Focal T2 and FLAIR hyperintensities within the infarcted area: A suitable marker for patient selection for treatment?

Background and purpose

Some authors use FLAIR imaging to select patients for stroke treatment. However, the effect of hyperintensity on FLAIR images on outcome and bleeding has been addressed in only few studies with conflicting results.

Methods

466 patients with anterior circulation strokes were included in this study. They all were examined with MRI before intravenous or endovascular treatment. Baseline data and 3 months outcome were recorded prospectively. Focal T2 and FLAIR hyperintensities within the ischemic lesion were evaluated by two raters, and the PROACT II classification was applied to assess bleeding complications on follow up imaging. Logistic regression analysis was used to determine predictors of bleeding complications and outcome and to analyze the influence of T2 or FLAIR hyperintensity on outcome.

Results

Focal hyperintensities were found in 142 of 307 (46.3%) patients with T2 weighted imaging and in 89 of 159 (56%) patients with FLAIR imaging. Hyperintensity in the basal ganglia, especially in the lentiform nucleus, on T2 weighted imaging was the only independent predictor of any bleeding after reperfusion treatment (33.8% in patients with vs. 18.2% in those without; p = 0.003) and there was a non-significant trend for more bleedings in patients with FLAIR hyperintensity within the basal ganglia (p = 0.069). However, there was no association of hyperintensity on T2 weighted or FLAIR images and symptomatic bleeding or worse outcome.

Conclusion

Our results question the assumption that T2 or FLAIR hyperintensities within the ischemic lesion should be used to exclude patients from reperfusion therapy, especially not from endovascular treatment.

Cerebrospinal fluid outflow resistance as a diagnostic marker of spontaneous cerebrospinal fluid leakage

OBJECTIVE Spinal CSF leakage causes spontaneous intracranial hypotension (SIH). The aim of this study was to characterize CSF dynamics via lumbar infusion testing in patients with and without proven spinal CSF leakage in order to explore possible discriminators for the presence of an open CSF leak. METHODS This analysis included all patients with suspected SIH who were treated at the authors' institution between January 2012 and February 2015. The gold standard for "proven" CSF leakage is considered to be extrathecal contrast accumulation after intrathecal contrast injection. To characterize CSF dynamics, the authors performed computerized lumbar infusion testing to measure lumbar pressure at baseline (opening pressure) and at plateau, as well as pulse amplitude, CSF outflow resistance (R_CSF), craniospinal elastance, and pressure-volume index. RESULTS Thirty-one patients underwent clinical imaging and lumbar infusion testing and were included in the final analysis. A comparison of the 14 patients with proven CSF leakage with the 17 patients without leakage showed a statistically significantly lower lumbar opening pressure (p < 0.001), plateau pressure (p < 0.001), and R_CSF (p < 0.001) in the group with leakage. Sensitivity, specificity, and positive and negative predictive values for an R_CSF cutoff of ≤ 5 mm Hg/(ml/min) were 0.86, 1.0, 1.0, and 0.89 (area under the curve of 0.96), respectively. The median pressure-volume index was higher (p = 0.003), and baseline (p = 0.017) and plateau (p < 0.001) pulse amplitudes were lower in patients with a proven leak. CONCLUSIONS Lumbar infusion testing captures a distinct pattern of CSF dynamics associated with spinal CSF leakage. R_CSF assessed by computerized lumbar infusion testing has an excellent diagnostic accuracy and is more accurate than evaluating the lumbar opening pressure. The authors suggest inclusion of R_CSF in the diagnostic criteria for SIH.

Repeated Intravenous Thrombolysis for Early Recurrent Stroke: Challenging the Exclusion Criterion

BACKGROUND AND PURPOSE

Intravenous thrombolysis (IVT) within 4.5 hours from symptom onset improves functional outcome in patients with acute ischemic stroke. Its use in patients with previous stroke within the preceding 3 months is contraindicated because of the assumed higher risk of intracranial hemorrhage. In addition, tissue-type plasminogen activator may itself promote neurotoxicity and blood-brain barrier disruption. However, safety and effectiveness of repeated IVT is essentially unknown in patients with early (<3 months) recurrent stroke (ERS), because they were excluded from thrombolysis trials. This article reports the largest case series of repeated IVT in ERS.

METHODS

We reviewed databases of prospectively collected patient data of 8 European stroke centers for the presence of patients with ERS, who received IVT for both the index stroke and ERS. Demographics, clinical and radiological data, bleeding complications, and functional outcome were analyzed.

RESULTS

We identified 19 subjects with repeated IVT in ERS. Mean age was 68±12 years, and 37% of them were female. Median interthrombolysis interval was 30 days (interquartile range, 13-50). Functional independence (modified Rankin scale score ≤2) was achieved in 79% of patients after the first and in 47.4% after repeated IV tissue-type plasminogen activator, respectively. There was no symptomatic intracranial hemorrhage. Median final infarct volume after the first IVT was 1.5 cm(3) (interquartile range, 0.5-3.1).

CONCLUSIONS

Patients with small infarct volumes and robust clinical improvement might be considered for repeated IVT within 3 months. Studies following strict protocols and larger registries incorporating these patients might serve to identify selection criteria for the safe use of repeated IVT in ERS.

Abstract 205: Preceding Valsalva Maneuver Significantly Associated With Pathogenic Patent Foramen Ovale (PFO) in Patients With Cryptogenic Stroke

Background: In patients with cryptogenic stroke (CS), a patent foramen ovale (PFO) can be incidental or pathogenic. The Risk of Paradoxical Embolism (RoPE) score has been developed to determine the likelihood that a PFO is pathogenic or incidental using clinical variables. We hypothesize that echocardiographic features and conditions promoting paradoxical embolism differ between patients with pathogenic and incidental PFOs.

Methods: The International PFO Consortium collects clinical, radiological and echocardiographic data of patients with CS and PFO. In the original RoPE score, a value of 0-6 was classified as a low RoPE score and 7-10 as a high score. Since information on cortical versus deep stroke location (one of the items on the RoPE score) was not available, we used two alternative approaches to stratify for PFO pathogenicity. In a first approach, we used a 9-point score and lowered the cut-off for dichotomization by 1 point (RoPE score 0-5 vs 6-9). In a second approach, patients with a RoPE score of 6 were excluded since they could either be classified as low or high RoPE score depending on stroke location. The associations between RoPE stratum and echocardiographic features (atrial septal aneurysm (ASA), right-to-left shunt (RLS) at rest and large RLS) as well as conditions promoting paradoxical embolism (deep vein thrombosis (DVT), pulmonary embolism (PE) and Valsalva maneuver (VM) were studied.

Results: We analyzed 1044 CS patients with a PFO. Average age was 55 (SD 16) and 635 patients (61%) were male. Preceding VM was more frequent in patients with a high vs low RoPE score in both analyses: 11% vs 5% (OR: 2.1 95%CI 1.3-4.3) and 10% vs 5% (OR: 2.0 95%CI 1.2-3.6). The distribution of ASA (35% vs 34% and 32% vs 34%, in the first and the second analysis respectively), RLS at rest (28% vs 28% and 29% vs 28%), large RLS (67% vs 66% and 65% vs 66%), PE (2% vs 2% and 1% vs 2%), and DVT (4% vs 4% and 3% vs 4%) did not differ by RoPE stratum.

Conclusion: In patients with CS, preceding VM was significantly associated with pathogenic PFO, while echocardiographic features or conditions promoting paradoxical embolism were not. The formation of a significant right-to-left pressure gradient at the atrial septum level appears to play a substantial role in the pathogenicity of PFO.

Abstract WP228: Stratification of Patent Foramen Ovale (PFO) Pathogenicity Using the RoPE Score Differs in Women and Men

Background: A patent foramen ovale (PFO) discovered in patients with cryptogenic stroke (CS) may be incidental or pathogenic. Recently, a Risk of Paradoxical Embolism (RoPE) score has been proposed to stratify patients by their PFO pathogenicity. Based on this score, the probability that a PFO is incidental (rather than pathogenic) increases with advancing age, deep stroke location, or the presence of cardiovascular risk factors (RF). Given that RF accumulate at a later age in women than in men, we hypothesize that there are gender differences in the variables used for RoPE score calculation.

Methods: The distribution of RF (history of hypertension, diabetes or stroke/TIA, current smoking, and age categories as defined in the original RoPE score publication) was compared by sex in the entire cohort of 1044 CS patients as well as within the groups with low (0-5) and high (7-10) RoPE scores (due to lacking information on cortical versus deep stroke location, we excluded all patients with a RoPE score of 6, since they could be either classified with low or high RoPE score depending on stroke location). Furthermore, for each patient we calculated the age impact ratio (AIR): the points assigned for the corresponding age category divided by the RoPE score. Gender comparisons of AIR were drawn in the entire cohort and within the RoPE score strata.

Results: Average age was 55.5 years and 635 patients (61%) were male. In the entire cohort, the distribution of age categories and RF as well as AIR did not differ between men and women. In the higher RoPE stratum (PFO likely pathogenic), women were younger than men (median, 38 years vs 45 years, P=0.036). The distribution of RF and the AIR did not differ between sexes. In the lower PFO stratum (PFO likely incidental), men were younger than women (median, 62 years vs 66 years, P=0.011). The AIR was lower in women than in men (mean, 0.24 vs 0.29, P=0.013). There were no gender differences in the distribution of RF.

Conclusions: There are significant gender differences in age among patients with CS and PFO, with women being younger than men in the higher RoPE stratum and vice versa in the lower RoPE stratum. More women than men are classified as having an incidental PFO because of their advancing age rather than the accumulation of RF.

Occlusion Location of Middle Cerebral Artery Stroke and Outcome after Endovascular Treatment

BACKGROUND

The aim of this study was to analyze the influence of the location of middle cerebral artery (MCA) occlusion on recanalization, complications and outcome after endovascular therapy.

METHODS

Four-hundred sixty-four patients with acute MCA occlusions were treated with endovascular therapy.

RESULTS

Two-hundred ninety-three patients had M1 occlusions, 116 had M2, and 55 had M3/4 occlusions. Partial or complete recanalization was more frequently achieved in M1 (76.8%) than in M2 (59.1%) or M3/4 (47.3%, p < 0.001) occlusions, but favorable outcome (modified Rankin Scale 0-2) was less frequent in M1 (50.9%) than M2 (63.7%) or M3/4 (72.7%, p = 0.018) occlusions. Symptomatic intracerebral hemorrhage (ICH) did not differ between occlusion sites, but asymptomatic ICH was more common in M1 (22.6%) than in M2 occlusions (8.6%, p = 0.003). Recanalization was associated with favorable outcome in M1 (p < 0.001) and proximal M2 (p = 0.003) but not in distal M2 or M3/4 occlusions.

CONCLUSIONS

Recanalization with endovascular therapy was more frequently achieved in patients with proximal than distal MCA occlusions, but recanalization was associated with favorable outcome only in M1 and proximal M2 occlusions. Outcome was better with distal than proximal occlusions. This study shows that recanalization can be used as a surrogate marker for clinical outcome only in patients with proximal occlusions.

Younger Stroke Patients With Large Pretreatment Diffusion-Weighted Imaging Lesions May Benefit From Endovascular Treatment

BACKGROUND AND PURPOSE

Lesion volume on diffusion-weighted magnetic resonance imaging (DWI) before acute stroke therapy is a predictor of outcome. Therefore, patients with large volumes are often excluded from therapy. The aim of this study was to analyze the impact of endovascular treatment in patients with large DWI lesion volumes (>70 mL).

METHODS

Three hundred seventy-two patients with middle cerebral or internal carotid artery occlusions examined with magnetic resonance imaging before treatment since 2004 were included. Baseline data and 3 months outcome were recorded prospectively. DWI lesion volumes were measured semiautomatically.

RESULTS

One hundred five patients had lesions >70 mL. Overall, the volume of DWI lesions was an independent predictor of unfavorable outcome, survival, and symptomatic intracerebral hemorrhage (P<0.001 each). In patients with DWI lesions >70 mL, 11 of 31 (35.5%) reached favorable outcome (modified Rankin scale score, 0-2) after thrombolysis in cerebral infarction 2b-3 reperfusion in contrast to 3 of 35 (8.6%) after thrombolysis in cerebral infarction 0-2a reperfusion (P=0.014). Reperfusion success, patient age, and DWI lesion volume were independent predictors of outcome in patients with DWI lesions >70 mL. Thirteen of 66 (19.7%) patients with lesions >70 mL had symptomatic intracerebral hemorrhage with a trend for reduced risk with avoidance of thrombolytic agents.

CONCLUSIONS

There was a growing risk for poor outcome and symptomatic intracerebral hemorrhage with increasing pretreatment DWI lesion volumes. Nevertheless, favorable outcome was achieved in every third patient with DWI lesions >70 mL after successful endovascular reperfusion, whereas after poor or failed reperfusion, outcome was favorable in only every 12th patient. Therefore, endovascular treatment might be considered in patients with large DWI lesions, especially in younger patients.

In-vivo phase contrast magnetic resonance angiography of the cerebrovascular system: a comparative study with duplex sonography

PURPOSE

Assessment of the cerebral blood flow (CBF) is crucial in the evaluation of patients with steno-occlusive diseases of the arteries supplying the brain for prediction of stroke risk. Quantitative phase contrast magnetic resonance angiography (PC-MRA) can be utilised for noninvasive quantification of CBF. The aim of this study was to validate in-vivo PC-MRA data by comparing them with colour-coded duplex (CCD) sonography in patients with cerebrovascular disease.

METHODS AND MATERIALS

We examined 24 consecutive patients (mean age 63 years) with stenosis of arteries supplying the brain using PC-MRA and CCD. Velocities were measured in a total of 209 stenotic and healthy arterial segments (110 extra- and 99 intracranial).

RESULTS

Moderate to good correlation of velocity measurements between both techniques was observed in all six extracranial and five out of seven intracranial segments (p <0.05). Velocities measured with CCD sonography were generally higher than those obtained by PC-MRA. Reversal of flow direction was detected consistently with both methods.

CONCLUSION

PC-MRA represents a robust, standardised magnetic resonance imaging technique for blood flow measurements within a reasonable acquisition time, potentially evolving as valuable work-up tool for more precise patient stratification for revascularisation therapy. PC-MRA overcomes relevant weaknesses of CCD in being not operator-dependent and not relying on a bone window to assess the intracranial arteries.

Outcome of patients with occlusions of the internal carotid artery or the main stem of the middle cerebral artery with NIHSS score of less than 5: comparison between thrombolysed and non-thrombolysed patients

BACKGROUND AND PURPOSE

The use of thrombolysis in patients with minor neurological deficits and large vessel occlusion is controversial.

METHODS

We compared the outcome of patients with low National Institutes of Health Stroke Scale (NIHSS) scores and large vessel occlusions between thrombolysed and non-thrombolysed patients.

RESULTS

88 (1.7%) of 5312 consecutive patients with acute (within 24 h) ischaemic stroke had occlusions of the internal carotid or the main stem of the middle cerebral artery and baseline NIHSS scores ≤5.47 (53.4%) were treated without thrombolysis, and 41 (46.6%) received intravenous thrombolysis, endovascular therapy or both. Successful recanalisation on MR or CT angiography at 24 h was more often observed in thrombolysed than in non-thrombolysed patients (78.9% versus 10.5%; p<0.001). Neurological deterioration (increase of NIHSS score ≥1 compared to baseline) was observed in 22.7% of non-thrombolysed versus 10.3% of thrombolysed after 24 h (p=0.002), in 33.3% versus 12.5% at hospital discharge (p=0.015) and in 41.4% versus 15% at 3 months (p<0.001). Symptomatic intracerebral haemorrhage occurred in two (asymptomatic in five) thrombolysed and in none (asymptomatic in three) non-thrombolysed. Thrombolysis was an independent predictor of favourable outcome (p=0.030) but not survival (p=0.606) at 3 months.

CONCLUSIONS

Non-thrombolysed patients with mild deficits and large vessel occlusion deteriorated significantly more often within 3 months than thrombolysed patients. Symptomatic intracerebral haemorrhages occurred in less than 5% of patients in both groups. These data suggest that thrombolysis is safe and effective in these patients. Therefore, randomised trials in patients with large vessel occlusions and mild or rapidly improving symptoms are needed.

Risk factors, aetiology and outcome of ischaemic stroke in young adults: the Swiss Young Stroke Study (SYSS)

Ischaemic stroke (IS) in young adults has been increasingly recognized as a serious health condition. Stroke aetiology is different in young adults than in the older population. This study aimed to investigate aetiology and risk factors, and to search for predictors of outcome and recurrence in young IS patients. We conducted a prospective multicentre study of consecutive IS patients aged 16-55 years. Baseline demographic data, risk factors, stroke aetiology including systematic genetic screening for Fabry disease and severity were assessed and related to functional neurological outcome (modified Rankin Scale, mRS), case fatality, employment status, place of residence, and recurrent cerebrovascular events at 3 months. In 624 IS patients (60% men), median age was 46 (IQR 39-51) years and median NIHSS on admission 3 (IQR 1-8). Modifiable vascular risk factors were found in 73%. Stroke aetiology was mostly cardioembolism (32%) and of other defined origin (24%), including cervicocerebral artery dissection (17%). Fabry disease was diagnosed in 2 patients (0.3%). Aetiology remained unknown in 20%. Outcome at 3 months was favourable (mRS 0-1) in 61% and fatal in 2.9%. Stroke severity (p < 0.001) and diabetes mellitus (p = 0.023) predicted unfavourable outcome. Stroke recurrence rate at 3 months was 2.7%. Previous stroke or TIA predicted recurrent cerebrovascular events (p = 0.012). In conclusion, most young adults with IS had modifiable vascular risk factors, emphasizing the importance of prevention strategies. Outcome was unfavourable in more than a third of patients and was associated with initial stroke severity and diabetes mellitus. Previous cerebrovascular events predicted recurrent ones.

Abstract 208: Vascular Risk Factors But Not Transesophageal Echocardiography (TEE) Features Are Associated With Stroke Recurrence in Patients With Cryptogenic Stroke (CS) and Patent Foramen Ovale (PFO)

Background and purpose: Recurrent ischemic stroke in patients with CS and PFO has been proposed as a marker of increased risk for paradoxical embolism. It is unclear, whether the excess risk is driven by specific features of the PFO (right-to-left shunt (RLS) size, RLS at rest, associated atrial septum aneurysm (ASA)) or the presence of vascular risk factors (vRF). We compare the prevalence of vRF, TEE features, and baseline medications in PFO patients with first-ever versus multiple CS.

Methods: From September 2008 to March 2013, the International PFO Consortium enrolled 993 patients with ischemic stroke or transient ischemic attack (TIA) and newly diagnosed PFO. In this analysis of baseline data, we included 386 patients with first-ever CS and no radiological evidence of prior cerebral ischemia (first-ever CS group, mean age, 52y) as well as 71 patients with recurrent CS and multiple ischemic lesions on CT and/or MRI (multiple CS group, mean age, 59y). Patients with TIA as index event, those with first-ever CS but additional “silent” ischemic lesions on imaging as well as those with recurrent CS without radiological findings of prior cerebral ischemia were excluded. We used nonparametric tests for independent samples and the Bonferroni correction for multiple comparisons.

Results: Age > 55y (63% vs. 44%, P=0.001), hypertension (52% vs. 30%, P=0.001), hyperlipidemia (64% vs. 44%, P=0.003), and coronary artery disease (15% vs. 3%, P=0.001) were significantly more frequent in the multiple CS than in the first-ever CS group. The frequencies of male gender, current smoking, diabetes, migraine with or without aura, associated ASA, RLS size, and RLS at rest did not differ between groups. At baseline, patients with multiple CS were more likely to be on antiplatelets (50% vs. 18%), antihypertensive (51% vs. 22%) or lipid lowering drugs (44% vs. 10%, P=0.001 for each comparison) than patients with first-ever CS. The frequency of anticoagulant treatment did not differ between groups.

Conclusions: In patients with CS, vRF but not specific PFO features were associated with recurrent cerebral ischemic events. The ongoing prospective part of the International PFO Consortium will likely shed light upon the role of vRF control for secondary stroke prevention in patients with PFO.

Determinants of antithrombotic choice for patent foramen ovale in cryptogenic stroke

OBJECTIVE

We examined the influence of clinical, radiologic, and echocardiographic characteristics on antithrombotic choice in patients with cryptogenic stroke (CS) and patent foramen ovale (PFO), hypothesizing that features suggestive of paradoxical embolism might lead to greater use of anticoagulation.

METHODS

The Risk of Paradoxical Embolism Study combined 12 databases to create the largest dataset of patients with CS and known PFO status. We used generalized linear mixed models with a random effect of component study to explore whether anticoagulation was preferentially selected based on the following: (1) younger age and absence of vascular risk factors, (2) "high-risk" echocardiographic features, and (3) neuroradiologic findings.

RESULTS

A total of 1,132 patients with CS and PFO treated with anticoagulation or antiplatelets were included. Overall, 438 participants (39%) were treated with anticoagulation with a range (by database) of 22% to 54%. Treatment choice was not influenced by age or vascular risk factors. However, neuroradiologic findings (superficial or multiple infarcts) and high-risk echocardiographic features (large shunts, shunt at rest, and septal hypermobility) were predictors of anticoagulation use.

CONCLUSION

Both antithrombotic regimens are widely used for secondary stroke prevention in patients with CS and PFO. Radiologic and echocardiographic features were strongly associated with treatment choice, whereas conventional vascular risk factors were not. Prior observational studies are likely to be biased by confounding by indication.

Recurrent stroke predictors differ in medically treated patients with pathogenic vs. other PFOs

OBJECTIVE

To examine predictors of stroke recurrence in patients with a high vs a low likelihood of having an incidental patent foramen ovale (PFO) as defined by the Risk of Paradoxical Embolism (RoPE) score.

METHODS

Patients in the RoPE database with cryptogenic stroke (CS) and PFO were classified as having a probable PFO-related stroke (RoPE score of >6, n = 647) and others (RoPE score of ≤6 points, n = 677). We tested 15 clinical, 5 radiologic, and 3 echocardiographic variables for associations with stroke recurrence using Cox survival models with component database as a stratification factor. An interaction with RoPE score was checked for the variables that were significant.

RESULTS

Follow-up was available for 92%, 79%, and 57% at 1, 2, and 3 years. Overall, a higher recurrence risk was associated with an index TIA. For all other predictors, effects were significantly different in the 2 RoPE score categories. For the low RoPE score group, but not the high RoPE score group, older age and antiplatelet (vs warfarin) treatment predicted recurrence. Conversely, echocardiographic features (septal hypermobility and a small shunt) and a prior (clinical) stroke/TIA were significant predictors in the high but not low RoPE score group.

CONCLUSION

Predictors of recurrence differ when PFO relatedness is classified by the RoPE score, suggesting that patients with CS and PFO form a heterogeneous group with different stroke mechanisms. Echocardiographic features were only associated with recurrence in the high RoPE score group.

Age dependency of safety and outcome of endovascular therapy for acute stroke

Elderly patients generally experience less favorable outcomes and higher mortality after acute stroke than younger patients. The aim of this study was to analyze the influence of age on outcome and safety after endovascular therapy in a large cohort of patients aged between 20 and 90 years. We prospectively acquired data of 1,000 stroke patients treated with endovascular therapy at a single center. Logistic regression analysis was performed to determine predictors of outcome and linear regression analysis to evaluate the association of age and outcome after 3 months. Younger age was an independent predictor of favorable outcome (OR 0.954, p < 0.001) and survival (OR 0.947, p < 0.001) in multivariate regression analysis. There was a linear relationship between age and outcome. Ever increase in 26 years of age was associated with an increase in the modified Rankin Scale of 1 point (p < 0.001). However, increasing age was not a risk factor for symptomatic (p = 0.086) or asymptomatic (p = 0.674) intracerebral hemorrhage and did not influence recanalization success (p = 0.674). Advancing age was associated with a decline of favorable outcomes and survival after endovascular therapy. This decline was linear from age 20 to 90 years, but was not related to lower recanalization rates or higher bleeding risk in the elderly. The efficacy of endovascular stroke therapy seems to be preserved also in the elderly and other factors than efficacy of endovascular therapy such as decreased plasticity are likely to explain the worse outcome with advancing age.

Risk of very early recurrent cerebrovascular events in symptomatic carotid artery stenosis

Object

The risk of recurrence of cerebrovascular events within the first 72 hours of admission in patients hospitalized with symptomatic carotid artery (CA) stenoses and the risks and benefits of emergency CA intervention within the first hours after the onset of symptoms are not well known. Therefore, the authors aimed to assess 1) the ipsilateral recurrence rate within 72 hours of admission, in the period from 72 hours to 7 days, and after 7 days in patients presenting with nondisabling stroke, transient ischemic attack (TIA), or amaurosis fugax (AF), and with an ipsilateral symptomatic CA stenosis of 50% or more, and 2) the risk of stroke in CA interventions within 48 hours of admission versus the risk in interventions performed after 48 hours.

Methods

Ninety-four patients were included in this study. These patients were admitted to hospital within 48 hours of a nondisabling stroke, TIA, or AF resulting from a symptomatic CA stenosis of 50% or more. The patients underwent carotid endarterectomy (85 patients) or CA stenting (9 patients). At baseline, the cardiovascular risk factors of the patients, the degree of symptomatic CA stenosis, and the type of secondary preventive treatment were assessed. The in-hospital recurrence rate of stroke, TIA, or AF ipsilateral to the symptomatic CA stenosis was determined for the first 72 hours after admission, from 72 hours to 7 days, and after 7 days. Procedure-related cerebrovascular events were also recorded.

Results

The median time from symptom onset to CA intervention was 5 days (interquartile range 3.00–9.25 days). Twenty-one patients (22.3%) underwent CA intervention within 48 hours after being admitted. Overall, 15 recurrent cerebrovascular events were observed in 12 patients (12.8%) in the period between admission and CA intervention: 3 strokes (2 strokes in progress and 1 stroke) (3.2%), 5 TIAs (5.3%), and 1 AF (1.1%) occurred within the first 72 hours (total 9.6%) of admission; 1 TIA (1.1%) occurred between 72 hours and 7 days, and 5 TIAs (5.3%) occurred after more than 7 days. The corresponding actuarial cerebrovascular recurrence rates were 11.4% (within 72 hours of admission), 2.4% (between 72 hours and 7 days), and 7.9% (after 7 days). Among baseline characteristics, no predictive factors for cerebrovascular recurrence were identified.

Procedure-related cerebrovascular events occurred at a rate of 4.3% (3 strokes and 1 TIA), and procedures performed within the first 48 hours and procedures performed after 48 hours had a similar frequency of these events (4.5% vs 4.1%, respectively; p = 0.896).

Conclusions

The in-hospital recurrence of cerebrovascular events was quite low, but all recurrent strokes occurred within 72 hours. The risk of stroke associated with a CA intervention performed within the first 48 hours was not increased compared with that for later interventions. This raises the question of the optimal timing of CA intervention in symptomatic CA stenosis. To answer this question, more data are needed, preferably from large randomized trials.

Outcome of standard and high-risk patients with acute anterior circulation stroke after stent retriever thrombectomy

BACKGROUND AND PURPOSE

Stent retrievers have become an important tool for the treatment of acute ischemic stroke. The aim of this study was to analyze outcome and complications in a large cohort of patients with stroke treated with the Solitaire stent retriever. The study also included patients who did not meet standard inclusion criteria for endovascular treatment: low or high baseline National Institutes of Health Stroke Scale score, ≥80 years of age, extensive ischemic signs in middle cerebral artery territory, and time from symptom onset to endovascular intervention>8 hours.

METHODS

Consecutive patients with acute anterior circulation stroke treated with the Solitaire FR were analyzed. Data on characteristics of endovascular interventions, complications, and clinical outcome were collected prospectively. Patients who met standard inclusion criteria were compared with those who did not.

RESULTS

A total of 227 patients were included. Mean age was 68.2±14.7 years, and median National Institutes of Health Stroke Scale score on admission was 16 (range, 2-36). Reperfusion was successful (thrombolysis in cerebral infarction, 2b-3) in 70.9%. Outcome was favorable (modified Rankin Scale, 0-2) in 57.7% of patients who met standard inclusion criteria and 30.3% of those who did not. The rates for symptomatic intracranial hemorrhage were 3.7% and 13.1%, for death 11.4% and 33.8%, and for symptomatic intraprocedural complications 2.5% and 4.8%, respectively.

CONCLUSIONS

Patients<80 years of age, without extensive pretreatment ischemic signs, and baseline National Institutes of Health Stroke Scale score≤30 had high rates of favorable outcome and low periprocedural complication rates after Solitaire thrombectomy. Successful reperfusion was also common in patients not fulfilling standard inclusion criteria, but worse clinical outcomes warrant further research with a special focus on optimal patient selection.

National Institutes of Health stroke scale score and vessel occlusion in 2152 patients with acute ischemic stroke

BACKGROUND AND PURPOSE

There is some controversy on the association of the National Institutes of Health Stroke Scale (NIHSS) score to predict arterial occlusion on MR arteriography and CT arteriography in acute stroke.

METHODS

We analyzed NIHSS scores and arteriographic findings in 2152 patients (35.4% women, mean age 66 ± 14 years) with acute anterior or posterior circulation strokes.

RESULTS

The study included 1603 patients examined with MR arteriography and 549 with CT arteriography. Of those, 1043 patients (48.5%; median NIHSS score 5, median time to clinical assessment 179 minutes) showed an occlusion, 887 in the anterior (median NIHSS score 7/0-31), and 156 in the posterior circulation (median NIHSS score 3/0-32). Eight hundred sixty visualized occlusions (82.5%) were located centrally (ie, in the basilar, intracranial vertebral, internal carotid artery, or M1/M2 segment of the middle cerebral artery). NIHSS scores turned out to be predictive for any vessel occlusions in the anterior circulation. Best cut-off values within 3 hours after symptom onset were NIHSS scores ≥ 9 (positive predictive value 86.4%) and NIHSS scores ≥ 7 within >3 to 6 hours (positive predictive value 84.4%). Patients with central occlusions presenting within 3 hours had NIHSS scores <4 in only 5%. In the posterior circulation and in patients presenting after 6 hours, the predictive value of the NIHSS score for vessel occlusion was poor.

CONCLUSIONS

There is a significant association of NIHSS scores and vessel occlusions in patients with anterior circulation strokes. This association is best within the first hours after symptom onset. Thereafter and in the posterior circulation the association is poor.

Abstract 198: PFO and Recurrent Stroke: Predictors Differ In Patients With “Probable Pathogenic” Versus Other PFOs

Background The “RoPE Score” is a predictive model created to stratify patients by the likelihood that a patent foramen ovale (PFO) is incidental or pathogenic using clinical variables. We hypothesized that the predictors of recurrent stroke differ between patients with pathogenic and incidental PFOs.

Methods Patients in the Risk of Paradoxical Embolism (RoPE) database with cryptogenic stroke (CS) and PFO were classified as having a probable pathogenic PFO (RoPE Score of >6, estimated PFO attributable fraction 72-99%, n=646) and others (RoPE Score of <6 points estimated PFO attributable fraction 0-72%, n=678). We tested 15 clinical, 5 radiological, and 3 echo variables for associations with stroke recurrence using Cox survival models with component database as a stratification factor. An interaction with RoPE score was checked for the variables that were significant.

Results Follow-up was available for 91%, 80%, and 58% at 1, 2, and 3 years. Overall, a higher recurrence risk was associated with an index TIA, not being on a statin at baseline, and having a prior radiological stroke. For the low RoPE score group, older age, male sex, high cholesterol and antiplatelet (vs warfarin) treatment predicted recurrence. For those with high RoPE scores, predictors were prior (clinical) stroke/TIA and 2 echo features: septal hypermobility and a small shunt (<10 bubbles).

Conclusions Predictors of recurrence differ when PFO relatedness is classified by the RoPE Score. The hypothesis that patients with CS and PFO form a heterogenous group with different stroke mechanisms is supported. Conventional stroke risk factors were strong predictors among patients with lower RoPE scores. Echocardiographic features - including a counterintuitive association between smaller shunts and increased recurrence risk - were uniquely predictive in the high RoPE score group (likely pathogenic PFO).

Abstract WP185: Cryptogenic Stroke and Patent Foramen Ovale: Posterior Circulation Strokes Are More Common In Men Than In Women

Background Stroke databanks have consistently found a high ratio of anterior circulation (AC) to posterior circulation (PC) strokes without significant differences when compared for vascular risk factors, stroke etiology, treatments and outcome. One study suggested that there was a deviation from this consistent observation when comparing men and women with cryptogenic stroke (CS) and patent foramen ovale (PFO). We tested these associations using the RoPE database.

Methods The Risk of Paradoxical Embolism (RoPE) Study is an international collaboration of 12 merged cohort studies of patients with CS and known PFO status (n=3674). This analysis was restricted to those subjects in the RoPE database with index strokes in the AC or PC (excluding both or unknown) from the 7 databases that had data for CS with, and without, PFO. We compared the effect of sex on infarct location among patients with versus without PFO. We used generalized linear mixed models to examine whether PFO status modified the gender effect on infarct location adjusting for study cohort as a random effect.

Results Among cryptogenic stroke patients both with and without PFO, AC strokes were more common (61%) than PC overall (n=1535). Among patients with PFO, PC stroke was higher in men than in women (50% vs. 33%, OR 2.23, 95% CI: 1.58-3.13). This gender effect was attenuated in those without PFO (38% vs. 31%; OR 1.32, 95% CI: 0.98-1.77). The gender-by-PFO-status interaction was significant (p= 0.0224) and was highly consistent across study cohorts.

Conclusions These data confirm that males with CS and PFO contravene the otherwise consistent pattern that AC strokes are more commonly observed than PC strokes in stroke populations. The potential mechanisms underlying this interaction between gender and PFO-status remain to be elucidated.

Neuroimaging findings in cryptogenic stroke patients with and without patent foramen ovale

BACKGROUND AND PURPOSE

Patent foramen ovale (PFO) and cryptogenic stroke are commonly associated but some PFOs are incidental. Specific radiological findings associated with PFO may be more likely to indicate a PFO-related cause. We examined whether specific radiological findings are associated with PFO among subjects with cryptogenic stroke and known PFO status.

METHODS

We analyzed the Risk of Paradoxical Embolism(RoPE) Study database of subjects with cryptogenic stroke and known PFO status, for associations between PFO and: (1) index stroke seen on imaging, (2) index stroke size, (3) index stroke location, (4) multiple index strokes, and (5) prior stroke on baseline imaging. We also compared imaging with purported high-risk echocardiographic features.

RESULTS

Subjects (N=2680) were significantly more likely to have a PFO if their index stroke was large (odds ratio [OR], 1.36; P=0.0025), seen on index imaging (OR, 1.53; P=0.003), and superficially located (OR, 1.54; P<0.0001). A prior stroke on baseline imaging was associated with not having a PFO (OR, 0.66; P<0.0001). Finding multiple index strokes was unrelated to PFO status (OR, 1.21; P=0.161). No echocardiographic variables were related to PFO status.

CONCLUSIONS

This is the largest study to report the radiological characteristics of patients with cryptogenic stroke and known PFO status. Strokes that were large, radiologically apparent, superficially located, or unassociated with prior radiological infarcts were more likely to be PFO-associated than were unapparent, smaller, or deep strokes, and those accompanied by chronic infarcts. There was no association between PFO and multiple acute strokes nor between specific echocardiographic PFO features with neuroimaging findings.

Plaque characteristics of asymptomatic carotid stenosis and risk of stroke

BACKGROUND

The optimal treatment of asymptomatic carotid stenosis (ACS) is controversial. To optimize the risk-benefit ratio of carotid artery revascularization, it is crucial to identify ACS patients who are at increased stroke risk. Recent data suggest that plaque vulnerability depends on its composition. Therefore, we assessed plaque composition in ACS to determine predictors for ipsilateral cerebrovascular events.

METHODS

62 patients with 65 ACS ≥50% underwent 3-T MRI of the carotid bifurcation (TOF, special dark-blood weighted noncontrast and contrast-enhanced T(1) and T(2) images) and of the brain. The different plaque components (lipid core, intraplaque hemorrhage, calcification and the status of the fibrous cap) were assessed. Furthermore, the plaque volume and the volume of clinically silent cortical and subcortical infarcts in the territory of the stenosed carotid artery as seen on FLAIR images were determined by using a semi-automated software. Carotid stenosis was considered asymptomatic if there had not been any clinically apparent ischemic events in the corresponding vascular territory within the previous 6 months. During follow-up, information on the occurrence of cerebrovascular events, medical treatment and sonographic changes of the stenosis was collected.

RESULTS

At baseline, 24 ACS (37%) were classified as high grade. A lipid-rich necrotic core was the dominant plaque component in 16 ACS (25%). The plaque volume was higher in ACS with a lipid-rich necrotic core as dominant plaque component (p = 0.002) and in patients with prior stroke/TIA (p = 0.010). After a median follow-up of 18.9 months (interquartile range 3.5-30.1) there were 2 ipsilateral strokes and 3 ipsilateral TIAs. The average annual event rate was 7.7%. A lipid-rich necrotic core (HR 7.21; 95% CI 1.12-46.28; p = 0.037), sonographic progression of the stenosis (HR 7.00; 95% CI 1.13-41.34; p = 0.036), history of stroke (HR 11.03; 95% CI 1.23-99.36; p = 0.032), and the volume of clinically asymptomatic ischemic brain lesions (HR 1.14/cm(3); 95% CI 1.03-1.25; p = 0.008) predicted cerebrovascular events. Patients on statin therapy at follow-up were at lower risk of events (HR 0.17; 95% CI 0.03-1.00; p = 0.05).

CONCLUSIONS

In addition to medical history and sonographic findings, a lipid-rich necrotic core within the plaque turned out as a predictor of cerebrovascular events. Therefore, MR imaging of carotid plaques deserves further attention and might be helpful to improve risk stratification of asymptomatic carotid disease. The identified predictors could be combined in a risk model and tested in larger prospective studies.