Impact of Admission Glucose and Diabetes on Recanalization and Outcome after Intra-Arterial Thrombolysis for Ischaemic Stroke

Background

Stroke patients with diabetes and admission hyperglycaemia have worse outcomes than non-diabetics, with or without intravenous thrombolysis. Poor vessel recanalization was reported in diabetics treated with intravenous thrombolysis.

Aims

This study aimed to determine the impact of admission glucose and diabetes on recanalization and outcome after intra-arterial thrombolysis.

Methods

We analysed 389 patients (213 men, 176 women) treated with intra-arterial thrombolysis. The association of diabetes and admission glucose value with recanalization, outcome, mortality, and symptomatic intracranial haemorrhage was determined. Recanalization was classified according to thrombolysis in myocardial infarction grades. Outcome was measured using the modified Rankin Scale at three-months and categorized as favourable (modified Rankin Scale 0–2) or poor (modified Rankin Scale 3–6).

Results

The rate of partial or complete recanalization (thrombolysis in myocardial infarction 2–3) did not differ between patients with and without diabetes (67% vs. 66%; P = 1·000). Mean admission glucose values were similar in patients with poor recanalization (thrombolysis in myocardial infarction 0–1) and patients with partial or complete recanalization (thrombolysis in myocardial infarction 2–3; 7·3 vs. 7·3 mmol/l; P = 0·746). Follow-up at three-months was obtained in 388 of 389 patients. Clinical outcome was favourable (modified Rankin Scale 0–2) in 189 patients (49%) and poor (modified Rankin Scale 3–6) in 199 patients (51%). Mortality at three-months was 20%. Diabetics were more likely to have poor outcome (72% vs. 48%; P = 0·001) and to be dead (30% vs. 19%; P = 0·044) at three-months. After multivariable analysis, there remained an independent relationship between diabetes and outcome ( P = 0·003; odds ratio 3·033, 95% confidence interval 1·452–6·336), but not with mortality ( P = 0·310; odds ratio 1·436; 95% confidence interval 0·714–2·888). Moreover, higher age ( P = 0·001; odds ratio 1·039; 95% confidence interval 1·017–1·061), higher baseline National Institutes of Health Stroke Scale score ( P < 0·0001; odds ratio 1·130; 95% confidence interval 1·079–1·182), location of vessel occlusion as categorical variable ( P < 0·0001), poor collaterals ( P = 0·02; odds ratio 1·587; 95% confidence interval 1·076–2·341), poor vessel recanalization ( P < 0·0001; odds ratio 4·713; 95% confidence interval 2·627–8·454), and higher leucocyte count ( P = 0·032; odds ratio 1·094; 95% confidence interval 1·008–1·188) were independent baseline predictors of poor outcome. Higher admission glucose was associated with poor outcome ( P = 0·006) and mortality ( P < 0·0001). After multivariate analyses, glucose remained independently associated with poor outcome ( P = 0·019; odds ratio 1·150; 95% confidence interval 1·023-1-292) and mortality ( P = 0·005; odds ratio 1·183; 95% confidence interval 1052–1·331). The rate of symptomatic intracranial haemorrhage was similar in diabetics and non-diabetics (6·7% vs. 4·6%; P = 0·512). Mean admission glucose was higher in patients with symptomatic intracranial haemorrhage than without (8·58 vs. 7·26 mmol/l; P = 0·010). Multivariable analysis confirmed an independent association between admission glucose and symptomatic intracranial haemorrhage ( P = 0·027; odds ratio 1·187; 95% confidence interval 1·020–1·381).

Conclusions

Diabetes and glucose value on admission did not influence recanalization after intra-arterial thrombolysis; nevertheless, they were independent predictors of poor outcome after intra-arterial thrombolysis and a higher admission glucose value was an independent predictor of symptomatic intracranial haemorrhage. This indicates that factors on the capillary, cellular, or metabolic level may account for the worse outcome in patients with elevated glucose value and diabetes.

The risk of paradoxical embolism (RoPE) study: initial description of the completed database

BACKGROUND

Detecting a benefit from closure of patent foramen ovale in patients with cryptogenic stroke is hampered by low rates of stroke recurrence and uncertainty about the causal role of patent foramen ovale in the index event. A method to predict patent foramen ovale-attributable recurrence risk is needed. However, individual databases generally have too few stroke recurrences to support risk modeling. Prior studies of this population have been limited by low statistical power for examining factors related to recurrence.

AIMS

The aim of this study was to develop a database to support modeling of patent foramen ovale-attributable recurrence risk by combining extant data sets.

METHODS

We identified investigators with extant databases including subjects with cryptogenic stroke investigated for patent foramen ovale, determined the availability and characteristics of data in each database, collaboratively specified the variables to be included in the Risk of Paradoxical Embolism database, harmonized the variables across databases, and collected new primary data when necessary and feasible.

RESULTS

The Risk of Paradoxical Embolism database has individual clinical, radiologic, and echocardiographic data from 12 component databases, including subjects with cryptogenic stroke both with (n = 1925) and without (n = 1749) patent foramen ovale. In the patent foramen ovale subjects, a total of 381 outcomes (stroke, transient ischemic attack, death) occurred (median follow-up 2·2 years). While there were substantial variations in data collection between studies, there was sufficient overlap to define a common set of variables suitable for risk modeling.

CONCLUSION

While individual studies are inadequate for modeling patent foramen ovale-attributable recurrence risk, collaboration between investigators has yielded a database with sufficient power to identify those patients at highest risk for a patent foramen ovale-related stroke recurrence who may have the greatest potential benefit from patent foramen ovale closure.

Adverse effect of early epileptic seizures in patients receiving endovascular therapy for acute stroke

BACKGROUND AND PURPOSE

The aim of this study was to analyze epileptic seizures and their impact on outcome in patients with stroke treated with endovascular therapy.

METHODS

From December 1992 to December 2010 we managed 805 patients with stroke with endovascular therapy. Epileptic seizures, bleeding complications, and 3-month outcomes were recorded prospectively. Outcomes of patients with early seizures (within 24 hours of stroke onset) and patients with late seizures (>24 hours after stroke) were compared with outcomes of seizure-free patients using uni- and multivariable statistics.

RESULTS

Forty-four of 805 patients (5.5%) had seizures between stroke onset and 3-month follow-up, 26 patients early and 18 late. Outcome of patients with late seizures and seizure-free patients was similar (P=0.144 and 0.807). Patients with early seizures had higher baseline National Institutes of Health Stroke Scale (P=0.023) and were younger (P=0.021) than seizure-free patients. Their mortality rate was 50% compared with 22.3% of the seizure free-patients (P=0.003), and less patients reached a favorable outcome (modified Rankin Scale 0-2): 15.4% and 46.8%, respectively (P=0.001). Early seizures independently predicted an unfavorable outcome (P=0.014; OR, 4.749; 95% CI, 0.376-3.914) and increased mortality (P=0.001; OR, 5.861; 95% CI, 0.770-2.947) in multiregression analysis. Patients with early seizures had a 1.6-fold higher risk for unfavorable outcome and a 2.2-fold higher risk for death compared with seizure-free patients.

CONCLUSIONS

Seizures within 24 hours of stroke onset were associated with worse outcome in patients with stroke undergoing endovascular therapy. Our findings confirm a need for trials for prophylactic anticonvulsive treatment in patients receiving endovascular therapy for acute stroke.

CO(2)-Dependent vasomotor reactivity of cerebral arteries in patients with severe traumatic brain injury: time course and effect of augmentation of cardiac output with dobutamine

Failing cerebral blood flow (CBF) autoregulation may contribute to cerebral damage after traumatic brain injury (TBI). The purpose of this study was to describe the time course of CO(2)-dependent vasoreactivity, measured as CBF velocity in response to hyperventilation (vasomotor reactivity [VMR] index). We included 13 patients who had had severe TBI, 8 of whom received norepinephrine (NE) based on clinical indication. In these patients, measurements were also performed after dobutamine administration, with a goal of increasing cardiac output by 30%. Blood flow velocity was measured with transcranial Doppler ultrasound in both hemispheres. All patients except one had an abnormal VMR index in at least one hemisphere within the first 24 h after TBI. In those patients who did not receive catecholamines, mean VMR index recovered within the first 48 to 72 h. In contrast, in patients who received NE within the first 48 h period, VMR index did not recover on the second day. Cardiac output and mean CBF velocity increased significantly during dobutamine administration, but VMR index did not change significantly. In conclusion, CO(2) vasomotor reactivity was abnormal in the first 24 h after TBI in most of the patients, but recovered within 48 h in those patients who did not receive NE, in contrast to those eventually receiving the drug. Addition of dobutamine to NE had variable but overall insignificant effects on CO(2) vasomotor reactivity.

Impact of Thrombolysis on Stroke Outcome at 12 Months in a Population

Background and Purpose—

Thrombolysis improves outcome of patients with acute ischemic stroke, but it is unknown whether thrombolysis has a measurable effect on long-term outcome in a defined population.

Methods—

We prospectively assessed demographic data, management, and outcome of acute ischemic stroke patients admitted within 48 hours to 18 primary care hospitals of the canton of Bern (969 299 inhabitants) during 12 months. Blinded follow-up was obtained at 3 and 12 months. Predictors of mortality and favorable outcome (modified Rankin Scale score ≤2) at 3 and 12 months using logistic regression were analyzed.

Results—

From December 2007 to December 2008, 807 patients (mean age, 72 years) were included. Median National Institutes of Health Stroke Scale score on admission was 5; 107 patients (13%) received intravenous, intra-arterial, or mechanical thrombolysis. Estimated cumulative mortality at 3 months was 20.6% and at 12 months 27.4%. Age 75 years or older, higher National Institutes of Health Stroke Scale scores, and higher Charlson comorbidity index were independent predictors of mortality at 3 and 12 months. Estimated favorable outcome at 3 months was 48.2% and at 12 months was 44.6%. Thrombolysis was the only modifiable independent predictor of favorable outcome at 3 (relative risk, 1.49; 95% CI, 1.18–1.89) and 12 months (relative risk, 1.59; 95% CI, 1.24–2.04), whereas age younger than 75 years, male gender, National Institutes of Health Stroke Scale score <4, and lower Charlson comorbidity index were nonmodifiable predictors.

Conclusions—

Thirteen percent of acute ischemic stroke patients admitted within 48 hours to Bernese hospitals underwent thrombolysis, which exerted a measurable effect on 3-month outcome in this population. This effect was sustained at 12 months. Age, stroke severity, Charlson comorbidity index, and male gender were independent nonmodifiable predictors of outcome.

Endovascular therapy of 623 patients with anterior circulation stroke

BACKGROUND AND PURPOSE

Endovascular therapy of acute ischemic stroke has been shown to be beneficial for selected patients. The purpose of this study is to determine predictors of outcome in a large cohort of patients treated with intra-arterial thrombolysis, mechanical revascularization techniques, or both.

METHODS

We prospectively acquired data for 623 patients with acute cerebral infarcts in the carotid artery territory who received endovascular treatment at a single center. Logistic regression analysis was performed to determine predictors of outcome.

RESULTS

Median National Institutes of Health Stroke Scale (NIHSS) at admission was 15. Partial or complete recanalization was achieved in 70.3% of patients; it was independently associated with hypercholesterolemia (P=0.02), absence of coronary artery disease (P=0.023), and more proximal occlusion site (P<0.0001). After 3 months, 80.5% of patients had survived, and 48.9% of patients reached favorable outcome (modified Rankin scale score 0-2). Good collaterals (P<0.0001), recanalization (P=0.023), hypercholesterolemia (P=0.03), lower NIHSS at admission (P=0.001), and younger age (P<0.0001) were independent predictors for survival. More peripheral occlusion site (P<0.0001), recanalization (P<0.0001), hypercholesterolemia (P=0.002), good collaterals (P=0.002), lower NIHSS (P<0.0001), younger age (P<0.0001), absence of diabetes (P=0.002), and no previous antithrombotic therapy (P=0.036) predicted favorable outcome. Time to treatment was only a predictor of outcome, when collaterals were excluded from the model. Symptomatic intracerebral hemorrhage occurred in 5.5% and was independently predicted by poor collaterals (P=0.004).

CONCLUSIONS

Several independent predictors for outcome and complications were identified. Unlike in intravenous thrombolysis trials, time to treatment was a predictor of outcome only when collaterals were excluded from the model, indicating the important role of collaterals for the time window.

Abstract 84: An Index to Identify Cryptogenic Stroke Patients whose Stroke is likely Attributable to Patent Foramen Ovale

Background: A patent foramen ovale (PFO) discovered in the setting of a cryptogenic stroke (CS) may be incidental or pathogenic. Based on Bayes theorem, the proportion of CS that is PFO-attributable among patients found to have a PFO has been shown to be related to PFO prevalence in CS versus control patients. However, the prevalence of PFO in CS patients is itself dependent on the presence or absence of other risk factors. We exploited this relationship to create an index to stratify CS patients with PFO by their likelihood that the CS is PFO-attributable.

Methods This project is part of the Risk of Paradoxical Embolism (RoPE) Study, an international, multicenter collaboration that has combined data for patients with CS and cryptogenic TIA who have known PFO status from 12 component studies (n=3665). For this study, we included those subjects within the 7 databases enrolling subjects both with and without PFO (n=3023). We used generalized linear mixed models to identify variables associated with the presence of a PFO, accounting for clustering within study. Based on this model, we created a simple index. Bayes theorem was used to estimate the PFO-attributable fraction in each stratum assuming a PFO prevalence in the general population of ∼25%.

Results: Variables negatively associated with the presence of a PFO included: age (odds ratio [OR] = 0.97 per 1 year increase, p <0.0001); diabetes (OR= 0.65, p < 0.001); hypertension (OR =0.68, p < 0.0001); smoking (OR = 0.70, p<0.60); prior stroke or TIA (OR = 0.78, p=0.04). Cortical stroke on neuroimaging (OR = 1.46, p < 0.001) was also associated with PFO. Based on this, a simple index was created in which the absence of each stroke risk factor was assigned a point, with age dichotomized at 50 years. PFO prevalence in each stratum is shown in the table for patients < age 60, i.e. the subset of patients likely to be considered for PFO closure trials.

Conclusion: Even among CS patients in the younger age range considered eligible for closure trials, there is considerable heterogeneity in the distribution of risk factors for stroke and other characteristics that identify subgroups of CS patients with variation in PFO prevalence. This reflects substantial and clinically important variation in the probability that a discovered PFO is likely to be pathogenic rather than incidental. This score may be useful in selecting patients for closure trials, or for stratification within trials, particularly if combined with a recurrence risk model.

Abstract 3430: Superficial and Large Infarcts on Neuroimaging in Patients with Cryptogenic Stroke are Associated with the Presence or Absence of Patent Foramen Ovale

Introduction We aim to determine whether radiological findings are associated with patent foramen ovale (PFO) among patients with cryptogenic stroke (CS). Radiological findings associated with the presence of a PFO may represent stroke patterns typical of paradoxical embolism which may be distinct from other mechanisms of CS.

Methods This project is part of the Risk of Paradoxical Embolism (RoPE) Study, an international collaboration that has combined individual-level data for subjects with CS and TIA who have known PFO status from 12 component studies (n=3665). For this study 7 databases (n=3023) were used that included subjects with and without PFO, and with radiologic data. Five variables were tested for their relationship with PFO status: 1) protocol-defined large vs. small infarct , 2) Index stroke seen on imaging, 3) superficial vs. deep infarct, 4) multiple index lesions, 5) Prior stroke, i.e. chronic infarct on index imaging.

Results are presented in the table . Odds ratios and p-values are adjusted for age, database, sex, diabetes, hypertension, smoking, and history of stroke/TIA. This is the largest study to report the radiological characteristics of patients with CS who are known to have, or not to have, a PFO. Some prior studies had null findings but were limited by small sample size and low statistical power. Because CS unrelated to PFO may also be embolic, the radiological pattern of paradoxical embolism may not be expected to be different from other cryptogenic emboli. Despite this, PFOs were significantly more common in CS patients with large and with superficial infarcts. Conversely, infarcts that were small and deep were associated with PFO absence. This suggests that lacunar disease may account for some non-PFO related CS.

Conclusion Participants were significantly more likely to have a PFO if they had 1) an index stroke seen on neuroimaging, 2) a large stroke, 3) a superficial stroke; there was no effect of the variables prior ( i.e. chronic) infarct or multiple vs. single infarcts. Further analyses may help to clarify the ability of neuroimaging to predict the finding of a PFO.

Long-term propensity score-matched comparison of percutaneous closure of patent foramen ovale with medical treatment after paradoxical embolism

BACKGROUND

Patients with ischemic stroke or transient ischemic attack presumably related to patent foramen ovale (PFO) are at risk for recurrent cerebrovascular events. Differences in long-term clinical outcome were investigated among patients with percutaneous PFO closure and those who received medical treatment.

METHODS AND RESULTS

Between 1994 and 2000, 308 consecutive patients with cerebrovascular events presumably related to PFO underwent either percutaneous PFO closure (150 patients) or medical treatment (158 patients). Patients were followed up prospectively for up to 15 years. Seven patients were lost during follow-up. The primary outcome was a composite of stroke, transient ischemic attack, or peripheral embolism. We analyzed 103 propensity score-matched pairs of patients who underwent percutaneous PFO closure or medical treatment. At a median follow-up of 9 years, the primary composite outcome occurred in 11 patients slated to PFO closure (11%) and 22 patients slated to medical treatment (21%; hazard ratio=0.43; 95% confidence interval=0.20-0.94; P=0.033). The treatment effect was driven by a decrease in the risk of transient ischemic attack of 5% versus 14%, respectively (hazard ratio=0.31; 95% confidence interval=0.10-0.94; P=0.039). The risk of all-cause (6% in both groups) and cardiovascular (3% in both groups) mortality appeared to be identical.

CONCLUSION

In this long-term observational, propensity score-matched study, percutaneous PFO closure was more effective than medical treatment for the secondary prevention of recurrent cerebrovascular events among patients with PFO-related transient ischemic attack or stroke.

Intra-arterial thrombolysis for acute ischemic stroke in octogenarians

BACKGROUND

It is unclear whether octogenarians benefit from intra-arterial thrombolysis (IAT) for the treatment of acute ischemic stroke (AIS). The aim of the present study was to compare baseline characteristics, clinical outcome and complications of patients aged ≥80 with those of patients aged <80 years.

METHODS

Forty-three octogenarians and 524 younger patients with AIS were treated with IAT. The modified Rankin scale (mRS) score was used to assess 3-month outcome.

RESULTS

There was a female preponderance among octogenarians (63 vs. 37%, p = 0.015). Stroke severity, occlusion site, and time from stroke onset to IAT did not differ between the groups. Good recanalization (TIMI 2-3) was achieved in 65% of older and in 71% of younger patients (p = 0.449). Rates of symptomatic intracranial hemorrhage (ICH) were 6% in patients <80 years and 2% in octogenarians (p = 0.292). Favorable outcome (mRS 0-2) was less frequent among octogenarians (28 vs. 46%, p = 0.019), while mortality was higher (40 vs. 22%, p = 0.008). Octogenarians died more often from extracerebral complications than younger patients (59 vs. 27%, p = 0.008).

CONCLUSIONS

Compared with younger patients, octogenarians did not have a significantly increased risk of symptomatic ICH after IAT. Although favorable outcome was less frequent and mortality rates were higher, IAT appeared to be safe in octogenarians. It seems reasonable to include octogenarians in randomized clinical trials to assess the balance of risk and benefit of IAT in this patient group.

Intracranial Hemorrhage, Outcome, and Mortality After Intra-Arterial Therapy for Acute Ischemic Stroke in Patients Under Oral Anticoagulants

Background and Purpose—

Use of intravenous tissue-type plasminogen activator (IV tPA) for acute ischemic stroke is restricted to patients with an international normalized ratio (INR) less than 1.7. However, a recent study showed increased risk of symptomatic intracranial hemorrhage after IV tPA use in patients with oral anticoagulants (OAC) even with an INR less than 1.7. The present study assessed the risk of symptomatic intracranial hemorrhage, clinical outcome, and mortality after intra-arterial therapy (IAT) in patients with and without previous use of OAC.

Methods—

Consecutive patients treated with IAT from December 1992 to October 2010 were included. Clinical outcome and mortality were assessed 90 days after stroke onset. Patients with and without previous use of OAC were compared.

Results—

Overall, 714 patients were treated with IAT. Twenty-eight patients (3.9%) were under OAC at time of symptom onset. Median INR in the OAC group was 1.79 (interquartile range [IQR], 1.41–2.3) and 1.01 (IQR, 1.0–1.09; P <0.0001) in the group without OAC. Patients treated with OAC at admission underwent more often mechanical-only IAT than did patients without OAC (46.4% versus 12.8%; P <0.0001). Comparing patients with and without previous use of OAC, we did not find any statistical difference in the rate of symptomatic intracranial hemorrhage (7.1% versus 6.0%; P =0.80), unfavorable outcome (modified Rankin Scale score, 3–6; 67.9% versus 50.9%; P =0.11), and mortality (17.9% versus 21.6%; P =0.58).

Conclusions—

Previous use of OAC did not significantly increase the risk of symptomatic intracranial hemorrhage after IAT or the risk of unfavorable outcome and mortality 90 days after IAT.

Patent foramen ovale may be causal for the first stroke but unrelated to subsequent ischemic events

BACKGROUND AND PURPOSE

Studies with very long follow-up are scarce in patients with cryptogenic stroke and patent foramen ovale (PFO). Little is known about the etiology of recurrent cerebrovascular events (CVE) in PFO patients.

METHODS

We collected information on recurrent CVE in 308 patients with cryptogenic stroke and PFO and sought to determine concurrent stroke causes that had emerged or been newly detected since the index event. One hundred fifty-eight patients received aspirin (48%), clopidogrel (2%), or oral anticoagulants (50%; medical group). One hundred fifty patients underwent percutaneous PFO closure (closure group).

RESULTS

Mean age at index event was 50 years (SD 13). In 33% of patients, the index stroke or transient ischemic attack was preceded by at least 1 CVE. Mean follow-up was 8.7±4.0 years. During follow-up, 32 recurrent CVE (13 strokes and 19 transient ischemic attacks) occurred in the medical and 16 recurrent CVE (8 strokes and 8 transient ischemic attacks) in the closure group. Concurrent etiologies were identified for 12 recurrent CVE in the medical group (38%): large artery disease (9%), small artery disease (6%), cardioembolism (13%), cerebral vasculitis (3%), and antiphospholipid-antibody-syndrome (6%). In the closure group, 7 recurrent CVE had a concurrent etiology (44%): large artery disease (6%), small artery disease (19%), cardioembolism (13%), and thrombophilic disorder (6%). The frequency of concurrent etiologies did not differ between patients with recurrent CVE under medical treatment and those undergoing PFO closure (P=0.68).

CONCLUSIONS

Concurrent etiologies are identified for more than one third of recurrent ischemic events in patients with cryptogenic stroke, casting doubt on the sole causal role of PFO.

Decompressive craniectomy after intra-arterial thrombolysis: safety and outcome

OBJECTIVES

Data on decompressive craniectomy (DC) after intra-arterial thrombolysis (IAT) for treatment of malignant middle cerebral artery (MCA) stroke are lacking.

METHODS

The authors compared consecutive patients with middle cerebral artery (MCA) strokes who underwent decompressive craniectomy (DC) after IAT with DC patients without prior thrombolysis.

RESULTS

Thirty of 2395 consecutive patients with acute ischaemic stroke or transient ischaemic attack were treated with DC because of space-occupying oedema 12-72 h after symptom onset. Fifteen patients underwent intra-arterial thrombolysis (IAT) prior to DC. Baseline characteristics did not differ between thrombolysed and non-thrombolysed patients except for lower National Institute of Health Stroke Scale score in non-thrombolysed patients (median National Institute of Health Stroke Scale 17 vs. 14, p=0.033). The outcome at 3 months was favourable (modified Rankin scale 0-3) in seven (47%) thrombolysed patients and in four (27%) non-thrombolysed patients (p=0.45). Mortality and major complications after DC did not differ between the two groups (p>0.05). Older age (p=0.037) and previous hypertension (p=0.047) independently predicted unfavourable outcome in DC patients, but not IAT prior DC.

CONCLUSIONS

There was no difference of outcome of patients with DC with or without prior IAT. DC after IAT did not cause any more complications than DC without prior thrombolysis.

Outcome after thrombolysis for acute isolated posterior cerebral artery occlusion

BACKGROUND

To date, there is limited data on intra-arterial thrombolysis (IAT) and intravenous thrombolysis (IVT) for isolated posterior cerebral artery (PCA) occlusion. We aimed to evaluate recanalization, outcome and quality of life in patients who undergo thrombolysis for isolated PCA occlusion.

METHODS

Analysis of 9 patients treated with IAT and 9 patients treated with IVT with short-term (3 months) outcome and long-term (median 23 months) outcome after IAT.

RESULTS

9 of 546 patients treated with IAT (4 women and 5 men; median age 66 years) had isolated PCA occlusion. Median baseline National Institute of Health Stroke Scale (NIHSS) score on admission was 9. Eight patients presented with visual field defects and variable additional symptoms. One patient suffered bithalamic infarction. Median time to treatment was 5.8 h. Recanalization was complete in 2, partial in 2, minimal in 2, and not achieved in 3 patients. Recanalization tended to be better when the microcatheter was placed in or close to the thrombus. We observed no major complications, and 3 months outcome was favorable (modified Rankin Scale score 0-2) in 67% of the patients after IAT. During the same period, 9 patients with PCA occlusion were treated with IVT with 89% favorable clinical outcomes at 3 months. At long-term follow-up after IAT, neuropsychological domains were more severely impaired than other neurologic functions.

CONCLUSION

IAT is a feasible treatment of isolated PCA strokes. Clinical outcome was favorable in the majority of patients after IAT and IVT. No major complications were observed. Further studies are needed to compare IAT and IVT for isolated PCA stroke.

Three-month and long-term outcomes and their predictors in acute basilar artery occlusion treated with intra-arterial thrombolysis

BACKGROUND AND PURPOSE

Intra-arterial thrombolysis can be used for treatment of basilar artery occlusion. Predictors of outcome before initiation of treatment are of special interest.

METHODS

From 1992 to 2010, we treated 106 consecutive patients with basilar artery occlusion with intra-arterial thrombolysis. Baseline characteristics, treatment, clinical course, and 3-month and long-term outcomes (≥12 months) were assessed. Outcome parameters were vessel recanalization after treatment, complications, modified Rankin scale (mRS) score, and mortality after 3 months and in the long-term.

RESULTS

At 3 months, clinical outcome was good (mRS score, 0-2) in 33.0% of the patients and moderate (mRS score, 3) in 11.3%. Mortality was 40.6%. Partial or complete recanalization was achieved in 69.8% of the patients, and symptomatic intracranial hemorrhage occurred in 1 patient (0.9%). Between 3-month and long-term follow-up, 22 survivors (40.8%) showed clinical improvement of at least 1 point on the mRS score, 29 (53.7%) were functionally unchanged, and 3 (5.7%) showed functional worsening (P<0.0001). Multivariate analysis identified diabetes as a predictor of poor vessel recanalization (P=0.028). Low baseline National Institutes of Health Stroke Scale score was identified as a predictor of good or moderate clinical outcome (P<0.0001) and survival (P=0.001) at 3 months, and younger age was identified as an additional predictor of survival (P=0.012). For prediction of long-term clinical outcome, age was also an independent predictor (P=0.018).

CONCLUSIONS

In our series, intra-arterial thrombolysis as treatment of basilar artery occlusion was safe. National Institutes of Health Stroke Scale score at admission and age were identified as predictors of outcome, and these predictors should be considered for treatment allocation in future randomized trials.

Posterior versus anterior circulation strokes: comparison of clinical, radiological and outcome characteristics

BACKGROUND AND PURPOSE

Physicians treating patients with posterior circulation strokes (PCS) tended to debate more on whether or not to introduce anticoagulation rather than performing investigations to identify stroke aetiology, as in patients with anterior circulation strokes (ACS). Recent findings suggest that stroke aetiologies of PCS and ACS are more alike than dissimilar, suggesting that PCS deserve the same investigations as ACS. The characteristics and current diagnostic evaluation between patients with PCS and ACS were compared.

METHODS

312 consecutive patients with first ever ACS and 93 patients with first ever PCS were prospectively analysed.

RESULTS

Patients with ACS and PCS did not differ in terms of demographic characteristics, prevalence of vascular risk factors, diagnostic evaluation or stroke aetiology. The median National Institutes of Health Stroke Scale score was 8 in ACS and 4 in PCS (p=0.004). Brain imaging revealed more often pathological findings in ACS than PCS. The proportion of non-thrombolysed patients with a favourable clinical outcome (modified Rankin score 0-2) was similar in ACS and PCS (67.0% vs 78.4%; p=0.08). In non-thrombolysed patients, stroke severity was an independent predictor of clinical outcome both in ACS (OR 1.60, 95% CI 1.2 to 2.1; p<0.0001) and in PCS (OR 1.22, 95% CI 1.03 to 1.44; p=0.02) while age predicted poor outcome only in ACS (OR 1.11, 95% CI 1.01 to 1.22; p=0.007). In thrombolysed patients, stroke severity was the only outcome predictor in ACS (OR 1.14, 95% CI 1.04 to 1.25; p=0.004) while we identified no statistically relevant predictor of PCS outcome.

CONCLUSIONS

In PCS and ACS, baseline variables, aetiology and outcome are more alike than different.

What is a minor stroke?

BACKGROUND AND PURPOSE

The term "minor stroke" is often used; however a consensus definition is lacking. We explored the relationship of 6 "minor stroke" definitions and outcome and tested their validity in subgroups of patients.

METHODS

A total of 760 consecutive patients with acute ischemic strokes were classified according to the following definitions: A, score < or = 1 on every National Institutes of Health Stroke Scale (NIHSS) item and normal consciousness; B, lacunar-like syndrome; C, motor deficits with or without sensory deficits; D, NIHSS < or = 9 excluding those with aphasia, neglect, or decreased consciousness; E, NIHSS < or = 9; and F, NIHSS < or = 3. Short-term outcome was considered favorable when patients were discharged home, and favorable medium-term outcome was defined as a modified Rankin Scale score of < or = 2 at 3 months. The following subgroup analyses were performed by definition: sex, age, anterior versus posterior and right versus left hemispheric stroke, and early (0 to 6 hours) versus late admission (6 to 24 hours) to the hospital.

RESULTS

Short-term and medium-term outcomes were most favorable in patients with definition A (74% and 90%, respectively) and F (71% and 90%, respectively). Patients with definition C and anterior circulation strokes were more likely to be discharged home than patients with posterior circulation strokes (P=0.021). The medium-term outcome of older patients with definition E was less favorable compared with the outcome of younger ones (P=0.001), whereas patients with definition A, D, and F did not show different outcomes in any subgroup.

CONCLUSIONS

Patients fulfilling definition A and F had best short-term and medium-term outcomes. They would be best suited to the definition of "minor stroke."

Long-term outcome of symptomatic severe ostial vertebral artery stenosis (OVAS)

INTRODUCTION

The optimal management of patients with symptomatic severe ostial vertebral artery stenosis (OVAS) is currently unclear. We analyzed the long-term outcome of consecutive patients with OVAS who received either medical treatment (MT) or vertebral artery stenting (VAS).

METHODS

Thirty-nine (>70%) patients with severe OVAS were followed for a mean period of 2.8 years. The decision for VAS (n = 10) or MT (n = 29) was left to the clinician. The Kaplan-Meier method was used to assess the risk of recurrent stroke, transient ischemic attack (TIA), or death over the study period.

RESULTS

Patients in the VAS group were significantly younger and more likely to have bilateral VA disease (P = 0.04 and P = 0.02). VAS was successfully performed in all ten patients. The periprocedural risk within 30 days was 10% (one TIA). The overall restenosis rate was 10%. One restenosis occurred after 9 months in a patient treated with bare-metal stent. At 4 years of follow-up, VAS showed a nonsignificant trend toward a lower risk for the combined endpoint of TIA and stroke in posterior circulation compared to medical treatment (10% vs. 45%, P = 0.095; relative risk (RR) = 0.24, 95% confidence interval (CI) 0.031-1.85). Patients with bilateral VA disease had a significantly lower recurrence risk after VAS compared with medical treatment (0% vs. 91% at 4 years, P = 0.004; RR 0.10, 95% CI 0.022-0.49)

CONCLUSION

VAS was performed without permanent complications in this small series of patients with symptomatic severe OVAS. The long-term benefit seems to be confined to patients with bilateral but not to those with unilateral VA disease.

G protein-coupled receptor-induced sensitization of phospholipase C stimulation by receptor tyrosine kinases

Activation of stably expressed M(2) and M(3) muscarinic acetylcholine receptors (mAChRs) as well as of endogenously expressed lysophosphatidic acid and purinergic receptors in HEK-293 cells can induce a long lasting potentiation of phospholipase C (PLC) stimulation by these and other G protein-coupled receptors (GPCRs). Here, we report that GPCRs can induce an up-regulation of PLC stimulation by receptor tyrosine kinases (RTKs) as well and provide essential mechanistic characteristics of this sensitization process. Pretreatment of HEK-293 cells for 2 min with carbachol, a mAChR agonist, lysophosphatidic acid, or ATP, followed by agonist washout, strongly increased (by 2-3-fold) maximal PLC stimulation (measured >/=40 min later) by epidermal growth factor and platelet-derived growth factor, but not insulin, and largely enhanced PLC sensitivity to these RTK agonists. The up-regulation of RTK-induced PLC stimulation was cycloheximide-insensitive and was observed for up to approximately 90 min after removal of the GPCR agonist. Sensitization of receptor-induced PLC stimulation caused by prior M(2) mAChR activation was fully prevented by pertussis toxin and strongly reduced by expression of Gbetagamma scavengers. Furthermore, inhibition of conventional protein kinase C (PKC) isoenzymes and chelation of intracellular Ca(2+) suppressed the sensitization process, while overexpression of PKC-alpha, but not PKC-betaI, further enhanced the M(2) mAChR-induced sensitization of PLC stimulation. None of these treatments affected acute PLC stimulation by either GPCR or RTK agonists. Taken together, short term activation of GPCRs can induce a strong and long lasting sensitization of PLC stimulation by RTKs, a process apparently involving G(i)-derived Gbetagammas as well as increases in intracellular Ca(2+) and activation of a PKC isoenzyme, most likely PKC-alpha.