Structural Brain Injury on Brain Magnetic Resonance Imaging in Acute Respiratory Distress Syndrome.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is an acute inflammatory respiratory failure condition that may be associated with brain injury. We aimed to describe the types of structural brain injuries detected by brain magnetic resonance imaging (MRI) among patients with ARDS. METHODS: We retrospectively reviewed and collected data on brain injuries as detected by brain MRI during index hospitalization of all patients with ARDS at a single tertiary center in the United States from January 2010 to October 2018 (pre-COVID era). Structural brain injuries were classified as cerebral ischemia (ischemic infarct and hypoxic-ischemic brain injury) or cerebral hemorrhage (intraparenchymal hemorrhage, cerebral microbleeds, subarachnoid hemorrhage, and subdural hematoma). Descriptive statistics were conducted. RESULTS: Of the 678 patients with ARDS, 66 (9.7%) underwent brain MRI during their ARDS illness. The most common indication for brain MRI was encephalopathy (45.4%), and the median time from hospital admission to MRI was 10 days (interquartile range 4-17). Of 66 patients, 29 (44%) had MRI evidence of brain injury, including cerebral ischemia in 33% (22 of 66) and cerebral hemorrhage in 21% (14 of 66). Among those with cerebral ischemia, common findings were bilateral globus pallidus infarcts (n = 7, 32%), multifocal infarcts (n = 5, 23%), and diffuse hypoxic-ischemic brain injury (n = 3, 14%). Of those with cerebral hemorrhage, common findings were cerebral microbleeds (n = 12, 86%) and intraparenchymal hemorrhage (n = 2, 14%). Patients with ARDS with cerebral hemorrhage had significantly greater use of rescue therapies, including prone positioning (28.6% vs. 5.8%, p = 0.03), inhaled vasodilator (35.7% vs. 11.5%, p = 0.046), and recruitment maneuver (14.3% vs. 0%, p = 0.04). CONCLUSIONS: Structural brain injury was not uncommon among selected patients with ARDS who underwent brain MRI. The majority of brain injuries seen were bilateral globus pallidus infarcts and cerebral microbleeds.

Pearls & Oy-sters: Mitral Annular Calcification as a Cause of Ischemic Stroke: A Case Report.

Evaluation of stroke etiology is an important aspect of stroke care affecting secondary prevention measures. Despite recent advances in diagnostic testing, determining the stroke etiology can remain a challenging task particularly for less common causes of stroke such as mitral annular calcification. This case will review the benefit of histopathologic clot evaluation after thrombectomy to identify uncommon causes of embolic stroke which may change management.

Atrial Fibrillation and Ischemic Stroke: A Clinical Review.

Atrial fibrillation (AF) is an important risk factor for ischemic stroke resulting in a fivefold increased stroke risk and a twofold increased mortality. Our understanding of stroke mechanisms in AF has evolved since the concept of atrial cardiopathy was introduced as an underlying pathological change, with both AF and thromboembolism being common manifestations and outcomes. Despite the strong association with stroke, there is no evidence that screening for AF in asymptomatic patients improves clinical outcomes; however, there is strong evidence that patients with embolic stroke of undetermined source may require long-term monitoring to detect silent or paroxysmal AF. Stroke prevention in patients at risk, assessed by the CHA2DS2-VASc score, was traditionally achieved with warfarin; however, direct oral anticoagulants have solidified their role as safe and effective alternatives. Additionally, left atrial appendage exclusion has emerged as a viable option in patients intolerant of anticoagulation. When patients with AF have an acute stroke, the timing of initiation or resumption of anticoagulation for secondary stroke prevention has to be balanced against the risk of hemorrhagic conversion. Multiple randomized clinical trials are currently underway to determine the best timing for administration of anticoagulants following acute ischemic stroke.

Bloodstream infection is associated with subarachnoid hemorrhage and infectious intracranial aneurysm in left ventricular assist device.

Bloodstream infection is the leading cause of mortality in left ventricular assist device. Bloodstream infection is a risk factor for intracranial hemorrhage. We report three left ventricular assist device recipients who presented with bloodstream infection and developed subarachnoid hemorrhage. Case 1, a 37-year-old male with non-ischemic cardiomyopathy with HeartMate II, presented with confusion and found to have serratia bloodstream infection and left frontal lobe subarachnoid hemorrhage. Cerebral angiogram showed a right M3/M4 branch infectious intracranial aneurysm. He was treated with coil embolization and underwent device exchange. Case 2, a 41-year-old male with non-ischemic cardiomyopathy with HeartMate II presented with confusion and found to have methicillin-resistant staphylococcus aureus bloodstream infection and bilateral frontal convexity subarachnoid hemorrhage. Cerebral angiogram showed left M3 and left A3 infectious intracranial aneurysms, which were treated with antibiotics alone. Case 3, a 58-year-old female with ischemic cardiomyopathy with HeartMate II presented with fever, found to have candida albicans bloodstream infection and a parieto-occipital enhancing lesion concerning for cerebral abscess. Repeat computed tomography brain a week later showed a new right frontal subarachnoid hemorrhage. Cerebral angiogram showed a M4/M5 junction infectious intracranial aneurysm; patient was not a surgical candidate and was transitioned to hospice. This case series emphasizes that left ventricular assist device-associated subarachnoid hemorrhage may be caused by infectious intracranial aneurysms when acute bloodstream infections are present.

Cerebral ischemia and deterioration with lower blood pressure target in intracerebral hemorrhage.

OBJECTIVE: To determine the incidence and predictors of acute cerebral ischemia and neurologic deterioration in intracerebral hemorrhage (ICH) patients after an institutional protocol change in systolic blood pressure (SBP) target from <160 to <140 mm Hg. METHODS: We retrospectively compared persons admitted with primary ICH before and after a protocol change in SBP target from <160 to <140 mm Hg. The primary outcomes were presence of acute cerebral ischemia on MRI completed within 2 weeks of ICH and acute neurologic deterioration. RESULTS: Of 286 persons with primary ICH, 119 underwent MRI and met inclusion criteria. Sixty-two had a target SBP <160 mm Hg (group 1) and 57 had a target SBP <140 mm Hg (group 2). There were no differences between the 2 groups in baseline clinical and radiographic characteristics, but over the first 24 hours of hospitalization, group 2 had lower mean SBP (134 vs 143 mm Hg, p < 0.001) and lower minimum SBP over 72 hours (106 vs 112 mm Hg, p = 0.02). Acute cerebral ischemia was more frequent in group 2 than in group 1 (32% vs 16%; p = 0.047) as was acute neurologic deterioration (19% vs 5%; p = 0.022). A minimum SBP ≤120 mm Hg over 72 hours was associated with cerebral ischemia, while no patient with a minimum SBP ≥130 mm Hg had cerebral ischemia. Acute cerebral ischemia was significantly associated with worse discharge NIH Stroke Scale score, while SBP target was not. CONCLUSIONS: Intensive lowering of SBP <140 mm Hg in acute ICH, particularly allowing SBP <120 mm Hg, is associated with increased remote cerebral ischemic lesions and acute neurologic deterioration.

Magnetic Resonance Imaging Susceptibility-Weighted Imaging Lesion and Contrast Enhancement May Represent Infectious Intracranial Aneurysm in Infective Endocarditis.

BACKGROUND: Infectious intracranial aneurysm (IIA) can complicate infective endocarditis (IE). We aimed to describe the magnetic resonance imaging (MRI) characteristics of IIA. METHODS: We reviewed IIAs among 116 consecutive patients with active IE by conducting a neurological evaluation at a single tertiary referral center from January 2015 to July 2016. MRIs and digital cerebral angiograms (DSA) were reviewed to identify MRI characteristics of IIAs. MRI susceptibility weighted imaging (SWI) was performed to collect data on cerebral microbleeds (CMBs) and sulcal SWI lesions. RESULTS: Out of 116 persons, 74 (63.8%) underwent DSA. IIAs were identified in 13 (17.6% of DSA, 11.2% of entire cohort) and 10 patients with aneurysms underwent MRI with SWI sequence. Nine (90%) out of 10 persons with IIAs had CMB >5 mm or sulcal lesions in SWI (9 in sulci, 6 in parenchyma, and 5 in both). Five out of 8 persons who underwent MRI brain with contrast had enhancement within the SWI lesions. In a multivariate logistic regression analysis, both sulcal SWI lesions (p < 0.001, OR 69, 95% CI 7.8-610) and contrast enhancement (p = 0.007, OR 16.5, 95% CI 2.3-121) were found to be significant predictors of the presence of IIAs. CONCLUSIONS: In the individuals with IE who underwent DSA and MRI, we found that neuroimaging characteristics, such as sulcal SWI lesion with or without contrast enhancement, are associated with the presence of IIA.

Reduction in time to treatment in prehospital telemedicine evaluation and thrombolysis.

OBJECTIVE: To compare the times to evaluation and thrombolytic treatment of patients treated with a telemedicine-enabled mobile stroke treatment unit (MSTU) vs those among patients brought to the emergency department (ED) via a traditional ambulance. METHODS: We implemented a MSTU with telemedicine at our institution starting July 18, 2014. A vascular neurologist evaluated each patient via telemedicine and a neuroradiologist and vascular neurologist remotely assessed images obtained by the MSTU CT. Data were entered in a prospective registry. The evaluation and treatment of the first 100 MSTU patients (July 18, 2014-November 1, 2014) was compared to a control group of 53 patients brought to the ED via a traditional ambulance in 2014. Times were expressed as medians with their interquartile ranges. RESULTS: Patient and stroke severity characteristics were similar between 100 MSTU and 53 ED control patients (initial NIH Stroke Scale score 6 vs 7, p = 0.679). There was a significant reduction of median alarm-to-CT scan completion times (33 minutes MSTU vs 56 minutes controls, p < 0.0001), median alarm-to-thrombolysis times (55.5 minutes MSTU vs 94 minutes controls, p < 0.0001), median door-to-thrombolysis times (31.5 minutes MSTU vs 58 minutes controls, p = 0.0012), and symptom-onset-to-thrombolysis times (97 minutes MSTU vs 122.5 minutes controls, p = 0.0485). Sixteen patients evaluated on MSTU received thrombolysis, 25% of whom received it within 60 minutes of symptom onset. CONCLUSION: Compared with the traditional ambulance model, telemedicine-enabled ambulance-based thrombolysis resulted in significantly decreased time to imaging and treatment.

A Mobile Stroke Treatment Unit for Field Triage of Patients for Intraarterial Revascularization Therapy.

INTRODUCTION: Favorable outcomes in intraarterial therapy (IAT) for acute ischemic stroke (AIS) are related to early vessel recanalization. The mobile stroke treatment unit (MSTU) is an on-site, prehospital, treatment team, laboratory, and CT scanner that reduces time to treatment for intravenous thrombolysis and may also shorten time to IAT. METHODS: Using our MSTU database, we identified patients that underwent IAT for AIS. We compared the key time metrics to historical controls, which included patients that underwent IAT at our institution six months prior to implementation of the MSTU. We further divided the controls into two groups: (1) transferred to our institution for IAT and (2) directly presented to our emergency room and underwent IAT. RESULTS: After 164 days of service, the MSTU transported 155 patients of which 5 underwent IAT. We identified 5 historical controls that were transferred to our center for IAT. Substantial reduction in times including median door to initial CT (12 minute vs. 32 minute), CT to IAT (82 minute vs. 165 minute), and door to MSTU/primary stroke center departure (37 minute vs. 106 minute) were noted among the two groups. Compared to the 6 patients who presented to our institution directly, the MSTU process times were also shorter. CONCLUSION: Our initial experience shows that MSTU may help in early triage and shorten the time to IAT for AIS.