Large Vessel Occlusion in Patients With Minor Ischemic Stroke in a Population-Based Study. The Dijon Stroke Registry

Introduction:Strategy for the acute management of minor ischemic stroke (IS) with large vessel occlusion (LVO) is under debate, especially the benefits of mechanical thrombectomy. The frequency of minor IS with LVO among overall patients is not well established. This study aimed to assess the proportion of minor IS and to depict characteristics of patients according to the presence of LVO in a comprehensive population-based setting.Methods:Patients with acute IS were prospectively identified among residents of Dijon, France, using a population-based registry (2013–2017). All arterial imaging exams were reviewed to assess arterial occlusion. Minor stroke was defined as that with a National Institutes of Health Stroke Scale (NIHSS) score of <6. Proportion of patients with LVO was estimated in the minor IS population. The clinical presentation of patients was compared according to the presence of an LVO.Results:Nine hundred seventy-one patients were registered, including 582 (59.9%) patients with a minor IS. Of these patients, 23 (4.0%) had a LVO. Patients with minor IS and LVO had more severe presentation [median 3 (IQR 2–5) vs. 2 (IQR 1–3), p = 0.001] with decreased consciousness (13.0 vs. 1.6%, p<0.001) and cortical signs (56.5 vs. 30.8%, p = 0.009), especially aphasia (34.8 vs. 15.4%, p = 0.013) and altered item level of consciousness (LOC) questions (26.1 vs. 11.6%, p = 0.037). In multivariable analyses, only NIHSS score (OR = 1.45 per point; 95% CI: 1.11–1.91, p = 0.007) was associated with proximal LVO in patients with minor IS.Conclusion:Large vessel occlusion (LVO) in minor stroke is non-exceptional, and our findings highlight the need for emergency arterial imaging in any patients suspected of acute stroke, including those with minor symptoms because of the absence of obvious predictors of proximal LVO.

Diagnostic Performance of Ankle-Brachial Pressure Index in Lower Extremity Arterial Disease

Introduction Ankle-brachial pressure indices (ABIs) continue to form the basis of diagnostics for lower extremity arterial disease (LEAD). However, there remains a paucity of data to support its accuracy. This study aims to evaluate its diagnostic sensitivity and specificity using established arterial-imaging modalities as a benchmark. Methods In this retrospective study, a regional, prospectively maintained, vascular laboratory database was interrogated to identify referred patients with arterial disease who underwent concomitant assessment with ABI and lower limb arterial duplex ultrasound (DUS). Duplex acted as the reference standard. Those who had peripheral computed tomography angiogram (CTA) within 3 months of initial assessment were included in a subgroup analysis to correlate ABI with CTA. The primary end point was the sensitivity and specificity of ABI compared with DUS as the reference standard. Results Concomitant assessment was performed in 438 limbs (250 patients) over a 27-month period. The ABI was normal (0.9 to 1.4) in 196 limbs (44.9%) and abnormal in the remaining 241 limbs (55.1%). False-positive results occurred in 83 out of 241 limbs (34.4%), and false-negative results occurred in 54 limbs out of 196 (27.5%). True-positive results were 158 out of 241 limbs (65.6%), whereas true-negative results were 142 out of 196 limbs (72.4%). ABI using DUS as a benchmark identified a sensitivity for peripheral artery disease of 72.3% and a specificity of 69.3%. Concomitant CTA imaging was available in 200 limbs. The sensitivity and specificity of ABI correlated with CTA were 65.5 and 68.8%, respectively. Conclusion ABIs have a moderate predictive value in the diagnosis of LEAD. Normal range outcomes cannot be taken to infer the absence of LEAD and, as such, further arterial imaging in the form of DUS or angiography should be strongly considered in those with suspected underlying disease requiring intervention. Further noninvasive tests such as exercise studies or pulse volume waveforms should be considered, if diagnostic uncertainty exists, in those requiring nonoperative intervention and risk factor control.

Abstract P570: Arterial Stenosis in Posterior Reversible Encephalopathy Syndrome

Objectives: Posterior Reversible Encephalopathy Syndrome (PRES) is characterized as reversible vasogenic cerebral edema in a posterior-dominant distribution. Some patients with PRES have diffusion-weighted imaging (DWI) changes on MRI, as well as transient arterial stenosis. We examined the association between arterial stenosis and presence of hemorrhage and MRI-DWI changes in PRES. Methods: We retrospectively identified patients with PRES in electronic health records at a single health system from January 2008 to December 2018. We included patients age 18 years or older with clinical and radiographic evidence of PRES and arterial imaging (CT or MR angiography or digital subtraction angiogram). Any arterial stenosis was noted, with reversibility determined by repeat imaging. Patient characteristics, disease presentation, hospital lengths of stay and discharge dispositions, as well as imaging findings were collected and statistical analysis was used. Results: Of 281 patients with PRES, 169 had arterial imaging. Thirty-two (18.9%) had arterial stenosis and 60% had resolved arterial stenosis on follow-up imaging. Patients with arterial stenosis were younger compared to those without (47 v 55 years, p =0.03), however they did not differ in symptoms of presentation or comorbid conditions. Of note, arterial stenosis was associated with intracerebral hemorrhage[34% with stenosis and 18% without stenosis, p=0.05). However, the presence of MRI DWI lesions did not correlate with arterial stenosis [14/32 (44%) with stenosis, 49/137 (36%) without stenosis, p=0.42]. Among 97 patients with follow-up MRI, the presence of arterial stenosis was not associated with greater FLAIR reversibility. Furthermore, hospital length of stay or discharge disposition was not associated with arterial stenosis in PRES. Conclusions: Arterial stenoses are found in 19% of PRES patients, and most are reversed on follow-up imaging. They are also associated with hemorrhagic PRES, but not with MRI-DWI lesions or degree of FLAIR reversibility.

Abstract WP178: The Presence of Arterial Stenosis in Posterior Reversible Encephalopathy Syndrome

Introduction: Posterior Reversible Encephalopathy Syndrome (PRES) is defined as reversible vasogenic cerebral edema in a characteristic posterior-dominant distribution in patients presenting with focal neurologic findings. It has been shown that some patients with PRES have transient arterial stenosis. Objectives: To determine the prevalence of arterial stenosis in PRES patients and demonstrate if patients with arterial stenosis define a subpopulation within PRES. Methods: We searched patients with PRES in electronic health records at a single health system from January 2008 to December 2018. Inclusion criteria were age 18 years or older with clinical and radiographic evidence of PRES and arterial imaging (CT or MR angiography or cerebral angiogram.) Age, presenting symptoms, comorbid conditions, and imaging findings were compared between those with arterial stenosis and those without. Results: Of 74 patients diagnosed with PRES, 46 had arterial imaging. Arterial stenosis was seen in 28.3% (13/46) of these patients. Stenoses improved in all 4 patients who had followup imaging, 3 with complete resolution. The arterial stenosis group was younger (median age 32 years with arterial stenosis vs 57.5 years without, p= 0.011.) Patients with arterial stenosis did not differ in frequency of presenting symptoms of seizure, encephalopathy, or focal neurologic deficits, nor did they differ in comorbid conditions of hypertension, immune suppression, eclampsia/preeclampsia, or antidepressant use. There were no differences in ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, or frequency of diffusion restriction on MRI between the groups. The occurrence of >50% FLAIR reversibility was less frequent among those with arterial stenosis (40%) than in those without arterial stenosis (81%, p=0.04.) Conclusions: A quarter of patients with PRES had transient arterial stenosis. These patients represent a subgroup within PRES patients who are younger age, but lower frequency of reversibility of parenchymal imaging abnormality.

State-of-the-art pulmonary arterial imaging – Part 2

Although pulmonary embolism is the most common abnormality of the pulmonary artery, there is a broad spectrum of other congenital and acquired pulmonary arterial abnormalities. Multiple imaging modalities are now available to evaluate these abnormalities of the pulmonary arteries. CT and MRI are the most commonly used cross-sectional imaging modalities that provide comprehensive information on several aspects of these abnormalities, including morphology, function, risk-stratification and therapy-monitoring. In this article, we review the role of state-of-the-art pulmonary arterial imaging in the evaluation of non-thromboembolic disorders of pulmonary artery.

State-of-the-art pulmonary arterial imaging – Part 1

The pulmonary arteries are affected by a variety of congenital and acquired abnormalities. Multiple state-of-the art imaging modalities are available to evaluate these pulmonary arterial abnormalities, including computed tomography (CT), magnetic resonance imaging (MRI), echocardiography, nuclear medicine imaging and catheter pulmonary angiography. In part one of this two-part series on state-of-the art pulmonary arterial imaging, we review these imaging modalities, focusing particularly on CT and MRI. We also review the utility of these imaging modalities in the evaluation of pulmonary thromboembolism.