Predictors of new remote cerebral microbleeds after IV thrombolysis for ischemic stroke

Prevalence, Risk Factors, and Clinical Outcomes of New Cerebral Microbleeds After Intravenous Thrombolysis in Acute Ischemic Stroke: a Systematic Review and Meta-analysis

BACKGROUND

Cerebral microbleeds (CMBs) are common in the elderly population, and are associated with an increased risk of stroke and dementia. An acute ischemic stroke event can make CMBs develop rapidly. However, the progression of CMBs after intravenous thrombolysis is not well understood.

METHODS

Following a previously registered protocol, PubMed, Web of Science, and Embase databases were systematically searched to identify relevant literature up to August 2022. Cohort studies that reported new CMBs in patients with acute ischemic stroke undergoing intravenous thrombolysis were included. Random effects models were used to calculate the pooled estimates.

RESULTS

Seven studies with 1079 patients were included in the meta-analysis. The pooled new CMBs prevalence was 7.6% (95% CI 3.9-14.3%) and 63.6% new CMBs were located in the cerebral lobes. Compared with patients without new CMBs, those with new CMBs were older, had a higher proportion of hypertension, and had higher systolic blood pressure and baseline CMBs burden. The presence of new CMBs increased the likelihood of remote intracerebral hemorrhage (OR 28.75, 95% CI 8.58-96.38) and symptomatic intracerebral hemorrhage (OR 15.49, 95% CI 3.21-74.73) but was not related to functional outcomes or hemorrhagic transformation.

CONCLUSIONS

The prevalence of new CMBs after intravenous thrombolysis was approximately 7.6%. The presence of new CMBs is associated with remote and symptomatic intracerebral hemorrhage following intravenous thrombolysis. Considering the potential long-term adverse effects of CMBs progression, patients at a high risk of developing new CMBs should be identified based on potential risk factors.

New Cerebral Microbleeds After Catheter-Based Structural Heart Interventions: An Exploratory Analysis

Background Cerebral microbleeds (CMBs) are increasingly recognized as "covert" brain lesions indicating increased risk of future neurological events. However, data on CMBs in patients undergoing catheter-based structural heart interventions are scarce. Therefore, we assessed occurrence and predictors of new CMBs in patients undergoing catheter-based left atrial appendage closure and percutaneous mitral valve repair using the MitraClip System. Methods and Results We conducted an exploratory analysis using data derived from 2 prospective, observational studies. Eligible patients underwent cerebral magnetic resonance imaging (3 Tesla) examinations and cognitive tests (using the Montreal Cognitive Assessment) before and after catheter-based left atrial appendage closure and percutaneous mitral valve repair. Forty-seven patients (53% men; median age, 77 years) were included. New CMBs occurred in 17 of 47 patients (36%) following catheter-based structural heart interventions. Occurrences of new CMBs did not differ significantly between patients undergoing catheter-based left atrial appendage closure and percutaneous mitral valve repair (7/25 versus 10/22; P=0.348). In univariable analysis, longer procedure time was significantly associated with new CMBs. Adjustment for heparin attenuated this association (adjusted odds ratio [per 30 minutes]: 1.77 [95% CI, 0.92-3.83]; P=0.090). Conclusions New CMBs occur in approximately one-third of patients after catheter-based left atrial appendage closure and percutaneous mitral valve repair using the MitraClip System. Our data suggest that longer duration of the procedure may be a risk factor for new CMBs. Future studies in larger populations are needed to further investigate their clinical relevance. Clinical Trial Registration German Clinical Trials Register: DRKS00010300 (https://drks.de/search/en/trial/DRKS00010300); ClinicalTrials.gov : NCT03104556 (https://clinicaltrials.gov/ct2/show/NCT03104556?term=NCT03104556&draw=2&rank=1).

Brain hemorrhage on 24h-CT and functional outcome in stroke patients with cerebral amyloid angiopathy features on pre-thrombolysis MRI treated with intravenous thrombolysis: A case series

BACKGROUND AND OBJECTIVES

In stroke patients treated with intravenous thrombolysis (IVT), presence and high number of strictly lobar cerebral microbleeds (compatible with cerebral amyloid angiopathy, CAA) seems to be associated with increased risk of hemorrhagic transformation, symptomatic hemorrhagic transformation, remote hemorrhage, and poor functional outcome. Some of these CAA patients with cerebral microbleeds also have chronic lobar intracerebral hemorrhage. Few data are available on IVT-treated CAA patients showing cortical superficial siderosis. There are no reports studying factors associated with brain hemorrhagic complication or functional outcome in IVT-treated CAA patients. We present a case series study of IVT-treated stroke patients with CAA features on pre-IVT MRI in whom we have evaluated brain hemorrhagic complications on 24 h-CT and functional outcome after IVT.

MATERIAL AND METHODS

In our stroke center, IVT decision in patients with CAA MRI features is at the physician's discretion. We retrospectively screened our stroke database between January 2015 and July 2022 for pre-IVT imaging of 959 consecutive IVT-treated stroke patients without ongoing anticoagulation therapy for probable CAA MRI features defined by modified Boston criteria. After exclusion of 119 patients with missing MRI (n = 47), MRI showing motion artefacts (n = 49) or with alternative chronic brain hemorrhage cause on MRI (n = 23), 15 IVT-treated patients with probable CAA on pre-IVT MRI were identified. In these 15 patients, clinical, biological and MRI characteristics were compared between patients with vs. without post-IVT hemorrhage and between patients with poor (MRS 3-6) vs. good (MRS 0-2) functional outcome at discharge.

RESULTS

Two patients showed brain hemorrhage on 24 h-CT and both died after 40 and 31 days respectively. The remaining patients had no brain hemorrhage and showed very good outcome except one. Atrial fibrillation (p = 0.029) and Fazekas scale (p = 0.029) were associated with brain hemorrhage whereas atrial fibrillation (p = 0.0022), NIHSS (p = 0.027), blood glucose level (p = 0.024), CRP (p = 0.022) and DWI ASPECT (p = 0.016) were associated with poor outcome.

DISCUSSION

Consequences of IVT in CAA patients can be dramatic. Larger studies are needed to compare IVT risks and outcome between CAA and non-CAA patients, also including CAA patients with chronic intracerebral hemorrhage or cortical superficial siderosis. In addition, future studies should try to identify clinical, biological and radiological features at high risk for brain hemorrhage and poor outcome in order to assess the risk-benefit ratio for IVT in CAA.

CLINICAL TRIAL REGISTRATION-URL

http://www.

CLINICALTRIALS

gov. Unique identifier: NCT05565144.

Total Cerebral Small Vessel Disease Score and Cerebral Bleeding Risk in Patients With Acute Stroke Treated With Intravenous Thrombolysis

Objective

The aim of this study was to investigate the association of total cerebral small vessel disease (cSVD) score with the risk of intracerebral hemorrhage (ICH) in patients with acute ischemic stroke who received intravenous thrombolysis (IVT) using recombinant tissue-plasminogen activator (rt-PA).

Methods

We retrospectively reviewed clinical data from two stroke registries of patients with acute ischemic stroke treated with IVT. We assessed the baseline magnetic resonance (MR) visible cSVD markers and total cSVD score (ranging from 0 to 4) between patients with and without ICH after IVT. Logistic regression analysis was used to determine the association of total cSVD score with the risk of ICH after IVT, adjusted for cofounders selected by least absolute shrinkage and selection operator (LASSO). We additionally performed an E-value analysis to fully explain away a specific exposure-outcome association. Receiver operating characteristic (ROC) curve analysis was used to quantify the predictive potential of the total cSVD score for any ICH after IVT.

Results

Among 271 eligible patients, 55 (20.3%) patients experienced any ICH, 16 (5.9%) patients experienced a symptomatic ICH (sICH), and 5 (1.85%) patients had remote intracranial parenchymal hemorrhage (rPH). Logistic regression analysis showed that the risk of any ICH increased with increasing cSVD score [per unit increase, adjusted odds ratio (OR) 2.03, 95% CI 1.22–3.41, P = 0.007]. Sensitivity analyses using E-value revealed that it would need moderately robust unobserved confounding to render the exposure-outcome (cSVD-any ICH) association null. ROC analysis showed that compared with the National Institutes of Health Stroke Scale (NIHSS) score alone, a combination of cSVD and NIHSS score had a larger area under the curve for any ICH (0.811, 95% CI 0.756–0.866 vs. 0.784, 95% CI 0.723–0.846, P = 0.0004).

Conclusion

The total cSVD score is associated with an increased risk of any ICH after IVT and improves prediction for any ICH compared with NIHSS alone.

Clinical Prediction Model for Screening Acute Ischemic Stroke Patients With More Than 10 Cerebral Microbleeds

Background

Hemorrhagic transformation is one of the most serious complications in intravenous thrombolysis. Studies show that the existence of more than 10 cerebral microbleeds is strongly associated with hemorrhagic transformation. The current study attempts to develop and validate a clinical prediction model of more than 10 cerebral microbleeds.

Methods

We reviewed the computed tomography markers of cerebral small vessel diseases and the basic clinical information of acute ischemic stroke patients who were investigated using susceptibility weighted imaging from 2018 to 2021. A clinical prediction model of more than 10 cerebral microbleeds was established. Discrimination, calibration, and the net benefit of the model were assessed. Finally, a validation was conducted to evaluate the accuracy and stability of the model.

Results

The multivariate logistic regression model showed hypertension, and some computed tomography markers (leukoaraiosis, lacunar infarctions, brain atrophy) were independent risk factors of more than 10 cerebral microbleeds. These risk factors were used for establishing the clinical prediction model. The area under the receiver operating characteristic curve (AUC) was 0.894 (95% CI: 0.870–0.919); Hosmer–Lemeshow chi-squared test yielded χ² = 3.946 (P = 0.862). The clinical decision cure of the model was higher than the two extreme lines. The simplified score of the model ranged from 0 to 12. The model in the internal and external validation cohort also had good discrimination (AUC 0.902, 95% CI: 0.868–0.937; AUC 0.914, 95% CI: 0.882–0.945) and calibration (P = 0.157, 0.247), and patients gained a net benefit from the model.

Conclusions

We developed and validated a simple scoring tool for acute ischemic stroke patients with more than 10 cerebral microbleeds; this tool may be beneficial for paradigm decision regarding intravenous recombinant tissue plasminogen activator therapy of acute ischemic stroke.

New Remote Cerebral Microbleeds on T2*-Weighted Echo Planar MRI After Intravenous Thrombolysis for Acute Ischemic Stroke

Background

The main and well-defined complication of intravenous administration of recombinant tissue plasminogen activator (tPA) in patients with acute ischemic stroke (AIS) is symptomatic intracranial hemorrhage (sICH). However, rtPA might also be connected with the formation of cerebral microbleeds (CMBs), located remotely from the ischemic lesions, that may remain clinically silent. This association might be important because the load of CMBs has been associated with cognitive impairment. We investigated whether administration of rtPA in AIS results in the appearance of new CMBs and if the initial load of CMBs is associated with hemorrhagic transformation.

Methods

A total of fifty-nine consecutive patients with AIS treated with rtPA underwent MRI including T2^*-weighted Echo Planar Imaging (T2^*-EPI) shortly before and 7–9 days after rtPA administration. We calculated the load of new CMBs located outside the MR diffusion restriction area in the follow-up imaging and assessed hemorrhagic transformation with ECASS-II scoring.

Results

A total of forty-nine patients were included for the final analysis. On initial T2^*-EPI-GRE, 37 baseline microbleeds (CMBs) were observed in 14 patients (28.6%). On follow-up T2^*-EPI-GRE amount of CMBs increased to a total number of 103. New CMBs were found in 5 (14.3%) of 35 patients without and in 9 (64.3%) of 14 with any baseline CMBs. Multiple logistic regression analysis indicated that presence of baseline CMBs (risk ratio [RR] 5.95, 95% CI 2.69–13.20, p < 0.001) and lower platelets level (risk ratio [RR] 0.992, 95% CI 0.986–0.998, p = 0.007) were independently associated with new CMBs. The baseline load of CMBs was not associated with the risk of hemorrhagic transformation.

Conclusion

In this study, new CMBs were found in nearly 30% of patients with AIS on the 7–9 days after rtPA treatment. Baseline CMBs correlated with a higher risk of new CMBs appearing after the rtPA treatment, independently of other factors. At the same time, in our sample, baseline CMBs did not correlate with an increased risk of hemorrhagic transformation. Since the associations between the CMBs load and cognitive impairment have already been proved, further studies are warranted to investigate possible associations between the thrombolytic treatment of patients with AIS, mainly those with baseline CMBs, and the risk of earlier cognitive decline.

[Intracerebral hemorrhage under platelet inhibition and oral anticoagulation in patients with cerebral amyloid angiopathy]

Die Durchführung einer oralen Antikoagulation ist bei Patienten mit einer zerebralen Amyloidangiopathie eine therapeutische Herausforderung. Die Assoziation der zerebralen Amyloidangiopathie mit Lobärblutungen, eine hohe Mortalität intrazerebraler Blutungen insbesondere unter oraler Antikoagulation sowie das hohe Rezidivrisiko solcher Blutungen erfordern eine strenge und interdisziplinäre Risiko-Nutzen-Abwägung. Vitamin-K-Antagonisten erhöhen das Risiko für die mit intrazerebralen Blutungen vergesellschaftete Mortalität um 60 % und sollten daher möglichst vermieden bzw. speziellen klinischen Situationen (z. B. mechanischer Aortenklappenersatz) vorbehalten sein. Auch der Einsatz von neuen oralen Antikoagulanzien und Thrombozytenaggregationshemmern bedarf einer strengen Risiko-Nutzen-Abwägung, da auch diese Substanzen das zerebrale Blutungsrisiko erhöhen. Insbesondere bei Patienten mit einer absoluten Arrhyhtmie bei Vorhofflimmern ist der interventionelle Vorhofohrverschluss eine therapeutische Alternative. Darüber hinaus sind weitere klinische Implikationen bei Patienten mit zerebraler Amyloidangiopathie Gegenstand dieser Literaturübersicht, beispielsweise Besonderheiten nach akutem ischämischem Schlaganfall und erforderlicher Sekundärprophylaxe, bei vorherigen intrazerebralen Blutungen und bei Patienten mit kognitiven Defiziten.

Cerebral microbleeds development after stroke thrombolysis: A secondary analysis of the THAWS randomized clinical trial

BACKGROUND AND AIM

We determined to investigate the incidence and clinical impact of new cerebral microbleeds after intravenous thrombolysis in patients with acute stroke.

METHODS

The THAWS was a multicenter, randomized trial to study the efficacy and safety of intravenous thrombolysis with alteplase in patients with wake-up stroke or unknown onset stroke. Prescheduled T2*-weighted imaging assessed cerebral microbleeds at three time points: baseline, 22-36 h, and 7-14 days. Outcomes included new cerebral microbleeds development, modified Rankin Scale (mRS) ≥3 at 90 days, and change in the National Institutes of Health Stroke Scale (NIHSS) score from 24 h to 7 days.

RESULTS

Of all 131 patients randomized in the THAWS trial, 113 patients (mean 74.3 ± 12.6 years, 50 female, 62 allocated to intravenous thrombolysis) were available for analysis. Overall, 46 (41%) had baseline cerebral microbleeds (15 strictly lobar cerebral microbleeds, 14 mixed cerebral microbleeds, and 17 deep cerebral microbleeds). New cerebral microbleeds only emerged in the intravenous thrombolysis group (seven patients, 11%) within a median of 28.3 h, and did not additionally increase within a median of 7.35 days. In adjusted models, number of cerebral microbleeds (relative risk (RR) 1.30, 95% confidence interval (CI): 1.17-1.44), mixed distribution (RR 19.2, 95% CI: 3.94-93.7), and cerebral microbleeds burden ≥5 (RR 44.9, 95% CI: 5.78-349.8) were associated with new cerebral microbleeds. New cerebral microbleeds were associated with an increase in NIHSS score (p = 0.023). Treatment with alteplase in patients with baseline ≥5 cerebral microbleeds resulted in a numerical shift toward worse outcomes on ordinal mRS (median [IQR]; 4 [3-4] vs. 0 [0-3]), compared with those with <5 cerebral microbleeds (common odds ratio 17.1, 95% CI: 0.76-382.8). The association of baseline ≥5 cerebral microbleeds with ordinal mRS score differed according to the treatment group (p interaction = 0.042).

CONCLUSION

New cerebral microbleeds developed within 36 h in 11% of the patients after intravenous thrombolysis, and they were significantly associated with mixed-distribution and ≥5 cerebral microbleeds. New cerebral microbleeds development might impede neurological improvement. Furthermore, cerebral microbleeds burden might affect the effect of alteplase.

RP11-362K2.2:RP11-767I20.1 Genetic Variation Is Associated with Post-Reperfusion Therapy Parenchymal Hematoma. A GWAS Meta-Analysis

Stroke is one of the most common causes of death and disability. Reperfusion therapies are the only treatment available during the acute phase of stroke. Due to recent clinical trials, these therapies may increase their frequency of use by extending the time-window administration, which may lead to an increase in complications such as hemorrhagic transformation, with parenchymal hematoma (PH) being the more severe subtype, associated with higher mortality and disability rates. Our aim was to find genetic risk factors associated with PH, as that could provide molecular targets/pathways for their prevention/treatment and study its genetic correlations to find traits sharing genetic background. We performed a GWAS and meta-analysis, following standard quality controls and association analysis (fastGWAS), adjusting age, NIHSS, and principal components. FUMA was used to annotate, prioritize, visualize, and interpret the meta-analysis results. The total number of patients in the meta-analysis was 2034 (216 cases and 1818 controls). We found rs79770152 having a genome-wide significant association (beta 0.09, p-value 3.90 × 10⁻⁸) located in the RP11-362K2.2:RP11-767I20.1 gene and a suggestive variant (rs13297983: beta 0.07, p-value 6.10 × 10⁻⁸) located in PCSK5 associated with PH occurrence. The genetic correlation showed a shared genetic background of PH with Alzheimer’s disease and white matter hyperintensities. In addition, genes containing the ten most significant associations have been related to aggregated amyloid-β, tau protein, white matter microstructure, inflammation, and matrix metalloproteinases.

Effect of butylphthalide on new cerebral microbleeds in patients with acute ischemic stroke

BACKGROUND

To evaluate the effect of dl-3-N-butylphthalide (NBP) on new cerebral microbleeds (CMBs) in patients with acute ischemic stroke (AIS).

METHODS

We will prospectively enroll patients with AIS admitted to the stroke center of Jingjiang People's Hospital. Qualified participants will be randomly assigned to either the NBP group (NBP injection) or the control group (NBP injection placebo) in a ratio of 1:1. Patients will complete the brain magnetic resonance imaging within 48 hours and 14 days after stroke onset to observe the CMBs through susceptibility weighted imaging, and evaluate whether the use of NBP will affect the new CMBs in AIS patients. SPSS 20.0 will be used for statistical analyses.

RESULT

We will provide practical and targeted results assessing the safety of NBP for AIS patients, to provide reference for clinical use of NBP.

CONCLUSION

The stronger evidence about the effect of NBP on new CMBs in AIS patients will be provided for clinicians.

Single and simultaneous multiple intracerebral hemorrhages: a radiological review

Simultaneous multiple intracerebral hemorrhage (SMICH) is defined as ICH in two or more discrete noncontiguous acute intraparenchymal locations on initial CT. About 5% of ICH patients present with SMICH. ICH/SMICH etiology is classically divided into disorders of primary or secondary origin. About half of primary SMICH cases are caused by cerebral amyloid angiopathy or hypertensive arteriopathy. In this review, we will discuss the radiological features associated with the different causes of primary and secondary ICH and SMICH. Due to its rarity and the associated high morbidity and mortality, we will focus in particular on SMICH.