[Antiplatelet therapy for secondary prevention of cerebral infarction]

Antiplatelet therapy is indicated for secondary prevention of non cardioembolic ischemic stroke. The administration of aspirin (or other antiplatelet agents) as an adjunctive therapy within 24 hours of intravenous fibrinolysis is not recommended. In the acute stage, intravenous administration of ozagrel sodium (thromboxane A2 synthase inhibitor) is approved in Japan. Dual antiplatelet therapy such as aspirin plus clopidogrel may be acceptable according to the data of CHANCE. In the chronic stage of cerebral infarction, monotherapy (aspirin, clopidogrel or cilostazol) is recommended. Selection among 3 agents should be based on relative effectiveness, safety, cost, patients' characteristics, and patients' preference. Dual antiplatelet therapy is limited in patients with high risk, post carotid stenting, etc.

Abstract T MP1: Predictive Factors of Favorable Outcome in Patients With Acute Large Vessel Occlusion

Background: The data of the nationwide prospective registry of acute cerebral large vessel occlusion (RESCUE-Japan Registry) was analyzed to know the predictive factors of favorable outcome at 90 days

Methods: In this registry, patients with acute cerebral large vessel occlusion admitted within 24 h after onset were prospectively registered. The effect of various factors including endovascular treatment (EVT), intravenous tissue plasminogen activator (IV-tPA), and other medication on favorable outcome (modified Rankin scale 0-2) was analyzed.

Results: A total of 1,315 patients were analyzed. The number of patients in favorable outcome was 422 (32.1%). Logistic regression analysis revealed that higher NIHSS (OR 0.875, 95%CI 0.858-0.894) and advanced age (OR 0.963, 95% CI 0.952-0.975) were significantly related to unfavorable outcome (Fig. 1). In contrast, IV-tPA (OR 2.489, 95% CI 1.867-3.319), EVT (OR 1.375, 95% CI 1.013-1.865), and free radical scavenger, edaravon, (OR 1.483, 95% CI 1.027-2.143) were significantly associated with favorable outcome. Combination with IV-tPA or EVT with free radical scavenger was better than without it (Fig. 2).

Conclusions: This analysis indicated that IV-tPA, EVT and free radical scavenger were effective to obtain favorable outcome in the patients with acute large vessel occlusion. Combination with free radical scavenger was also effective.

Abstract 118: Diffusion Lesion Volume Reduction after Recanalization Therapy for Anterior Circulation Stroke with Major Vessel Occlusion: Analysis from the RESCUE-Japan Registry Study

Objective: Although Diffusion-weighted imaging (DWI) lesions are commonly irreversible, DWI lesion volume reduction (DVR) is occasionally observed. We investigated clinical significance and predictors of DVR in acute stroke patients with major vessel occlusion receiving recanalization therapy (RT).

Methods: The Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism (RESCUE)-Japan registry prospectively registered 1,442 stroke patients with major vessel occlusion who were admitted to 84 Japanese stroke centers within 24 hours after onset from July 2010 to June 2011. We retrospectively analyzed all patients with the internal carotid artery or middle cerebral artery (M1 or M2 segments occlusions receiving RT and undergoing MRI both on admission and at 24 hours after onset from the registry. We defined DVR as a 1 or more-point reduction of the DWI-Alberta Stroke Program Early CT Score (ASPECTS), and CT-DWI mismatch (CTDM) as a 2 or more-point lower DWI-ASPECTS than CT-ASPECTS on admission. Reperfusion was defined as TICI grade 2b-3 on catheter angiography or modified Mori grade 3 on MRA immediately after RT. Dramatic recovery (DR) was defined as a 10 or more-point reduction or a total NIHSS score of 0-1 at 24 hours, and favorable outcome (FO) defined as a mRS score 0-2 at 3 months.

Results: A total of 390 patients (215 men, 72 years old,) was included. Median baseline NIHSS score was 16 (IQR 10-19) and median baseline DWI-ASPECTS was 8 (6-9). CTDM was seen in 92 patients (28%) on admission. Intravenous thrombolysis and endovascular therapy were performed in 246 patients (63%) and 223 patients (57%), respectively. Reperfusion was obtained in 170 patients (51%). DVR was seen in 51 patients (13%). Eighty-eight patients (23%) obtained DR and 158 patients (41%) achieved FO. On multivariate analyses, DVR was significantly related to DR (OR 3.8, 95%CI 1.5-10) and FO (4.6, 1.8-12). CTDM was an independent predictor of DVR (OR 2.5, 95% CI 1.1-5.8).

Conclusions: DVR was significantly related to DR and FO. CTDM is a rough predictor of DVR of which area is considered as a “DWI-bright” ischemic penumbra, and might be a useful marker to identify the adequate candidates for RT in spite of relatively large DWI lesions.

Abstract T MP2: Efficacy of Endovascular Therapy in Acute Ischemic Stroke with Major Artery Occlusion of Anterior Circulation -RESCUE-Japan Registry-

Background and Purpose: Efficacy of endovascular therapy (EVT) for acute ischemic stroke (AIS) has not been established. In the Japanese nationwide registry study, we aimed to clarify the impact of EVT on outcomes in AIS patients with major artery occlusion of anterior circulations.

Methods: In the Recovery by Endovascular Salvage for Cerebral Ultra acute Embolism (RESCUE)-Japan registry, 1442 AIS patients with major artery occlusion within 24 hours after the onset were recruited between July 2010 and Jun 2011. Among them, patients with occlusion of anterior circulation were categorized into 2 groups according to site of occluded arteries: internal carotid artery (ICA) or middle cerebral artery (MCA) M1 proximal occlusion as Group P, and MCA M1 distal, M2 or M3 occlusion as Group D. In each group, we examined the relations between EVT and favorable outcome defined as modified Rankin Scale≦2 at 90days.

Results: 482 patients were categorized into Group P (men, 257; mean age,74.6±12.1 years; median baseline National Institute of Health Stroke Scale [NIHSS] score, 18 [IQR 13-22]), and 373 patients were into Group D (men, 204; mean age, 74.2±10.6 years; median baseline NIHSS score, 13 [IQR 7-19]). EVT were performed in 158 patients (32.8%) in Group P and 92 (24.7%) in Group D. In Group P, patients treated with EVT had similar NIHSS score (17.3 vs 17.7) and higher the Alberta Stroke Program Early CT Score on diffusion-weighted imaging (DWI-ASPECTS) on admission (7.4 vs 5.9 P<0.001), and achieved higher rate of favorable outcome (33.5% vs 13.9%, P < 0.001) compared to those without EVT. Whereas in Group D, patients treated with EVT had higher NIHSS (15.0 vs 12.7, P=0.01) and similar DWI-ASPECTS (7.9 vs 7.9), and achieved similar rate of favorable outcome (40.2% vs 45.6%, P=0.40) compared to those without EVT. In a multivariate logistic regression analysis, EVT was related to favorable outcome in Group P (Odds ratio [OR] 2.54, 95% confidence interval [CI] 1.42 - 4.52), but not in Group D (OR 0.74, 95% CI 0.39-1.41).

Conclusions: Endovascular therapy can improve the clinical outcome in AIS patients with ICA or M1 proximal occlusion.

MRI abnormality of the pulvinar in patients with status epilepticus

OBJECTIVE

Recently, magnetic resonance imaging (MRI) abnormalities of the pulvinar in patients with epilepsy have received greater attention, but their occurrence and features have not been fully elucidated. Therefore, we investigated the clinical and radiological features of patients with epilepsy who presented MRI abnormalities of the pulvinar.

PATIENTS AND METHODS

We retrospectively investigated 225 consecutive patients who came to our institute because of seizures and underwent an MRI within 24h. The patients who exhibited pulvinar MRI abnormalities, their profile, seizure type, efficacy of medication, and chronological changes of MRI findings were examined.

RESULTS

Out of the 225 patients who underwent MRI within 24h of seizure, 17 exhibited MRI abnormalities of the pulvinar. All of these 17 patients presented status epilepticus. Bilateral pulvinar diffusion-weighted imaging (DWI) hyperintensity was observed in 3 patients and unilateral pulvinar DWI hyperintensity in the other 14. Out of these 14 patients, 7 exhibited DWI hyperintensity in the ipsilateral cerebral cortex, and 10 patients presented an old lesion due to stroke or trauma.

CONCLUSIONS

Our results demonstrated that the involvement of the pulvinar in status epilepticus is more frequent than expected and consisted of unilateral or bilateral DWI hyperintensities that may completely normalize. These pulvinar MRI abnormalities possibly reflect the epileptogenic hyperexcitation of different cortical areas through their connections with the pulvinar.

CHADS2 Score/CHA2DS2-VASc Score and Major Artery Occlusion in Cardioembolic Stroke Patients with Nonvalvular Atrial Fibrillation

Objective

The associations between the CHADS2 score/ CHA2DS2-VASc score, and the presence of cerebral vessel occlusion on admission were examined in cardioembolic stroke patients with nonvalvular atrial fibrillation.

Methods

The subjects were 546 consecutive patients hospitalized between April 2007 and December 2012 with onset of cardioembolic stroke associated with nonvalvular atrial fibrillation within 24 h. The associations between the CHADS2 score/CHA2DS2-VASc score and the presence of occluded cerebral vessels on magnetic resonance angiography were evaluated retrospectively. Occluded cerebral vessels were classified into the internal carotid artery, middle cerebral artery (M1, M2), basilar artery, and other (anterior cerebral artery [A1], posterior cerebral artery [P1], vertebral artery).

Results

Major artery occlusion was seen in 52% of patients with CHADS2 score 0, 52% of patients with score 1, 57% with score 2, 75% with score 3, and 75% with score ≥4. As for the CHA2DS2-VASc score, major artery occlusion was seen in 62% of patients with score 0, 49% with score 1, 53% with score 2, 53% with score 3, 65% with score 4, 71% with score 5, and 82% with score ≥6. The incidence of concurrent major arterial occlusion increased as both scores rose. When classified by occluded blood vessel, the incidence of concurrent internal carotid artery occlusion increased as both the CHADS2 and CHA2DS2-VASc scores increased.

Conclusion

As the CHADS2 and CHA2DS2-VASs scores increased, the incidence of concurrent major arterial occlusion, particularly internal carotid artery occlusion, increased in patients with cardioembolic stroke associated with nonvalvular atrial fibrillation.

Contrast-induced encephalopathy after coil embolization of an unruptured internal carotid artery aneurysm

A 58-year-old woman developed agraphia and mild right hemiparesis approximately one month after undergoing coil embolization of an unruptured left internal carotid artery aneurysm. MRI performed on day 39 post-coil embolization showed multiple lesions in the white matter with signal hyperintensity on T2-weighted and FLAIR images in the left middle cerebral artery territory. The patient's cerebrospinal fluid exhibited an elevated protein level at 46 mg/dL; however, no other findings suggested another underlying disease. Corticosteroids were administered, and, by day 50 post-coil embolization, the clinical findings and abnormal features on MRI had improved. The patient was therefore diagnosed with contrast-induced encephalopathy after coil embolization.

Cerebral sinovenous thrombosis in a patient with transient eosinophilia

A 67-year-old man with a history of prostatic hypertrophy developed behavioral anomalies and a fever. At admission, diffusion-weighted brain magnetic resonance imaging (MRI) indicated a high-intensity signal lesion on both sides of the cerebral hemisphere. Immediately after hospitalization, he developed paralysis of the left side of the body. Diffusion-weighted MRI indicated hemorrhagic changes in the right and left parietal lobes and right occipital lobe. Magnetic resonance venography indicated superior sagittal sinus occlusion. The blood test results indicated transient eosinophilia. Cases of thrombosis with idiopathic eosinophilia have been reported, but this is the first known case of cerebral sinus thrombosis with transient eosinophilic leukocytosis.

Clinical review of 24 patients with acute cholecystitis after acute cerebral infarction

OBJECTIVE

Acute cholecystitis (AC) after acute cerebral infarction is rare and has not been fully investigated. Because patients with acute cerebral infarction often cannot complain of abdominal pain due to loss of consciousness, hemiparesis and aphasia, delays in diagnosis may increase the severity of the condition. It is clearly important to identify symptoms, reach a diagnosis and provide treatment as soon as possible. The purpose of this study was to investigate the clinical features of AC after acute cerebral infarction.

METHODS

Among the 1,682 patients with acute cerebral infarction admitted to our hospital between April 2007 and July 2012, AC after acute cerebral infarction was diagnosed in 24 (1.4%). Data regarding age, sex, past history, fasting period, period from admission to the onset of cholecystitis, clinical type, severity of cholecystitis, diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score, National Institutes of Health Stroke Scale (NIHSS) score at onset and modified Rankin scale at 90 days were investigated.

RESULTS

The mean age of the 24 patients (15 men, 9 women) was 74.2±11.9 years (range, 45-90 years). The clinical type was atherothrombosis in five patients, lacunar infarction in seven patients, cardiac embolism in 10 patients and dissection in two patients. The past history included atrial fibrillation in 10 (42%) patients, hypertension in 20 (83%) patients and diabetes in 11 (46%) patients. The mean duration of fasting was 10.7 days (range, 1-32 days). The mean interval between the onset of cholecystitis and admission was 8.3 days (range, 0-24 days). The median NIHSS score at onset of cerebral infarction was 10, and 23 (96%) patients were bedridden at the onset of cholecystitis.

CONCLUSION

AC after acute cerebral infarction was frequently observed in the patients with severe hemiparesis and those who were fasted. It is important to identify symptoms, accurately diagnose the condition and provide treatment as soon as possible in order to achieve early ambulation and resumption of food intake using a feeding tube.

Relationship between smoking and responsiveness to clopidogrel in non-cardiogenic ischemic stroke patients

OBJECTIVE

Clopidogrel is used to prevent the recurrence of non-cardiogenic ischemic stroke, but individual responsiveness to the drug varies. Moreover, it is known that smoking, which is a risk factor for ischemic stroke, affects the drug's pharmacokinetics. The objective of the present study was to investigate a possible relationship between smoking and responsiveness to clopidogrel in non-cardiogenic ischemic stroke patients.

METHODS

The study involved 209 non-cardiogenic ischemic stroke patients who were administered oral clopidogrel at a dosage of 75 mg/day for at least 1 week. Platelet aggregation in response to adenosine diphosphate (20 μM) was measured in each patient using the VerifyNow P2Y12 Assay. Platelet aggregation and the incidence of resistance to clopidogrel were compared between a smokers group (70 patients) and a non-smokers group (139 patients). Clopidogrel resistance was defined as a P2Y12 Reaction Units (PRU) value >230 and/or % inhibition <20%.

RESULTS

The mean PRU was 128.3±85.5 in the smokers group and 167.7±86.6 in the non-smokers group (p=0.002). The incidence of PRU >230 was 12.9% (9 patients) in the smokers group and 25.9% (36 patients) in the non-smokers group (p=0.033). The mean % inhibition was 48.6±30.7% in the smokers group and 36.9±27.6% in the non-smokers group (p=0.009). The incidence of patients with % inhibition <20% was 24.3% (17 patients) in the smokers group and 34.5% (48 patients) in the non-smokers group (p=0.155).

CONCLUSION

The incidence of clopidogrel resistance was lower in the non-cardiogenic ischemic stroke patients who were smokers, thus indicating that these patients' responsiveness to this drug may be enhanced.

Response to clopidogrel and its association with chronic kidney disease in noncardiogenic ischemic stroke patients

OBJECTIVE

Noncardiogenic ischemic stroke patients with chronic kidney disease (CKD) are known to have a greater rate of ischemic stroke recurrence than those without. Although clopidogrel is often used to prevent the recurrence of noncardiogenic ischemic stroke, the relationship between the response to clopidogrel and CKD is unclear. In the present study, the relationship between the response to clopidogrel and the presence of CKD was investigated in noncardiogenic ischemic stroke patients.

METHODS

A total of 129 noncardiogenic ischemic stroke patients receiving 75 mg/day of clopidogrel for ≥1 week were evaluated. The VerifyNow P2Y12 Assay was used to measure the level of platelet aggregation induced by 20 μM of adenosine diphosphate, and the degree of platelet aggregation and frequency of clopidogrel resistance were compared between 34 patients with CKD and 95 patients without CKD. Clopidogrel resistance was defined as a P2Y12 Reaction Units (PRU) value of >230 and/or % inhibition <20%.

RESULTS

The PRU value was 201.9±91.3 in the patients with CKD and 163.3±86.4 in the patients without CKD (p=0.035). The frequency of a PRU value of >230 was 44.1% (15 patients) among the patients with CKD and 17.9% (17 patients) among those without CKD (p=0.002). The percent inhibition was 29.9%±28.1% among the patients with CKD and 41.1%±28.0% among the patients without CKD (p=0.030). The frequency of % inhibition <20% was 47.1% (16 patients) among the patients with CKD and 26.3% (25 patients) among those without CKD (p=0.026).

CONCLUSION

The present study showed that noncardiogenic ischemic stroke patients with CKD have a greater frequency of clopidogrel resistance, thus suggesting that the response to clopidogrel is diminished in these patients.

Primary central nervous system cytotoxic T-cell lymphoma mimicking demyelinating disease

A 40-year-old man visited to our hospital due to progressive right hemiparesis. Magnetic resonance imaging demonstrated a heterogeneous contrast-enhanced lesion in the left basal ganglia with compression of the ventricles. A brain biopsy did not demonstrate central nervous system (CNS) lymphoma, although acute demyelination was observed. Despite the administration of steroids, the lesion increased in size, and the patient died three months after admission. An autopsy disclosed perivascular and parenchymal infiltration of lymphoma cells. An immunohistochemical analysis showed that the lesion was a cytotoxic T-cell lymphoma. This case indicates that the development of primary CNS lymphoma of this immunophenotype may be preceded by demyelination with subsequent rapid progression, thus requiring a careful evaluation and meticulous diagnosis.

Factors associated with onset-to-door time in patients with transient ischemic attack admitted to stroke centers

BACKGROUND AND PURPOSE

The aim of this study was to elucidate the factors associated with the time from symptom onset to arrival at a stroke center (onset-to-door time [ODT]) in patients with classically defined transient ischemic attack using data from a multicenter, retrospective study.

METHODS

The subjects were patients with transient ischemic attack admitted to 13 stroke centers in Japan within 7 days of onset between 2008 and 2009. A total of 464 patients registered (292 men, 68.5±13.2 years old), and 421 of them (268 men, 68.8±13.1 years old) were included in the analyses. ODT was classified into the following 5 categories: <3 hours, 3 to 6 hours, 7 to 12 hours, 13 to 24 hours, and >24 hours.

RESULTS

There were 233 patients (55.3%) who visited a stroke center within 3 hours of symptom onset. Multiple ordinal logistic regression analysis revealed that motor weakness, speech disturbance, and duration of symptoms >10 minutes were independently associated with a short ODT. Furthermore, a history of transient ischemic attack and hypertension and a referral from another medical facility were independently associated with a long ODT. Patients with a higher ABCD2 score were likely to arrive at a stroke center more quickly.

CONCLUSIONS

We identified several factors that were positively and negatively associated with the ODT in patients with transient ischemic attack.