rather than to a small infarction size

OBJECTIVE

Silent brain infarctions are the silent cerebrovascular events that are distinguished from symptomatic lacunar infarctions by their 'silence'; the origin of these infarctions is still unclear. This study analyzed the characteristics of silent and symptomatic lacunar infarctions and sought to explore the mechanism of this 'silence'.

METHODS

In total, 156 patients with only silent brain infarctions, 90 with only symptomatic lacunar infarctions, 160 with both silent and symptomatic lacunar infarctions, and 115 without any infarctions were recruited. Vascular risk factors, leukoaraiosis, and vascular assessment results were compared. The National Institutes of Health Stroke Scale scores were compared between patients with only symptomatic lacunar infarctions and patients with two types of infarctions. The locations of all of the infarctions were evaluated. The evolution of the two types of infarctions was retrospectively studied by comparing the infarcts on the magnetic resonance images of 63 patients obtained at different times.

RESULTS

The main risk factors for silent brain infarctions were hypertension, age, and advanced leukoaraiosis; the main factors for symptomatic lacunar infarctions were hypertension, atrial fibrillation, and atherosclerosis of relevant arteries. The neurological deficits of patients with only symptomatic lacunar infarctions were more severe than those of patients with both types of infarctions. More silent brain infarctions were located in the corona radiata and basal ganglia; these locations were different from those of the symptomatic lacunar infarctions. The initial sizes of the symptomatic lacunar infarctions were larger than the silent brain infarctions, whereas the final sizes were almost equal between the two groups.

CONCLUSIONS

Chronic ischemic preconditioning and nonstrategic locations may be the main reasons for the 'silence' of silent brain infarctions.