Point-of-Care Ultrasound to Detect Acute Large Vessel Occlusions in Stroke Patients: A Proof-of-Concept Study.

BACKGROUND AND PURPOSE: A primary admission of patients with suspected acute ischemic stroke and large vessel occlusion (LVO) to centers capable of providing endovascular stroke therapy (EVT) may induce shorter time to treatment and better functional outcomes. One of the limitations in this strategy is the need for accurately identifying LVO patients in the prehospital setting. We aimed to study the feasibility and diagnostic performance of point-of-care ultrasound (POCUS) for the detection of LVO in patients with acute stroke. METHODS: We conducted a proof-of-concept study and selected 15 acute ischemic stroke patients with angiographically confirmed LVO and 15 patients without LVO. Duplex ultrasonography (DUS) of the common carotid arteries was performed, and flow profiles compatible with LVO were scored independently by one experienced and one junior neurologist. RESULTS: Among the 15 patients with LVO, 6 patients presented with an occlusion of the carotid-T and 9 patients presented with an M1 occlusion. Interobserver agreement between the junior and the experienced neurologist was excellent (kappa = 0.813, p < 0.001). Flow profiles of the CAA allowed the detection of LVO with a sensitivity of 73%, a positive predictive value of 92 and 100%, and a c-statistics of 0.83 (95%CI = 0.65-0.94) and 0.87 (95%CI = 0.69-0.94) (experienced neurologist and junior neurologist, respectively). In comparison with clinical stroke scales, DUS was associated with better trade-off between sensitivity and specificity. CONCLUSION: POCUS in acute stroke setting is feasible, it may serve as a complementary tool for the detection of LVO and is potentially applicable in the prehospital phase.

Classification of patients with embolic stroke of undetermined source into cardioembolic and non-cardioembolic profile subgroups.

BACKGROUND AND PURPOSE: It is currently thought that embolic stroke of undetermined source (ESUS) has diverse underlying hidden etiologies, of which cardioembolism is one of the most important. The subgroup of patients with this etiology could theoretically benefit from oral anticoagulation, but it remains unclear if these patients can be correctly identified from other ESUS subgroups and which markers should be used. We aimed to determine whether a machine-learning (ML) model could discriminate between ESUS patients with cardioembolic and those with non-cardioembolic profiles using baseline demographic and laboratory variables. METHODS: Based on a prospective registry of consecutive ischemic stroke patients submitted to acute revascularization therapies, an ML model was trained using the age, sex and 11 selected baseline laboratory parameters of patients with known stroke etiology, with the aim of correctly identifying patients with cardioembolic and non-cardioembolic etiologies. The resulting model was used to classify ESUS patients into those with cardioembolic and those with non-cardioembolic profiles. RESULTS: The ML model was able to distinguish patients with known stroke etiology into cardioembolic or non-cardioembolic profile groups with excellent accuracy (area under the curve = 0.82). When applied to ESUS patients, the model classified 40.3% as having cardioembolic profiles. ESUS patients with cardioembolic profiles were older, more frequently female, more frequently had hypertension, less frequently were active smokers, had higher CHA2 DS2 -VASc (Congestive heart failure or left ventricular systolic dysfunction, Hypertension, Age ≥ 75 [doubled], Diabetes, Stroke/transient ischemic attack [doubled], Vascular disease, Age 65-74, and Sex category) scores, and had more premature atrial complexes per hour. CONCLUSIONS: An ML model based on baseline demographic and laboratory variables was able to classify ESUS patients into cardioembolic or non-cardioembolic profile groups and predicted that 40% of the ESUS patients had a cardioembolic profile.

StrokeWatch: An Instrument for Objective Standardized Real-Time Measurement of Door-to-Needle Times in Acute Ischemic Stroke Treatment.

OBJECTIVES: Monitoring critical time intervals in acute ischemic stroke treatment delivers metrics for quality of performance - the door-to-needle time being well-established. To resolve the conflict of self-reporting bias a "StrokeWatch" was designed - an instrument for objective standardized real-time measurement of procedural times. MATERIALS AND METHODS: An observational, monocentric analysis of patients receiving intravenous thrombolysis for acute ischemic stroke between January 2018 and September 2019 was performed based on an ongoing investigator-initiated, prospective, and blinded endpoint registry. Patient data and treatment intervals before and after introduction of "StrokeWatch" were compared. RESULTS: "StrokeWatch" was designed as a mobile board equipped with three digital stopwatches tracking door-to-needle, door-to-groin, and door-to-recanalization intervals as well as a form for standardized documentation. 118 patients before introduction of "StrokeWatch" (subgroup A) and 53 patients after introduction of "StrokeWatch" (subgroup B) were compared. There were no significant differences in baseline characteristics, procedural times, or clinical outcome. A non-significant increase in patients with door-to-needle intervals of 60 min or faster (93.2 vs 98.1%, p = 0.243) and good functional outcome (mRS d90 ≤ 2, 47.5 vs 58.5%, p = 0.218) as well as a significant increase in reports of delayed arrival of intra-hospital patient transport service (0.8 vs 13.2%, p = 0.001) were observed in subgroup B. CONCLUSIONS: The implementation of StrokeWatch for objective standardized real-time measurement of door-to-needle times is feasible in a real-life setting without negative impact on procedural times or outcome. It helped to reassure a high-quality treatment standard and reveal factors associated with procedural delays.

Gaze Deviation and Paresis Score (GPS) Sufficiently Predicts Emergent Large Vessel Occluding Strokes.

OBJECTIVES: The prognosis of patients with acute ischemic stroke (AIS) essentially depends on both prompt diagnosis and appropriate treatment. Endovascular stroke therapy (EST) proved to be highly efficient in the treatment of emergent large vessel occluding (ELVO) strokes in the anterior circulation. To achieve a timely diagnosis, a robust combination of few and simple signs to identify ELVOs in AIS patients applicable by paramedics in the prehospital triage is worthwhile. MATERIALS AND METHODS: This retrospective single-center study included 904 AIS patients (324 ELVO, 580 non-ELVO) admitted between 2010 and 2015 in a tertiary stroke center. We re-evaluated two symptoms based on NIHSS items, gaze deviation and hemiparesis of the limbs ("Gaze deviation and Paresis Score, GPS") for the pre-hospital prediction of ELVO. RESULTS: A positive GPS AIS in patients predicted ELVO with a sensitivity of 0.89, specificity = 0.97, positive predictive value (PPV) = 0.95, negative predictive value (NPV) = 0.94 and diagnostic odds ratio (DOR) = 34.25 (CI: 20.75-56.53). The positive Likelihood-ratio (LR+) was 29.67, the negative Likelihood ratio (LR-) 0.11. NIHSS of patients with positive GPS (gaze palsy NIHSS ≥ 0, Motor arm NIHSS ≥2 and Motor leg NIHSS ≥2) was markedly higher compared to negative GPS patients (p < 0.001). CONCLUSIONS: The GPS proved to be similarly accurate in detecting ELVO in the anterior circulation of AIS patients and even more specific than other published clinical scores. Its simplicity and clarity might enable non-neurological medical staff to identify ELVO AIS patients with high certainty in a preclinical setting.

Improvement of Endovascular Stroke Treatment: A 24-Hour Neuroradiological On-Site Service Is Not Enough.

BACKGROUND AND PURPOSE: With the advent of endovascular stroke treatment (EST) with mechanical thrombectomy, stroke treatment has also become more challenging. Purpose of this study was to investigate whether a fulltime neuroradiological on-site service and workflow optimization with a structured documentation of the interdisciplinary stroke workflow resulted in improved procedural times. MATERIAL AND METHODS: Procedural times of 322 consecutive patients, who received EST (1) before (n = 96) and (2) after (n = 126) establishing a 24-hour neuroradiological on-site service as well as (3) after implementation of a structured interdisciplinary workflow documentation ("Stroke Check") (n = 100), were analysed. RESULTS: A fulltime neuroradiological on-site service resulted in a nonsignificant improvement of procedural times during out-of-hours admissions (p ≥ 0.204). Working hours and out-of-hours procedural times improved significantly, if additional workflow optimization was realized (p ≤ 0.026). CONCLUSIONS: A 24-hour interventional on-site service is a major prerequisite to adequately provide modern reperfusion therapies in patients with acute ischemic stroke. However, simple measures like standardized and focused documentation that affect the entire interdisciplinary pre- and intrahospital stroke rescue chain seem to be important.

Relevance of standard intravenous thrombolysis in endovascular stroke therapy of a tertiary stroke center.

The majority of patients undergoing endovascular stroke treatment (EST) in randomized controlled trials received additional systemic thrombolysis ("combination or bridging therapy (C/BT)"). Nevertheless, its usefulness in this subtype of acute ischemic stroke (AIS) is discussed controversially. Of all consecutive AIS patients, who received any kind of reperfusion therapy in a tertiary university stroke center between January 2015 and March 2016, those with large vessel occlusions (LVO) and EST with or without additional C/BT, were compared primarily regarding procedural aspects. Data were extracted from an investigator-initiated, single-center, prospective and blinded end-point study. 70 AIS patients with EST alone and 118 with C/BT were identified. Significant baseline differences existed in pre-existing cardiovascular disease (52.9% (EST alone) vs. 35.6% (C/BT), p = 0.023), use of anticoagulation (30.6% vs. 5.9%, p < 0.001), and frequency of unknown time of symptom onset (65.7% vs. 32.2%, p < 0.001), in-hospital stroke (18.6% vs. 1.7%, p < 0.001), pre-treatment ASPECT scores (7.9 vs. 8.9, p = 0.004), and frequency of occlusion in the posterior circulation (18.6% vs. 5.1%, p = 0.003). Pre-interventional procedural time intervals tended to be shorter in the C/BT group, reaching statistical significance in door-to-image time (30.3 (EST alone) vs. 22.2 min (C/BT), p < 0.001). Good clinical outcome (mRS d90) was reached more often in the C/BT group (24.5% vs. 11.8%, p = 0.064). Rates of symptomatic intracranial hemorrhages (sICH) were comparable (4.3% (EST alone) vs. 6.8% (C/BT), p = 0.481). Additional systemic thrombolysis did not delay EST. On the contrary, application of IVRTPA seemed to be a positive indicator for faster EST without increased side effects.

Transfer of stroke patients impairs eligibility for endovascular stroke treatment.

BACKGROUND: Many patients who are potentially eligible for endovascular stroke treatment (EST) receive intravenous rtPA in the closest stroke unit before being transferred to tertiary centres for EST. It has been shown that clinical outcome of transferred and EST-treated patients is comparable to that of patients with direct access to EST. We analysed clinical outcome of patients, who were transferred and eventually not treated due to clinical and/or radiological deterioration. METHODS: We retrospectively analysed our prospectively maintained stroke registry for patients who were transferred for stroke therapy. RESULTS: Four hundred twenty-two of 1208 patients (35.1%), who were admitted for acute reperfusion stroke therapy between 03/10 and 01/15 were eligible for EST. Ninety-one (7.5%) of these patients were admitted specifically for EST from remote hospitals. Favorable clinical outcome rates after 90 days (mRS≤2) were comparable between 63 transferred and 295 directly-admitted patients, who received EST (P=0.699). However, transferred patients, who were eligible for EST on initial admission, were less likely to receive EST after transfer (P<0.001): twenty-two of 91 patients (24.2%), who were transferred for EST, became ineligible during transfer due to infarct demarcation. Procedural times of treated and untreated transferred patients were comparable (P≥0.508). There was a trend towards worse clinical outcome in untreated patients, without reaching statistical significance (OR, 0.269; 95% CI, 0.55-1.324; P=0.119). CONCLUSIONS: EST should be provided directly whenever possible as one in four transferred stroke patients becomes ineligible for EST during transfer. If direct transfer is not possible, indication for EST should be re-assessed after transfer.

Weekend effect in endovascular stroke treatment: do treatment decisions, procedural times, and outcome depend on time of admission?

BACKGROUND: Epidemiologic studies identified a 'weekend effect' or 'out-of-hours effect', which implies that procedural and clinical outcomes of patients with stroke, who are admitted out-of-hours, are less favorable than for patients admitted during working-hours. OBJECTIVE: To determine (1) whether our procedural times and clinical outcome were affected by an out-of-hours effect and (2) whether the decision in favor of, or against, endovascular stroke treatment (EST) depends on the time of admission. METHODS: Between February 2010 and January 2015, 6412 consecutive patients presenting with symptoms of acute ischemic stroke were evaluated for EST eligibility according to established local protocols and generally accepted consensus criteria, and dichotomized into working-hours and out-of-hours cohorts according to admission times. Within both groups, patients given EST were identified and the rate of treatment decision, procedural times, and clinical outcome were compared and analyzed. RESULTS: Clinical and radiological features of patients admitted in working-hours and out-of-hours did not differ significantly. Procedural times and clinical outcome were not affected by an out-of-hours effect (p≥0.054). 221/240 (92.1%) out-of-hours patients and 154/166 (92.8%) working-hours patients who were eligible for EST were transferred to the angiography suite for EST (p=0.798). The rationale not to treat patients who were eligible for EST did not differ between working-hours and out-of-hours admission (p=0.756). CONCLUSIONS: It is possible to produce competitive procedural times regardless of the time of admission and to prevent a treatment decision bias when standard operating procedures are applied consistently.

Risk profile and treatment options of acute ischemic in-hospital stroke.

Despite the potential immediate access to diagnosis and care, in-hospital stroke (IHS) is associated with delay in diagnosis, lower rates of reperfusion treatment, and unfavorable outcome. Endovascular reperfusion therapy has shown promising results in recent trials for community-onset strokes (COS) and is limited by less contraindications than systemic thrombolysis. Thus, endovascular approaches may offer additional acute treatment options for IHS. We performed a retrospective, observational monocentric analysis of patients with acute ischemic stroke between January 2010 and December 2014. Out of 3506 acute ischemic strokes, 331 (9.4%) were IHS. In-hospital mortality (31.4 vs. 8.0%) and duration of stay after stroke (19.5 vs. 12.1 days) were higher in IHS than in COS. Most IHS occurred in cardiologic and cardiosurgical patients after catheterization or surgery. In 111 cases (33.5%) the time of onset could not be established as a result of sedation or delayed referral resulting in delayed symptom recognition. 52 IHS (15.7%) and 828 COS (26.0%, p < 0.001) patients received any kind of reperfusion therapy, of which 59.6% (IHS) and 12.1% (COS) comprised isolated endovascular interventions (p < 0.001). Intra-hospital delays (time to brain imaging, systemic thrombolysis, and angiography) were longer and outcome parameters (mRS d90, in-hospital mortality, length of stay) were worse in IHS, whereas rates of procedural complications and intracranial hemorrhages were similar in both groups. The overall rate of reperfusion treatment is lower in IHS compared to COS, as IHS patients are less likely to be eligible for systemic thrombolysis. Interventional stroke treatment is a safe and feasible therapeutic option for patients who are not eligible for systemic thrombolysis and should be anticipated whenever IHS is diagnosed.