Less thrombolysis in posterior circulation infarction-a necessary evil?

A Two-Step Approach Using the National Health Institutes of Health Stroke Scale Assessed by Paramedics to Enhance Prehospital Stroke Detection: A Case Report and Concept Proposal

Background: Prehospital detection and triage of stroke patients mostly rely on the use of large vessel occlusion prediction scales to decrease onsite time. These quick but simplified scores, though useful, prevent prehospital providers from detecting posterior strokes and isolated symptoms such as limb ataxia or hemianopia. Case report: In the present case, an ambulance was dispatched to a 46-year-old man known for ophthalmic migraines and high blood pressure, who presented isolated visual symptoms different from those associated with his usual migraine attacks. Although the assessment advocated by the prehospital guideline was negative for stroke, the paramedic who assessed the patient was one of the few trained in the National Institutes of Health Stroke Scale assessment. Based on this assessment, the paramedic activated the fast-track stroke alarm and an ischemic stroke in the right temporal lobe was finally confirmed by magnetic resonance imaging. Discussion and conclusions: Current prehospital practice enables paramedics to detect anterior strokes but often limits the detection of posterior events or more subtle symptoms. Failure to identify such strokes delay or even forestall the initiation of thrombolytic therapy, thereby worsening patient outcomes. We therefore advocate a two-step prehospital approach: first, to avoid unnecessary delays, the prehospital stroke assessment should be carried out using a fast large vessel occlusion prediction scale; then, if this assessment is negative but potential stroke symptoms are present, a full National Institutes of Health Stroke Scale assessment could be performed to detect neurological deficits overlooked by the fast stroke scale.

Intravenous Thrombolysis in Posterior versus Anterior Circulation Stroke: Clinical Outcome Differs Only in Patients with Large Vessel Occlusion

The safety and efficacy of intravenous thrombolysis (IVT) are well established in anterior circulation stroke (ACS) but are much less clear for posterior circulation stroke (PCS). The aim of this study was to evaluate the occurrence of parenchymal hematoma (PH) and 3-month clinical outcomes after IVT in PCS and ACS. In an observational, cohort multicenter study, we analyzed data from ischemic stroke patients treated with IVT prospectively collected in the SITS (Safe Implementation of Treatments in Stroke) registry in the Czech Republic between 2004 and 2018. Out of 10,211 patients, 1166 (11.4%) had PCS, and 9045 (88.6%) ACS. PH was less frequent in PCS versus ACS patients: 3.6 vs. 5.9%, odds ratio (OR) = 0.594 in the whole set, 4.4 vs. 7.8%, OR = 0.543 in those with large vessel occlusion (LVO), and 2.2 vs. 4.7%, OR = 0.463 in those without LVO. At 3 months, PCS patients compared with ACS patients achieved more frequently excellent clinical outcomes (modified Rankin scale [mRS] 0-1: 55.5 vs. 47.6%, OR = 1.371 in the whole set and 49.2 vs. 37.6%, OR = 1.307 in those with LVO), good clinical outcomes (mRS 0-2: 69.9 vs. 62.8%, OR = 1.377 in the whole set and 64.5 vs. 50.5%, OR = 1.279 in those with LVO), and had lower mortality (12.4 vs. 16.6%, OR = 0.716 in the whole set and 18.4 vs. 25.5%, OR = 0.723 in those with LVO) (p < 0.05 in all cases). In PCS versus ACS patients, an extensive analysis showed a lower risk of PH both in patients with and without LVO, more frequent excellent and good clinical outcomes, and lower mortality 3 months after IVT in patients with LVO.

Posterior Circulation Stroke Patients Receive Less Reperfusion Therapy Because of Late Arrival and Relative Contraindications: A Retrospective Study

BACKGROUND

Reperfusion treatment (RT) is administered to individuals with posterior circulation strokes (PCS) later and less frequently. We aimed to study the impact of demographic and clinical factors on the decision for RT in PCS.

METHODS

We conducted a retrospective analysis of the data from 500 subjects admitted to the tertiary stroke centre's emergency department between 2018 and 2020 due to PCS. Demographic and clinical factors were analysed among three groups: the RT group, the group with no RT because of absolute contraindications (ACI), and the group with no RT because of relative contraindications (RCI).

RESULTS

Of the patients, 202 (40.3%) were female. The median NIHSS was four (4), and the subjects' median age was 69 (18). RT was performed on 120 (24%) subjects. FAST symptoms (OR-5.62, 95% CI [2.90-12.28]) and higher NIHSS (OR-1.13, 95% CI [1.09-1.18]) at presentation, atrial fibrillation (OR-1.56, 95% CI [1.02-2.38]), hypertension (OR-2.19, 95% CI [1.17-4.53]) and diabetes (OR-1.70, 95% CI [1.06-2.71]) increased the chance of RT. Late arrival was the most prevalent ACI for 291 (58.2%) patients. FAST-negative subjects (OR-2.92, 95% CI [1.84-4.77]) and males (OR-1.58, 95% CI [1.11-2.28]) had a higher risk of arriving late. Because of RCI, 50 (10%) subjects did not receive RT; the majority were above 80 and had NIHSS ≤ 5. Subjects with RCI who received the RT had a higher NIHSS (4 vs. 3, p < 0.001), higher hypertension (59 (92.2%) vs. 35 (77.8%), p = 0.032) and heart failure (23 (35.9%) vs. 7 (15.6%), p = 0.018) prevalence. There was a trend for less RT in females with RCI.

CONCLUSIONS

Late arrival was the most common barrier to RT, and the male gender increased this risk. because of relative contraindications, 10% of subjects were not considered for RT. The presence of FAST symptoms, vascular risk factors, and a higher NIHSS increased the chance of RT.

What Is the Evidence for Endovascular Thrombectomy in Posterior Circulation Stroke?

Posterior circulation infarcts comprise approximately 25% of ischemic strokes but are less often treated with recanalization therapy and have longer treatment delays compared with anterior circulation strokes. Among posterior circulation strokes, basilar artery occlusion is associated with the most severe deficits and the worst prognosis. Endovascular thrombectomy is a standard of care for patients with anterior circulation large vessel occlusion, but not until recently were the first randomized controlled trials on endovascular thrombectomy in basilar artery occlusion published. Two of the trials were neutral, whereas two others showed better functional outcome after thrombectomy up to 24 hours of symptom onset compared with best medical treatment, which in most cases had low rates of intravenous thrombolysis. According to observational data, thrombectomy seems to be safe also in isolated posterior cerebral artery occlusions and might be an option for selected patients, even if its outcome benefit is yet to be demonstrated.

What guides decision-making on intravenous thrombolysis in acute vestibular syndrome and suspected ischemic stroke in the posterior circulation?

Intravenous thrombolysis (IVT) is rarely performed in dizzy patients with acute vestibular syndrome (AVS) or acute imbalance (AIS) even if posterior circulation stroke (PCS) is suspected. Decision-making may be affected by uncertainties in discriminating central from peripheral vestibulopathy or concerns of IVT-related harm, particularly intracerebral hemorrhage (ICH), but related studies are missing. Using an in-house register of dizzy patients coming to the emergency room, we identified 29 AVS/AIS patients who presented within 4.5 h after onset, revealed clinical signs indicative of PCS (central oculomotor signs, mild focal abnormalities), and had non-contrast computed tomography (NCCT). Patients treated with IVT (n = 15) were compared to NoIVT patients (n = 14) with regard to clinical and imaging (including perfusion computed tomography, CTP) parameters, occurrence of ICH and short-term clinical outcome (NIHSS improvement; ability to walk independently). IVT and NoIVT patients did not differ in baseline characteristics, central oculomotor signs, or clinical outcome. IVT patients more often exhibited disabling vestibular symptoms (severe dizziness/vertigo, inability to stand unsupported) and focal abnormalities than NoIVT patients. There was no ICH in either group. CTP was performed in 0% of NoIVT versus 80% of IVT patients, seven of twelve revealing posterior circulation hypoperfusion. Comparison of initial hypoperfusion (CTP) and final stroke (NCCT) revealed IVT-related benefit (smaller lesion) in three of seven IVT patients. In AVS/AIS patients with suspected PCS, disabling vestibular symptoms, focal neurological deficits, and hypoperfusion on CTP seem to direct decision-making pro IVT. In our small cohort, there were no significant IVT-related clinical benefits, no IVT-related ICHs, and salvage of brain tissue in some patients.

"Invisible" visual impairments. A qualitative study of stroke survivors` experience of vision symptoms, health services and impact of visual impairments

BACKGROUND

Visual impairments (VIs) have a negative impact on life and affect up to 60% of stroke survivors. Despite this, VIs are often overlooked. This paper explores how persons with VIs experience vision care within stroke health services and how VIs impact everyday life the first 3 months post stroke.

METHODS

Individual semi-structured interviews were conducted with 10 stroke survivors 3 months post stroke, and analyzed using qualitative content analysis.

RESULTS

The main theme, "Invisible" visual impairments, represents how participants experience VIs as an unknown and difficult symptom of stroke and that the lack of attention and appropriate visual care leads to uncertainty about the future. VIs were highlighted as a main factor hindering the participants living life as before. The lack of acknowledgement, information, and systematic vision rehabilitation leads to feelings of being unsupported in the process of coping with VIs.

CONCLUSION

VIs are unknown symptoms pre stroke and sequelas after stroke that significantly affect everyday life. VIs and vision rehabilitation needs more attention through all phases of stroke health services. We request a greater awareness of VIs as a presenting symptom of stroke, and that visual symptoms should be included in stroke awareness campaigns. Further, we suggest increased competence and standardized evidence-based clinical pathways for VIs to advance all stroke health services including rehabilitation in order to improve outcomes and adaptation to future life for stroke survivors with VIs.

Should posterior cerebral artery occlusions be recanalized? Insights from the Trevo Registry

BACKGROUND AND PURPOSE

The purpose of this study was to evaluate the safety and effectiveness of mechanical thrombectomy (MT) in patients with acute ischaemic stroke related to isolated and primary posterior cerebral artery (PCA) occlusions amongst the patients enrolled in the multicentre post-market Trevo Registry.

METHOD

Amongst the 2008 patients enrolled in the Trevo Registry with acute ischaemic stroke due to large vessel occlusion treated by MT, 22 patients (1.1%) [10 females (45.5%), mean age 66.2 ± 14.3 years (range 28-91)] had a PCA occlusion [17 P1 (77.3%) and five P2 occlusions (22.7%)]. Recanalization after the first Trevo (Stryker, Fremont, CA, USA) pass and at the end of the procedure was rated using the modified Thrombolysis in Cerebral Infarction (mTICI) score. Procedure-related complications (i.e. groin puncture complication, perforation, symptomatic haemorrhage, embolus in a new territory) were also recorded. The modified Rankin Scale at 90 days was assessed.

RESULTS

Median National Institutes of Health Stroke Scale at admission was 14 (interquartile range 8-16). Stroke aetiology was cardio-embolic in 68.2% of cases. Half of the patients (11/22) received intravenous tissue plasminogen activator. 54.5% of the patients were treated under general anaesthesia. Reperfusion (i.e. mTICI 2b or 3) after first pass was obtained in 65% of cases. Final mTICI 2b-3 reperfusion was obtained in all cases. Only one (4.5%) procedure-related complication was recorded (puncture site) that resolved after surgery. At 90-day follow-up, modified Rankin Scale 0-2 was obtained in 59% of the patients and 9.1% died within the first 3 months after MT.

CONCLUSION

Mechanical thrombectomy for PCA occlusions seems to be safe (<5% procedure-related complications) and effective. Larger repository datasets are needed.

Prehospital pathways of occipital stroke patients with mainly visual symptoms

OBJECTIVES

Occipital ischemic strokes typically cause homonymous visual field defects, for which means of rehabilitation are limited. Intravenous thrombolysis is increasingly and successfully used for their acute treatment. However, recognition of strokes presenting with mainly visual field defects is challenging for both patients and healthcare professionals. We studied prehospital pathways of occipital stroke patients with mainly visual symptoms to define obstacles in their early recognition.

MATERIALS & METHODS

This observational, retrospective, registry-based study comprises occipital stroke patients with isolated visual symptoms treated at the neurological emergency department of Helsinki University Central Hospital in 2010-2015. We analyzed their prehospital pathways, including time from symptom onset to admission at the neurological emergency department (ODT), the number of points of care, the percentage of patients with ODT≤4.5 hours, and factors associated with delay.

RESULTS

Among 245 patients, only 20.8% arrived within 4.5 hours and 6.5% received IV thrombolysis. Delayed arrival was most often due to patients' late contact to health care. Of the patients, 27.3% arrived through at least two points of care, and differential diagnostics to ophthalmologic disorders proved particularly challenging. ODT≤4.5 hours was associated with EMS utilization, direct arrival, and atrial fibrillation; a visit at an ophthalmologist and initial misdiagnosis were associated with ODT>4.5 hours. After multivariable analysis, only direct arrival predicted ODT≤4.5 hours.

CONCLUSIONS

Occipital stroke patients with visual symptoms contact health care late, are inadequately recognized, and present with complex prehospital pathways. Consequently, they are often ineligible for IV thrombolysis. This presents a missed opportunity for preventing permanent visual field defects.

[Stroke due to acute occlusion of the basilar artery : Diagnosis and treatment]

Acute occlusion of the basilar artery is a rare and, if left untreated, severe neurovascular condition with a high mortality. The clinical presentation is often atypical and hence diagnosis may be delayed. Because of the devastating natural course, recanalization strategies were often more aggressive than in patients with occlusions in the anterior circulation. To date, there is no evidence-based therapy, and recent larger registry studies and meta-analyses do not show a clear superiority of endovascular approaches over systemic thrombolysis alone. The current review aims to provide an overview of the most critical aspects in clinical and radiological diagnosis and treatment of basilar artery thrombosis.