Future of Endovascular and Surgical Treatments of Atherosclerotic Intracranial Stenosis.

Intracranial atherosclerotic disease and resultant intracranial stenosis is a global leading cause of stroke, and poses an ongoing treatment challenge. Among patients with intracranial stenosis, those with hemodynamic compromise are at high risk for recurrent stroke despite medical therapy and risk factor modification. Revascularization of the hypoperfused territory is the most plausible treatment strategy for these high-risk patients, yet surgical and endovascular therapies have not yet shown to be sufficiently safe and effective in randomized controlled trials. Advances in diagnostic and therapeutic technologies have led to a resurgence of interest in surgical and endovascular treatment strategies, with a growing body of evidence to support their further evaluation in the treatment of select patient populations. This review outlines the current and emerging endovascular and surgical treatments and highlights promising future management strategies.

Endovascular therapy versus best medical management in distal medium middle cerebral artery acute ischaemic stroke: a multinational multicentre propensity score-matched study.

BACKGROUND: The efficacy of endovascular treatment (EVT) in acute ischaemic stroke due to distal medium vessel occlusion (DMVO) remains uncertain. Our study aimed to evaluate the safety and efficacy of EVT compared with the best medical management (BMM) in DMVO. METHODS: In this prospectively collected, retrospectively reviewed, multicentre cohort study, we analysed data from the Multicentre Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy registry. Patients with acute ischaemic stroke due to DMVO in the M2, M3 and M4 segments who underwent EVT or received BMM were included. Primary outcome measures comprised 10 co-primary endpoints, including functional independence (mRS 0-2), excellent outcome (mRS 0-1), mortality (mRS 6) and haemorrhagic complications. Propensity score matching was employed to balance the cohorts. RESULTS: Among 2125 patients included in the primary analysis, 1713 received EVT and 412 received BMM. After propensity score matching, each group comprised 391 patients. At 90 days, no significant difference was observed in achieving mRS 0-2 between EVT and BMM (adjusted OR 1.00, 95% CI 0.67 to 1.50, p>0.99). However, EVT was associated with higher rates of symptomatic intracerebral haemorrhage (8.4% vs 3.0%, adjusted OR 3.56, 95% CI 1.69 to 7.48, p<0.001) and any intracranial haemorrhage (37% vs 19%, adjusted OR 2.61, 95% CI 1.81 to 3.78, p<0.001). Mortality rates were similar between groups (13% in both, adjusted OR 1.48, 95% CI 0.87 to 2.51, p=0.15). CONCLUSION: Our findings suggest that while EVT does not significantly improve functional outcomes compared with BMM in DMVO, it is associated with higher risks of haemorrhagic complications. These results support a cautious approach to the use of EVT in DMVO and highlight the need for further prospective randomised trials to refine treatment strategies.

A contemporary analysis of surgical ligation versus endovascular embolization in patients with intracranial dural arteriovenous fistulas: a propensity score-matched and mixed-effects model study.

OBJECTIVE: Intracranial dural arteriovenous fistulas (dAVFs) are rare vascular lesions that can be asymptomatic or can lead to devastating hemorrhage based on the dAVF's aggressiveness. Several approaches can be taken to treat dAVFs, such as endovascular embolization and surgical ligation. However, very few studies have evaluated the influence of surgery compared to endovascular approaches on patient outcomes. This study was performed to analyze the clinical characteristics and outcomes of patients who underwent treatment for intracranial dAVF in which either endovascular embolization or microsurgical ligation was used. METHODS: The Nationwide Readmissions Database was reviewed for all patients who underwent treatment for dAVFs (n = 18,152) between 2016 and 2019. Patients who received only surgical ligation or endovascular embolization (i.e., not both) were included. Variables regarding demographics, clinical outcomes, and healthcare utilization were queried. Primary outcome measures were nonroutine discharge, 1-year readmission, top quartile length of stay (LOS), and top quartile of inpatient all-payer cost. Propensity score matching was performed to evaluate the influence of either surgery or embolization on patient outcomes. Receiver operating characteristic (ROC) curves were created for each outcome measure. The area under the curve (AUC) of each ROC was used to estimate mixed-effects model performance. RESULTS: Following propensity score matching, 127 and 113 patients made up the surgical ligation and endovascular embolization cohort, respectively. There were no differences found in age (p = 0.16), sex (p = 0.57), or average Elixhauser Comorbidity Index (p = 0.32). Patients receiving surgical ligation had lower odds of readmission (OR 0.37, p = 0.028) and greater odds of nonroutine discharge (OR 2.21, p = 0.03) compared to patients who underwent endovascular embolization. The authors found no differences in the top quartile of LOS (p = 0.84), top quartile of cost (p = 0.38), or mortality (p > 0.99) between cohorts. ROC curves revealed that the mixed-effects models inclusive of approach outperformed models agnostic to approach with respect to nonroutine discharge (AUC with approach, 0.871; AUC without approach, 0.850; p = 0.018) and readmission (AUC with approach, 0.686; AUC without approach, 0.651; p = 0.019), but no differences were observed regarding top quartile of LOS (p = 0.17) and top quartile of cost (p = 0.40). CONCLUSIONS: Surgical approach may influence perioperative outcomes in patients treated for intracranial dAVF-most significantly discharge disposition and 1-year readmission. Future longitudinal prospective studies with more clinical detail will be required to fully capture the predictive utility of surgical approach in patients treated for intracranial dAVF, particularly for various dAVF subtypes.

Adult Moyamoya Disease and Syndrome: Current Perspectives and Future Directions: A Scientific Statement From the American Heart Association/American Stroke Association.

Adult moyamoya disease and syndrome are rare disorders with significant morbidity and mortality. A writing group of experts was selected to conduct a literature search, summarize the current knowledge on the topic, and provide a road map for future investigation. The document presents an update in the definitions of moyamoya disease and syndrome, modern methods for diagnosis, and updated information on pathophysiology, epidemiology, and both medical and surgical treatment. Despite recent advancements, there are still many unresolved questions about moyamoya disease and syndrome, including lack of unified diagnostic criteria, reliable biomarkers, better understanding of the underlying pathophysiology, and stronger evidence for treatment guidelines. To advance progress in this area, it is crucial to acknowledge the limitations and weaknesses of current studies and explore new approaches, which are outlined in this scientific statement for future research strategies.

Comparative Analysis of Clinical Practice Guidelines for the Pharmacological Treatment of Type 2 Diabetes Mellitus in Latin America.

PURPOSE OF REVIEW: Type 2 diabetes mellitus (T2DM) is one of the leading causes of death and disability in the world. The majority of diabetes deaths (> 80%) occur in low- and middle-income countries, which are predominant in Latin America. Therefore, the purpose of this article is to compare the clinical practice guideline (CPG) for the pharmacological management of T2DM in Latin America (LA) with international reference guidelines. RECENT FINDINGS: Several LA countries have recently developed CPGs. However, the quality of these guidelines is unknown according to the AGREE II tool and taking as reference three CPGs of international impact: American Diabetes Association (ADA), European Diabetes Association (EASD), and Latin American Diabetes Association (ALAD). Ten CPGs were selected for analysis. The ADA scored > 80% on the AGREE II domains and was selected as the main comparator. Eighty percent of LA CPGs were developed before 2018. Only one was not recommended (all domains < 60%). The CPGs in LA have good quality but are outdated. They have significant gaps compared to the reference. There is a need for improvement, as proposing updates every three years to maintain the best available clinical evidence in all guidelines.

[The impact of novel drugs on the survival of patients with multiple myeloma in two chilean centers]. / Mieloma múltiple en Chile. Uso de drogas noveles en dos centros nacionales.

BACKGROUND: The incorporation of novel drugs, such as proteasome inhibitors and immunomodulators, improved considerably the survival of patients with multiple myeloma. AIM: To evaluate the effect on survival of proteasome inhibitors and immunomodulators in patients with multiple myeloma in two national hospitals. MATERIAL AND METHODS: Review of clinical records from two hospitals of Santiago. Epidemiological, clinical, laboratory and therapeutic data was obtained from 144 patients with multiple myeloma diagnosed between 2002 and 2016. RESULTS: Information was retrieved from 78 patients at one center and from 66 at the other center. The mean age at diagnosis was 58 and 62 years, the proportion of males was 53% and 52%, and presentation at stage III was 34% and 46%, respectively. The use of novel drugs, mainly bortezomib, was 90% in one of the centers and 3% in the other one. The use of autologous stem-cell transplantation was 47% and 3% respectively. The median overall survival of patients from the centers with and without access to novel drugs was 117 and 71 months respectively (p < 0.05). The five-year overall survival was 93 and 43% respectively (p < 0.05). CONCLUSIONS: The use of novel drugs, especially bortezomib, and autologous stem-cell transplantation significantly improved the survival of multiple myeloma patients treated in national hospitals. It is necessary to include them as a first line treatment.

Transvenous Pressure Monitoring Guides Endovascular Treatment of Vein of Galen Malformation: A Technical Note.

INTRODUCTION: Vein of Galen malformations (VGMs) are complex congenital arteriovenous malformations that generally require serial endovascular treatment sessions to slowly correct the high-flow fistulous connections that cause increased venous pressures and ultimately lead to the classic presentations of heart failure, hydrocephalus, and intracranial hemorrhages. Despite the advances in endovascular technology and embolic materials, the resolution of embolization is often limited to the subjective view of diminished flow on angiograms. CASE REPORT: An 8-month-old patient with a VGM developed clinical signs of heart failure and growing head circumference with ventriculomegaly. The patient was treated endovascularly with a transvenous approach for coil embolization while undergoing continuous monitoring of the post-malformation venous pressures. The arterial and venous systolic blood pressures (SBP) were collected at serial time points and used to measure estimated 95% confidence interval bounds for arteriovenous SBP gradients and determine when sufficient coil embolization and flow reduction was thought to be achieved. CONCLUSION: The transvenous pressure monitoring demonstrated progressively increasing pressure gradients between the arterial and venous systems that correlated with the degree of flow reduction on angiographic runs. The patient underwent successful coil embolization of the VGM and had improvement of heart failure and ventricular size in follow-up at 8-month post-op. This provides a novel technique to introduce an objective measurement that can guide the embolization of a VGM.

Elevation of ST-segment in aVR is predictive of cardiogenic shock but not of multivessel disease in inferior myocardial infarction.

INTRODUCTION: Some studies suggest that ST elevation in aVR (aVR-STE) can predict the presence of left main or multivessel disease (MVD) and relates to prognosis. Our purpose was to analyze the relationship of aVR-STE to MVD disease or cardiogenic shock (CS) in patients with inferior myocardial infarction (inferior STEMI). METHODS: We analyzed two cohorts of consecutive patients admitted for inferior STEMI in the Coronary Unit of two university hospitals. ST elevation and ST depression in each derivation were compared between patients with and without MVD and with and without CS. RESULTS: We included 342 patients-19.6% women and 80.4% men-with a median age of 60 (52, 70); 18 patients (5.2%) had MVD, and 25 (7.3%) patients presented CS. There was no relationship between ST elevation or ST depression in either derivation and MVD. In contrast, CS was associated with aVR-STE, ST-segment depression in lead aVL, and the sum of ST-segment depression. aVR-STE of 0.25 mm had a sensitivity of 24.0% and a specificity of 95.9% for CS. After multivariate analysis including clinical variables, aVR-STE was independently associated with CS. CONCLUSIONS: In patients with inferior STEMI, ST-segment analysis was not useful in predicting multivessel disease. aVR-STE was an independent predictor of CS, with high specificity but low sensitivity.

Differential Expression of Vascular Endothelial Growth Factor-A165 Isoforms Between Intracranial Atherosclerosis and Moyamoya Disease.

BACKGROUND: Vascular endothelial growth factor-A165 (VEGF-A165) has been identified as a combination of 2 alternative splice variants: proangiogenic VEGF-A165a and antiangiogenic VEGF-A165b. Intracranial atherosclerotic disease (ICAD) and moyamoya disease (MMD) are 2 main types of intracranial arterial steno-occlusive disorders with distinct capacities for collateral formation. Recent studies indicate that VEGF-A165 regulates collateral growth in ischemia. Therefore, we investigated if there is a distinctive composition of VEGF-A165 isoforms in ICAD and MMD. METHODS: Sixty-six ICAD patients, 6 MMD patients, and 5 controls were enrolled in this prospective study. ICAD and MMD patients received intensive medical management upon enrollment. Surgery was offered to 9 ICAD patients who had recurrent ischemic events, 6 MMD patients, and 5 surgical controls without ICAD. VEGF-A165a and VEGF-A165b plasma levels were measured at baseline, within 1 week after patients having surgery, and at 1, 3, and 6 months after treatment. RESULTS: A significantly higher baseline VEGF-A165a/b ratio was observed in MMD compared to ICAD (P = .016). The VEGF-A165a/b ratio increased significantly and rapidly after surgical treatment in ICAD (P = .026) more so than in MMD and surgical controls. In patients with ICAD receiving intensive medical management, there was also an elevation of the VEGF-A165a/b ratio, but at a slower rate, reaching the peak at 3 months after initiation of treatment (baseline versus 3 months VEGF-A165a/b ratio, P = .028). CONCLUSIONS: Our study shows an increased VEGF-A165a/b ratio in MMD compared to ICAD, and suggests that both intensive medical management and surgical revascularization elevate the VEGF-A165a/b ratio in ICAD patients.

Visual Aids for Patient, Family, and Physician Decision Making About Endovascular Thrombectomy for Acute Ischemic Stroke.

BACKGROUND AND PURPOSE: Rapid decision making optimizes outcomes from endovascular thrombectomy for acute cerebral ischemia. Visual displays facilitate swift review of potential outcomes and can accelerate decision processes. METHODS: From patient-level, pooled randomized trial data, 100 person-icon arrays (Kuiper-Marshall personographs) were generated showing beneficial and adverse effects of endovascular thrombectomy for patients with acute cerebral ischemia and large vessel occlusion using (1) automated (algorithmic) and (2) expert-guided joint outcome table specification. RESULTS: For the full 7-category modified Rankin Scale, thrombectomy added to IV tPA (intravenous tissue-type plasminogen activator) alone had number needed to treat to benefit 2.9 (95% confidence interval, 2.6-3.3) and number needed to harm 68.9 (95% confidence interval, 40-250); thrombectomy for patients ineligible for IV tPA had number needed to treat to benefit 2.3 (95% confidence interval, 2.1-2.5) and number needed to harm 100 (95% confidence interval, 62.5-250). Visual displays of treatment effects on 100 patients showed: with thrombectomy added to IV tPA alone, 34 patients have better disability outcome, including 14 more normal or near normal (modified Rankin Scale, 0-1); with thrombectomy for patients ineligible for IV tPA, 44 patients have a better disability outcome, including 16 more normal or nearly normal. Displays also showed that harm (increased modified Rankin Scale final disability) occurred in 1 of 100 patients in both populations, mediated by increased new territory infarcts. The person-icon figures integrated these outcomes, and early side-effects, in a single display. CONCLUSIONS: Visual decision aids are now available to rapidly educate healthcare providers, patients, and families about benefits and risks of endovascular thrombectomy, both when added to IV tPA in tPA-eligible patients and as the sole reperfusion treatment in tPA-ineligible patients.

Antiangiogenesis and medical therapy failure in intracranial atherosclerosis.

Intracranial atherosclerotic disease (ICAD) is one of the most common causes of stroke worldwide and the one with the worst prognosis. In this study, we assessed the hypothesis that the balance of circulating pro- and antiangiogenic factors plays a role in the evolution of the disease and can be used as a potential marker for the disease course and a target for treatment. Seventy-four patients with severe ICAD were enrolled in this prospective observational study, medically optimized, and followed for 6 months. Thirteen pro- and eight antiangiogenic factors were measured in the participants' serum using a sandwich multiplex ELISA. Angiogenic profiles were calculated using principal component analysis. We tested the association between angiogenic profiles and recurring cerebrovascular events despite intensive medical therapy, disability at 6 months after enrollment, and angiographic neovascularization in patients who failed medical treatment and underwent indirect revascularization surgery. There is a strong association between a functionally antiangiogenic profile and recurrent stroke or TIA in patients with ICAD (OR = 7.2, CI 2.4-34.4). Multivariable regression analysis showed that this antiangiogenic profile was also associated with poor functional status after 6 months (p = 0.002), independent from other clinical features such as history of previous stroke, diabetes, and age. In patients who failed medical management and underwent indirect revascularization surgery, high endostatin and angiostatin levels were also associated with low angiographic neovascularization (p = 0.02). The results of this study point to the striking importance of antiangiogenesis as a determinant of ICAD patient prognosis and suggest a possible new target for therapy.

3D whole-brain vessel wall cardiovascular magnetic resonance imaging: a study on the reliability in the quantification of intracranial vessel dimensions.

BACKGROUND: One of the potentially important applications of three-dimensional (3D) intracranial vessel wall (IVW) cardiovascular magnetic resonance (CMR) is to monitor disease progression and regression via quantitative measurement of IVW morphology during medical management or drug development. However, a prerequisite for this application is to validate that IVW morphologic measurements based on the modality are reliable. In this study we performed comprehensive reliability analysis for the recently proposed whole-brain IVW CMR technique. METHODS: Thirty-four healthy subjects and 10 patients with known intracranial atherosclerotic disease underwent repeat whole-brain IVW CMR scans. In 19 of the 34 subjects, two-dimensional (2D) turbo spin-echo (TSE) scan was performed to serve as a reference for the assessment of vessel dimensions. Lumen and wall volume, normalized wall index, mean and maximum wall thickness were measured in both 3D and 2D IVW CMR images. Scan-rescan, intra-observer, and inter-observer reproducibility of 3D IVW CMR in the quantification of IVW or plaque dimensions were respectively assessed in volunteers and patients as well as for different healthy subjectsub-groups (i.e. < 50 and ≥ 50 years). The agreement in vessel wall and lumen measurements between the 3D technique and the 2D TSE method was also investigated. In addition, the sample size required for future longitudinal clinical studies was calculated. RESULTS: The intra-class correlation coefficient (ICC) and Bland-Altman plots indicated excellent reproducibility and inter-method agreement for all morphologic measurements (All ICCs > 0.75). In addition, all ICCs of patients were equal to or higher than that of healthy subjects except maximum wall thickness. In volunteers, all ICCs of the age group of ≥50 years were equal to or higher than that of the age group of < 50 years. Normalized wall index and mean and maximum wall thickness were significantly larger in the age group of ≥50 years. To detect 5% - 20% difference between placebo and treatment groups, normalized wall index requires the smallest sample size while lumen volume requires the highest sample size. CONCLUSIONS: Whole-brain 3D IVW CMR is a reliable imaging method for the quantification of intracranial vessel dimensions and could potentially be useful for monitoring plaque progression and regression.

Whole-brain vessel wall MRI: A parameter tune-up solution to improve the scan efficiency of three-dimensional variable flip-angle turbo spin-echo.

PURPOSE: To propose and evaluate a parameter tune-up solution to expedite a three-dimensional (3D) variable-flip-angle turbo spin-echo (TSE) sequence for whole-brain intracranial vessel wall (IVW) imaging. MATERIALS AND METHODS: Elliptical k-space sampling and prolonged echo train length (ETL), were used to expedite a 3D variable-flip-angle TSE-based sequence. To compensate for the potential loss in vessel wall signal, optimal combination of prescribed T2 and ETL was experimentally investigated on 22 healthy volunteers at 3 Tesla. The optimized protocol (7-8 min) was then compared with a previous protocol (reference protocol, 11-12 min) in terms of signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), vessel wall sharpness, and wall delineation quality on a 4-point scale (0:poor; 3:excellent) in 10 healthy volunteers. A pilot study of five patients was performed and lesion delineation score was used to demonstrate the diagnostic quality. RESULTS: A protocol with ETL = 52 and prescribed T2 = 170 ms was deemed an optimized one, which, compared with the reference protocol, provided significantly improved wall SNR (12.0 ± 1.3 versus 10.0 ± 1.1; P = 0.002), wall-lumen CNR (9.7 ± 1.2 versus 8.0 ± 0.9; P = 0.002), wall-CSF CNR (2.8 ± 1.0 versus 1.7 ± 1.0; P = 0.026), similar vessel wall sharpness at both inner (1.59 ± 0.18 versus 1.58 ± 0.14, P = 0.87) and outer (1.71 ± 0.25 versus 1.83 ± 0.30; P = 0.18) boundaries, and comparable vessel wall delineation score for individual segments (1.95-3; P > 0.06). In all patients, atherosclerotic plaques (10) or wall dissection (5) were identified with a delineation score of 3 or 2. CONCLUSION: A parameter tune-up solution can accelerate 3D variable-flip-angle TSE acquisitions, particularly allowed for expedited whole-brain IVW imaging with preserved wall delineation quality. LEVEL OF EVIDENCE: 2. Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:751-757.

Reproduction of ICP Waveform Changes in a Mathematical Model of the Cerebrospinal Circulatory System.

This study describes the establishment of a model of cerebral blood flow dynamics using cerebral blood flow velocity and intracranial pressure waveforms.

Remote Ischemic Conditioning Alters Methylation and Expression of Cell Cycle Genes in Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND AND PURPOSE: Remote ischemic conditioning (RIC) is a phenomenon in which short periods of nonfatal ischemia in 1 tissue confers protection to distant tissues. Here we performed a longitudinal human pilot study in patients with aneurysmal subarachnoid hemorrhage undergoing RIC by limb ischemia to compare changes in DNA methylation and transcriptome profiles before and after RIC. METHODS: Thirteen patients underwent 4 RIC sessions over 2 to 12 days after rupture of an intracranial aneurysm. We analyzed whole blood transcriptomes using RNA sequencing and genome-wide DNA methylomes using reduced representation bisulfite sequencing, both before and after RIC. We tested differential expression and differential methylation using an intraindividual paired study design and then overlapped the differential expression and differential methylation results for analyses of functional categories and protein-protein interactions. RESULTS: We observed 164 differential expression genes and 3493 differential methylation CpG sites after RIC, of which 204 CpG sites overlapped with 103 genes, enriched for pathways of cell cycle (P<3.8×10(-4)) and inflammatory responses (P<1.4×10(-4)). The cell cycle pathway genes form a significant protein-protein interaction network of tightly coexpressed genes (P<0.00001). CONCLUSIONS: Gene expression and DNA methylation changes in aneurysmal subarachnoid hemorrhage patients undergoing RIC are involved in coordinated cell cycle and inflammatory responses.

Early Loss of Immediate Reperfusion While Stent Retriever in Place Predicts Successful Final Reperfusion in Acute Ischemic Stroke Patients.

BACKGROUND AND PURPOSE: Degree of stent retriever engagement with target thrombi may be reflected by (1) immediate reperfusion (IR) on first deployment, indicating displacement of clot toward the vessel wall, and (2) by early loss of IR (ELOIR), indicating penetration of retriever struts through the thrombus. The relation of these early findings to final reperfusion and clinical outcomes has not been well delineated. METHODS: We investigated IR and ELOIR in patients undergoing stent retriever mechanical thrombectomy at an academic medical center between March 2012 and June 2014. RESULTS: Among 56 patients, IR itself was not associated with final successful reperfusion, which occurred in 66.7% of IR patients and 71.4% of non-IR patients (P=0.999). However, ELOIR was associated with a higher rate of final successful reperfusion (92% versus 44%; P=0.046). Patients with ELOIR had a higher nominal rate of final favorable outcome (42% versus 22%; P=0.64). CONCLUSIONS: ELOIR during the embedding period after deployment of stent retrievers is associated with successful final reperfusion, likely because of greater thrombus engagement with the stent retriever. ELOIR may be a useful finding to guide duration of embedding time in clinical practice and design of novel stent retrievers.

An integrated, ontology-driven approach to constructing observational databases for research.

The electronic health record (EHR) contains a diverse set of clinical observations that are captured as part of routine care, but the incomplete, inconsistent, and sometimes incorrect nature of clinical data poses significant impediments for its secondary use in retrospective studies or comparative effectiveness research. In this work, we describe an ontology-driven approach for extracting and analyzing data from the patient record in a longitudinal and continuous manner. We demonstrate how the ontology helps enforce consistent data representation, integrates phenotypes generated through analyses of available clinical data sources, and facilitates subsequent studies to identify clinical predictors for an outcome of interest. Development and evaluation of our approach are described in the context of studying factors that influence intracranial aneurysm (ICA) growth and rupture. We report our experiences in capturing information on 78 individuals with a total of 120 aneurysms. Two example applications related to assessing the relationship between aneurysm size, growth, gene expression modules, and rupture are described. Our work highlights the challenges with respect to data quality, workflow, and analysis of data and its implications toward a learning health system paradigm.

Characterization of the relationship between intracranial pressure and electroencephalographic monitoring in burst-suppressed patients.

BACKGROUND: The objective of this study is to characterize the relationship between ICP and EEG METHODS: Simultaneous ICP and EEG data were obtained from burst-suppressed patients and segmented by EEG bursts. Segments were categorized as increasing/decreasing and peak/valley to investigate relationship between ICP changes and EEG burst duration. A generalized ICP response was obtained by averaging all segments time-aligned at burst onsets. A vasodilatation index (VDI) was derived from the ICP pulse waveform and calculated on a sliding interval to investigate cerebrovascular changes post-burst. RESULTS: Data from two patients contained 309 bursts. 246 ICP segments initially increased, of which 154 peaked. 63 ICP segments decreased, and zero reached a valley. The change in ICP (0.54 ± 0.85 mmHg) was significantly correlated with the burst duration (p < 0.001). Characterization of the ICP segments showed a peak at 8.1 s and a return to baseline at 14.7 s. The VDI for increasing segments was significantly elevated (median 0.56, IQR 0.31, p < 0.001) and correlated with burst duration (p < 0.001). CONCLUSIONS: Changes in the ICP and pulse waveform shape after EEG burst suggest that these signals can be related within the context of neurovascular coupling. SIGNIFICANCE: Existence of a physiological relationship between ICP and EEG may allow the study of neurovascular coupling in acute brain injury patients.

Symptomatic intracerebral hemorrhage in proximal and distal medium middle cerebral artery occlusion patients treated with mechanical thrombectomy.

BACKGROUND: Acute ischemic stroke (AIS) caused by distal medium vessel occlusions (DMVOs) represents a significant proportion of overall stroke cases. While intravenous thrombolysis (IVT) has been a primary treatment, advancements in endovascular procedures have led to increased use of mechanical thrombectomy (MT) in DMVO stroke patients. However, symptomatic intracerebral hemorrhage (sICH) remains a critical complication of AIS, particularly after undergoing intervention. This study aims to identify factors associated with sICH in DMVO stroke patients undergoing MT. METHODS: This retrospective analysis utilized data from the Multicenter Analysis of Distal Medium Vessel Occlusions: Effect of Mechanical Thrombectomy (MAD-MT) registry, involving 37 centers across North America, Asia, and Europe. Middle cerebral artery (MCA) DMVO stroke patients were included. The primary outcome measured was sICH, as defined per the Heidelberg Bleeding Classification. Univariable and multivariable logistic regression were used to identify factors independently associated with sICH. RESULTS: Among 1708 DMVO stroke patients, 148 (8.7%) developed sICH. Factors associated with sICH in DMVO patients treated with MT included older age (adjusted odds ratio (aOR) 1.01, 95% confidence interval (95% CI) 1.00 to 1.03, P=0.048), distal occlusion site (M3, M4) compared with medium occlusions (M2) (aOR 1.71, 95% CI 1.07 to 2.74, P=0.026), prior use of antiplatelet drugs (aOR 2.06, 95% CI 1.41 to 2.99, P<0.001), lower Alberta Stroke Program Early CT Scores (ASPECTS) (aOR 0.75, 95% CI 0.66 to 0.84, P<0.001), higher preoperative blood glucose level (aOR 1.00, 95% CI 1.00 to 1.01, P=0.012), number of passes (aOR 1.27, 95% CI 1.15 to 1.39, P<0.001), and successful recanalization (Thrombolysis In Cerebral Infarction (TICI) 2b-3) (aOR 0.43, 95% CI 0.28 to 0.66, P<0.001). CONCLUSION: This study provides novel insight into factors associated with sICH in patients undergoing MT for DMVO, emphasizing the importance of age, distal occlusion site, prior use of antiplatelet drugs, lower ASPECTS, higher preoperative blood glucose level, and procedural factors such as the number of passes and successful recanalization. Pending confirmation, consideration of these factors may improve personalized treatment strategies.