Failure of Therapeutic Anticoagulation in COVID-19 Patients With Acute Ischemic Stroke. A Retrospective Multicenter Study.

Background: Acute ischemic stroke (AIS) is a possible complication of coronavirus disease 2019 (COVID-19) infection. Although peculiar clinical features and underlying specific mechanisms of thrombogenesis have been suggested so far, there is no consensus on the appropriate vascular preventive drug regimen in patients with COVID-19. Aim and Methods: From a larger clinical series of consecutive acute ischemic strokes related to COVID-19 admitted to three cerebrovascular units in Northern Italy, herein, we describe the clinical features of a subgroup of patients in whom stroke occurred despite therapeutic anticoagulation. Results: A total of seventeen/80 AIS related to COVID-19 (21.2%) occurred in anticoagulated patients. Although no blood level was available for Direct Oral AntiCoagulant, the drug dosage was appropriate according to guidelines. Their National Institute of Health Stroke Scale (NIHSS) at admission was 12.0 (SD = 7.4) and 58.8% of them had evidence of large vessel occlusion. The case fatality rate was as high as 64.7%. Discussion and Conclusions: The occurrence of an anticoagulation failure seems to be increased in the setting of COVID-19 infection, with worse clinical outcomes if compared to non-COVID-19 related ischemic strokes. We discuss the diagnostic and therapeutic implications of such evidence, suggesting that some arterial thrombotic complications might be either resistant to or independent of the anticoagulation effect.

Imaging markers of intracerebral hemorrhage expansion in patients with unclear symptom onset.

BACKGROUND: Hematoma expansion (HE) is common and associated with poor outcome in intracerebral hemorrhage (ICH) with unclear symptom onset (USO). AIMS: We tested the association between non-contrast computed tomography (NCCT) markers and HE in this population. METHODS: Retrospective analysis of patients with primary spontaneous ICH admitted at five centers in the United States and Italy. Baseline NCCT was analyzed for presence of the following markers: intrahematoma hypodensities, heterogeneous density, blend sign, and irregular shape. Variables associated with HE (hematoma growth > 6 mL and/or > 33% from baseline to follow-up imaging) were explored with multivariable logistic regression. RESULTS: Of 2074 patients screened, we included 646 subjects (median age = 75, 53.9% males), of whom 178 (27.6%) had HE. Hypodensities (odds ratio (OR) = 2.67, 95% confidence interval (CI) = 1.79-3.98), heterogeneous density (OR = 2.16, 95% CI = 1.46-3.21), blend sign (OR = 2.28, 95% CI = 1.38-3.75) and irregular shape (OR = 1.82, 95% CI = 1.21-2.75) were independently associated with a higher risk of HE, after adjustment for confounders (ICH volume, anticoagulation, and time from last seen well (LSW) to NCCT). Hypodensities had the highest sensitivity for HE (0.69), whereas blend sign was the most specific marker (0.90). All NCCT markers were more frequent in early presenters (time from LSW to NCCT ⩽ 6 h, n = 189, 29.3%), and more sensitive in this population as well (hypodensities had 0.77 sensitivity). CONCLUSION: NCCT markers are associated with HE in ICH with USO. These findings require prospective replication and suggest that NCCT features may help the stratification of HE in future studies on USO patients.

Imaging features and ultraearly hematoma growth in intracerebral hemorrhage associated with COVID-19.

PURPOSE: Intracerebral hemorrhage (ICH) is an uncommon but deadly event in patients with COVID-19 and its imaging features remain poorly characterized. We aimed to describe the clinical and imaging features of COVID-19-associated ICH. METHODS: Multicenter, retrospective, case-control analysis comparing ICH in COVID-19 patients (COV19 +) versus controls without COVID-19 (COV19 -). Clinical presentation, laboratory markers, and severity of COVID-19 disease were recorded. Non-contrast computed tomography (NCCT) markers (intrahematoma hypodensity, heterogeneous density, blend sign, irregular shape fluid level), ICH location, and hematoma volume (ABC/2 method) were analyzed. The outcome of interest was ultraearly hematoma growth (uHG) (defined as NCCT baseline ICH volume/onset-to-imaging time), whose predictors were explored with multivariable linear regression. RESULTS: A total of 33 COV19 + patients and 321 COV19 - controls with ICH were included. Demographic characteristics and vascular risk factors were similar in the two groups. Multifocal ICH and NCCT markers were significantly more common in the COV19 + population. uHG was significantly higher among COV19 + patients (median 6.2 mL/h vs 3.1 mL/h, p = 0.027), and this finding remained significant after adjustment for confounding factors (systolic blood pressure, antiplatelet and anticoagulant therapy), in linear regression (B(SE) = 0.31 (0.11), p = 0.005). This association remained consistent also after the exclusion of patients under anticoagulant treatment (B(SE) = 0.29 (0.13), p = 0.026). CONCLUSIONS: ICH in COV19 + patients has distinct NCCT imaging features and a higher speed of bleeding. This association is not mediated by antithrombotic therapy and deserves further research to characterize the underlying biological mechanisms.

Hematoma Expansion in Intracerebral Hemorrhage With Unclear Onset.

OBJECTIVE: To investigate the prevalence, predictors, and prognostic effect of hematoma expansion (HE) in patients with intracerebral hemorrhage (ICH) with unclear symptom onset (USO). METHODS: We performed a retrospective analysis of patients with primary spontaneous ICH admitted at 5 academic medical centers in the United States and Italy. HE (volume increase >6 mL or >33% from baseline to follow-up noncontrast CT [NCCT]) and mortality at 30 days were the outcomes of interest. Baseline NCCT was also analyzed for presence of hypodensities (any hypodense region within the hematoma margins). Predictors of HE and mortality were explored with multivariable logistic regression. RESULTS: We enrolled 2,165 participants, 1,022 in the development cohort and 1,143 in the replication cohort, of whom 352 (34.4%) and 407 (35.6%) had ICH with USO, respectively. When compared with participants having a clear symptom onset, patients with USO had a similar frequency of HE (25.0% vs 21.9%, p = 0.269 and 29.9% vs 31.5%, p = 0.423). Among patients with USO, HE was independently associated with mortality after adjustment for confounders (odds ratio [OR] 2.64, 95% confidence interval [CI] 1.43-4.89, p = 0.002). This finding was similar in the replication cohort (OR 3.46, 95% CI 1.86-6.44, p < 0.001). The presence of NCCT hypodensities in patients with USO was an independent predictor of HE in the development (OR 2.59, 95% CI 1.27-5.28, p = 0.009) and replication (OR 2.43, 95% CI 1.42-4.17, p = 0.001) population. CONCLUSION: HE is common in patients with USO and independently associated with worse outcome. These findings suggest that patients with USO may be enrolled in clinical trials of medical treatments targeting HE.

Subarachnoid Extension Predicts Lobar Intracerebral Hemorrhage Expansion.

Background and Purpose- We investigated whether subarachnoid extension (SAHE) of intracerebral hemorrhage (ICH) is associated with hematoma expansion (HE). Methods- Retrospective analysis of patients with primary spontaneous ICH admitted at 3 academic hospitals in Italy. The study population was divided into a development and a replication cohort. SAHE was rated on baseline noncontrast computed tomography by investigators blinded to clinical data. The main outcome of interest was HE, defined as ICH growth >33% mL and/or >6 mL. Predictors of HE were explored with multivariable logistic regression stratified by ICH location (lobar versus nonlobar). Results- A total of 360 and 192 patients were included in the development and replication cohort, respectively. SAHE was identified with good interrater reliability (K=0.82), and its frequency was 27.8% in the development and 24.5% in the replication cohort. In univariate analysis, HE was more common in patients with SAHE (52.0% versus 27.3%; P<0.001). When controlling for confounders in logistic regression, SAHE was an independent predictor of lobar HE (odds ratio, 6.00 [95% CI, 2.16-16.64]; P=0.001) whereas there was no association with HE in nonlobar ICH (odds ratio, 0.55 [95% CI, 0.17-1.84]; P=0.334). The increased risk of HE in lobar ICH with SAHE was confirmed in the replication cohort (odds ratio, 3.46 [95% CI, 1.07-11.20]; P=0.038). Conclusions- SAHE predicts HE in lobar ICH. This may improve the stratification of HE risk in clinical practice or future trials targeting HE. Further research is needed to confirm our findings and characterize the underlying biological mechanisms.

Validation and Comparison of Noncontrast CT Scores to Predict Intracerebral Hemorrhage Expansion.

BACKGROUND AND PURPOSE: The BAT, BRAIN, and HEP scores have been proposed to predict hematoma expansion (HE) with noncontrast computed tomography (NCCT). We sought to validate these tools and compare their diagnostic performance. METHODS: We retrospectively analyzed two cohorts of patients with primary intracerebral hemorrhage. HE expansion was defined as volume growth > 33% or > 6 mL. Two raters analyzed NCCT scans and calculated the scores, blinded to clinical and imaging data. The inter-rater reliability was assessed with the interclass correlation statistic. Discrimination and calibration were calculated with area under the curve (AUC) and Hosmer-Lemeshow χ2 statistic, respectively. AUC comparison between different scores was explored with DeLong test. We also calculated the sensitivity, specificity, positive, and negative predictive values of the dichotomized scores with cutoffs identified with the Youden's index. RESULTS: A total of 230 subjects were included, of whom 86 (37.4%) experienced HE. The observed AUC for HE were 0.696 for BAT, 0.700 for BRAIN, and 0.648 for HEP. None of the scores had a significantly superior AUC compared with the others (all p > 0.4). All the scores had good calibration (all p > 0.3) and good-to-excellent inter-rater reliability (interclass correlation > 0.8). BAT ≥ 3 showed the highest specificity (0.81), whereas BRAIN ≥ 6 had the highest sensitivity (0.76). CONCLUSIONS: The BAT, BRAIN, and HEP scores can predict HE with acceptable discrimination and require just a baseline NCCT scan. These tools may be used to stratify the risk of HE in clinical practice or randomized controlled trials.

Comparison of perihematomal perfusion in deep and lobar intracerebral hemorrhage.

PURPOSE: Hypoperfusion in the perihematomal rim is common in acute intracerebral hemorrhage (ICH) but its determinants remain incompletely characterized. Despite known biological differences between deep and lobar ICH, the association between ICH location and cerebral perfusion has not been investigated. We tested the hypothesis that perihematomal perfusion differs between deep and lobar ICH. METHODS: Prospectively collected cohort of subjects with primary spontaneous ICH undergoing CT perfusion on admission. Cerebral blood flow (CBF), blood volume (CBV), and mean transit time (MTT) were measured in the manually outlined perihematomal low-density area. The association between perihematomal perfusion and ICH location was explored with multivariable linear regression. RESULTS: A total of 155 patients were enrolled (59 with a lobar bleeding). In univariate analysis, median perihematomal CBF and CBV were lower in lobar ICH compared with deep ICH (23.8 vs 33.4 mL/100 g/min, p = 0.001 and 1.7 vs 2.3 mL/100 g, p = 0.001, respectively). Lobar ICH location remained inversely associated with CBF (ß = - 0.17, p = 0.038) and CBV (ß = - 0.19, p = 0.023) after adjustment for confounders in linear regression. CONCLUSION: Lobar ICH location is inversely related with perihematomal CBF and CBV. Further studies are needed to confirm this association and define the underlying biological mechanisms.