Repeated Mechanical Endovascular Thrombectomy for Recurrent Large Vessel Occlusion: A Multicenter Experience.

BACKGROUND AND PURPOSE: Mechanical thrombectomy (MT) is now the standard of care for large vessel occlusion (LVO) stroke. However, little is known about the frequency and outcomes of repeat MT (rMT) for patients with recurrent LVO. METHODS: This is a retrospective multicenter cohort of patients who underwent rMT at 6 tertiary institutions in the United States between March 2016 and March 2020. Procedural, imaging, and outcome data were evaluated. Outcome at discharge was evaluated using the modified Rankin Scale. RESULTS: Of 3059 patients treated with MT during the study period, 56 (1.8%) underwent at least 1 rMT. Fifty-four (96%) patients were analyzed; median age was 64 years. The median time interval between index MT and rMT was 2 days; 35 of 54 patients (65%) experienced recurrent LVO during the index hospitalization. The mechanism of stroke was cardioembolism in 30 patients (56%), intracranial atherosclerosis in 4 patients (7%), extracranial atherosclerosis in 2 patients (4%), and other causes in 18 patients (33%). A final TICI recanalization score of 2b or 3 was achieved in all 54 patients during index MT (100%) and in 51 of 54 patients (94%) during rMT. Thirty-two of 54 patients (59%) experienced recurrent LVO of a previously treated artery, mostly the pretreated left MCA (23 patients, 73%). Fifty of the 54 patients (93%) had a documented discharge modified Rankin Scale after rMT: 15 (30%) had minimal or no disability (modified Rankin Scale score ≤2), 25 (50%) had moderate to severe disability (modified Rankin Scale score 3-5), and 10 (20%) died. CONCLUSIONS: Almost 2% of patients treated with MT experience recurrent LVO, usually of a previously treated artery during the same hospitalization. Repeat MT seems to be safe and effective for attaining vessel recanalization, and good outcome can be expected in 30% of patients.

CTA-for-All: Impact of Emergency Computed Tomographic Angiography for All Patients With Stroke Presenting Within 24 Hours of Onset.

Background and Purpose- We sought to evaluate the impact of a Computed Tomographic Angiography (CTA) for All emergency stroke imaging protocol on outcome after large vessel occlusion (LVO). Methods- On July 1, 2017, the Henry Ford Health System implemented the policy of performing CTA and noncontrast computed tomography together as an initial imaging study for all patients with acute ischemic stroke (AIS) presenting within 24 hours of last known well, regardless of baseline National Institutes of Health Stroke Scale score. Previously, CTA was reserved for patients presenting within 6 hours with a National Institutes of Health Stroke Scale score ≥6. We compared treatment processes and outcomes between patients with AIS admitted 1 year before (n=388) and after (n=515) protocol implementation. Results- After protocol implementation, more AIS patients underwent CTA (91% versus 61%; P<0.001) and had CTA performed at the same time as the initial noncontrast computed tomography scan (78% versus 35%; P<0.001). Median time from emergency department arrival to CTA was also shorter (29 [interquartile range, 16-53] versus 43 [interquartile range, 29-112] minutes; P<0.001), more cases of LVO were detected (166 versus 96; 32% versus 25% of all AIS; P=0.014), and more mechanical thrombectomy procedures were performed (108 versus 68; 21% versus 18% of all AIS; P=0.196). Among LVO patients who presented within 6 hours of last known well, median time from last known well to mechanical thrombectomy was shorter (3.5 [interquartile range, 2.8-4.8] versus 4.1 [interquartile range, 3.3-5.6] hours; P=0.038), and more patients were discharged with a favorable outcome (Glasgow Outcome Scale 4-5, 53% versus 37%; P=0.029). The odds of having a favorable outcome after protocol implementation was not significant (odds ratio, 1.84 [95% CI, 0.98-3.45]; P=0.059) after controlling for age and baseline National Institutes of Health Stroke Scale score. Conclusions- Performing CTA and noncontrast computed tomography together as an initial assessment for all AIS patients presenting within 24 hours of last known well improved LVO detection, increased the mechanical thrombectomy treatment population, hastened intervention, and was associated with a trend toward improved outcome among LVO patients presenting within 6 hours of symptom onset.

Circle of Willis Collateral During Temporary Internal Carotid Artery Occlusion I: Observations From Digital Subtraction Angiography.

INTRODUCTION: Impaired collateral circulation can lead to stroke during carotid endarterectomy. Carotid stump pressure (CSP) is used as a surrogate measure of collateral flow. The objective was to determine whether anatomical features obtained from digital subtraction angiography correlate with CSP during temporary internal carotid artery occlusion. The second objective was to use these features in combination to predict CSP. METHODS: Digital subtraction angiographies from 102 patients obtained before endarterectomy were reviewed for anatomical variables including: degree of ipsilateral and contralateral carotid artery stenosis; patency of the anterior communicating artery; presence of cross-flow into ipsilateral middle cerebral artery branches; and size (< or ≥1 mm calibre) of the ipsilateral proximal anterior cerebral (A1), the contralateral A1, and the ipsilateral posterior communicating arteries. At surgery, systemic mean arterial pressure (MAP) and CSP were recorded. Multiple regression analysis was used to assess for anatomical features significantly associated with CSP. A "predicted CSP" equation was applied to 54 subsequent patients and correlated with measured CSP. RESULTS: Variables correlating with CSP included MAP (p=0.001); the presence of severe contralateral carotid stenosis (p=0.002); patency of the anterior communicating artery (p=0.013); and the size of the contralateral A1 segment (p=0.029). Angiographic cross-flow, ipsilateral A1 size, and ipsilateral posterior communicating artery size were not significant. Predicted CSP correlated significantly with measured CSP (p<0.0001; R 2=0.34). CONCLUSIONS: Anatomical features and systemic MAP are associated with carotid stump pressure during internal carotid artery occlusion and account for a significant amount of its variation.

Case Series: Long segment extra-arachnoid fluid collections: Role of dynamic CT myelography in diagnosis and treatment planning.

We report five patients in whom spinal MRI revealed extra-arachnoid fluid collections. These spinal fluid collections most likely resulted from accumulation of cerebrospinal fluid (CSF) from a dural leak. The patients presented with either compressive myelopathy due to the cyst or superficial siderosis (SS). All of these fluid collections were long segment, and MRI demonstrated the fluid collections but not the exact site of leak. Dynamic CT myelogram demonstrated the site of leak and helped in the management of these complicated cases. Moreover, we also found that the epicenter of the fluid collection on MRI was different from the location of the leak on a dynamic CT myelogram. Knowledge of these associations can be helpful when selecting the imaging studies to facilitate diagnosis and treatment.

Creating accountable care for carotid angioplasty and stenting: A multidisciplinary carotid revascularization board.

BACKGROUND: We tested the feasibility of a mandated multidisciplinary carotid revascularization board (MDCB) to review, approve and monitor all carotid artery and stenting (CAS) procedures and outcomes at our institution. METHODS: The board was composed of vascular surgeons, cardiologists, interventional neuroradiologists, neurosurgeons, and neurologists, who met weekly to facilitate an evidence-based, consensus recommendation to ensure appropriate CAS referral. RESULTS: The board successfully reviewed and continues to review and approve all CAS procedures at our center. Of the 69 patients considered high risk for standard surgical treatment, 42 patients were symptomatic and 27 patients were asymptomatic. Their mean age was 70.5-year-old and the median degree of stenosis was 79%. In the 74 procedures, periprocedural complications occurred at the following rates: 2.7% death, 2.7% major stroke, 2.7% minor stroke, and 2.7% myocardial infarction (MI) within 30 days of the procedure. At 1 year the primary endpoints of ipsilateral stroke and neurovascular-related death were observed in 8.1% and 2.7% of the patients, respectively. At mean follow-up of 21 months, 18.8% of the patients (13/69) had died (including all causes), and 14.5% (10/69) experienced stroke (including nontarget strokes). Target vessel revascularization was needed in 2.9% patients. CONCLUSIONS: A mandated multidisciplinary carotid revascularization board MDCB is feasible and potentially advantageous in real clinical practice. It establishes a model for accountable care by providing a mechanism for institutional oversight, credentialing operators, quality review, standardizing care, cost containment and eliminating the "subspecialty silo mentality."