Early neurological changes following endovascular therapy for acute stroke due to intracranial atherosclerotic disease

BACKGROUND

Endovascular therapy (EVT) reduces functional disability in patients with acute large vessel occlusion (LVO). However, the early neurological change after EVT may be limited in patients with intracranial atherosclerotic disease (ICAD).

METHODS

We analyzed the Japanese Registry of NeuroEndovascular Therapy (JR-NET) 4 which was a retrospective, nationwide, multicenter registry of patients with LVO between 2015 and 2019. We compared the early neurological change, efficacy and safety of EVT for acute LVO in ICAD and other etiologies. The primary outcome was NIHSS improvement ≥10 points, and secondary outcome were NIHSS worsening ≥4 points 7 days after EVT, effective reperfusion rate, 30-day functional outcomes, and safety outcomes.

RESULTS

Among the 6710 enrolled patients, 610 (9.1%) had ICAD. The ICAD group was younger (mean 72.0 vs. 75.8 years) and predominantly male (63.4% vs. 56.0%), had lower NIHSS scores before EVT (median 16 vs. 18), and underwent percutaneous transluminal angioplasty and stenting more frequently (43.0% vs. 4.4%, 12.3% vs. 4.4%). In the ICAD group, NIHSS improvement was significantly lower (adjusted odds ratio (aOR) [95% confidence interval (95%CI)] 0.52 [0.41-0.65]), NIHSS worsening was significantly higher (aOR [95%CI] 1.76 [1.31-2.34]), and effective reperfusion was significantly lower (aOR [95%CI] 0.47 [0.36-0.60]). Fewer patients with ICAD had modified Rankin scale 0-2 at 30 days (aOR [95%CI] 0.60 [0.47-0.77]). The risk of acute reocclusion was more prominent in the ICAD group (aOR [95%CI] 4.03 [1.98-8.21]).

CONCLUSIONS

Improvement in neurological severity after EVT was lower in patients with LVO and ICAD.

Technical and clinical outcomes of thrombectomy in patients with acute medium vessel occlusion and large vessel occlusion; sub-analyses of Japan Trevo registry

BACKGROUND

Little is known about endovascular therapy (EVT) for patients with medium vessel occlusion (MeVO) and more work is needed to establish its efficacy and to understand hemorrhagic complications.

METHODS

We analyzed the Japan Trevo Registry, which enrolled patients with acute stroke who underwent EVT using Trevo Retriever alone or in combination with an aspiration catheter. The primary outcome was effective reperfusion, and the secondary outcome was modified Rankin scale 0-2 at 90 days. Safety outcomes, including intracranial hemorrhage (ICH), were evaluated using a subgroup analyses focused on any ICH.

RESULTS

Among 1041 registered patients, 1025 patients were analyzed. 253 patients had MeVOs, and the majority (89.3%) had middle cerebral artery segment 2 (M2). The median National Institutes of Health Stroke Scale scores at admission were 15 and 19 for the MeVO and LVO groups (p < 0.0001). The primary outcome was 88.9% in MeVO vs. 91.8% in LVO group: adjusted odds ratio (aOR) [95% confidence interval (CI)] 0.60 [0.35-1.03], p = 0.07, and the secondary outcome was 43.2% vs. 42.2%, and the aOR [95%CI] was 0.70 [0.48-1.002], p = 0.051. However, the incidence of any ICH was more prominent in MeVO than in LVO group (35.7% vs. 28.8%, aOR [95%CI] 1.54 [1.10-2.15], p = 0.01). In subgroup analyses, the incidences of any ICH in MeVO group were generally higher than those in LVO group.

CONCLUSIONS

The effective reperfusion rate did not differ significantly between MeVO and LVO groups. Future development of devices and treatments for MeVO with fewer hemorrhagic complications is desirable.

Perioperative Antiplatelet Management in the Flow-Diverter Treatment for Unruptured Cerebral Aneurysms: A Single-Center, Retrospective Analysis

BACKGROUND

Although periprocedural antiplatelet therapy for the treatment of unruptured intracranial aneurysms (UIAs) using flow-diverter stents (FDSs) is necessary to avoid thromboembolic complications, a definite antiplatelet therapy has not been established. We aimed to evaluate the safety and efficacy of periprocedural antiplatelet management in UIA treatment with FDS.

METHODS

A single-center retrospective analysis of consecutive patients with UIAs treated with FDSs between September 2013 and January 2022 was conducted. Patients received dual antiplatelet therapy (DAPT) (aspirin and clopidogrel) for 14-day before and 3-6 months after FDS placement. Platelet aggregation was evaluated prior to treatment using light transmission aggregometry, which was classified into 3 grades; 1-3: promoted, 4-6: appropriate, and 7-9: non-responder, for adenosine diphosphate (ADP) and collagen. By this classification, the antiplatelet regimen was modified. Outcome included hemorrhagic and ischemic events.

RESULTS

193 patients with 200 UIAs underwent 213 FDSs placement. The median platelet aggregability grade before treatment was 5 for ADP and 4 for collagen. Antiplatelet therapy modification was performed in 62 patients (32.1%). The median postoperative DAPT duration was 94 days. Antiplatelet medicine-related hemorrhagic events occurred in 4 patients (2.1%) and ischemic events occurred in 6 patients (3.1%). These patients had no morbido-mortality.

CONCLUSIONS

Periprocedural antiplatelet management based on the value of platelet aggregability was relatively safe and effective for treating UIA with FDS.

Impact of atherosclerotic etiology on technical and clinical outcomes of mechanical thrombectomy with a stent retriever: subanalysis of the Japan Trevo Registry

BACKGROUND

The safety and effectiveness of stent retriever use for patients with acute large vessel occlusion (LVO) due to intracranial atherosclerotic disease (ICAD) is not well established. We investigated the differences in clinical outcomes in patients with and without ICAD.

METHODS

We analyzed the Japan Trevo Registry, a nationwide registry which enrolled patients with acute LVO who underwent endovascular therapy (EVT) using the Trevo retriever alone or in combination with an aspiration catheter. We compared the technical and clinical outcomes of EVT between the ICAD and No-ICAD groups. The primary outcome was effective reperfusion and the secondary outcome was modified Rankin scale (mRS) score 0-2 at 90 days. Safety outcomes were worsening of neurologic symptoms within 24 hours, any intracranial hemorrhage within 24 hours, vessel dissection/vessel perforation related to using the Trevo retriever and mortality at 90 days.

RESULTS

A total of 835 patients (45 in the ICAD group and 790 in the No-ICAD group) were analyzed. In the ICAD group, more men (68.9% vs 50.8%, P=0.02) and a lower median National Institutes of Health Stroke Scale score at admission (11 vs 18, P<0.0001) were observed. The primary outcome was significantly more common in the No-ICAD group (92.5%) than in the ICAD group (80.0%) (adjusted odds ratio (aOR) 0.21, 95% CI 0.09 to 0.50). The proportion of patients with mRS score 0-2 at 90 days was significantly lower in the ICAD group (44.4% vs 42.4%, aOR 0.49, 95% CI 0.23 to 1.00, P=0.0496). Other secondary and safety outcomes were not significantly different between the two groups.

CONCLUSIONS

Patients with LVO with ICAD had a lower rate of effective reperfusion than those with No-ICAD.

Prognostic Factors in Patients with Unruptured Vertebral and Basilar Fusiform Aneurysms Treated with Endovascular Procedures : A Single Center Retrospective Analysis

PURPOSE

Large vertebral and basilar fusiform aneurysms (VFA) are sometimes difficult to cure by endovascular treatment (EVT). We aimed to elucidate indicators of poor outcomes of EVT in patients with VFAs.

METHODS

Clinical data from 48 patients with 48 unruptured VFAs in the Hyogo Medical University were retrospectively analyzed. The primary outcome was defined as satisfactory aneurysm occlusion (SAO) according to Raymond-Roy grading scale. The secondary and safety outcomes were a modified Rankin scale (mRS) score of 0-2 at 90 days, retreatment, major stroke, and aneurysm-related death after EVT.

RESULTS

The EVT included stent-assisted coiling (n = 24; 50%), flow diverter (n = 19; 40%), and parent artery occlusion (n = 5; 10%). The SAO was less frequently observed in large or thrombosed VFAs at 12 months (64%, p = 0.021 and 62%, p = 0.014, respectively), especially when the aneurysms were both large and thrombosed (50%, p = 0.0030). Retreatment was more common in large aneurysms (29%, p = 0.034), thrombosed (32%, p = 0.011), and large thrombosed aneurysms (38%, p = 0.0036). Although the proportion of mRS 0-2 at 90 days and major stroke showed no significant differences, that of post-treatment rupture was significantly larger in large thrombosed VFAs (19%, p = 0.032). Aneurysm-related death occurred by aneurysm rupture and was more frequent in large thrombosed VFA (19%, p = 0.032). Multivariate analysis showed SAO at 12 months was less common (adjusted odds ratio, OR: 0.036, 95% confidence interval, CI 0.00091-0.57; p = 0.018), and retreatment was more common (adjusted OR 43, 95% CI 4.0-1381; p = 0.0012) in large thrombosed VFA.

CONCLUSION

The large thrombosed VFAs were associated with poor outcomes after EVT including flow diverter.

Japan Trevo Registry: Real-world Registry of Stent Retriever Alone or in Combined Therapy with Aspiration Catheter for Acute Ischemic Stroke in Japan

Endovascular therapy (EVT) for real-world patients after extended time frames is associated with concerns about its efficacy and safety. We conducted a prospective registry at 77 centers between November 2019 and October 2020. The registry criteria included patients treated with Trevo Retriever alone or in combined therapy with an aspiration catheter. The primary outcome was effective reperfusion (thrombolysis in cerebral infarction grade ≥ 2b), the secondary outcome was a modified Rankin scale 0-2 at 90 days, and the safety outcomes were worsening of neurologic symptoms within 24 h postoperatively, intracranial hemorrhage (ICH) within 24 h after EVT and mortality. We also exlpored the difference between patients whose last known well time (LKWT) to a puncture was less than 6 h (0-6 h) and those whose LKWT was 6 h or more but less than 24 h (6-24 h). Among the 1041 patients registered, 1025 patients were analyzed. The mean age was 76.9 years, and 53.6% of the participants were males. The 6-24 h group was 206/998 (20.6%), the median National Institute of Health Stroke Scale (NIHSS) score at admission was 18, and the median Alberta Stroke Program Early CT score was 8. Combined technique as the first pass was used on 817 (79.7%) patients. The primary outcome was 934 (91.1%). The secondary outcome was 433/1021 (42.4%). Symptomatic ICH, any ICH, and mortality were 10/1019 (1.0%), 311/1019 (30.5%), and 75 (7.3%). In the subanalysis, the 6-24 h group was lower in NIHSS (median;18 vs 16), and the secondary outcome was not significantly different in the <6 h group. Even after treatment time expansion, this result was comparable to other Trevo-based trials and nationwide registries.

Intravenous alteplase before endovascular therapy for acute large vessel occlusion with large ischemic core: subanalysis of a randomized clinical trial

BACKGROUND

The efficacy of endovascular therapy (EVT) in patients with large ischemic core has been reported, but it remains unclear whether IV alteplase (IVT) has beneficial effects in addition to EVT in such patients. We evaluated the efficacy and safety of EVT with or without IVT.

METHODS

The RESCUE-Japan LIMIT was an open-label, prospective, multicenter, randomized clinical trial to evaluate the efficacy and safety of EVT in stroke patients with large ischemic core, defined as Alberta Stroke Program Early CT Score (ASPECTS) 3-5. This subanalysis evaluated the differences in the effects of EVT with medical care (EVT group) compared with medical care alone (No-EVT group) between those who received IVT (IVT stratum) and those who did not (No-IVT stratum) before EVT.

RESULTS

Among 202 enrolled patients, 147 (73%) did not receive IVT. In the No-IVT stratum, the modified Rankin Scale (mRS) score of 0-3 at 90 days was significantly higher in the EVT group than in the No-EVT group (31.1% vs 12.3%, OR 3.21 (95% CI 1.37 to 7.53)). In the IVT stratum, the mRS score of 0-3 was 30.8% in the EVT group and 13.8% in the No-EVT group (OR 2.78 (95% CI 0.72 to 10.7)) (interaction p=0.77). The incidence of symptomatic intracranial hemorrhage was not different between the two groups in the No-IVT stratum (OR 1.20 (95% CI 0.35 to 4.12)), but it was significantly higher in the EVT group than in the No-EVT group in the IVT stratum (11.5% vs 0%, p=0.03).

CONCLUSIONS

There was no difference in efficacy of EVT with or without IVT, while IVT before EVT might increase symptomatic intracranial hemorrhage in patients with large ischemic core.

TRIAL REGISTRATION INFORMATION

NCT03702413.

Effect of edaravone on symptomatic intracranial hemorrhage in patients with acute large vessel occlusion on apixaban for non-valvular atrial fibrillation

BACKGROUND

Edaravone administration was associated with lower incidence of symptomatic intracranial hemorrhage (sICH) in patients with acute large vessel occlusion (LVO). However, its protective effect on sICH in patients with LVO who receive direct oral anticoagulants for non-valvular atrial fibrillation (NVAF) is uncertain.

OBJECTIVES

To explore the effect of edaravone administration on the incidence of sICH in patients with acute LVO receiving apixaban for NVAF.

METHODS

A Japanese multicenter registry of apixaban on clinical outcome of the patients with LVO or stenosis (ALVO study) included patients who were admitted within 24 h after stroke onset and were received apixaban within 14 days of stroke onset. Patients were divided into two groups according to edaravone administration (Edaravone and No-Edaravone groups). The incidence of sICH within one year and infarct growth before apixaban administration were compared between these groups.

RESULTS

Of the 686 enrolled patients, 622 were included and edaravone was administered to 407 (65.4%). The incidences of sICH in Edaravone and No-Edaravone groups were 1.3% and 5.0%, respectively (p = 0.01). The inverse probability of treatment-weighting (IPTW) hazard ratio (HR) (95% confidence interval [CI]) of Edaravone group for sICH within one year was 0.36 (0.15-0.80) compared to No-Edaravone group. The incidences of infarct growth in Edaravone and No-Edaravone groups were 35.3% and 42.0%, respectively (p = 0.13). IPTW HR (95% CIs) for infarct growth was 0.76 (0.60-0.97).

CONCLUSIONS

Edaravone administration was associated with a lower incidence of sICH in patients with LVO and NVAF who administrated apixaban.

Mode of Imaging Study and Endovascular Therapy for a Large Ischemic Core: Insights From the RESCUE-Japan LIMIT

BACKGROUND AND PURPOSE

Differences in measurement of the extent of acute ischemic stroke using the Alberta Stroke Program Early Computed Tomographic Score (ASPECTS) by non-contrast computed tomography (CT-ASPECTS stratum) and diffusion-weighted imaging (DWI-ASPECTS stratum) may impact the efficacy of endovascular therapy (EVT) in patients with a large ischemic core.

METHODS

The RESCUE-Japan LIMIT (Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism Japan-Large IscheMIc core Trial) was a multicenter, open-label, randomized clinical trial that evaluated the efficacy and safety of EVT in patients with ASPECTS of 3-5. CT-ASPECTS was prioritized when both CT-ASPECTS and DWI-ASPECTS were measured. The effects of EVT on the modified Rankin Scale (mRS) score at 90 days were assessed separately for each stratum.

RESULTS

Among 183 patients, 112 (EVT group, 53; No-EVT group, 59) were in the CT-ASPECTS stratum and 71 (EVT group, 40; No-EVT group, 31) in the DWI-ASPECTS stratum. The common odds ratio (OR) (95% confidence interval) of the EVT group for one scale shift of the mRS score toward 0 was 1.29 (0.65-2.54) compared to the No-EVT group in CT-ASPECTS stratum, and 6.15 (2.46-16.3) in DWI-ASPECTS stratum with significant interaction between treatment assignment and mode of imaging study (P=0.002). There were significant interactions in the improvement of the National Institutes of Health Stroke Scale score at 48 hours (CT-ASPECTS stratum: OR, 1.95; DWIASPECTS stratum: OR, 14.5; interaction P=0.035) and mortality at 90 days (CT-ASPECTS stratum: OR, 2.07; DWI-ASPECTS stratum: OR, 0.23; interaction P=0.008).

CONCLUSION

Patients with ASPECTS of 3-5 on MRI benefitted more from EVT than those with ASPECTS of 3-5 on CT.

Endovascular therapy for acute intracranial large vessel occlusion due to atherothrombosis: Multicenter historical registry

BACKGROUND

Atherothrombotic stroke-related large vessel occlusion (AT-LVO) is caused by two etiologies, the intracranial artery occlusion due to in situ occlusion (intracranial group) or due to embolism from cervical carotid occlusion or stenosis (tandem group). The prognosis and reocclusion rate of each etiology after endovascular therapy (EVT) is unclear.

METHODS

We conducted a historical multicenter registry study at 51 Japanese centers to compare the prognoses of AT-LVO between two etiologies. The primary outcome was the incidence of recurrent ischemic stroke or reocclusion of the treated vessels within 90 days after EVT. Each of the primary outcome means the incidence of recurrent ischemic stroke and reocclusion of the treated vessels within 90 days after EVT.

RESULTS

We analyzed 582 patients (338 in the intracranial group and 244 in the tandem group). Patients in the intracranial group were younger (mean 71.9 vs 74.5, p=0.003), more of them were female and fewer of them were current smokers than those in the tandem group. In the tandem group, the patients' National Institutes of Health Stroke Scale score on admission was higher (13 vs 15, p=0.006), onset to puncture time was shorter (299 [145-631] vs 232 [144-459] minutes, p=0.03) and Alberta Stroke Program Early CT Score (ASPECTS) was lower (8 [7-9] vs 8 [6-9], p=0.0002). The primary outcome was higher in the intracranial group (22.5% vs 8.2%, p<0.0001). However, any ICH and death were not significantly different in the two groups.

CONCLUSIONS

The incidence of recurrent ischemic stroke or reocclusion after EVT for AT-LVO was higher in the intracranial group.

Impact of anemia on major bleeding in patients taking oral anticoagulants for nonvalvular atrial fibrillation

BACKGROUND

Anemia is encountered in patients with nonvalvular atrial fibrillation (NVAF) on oral anticoagulants (OACs) but the prognostic impact was not well scrutinized in real-world settings.

METHODS

We conducted a historical multicenter registry of patients with NVAF taking OACs at 71 centers in Japan. Those with mechanical heart valves or a history of pulmonary thrombosis or deep venous thrombosis were excluded. Anemic patients were divided into three groups of hemoglobin (Hb) level: moderate/severe (Hb < 11.0 g/dL), mild (men: Hb of 11.0-12.9 g/dL; women: Hb of 11.0-11.9 g/dL), and no anemia. The endpoints included major bleeding, hemorrhagic stroke, ischemic events, ischemic stroke, and all-cause mortality.

RESULTS

Among 7558 consecutive patients (mean age, 73 years; men 67%) registered in February 2013 and followed until February 2017, 2100 (28%) patients had anemia. The anemic patients were older (moderate/severe: 79 years; mild: 77 years; no anemia: 71 years, p < .001), and HAS-BLED score was significantly higher in the anemic patients (p < .001). The cumulative incidences at 4 years of major bleeding in moderate/severe, mild, and no anemia group, were 14.9%, 10.7%, and 6.4%, respectively. The adjusted hazard ratios (HRs) (95% confidential intervals (CIs)) of major bleeding of moderate/severe and mild anemia group were 1.96 (1.49-2.58) and 1.48 (1.17-1.87) compared to no anemia group. The adjusted HRs (95% CIs) for ischemic events were 0.63 (0.39-0.99) and 1.03 (0.76-1.39).

CONCLUSIONS

The severity of anemia in the patients with NVAF on OACs was associated with major bleeding.

Number of Passes of Endovascular Therapy for Stroke With a Large Ischemic Core: Secondary Analysis of RESCUE-Japan LIMIT

BACKGROUND

The increased risk of intracranial hemorrhage with multiple passes in endovascular therapy (EVT) for large vessel occlusion with a large ischemic core is a concern. We explored the effect of the number of EVT passes on patients in a randomized clinical trial.

METHODS

This post hoc study was the secondary analysis of RESCUE-Japan LIMIT, which was a randomized clinical trial comparing EVT and medical treatment alone for large vessel occlusion with large ischemic core. We grouped patients according to the number of passes with successful reperfusion (modified Thrombolysis in Cerebral Infarction score, ≥2b) in 1, 2, and 3 to 7 passes and failed reperfusion (modified Thrombolysis in Cerebral Infarction score, 0-2a) after any pass in the EVT group, and these groups were compared with medical treatment group. The primary outcome was modified Rankin Scale score of 0 to 3 at 90 days. Secondary outcomes were improvement in National Institutes of Health Stroke Scale score of ≥8 at 48 hours, mortality at 90 days, symptomatic intracranial hemorrhage, and any intracranial hemorrhage within 48 hours.

RESULTS

The number of patients who received EVT with successful reperfusion after 1, 2, and 3 to 7 passes and failed reperfusion were 44, 23, 19, and 14, respectively, and 102 received medical treatment alone. The adjusted odds ratios (95% CIs) for the primary outcome relative to medical treatment were 5.52 (2.23-14.28) after 1 pass, 6.45 (2.22-19.30) after 2 passes, 1.03 (0.15-4.48) after 3 to 7 passes, and 1.17 (0.16-5.37) if reperfusion failed. The adjusted odds ratios (95% CIs) for any intracranial hemorrhage within 48 hours relative to medical treatment were 1.88 (0.90-3.93) after 1 pass, 5.14 (1.97-14.72) after 2 passes, 3.00 (1.09-8.58) after 3 to 7 passes, and 6.16 (1.87-24.27) if reperfusion failed.

CONCLUSIONS

The successful reperfusion within 2 passes was associated with better clinical outcomes.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03702413.

Abstract 1: The Very Core Limit Of Endovascular Therapy For Acute Stroke With A Large Ischemic Region

Background and Purpose: To assess the actual malignant core volume in endovascular therapy (EVT) eligible patients with large ischemic regions from the RESCUE-Japan LIMIT database.

Methods: RESCUE-Japan LIMIT was a multicenter, open-label, randomized clinical trial in large vessel occlusion patients with large ischemic region indicated by an ASPECTS valued from 3 to 5. We assessed the volumetrically measured core volume which identifies an unfavorable outcome (modified Rankin Scale; mRS 4-6 at 90 days) by receiver operating characteristic (ROC) analysis in the endovascular therapy (EVT) group. Predictive marginal probabilities were also assessed to identify the unfavorable outcome. Symptomatic intracranial hemorrhages and death within 90 days in the EVT group and the medical management (MM) group were compared. Clinical characteristics and radiological values were also compared.

Results: Of the 203 cases enrolled, 182 patients (92 in EVT group vs. 90 in MM group) had adequate core volume. The mean age was 75.6±10 years old and 46% of females in the EVT group and 77.0±10 years old and 42% of females in the MM group. Median core volume was 94 (IQR; 65.3-147.5) mL in EVT patients and 110 (IQR; 74.0-140.0) mL in those with MM group (P=0.84). ROC analysis identified a core volume of 120 mL as the unfavorable outcome (61/92) in the EVT group (51% sensitivity and 77% specificity, area under curve=0.65) and 99 mL in the MM group (77/91, 62% sensitivity and 54% specificity, area under curve=0.56). Predictive marginal probabilities indicated 132 mL as an overlay of the two groups for achieving the unfavorable functional outcome. Symptomatic intracranial hemorrhage was seen in 9.8% in the EVT group and 5.6% in the MM group (p=0.28), and death within 90 days was 17.4% in the EVT group and 23.3% in the MM group (p=0.32).

Conclusions: The current analysis demonstrates that a core threshold of approximately 130 mL is the upper limit for identifying large ischemic region stroke patients treated with EVT who are unlikely to suffer from unfavorable outcomes. EVT-eligible patients under this threshold may benefit from EVT.

Registration: URL: http://www.clinicaltrials.gov; Unique identifier: NCT03702413.

Statins Reduce Bleeding Risk in Patients Taking Oral Anticoagulants for Nonvalvular Atrial Fibrillation: A Retrospective Registry Study

BACKGROUND

The effects of statins in patients with non-valvular atrial fibrillation (NVAF) taking oral anticoagulants (OACs) are not well-studied. This study was a historical multicenter registry of patients with NVAF taking OACs in Japan.

METHODS

We excluded those patients with mechanical heart valves or a history of pulmonary or deep vein thrombosis. Overall, 7826 patients were registered on 26 February 2013 and followed until 25 February 2017. We compared those with versus without statin treatment (statin vs. no-statin groups) for the primary outcome of major bleeding and secondary outcomes of all-cause mortality, ischemic events, hemorrhagic stroke, and ischemic stroke.

RESULTS

Statins were administered in 2599 (33%) patients. The statin group was more likely to have paroxysmal AF (37% vs. 33%; p = 0.0003), hypertension (84% vs. 76%; p < 0.0001), diabetes mellitus (41% vs. 27%; p < 0.0001), and dyslipidemia (91% vs. 30%; p < 0.0001) than the no-statin group. The cumulative incidence of major bleeding was 6.9% and 8.1% (p = 0.06). The adjusted hazard ratio [HR] (95% confidence interval [CI]) of the statin group for major bleeding was 0.77 (0.63-0.94) compared with the no-statin group. The adjusted HR (95% CI) for all-cause mortality, ischemic events, hemorrhagic stroke, and ischemic stroke were 0.58 (0.47-0.71), 0.77 (0.59-0.999), 0.85 (0.48-1.50), and 0.79 (0.60-1.05), respectively.

CONCLUSIONS

Statins significantly reduced the risk of major bleeding, all-cause mortality, and ischemic events in patients with NVAF taking OACs. Their additive benefits should be considered in routine practice and thus be further researched.

Association Between Alberta Stroke Program Early Computed Tomography Score and Efficacy and Safety Outcomes With Endovascular Therapy in Patients With Stroke From Large-Vessel Occlusion: A Secondary Analysis of the Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism-Japan Large Ischemic Core Trial (RESCUE-Japan LIMIT)

Importance

Endovascular therapy (EVT) has been found to reduce functional disability in patients with acute stroke due to large-vessel occlusion. However, the extent of the ischemic region, measured using Alberta Stroke Program Early Computed Tomography Scores, may limit the efficacy of EVT.

Objective

To compare the efficacy and safety of EVT according to ASPECTS 3 or less vs 4 to 5.

Design, Setting, and Participants

The Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism-Japan Large Ischemic Core Trial (RESCUE-Japan LIMIT) was an open-label randomized clinical trial conducted from November 2018 to December 2021 at 45 stroke centers across Japan. The trial enrolled adult patients with acute ischemic stroke with a large ischemic region, defined as ASPECTS 3 to 5 primarily determined by magnetic resonance imaging, with occlusion site at the internal carotid artery or middle cerebral artery segment 1. Among 203 enrolled patients, 1 withdrew consent and 202 were included in the original trial and secondary analysis. This secondary analysis was conducted in April 2022.

Interventions

Patients were randomly assigned to EVT with medical therapy or medical therapy alone.

Main Outcomes and Measures

Modified Rankin Scale (mRS) score at 90 days and symptomatic and any intracranial hemorrhage within 48 hours.

Results

Among 202 patients, 106 (52%) had ASPECTS 3 or less (mean [SD] age, 76.7 [9.6] years; 54 female individuals [50.9%]) and 96 had ASPECTS 4 to 5 (mean [SD] age, 75.6 [10.6] years; 36 female individuals [37.5%]). Of patients with ASPECTS 3 or less, 12 (21.4%) in the EVT group and 9 (18.0%) in the no EVT group had an mRS score of 0 to 3 (odds ratio [OR], 1.24; 95% CI, 0.47-3.26). Of patients with ASPECTS 4 to 5, 19 patients (43.2%) in the EVT group and 4 (7.7%) in the no EVT group had an mRS score of 0 to 3 at 90 days (OR, 9.12; 95% CI, 2.80-29.70; interaction P = .01). The ordinal shift across the range of mRS scores toward a better outcome was not significant in those with ASPECTS or 3 or less (common OR, 1.56; 95% CI, 0.79-3.10) but was significant in those with ASPECTS 4 to 5 (common OR, 4.48; 95% CI, 2.07-9.71; interaction P = .046). The risk of intracranial hemorrhage was significantly increased in patients with ASPECTS 3 or less when EVT was conducted (OR, 4.14; 95% CI, 1.84-9.32) and nonsignificantly increased in those with ASPECTS 4 to 5 (OR, 2.05; 95% CI, 0.89-4.73; interaction P = .24).

Conclusions and Relevance

In this study, EVT was associated with improved 90-day functional outcomes in patients with acute large vessel occlusive stroke and ASPECTS was 4 to 5 but not in those with ASPECTS 3 or less.

Trial Registration

ClinicalTrials.gov Identifier: NCT03702413.

Association between Acid-Suppressive Drugs and Clinical Outcomes in Patients with Nonvalvular Atrial Fibrillation

Purpose

Acid-suppressive drugs (ASDs) are often prescribed for patients with nonvalvular atrial fibrillation (NVAF) taking oral anticoagulants (OACs). However, the risk-benefit balance of ASDs prescription for patients with NVAF taking OACs is still unclear. This study aimed to assess the association between ASDs and clinical outcomes in patients taking OACs for NVAF.

Methods

This study is a subanalysis of an historical registry study from 71 centers in Japan. We included patients taking vitamin K antagonists for NVAF and excluded those with mechanical heart valves or a history of pulmonary thrombosis or deep vein thrombosis. We registered consecutive patients in February 2013 and followed them up until February 2017. The primary outcomes were ischemic events, major bleedings, and all-cause mortality. Ischemic stroke, acute myocardial infarction, and hemorrhagic stroke comprised the secondary outcomes.

Results

We included 7826 patients with a mean age of 73 years, 5274 (67%) of whom were males. The adjusted hazard ratios (95% confidence intervals) for ischemic events, major bleedings, and all-cause mortality in the ASD group compared with the no-ASD group were 0.998 (0.78–1.27), 0.98 (0.81–1.18), and 1.22 (1.02–1.47), respectively, while those for ischemic stroke, acute myocardial infarction, and hemorrhagic stroke were 0.96 (0.74–1.24), 0.82 (0.36–1.88), and 1.17 (0.69–1.99), respectively.

Conclusions

ASDs were significantly associated with all-cause mortality in patients with NVAF taking OACs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40268-022-00392-5.

Effect of current smoking on ischemic events in patients with atrial fibrillation taking vitamin K antagonist

Purpose

We investigated the association between current smoking and clinical outcomes in patients with atrial fibrillation (AF) prescribed vitamin K antagonist (VKA).

Methods

We conducted a retrospective study at 71 centers in Japan. The inclusion criterion was taking a VKA for AF. Exclusion criteria were mechanical heart valves or history of pulmonary thrombosis or deep vein thrombosis. Consecutive patients were registered in February 2013 and followed until February 2017. The primary outcomes included ischemic events and major bleedings. The secondary outcomes were ischemic stroke, hemorrhagic stroke, and all-cause mortality.

Results

A total of 7826 patients were included, with a mean age of 73 years; 5274 (67%) were men. The adjusted hazard ratios (HRs; 95% confidence intervals [CIs]) of current smokers relative to non-current smokers for ischemic events and major bleedings were 1.64 (1.05-2.57) and 1.09 (0.72-1.65), respectively. The adjusted HRs (95% CIs) of current smokers relative to non-current smokers for ischemic stroke, hemorrhagic stroke, and all-cause mortality were 1.65 (1.03-2.64), 0.52 (0.12-2.15), and 1.26 (0.83-1.92), respectively.

Conclusions

There were significant associations between current smoking and ischemic events or ischemic stroke in patients with AF on VKA.

Endovascular Therapy for Acute Stroke with a Large Ischemic Region

BACKGROUND

Endovascular therapy for acute ischemic stroke is generally avoided when the infarction is large, but the effect of endovascular therapy with medical care as compared with medical care alone for large strokes has not been well studied.

METHODS

We conducted a multicenter, open-label, randomized clinical trial in Japan involving patients with occlusion of large cerebral vessels and sizable strokes on imaging, as indicated by an Alberta Stroke Program Early Computed Tomographic Score (ASPECTS) value of 3 to 5 (on a scale from 0 to 10, with lower values indicating larger infarction). Patients were randomly assigned in a 1:1 ratio to receive endovascular therapy with medical care or medical care alone within 6 hours after they were last known to be well or within 24 hours if there was no early change on fluid-attenuated inversion recovery images. Alteplase (0.6 mg per kilogram of body weight) was used when appropriate in both groups. The primary outcome was a modified Rankin scale score of 0 to 3 (on a scale from 0 to 6, with higher scores indicating greater disability) at 90 days. Secondary outcomes included a shift across the range of modified Rankin scale scores toward a better outcome at 90 days and an improvement of at least 8 points in the National Institutes of Health Stroke Scale (NIHSS) score (range, 0 to 42, with higher scores indicating greater deficit) at 48 hours.

RESULTS

A total of 203 patients underwent randomization; 101 patients were assigned to the endovascular-therapy group and 102 to the medical-care group. Approximately 27% of patients in each group received alteplase. The percentage of patients with a modified Rankin scale score of 0 to 3 at 90 days was 31.0% in the endovascular-therapy group and 12.7% in the medical-care group (relative risk, 2.43; 95% confidence interval [CI], 1.35 to 4.37; P = 0.002). The ordinal shift across the range of modified Rankin scale scores generally favored endovascular therapy. An improvement of at least 8 points on the NIHSS score at 48 hours was observed in 31.0% of the patients in the endovascular-therapy group and 8.8% of those in the medical-care group (relative risk, 3.51; 95% CI, 1.76 to 7.00), and any intracranial hemorrhage occurred in 58.0% and 31.4%, respectively (P<0.001).

CONCLUSIONS

In a trial conducted in Japan, patients with large cerebral infarctions had better functional outcomes with endovascular therapy than with medical care alone but had more intracranial hemorrhages. (Funded by Mihara Cerebrovascular Disorder Research Promotion Fund and the Japanese Society for Neuroendovascular Therapy; RESCUE-Japan LIMIT ClinicalTrials.gov number, NCT03702413.).

Experience and awareness of research integrity among Japanese physicians: a nationwide cross-sectional study

OBJECTIVES

To explore the awareness and practice of clinical research integrity among Japanese physicians.

DESIGN

A nationwide cross-sectional study conducted in March 2020.

SETTING

All hospitals in Japan.

PARTICIPANTS

Physicians aged <65 years who work at hospitals participated in clinical research over the past 5 years. The sample was stratified according to geographical location and subspecialty, and 1100 physicians were proportionally selected.

PRIMARY AND SECONDARY OUTCOME MEASURES

Knowledge and awareness of research integrity.

RESULTS

Among the 1100 participants, 587 (53%) had the experience of being the first author, 299 (27%) had been co-authors only and 214 (19%) had no authorship. A total of 1021 (93%) had experienced learning research integrity, and 555 (54%) became aware of research integrity. The experience of learning about research integrity was highest among those with first authorship (95%) and lowest among those without authorship (89%) (p=0.003). The majority of participants learnt about research integrity for passive reasons such as it being 'required by the institution' (57%) or it being 'required to obtain approval of institutional review board (IRB)' (30%). Potentially inappropriate research behaviours were observed in participants, with 11% indulging in copying and pasting for writing the paper, 11% for gifted authorship and 5.8% for the omission of IRB approval. Factors significantly associated with copying and pasting were being below 40 years old (OR: 1.84; 95% CI: 1.05 to 3.26), being the first presenter (OR: 1.64; 95% CI: 1.05 to 2.57) or having passive reasons for learning research integrity (OR: 2.96; 95% CI: 1.57 to 5.59). Furthermore, gifted authorship was significantly associated with being a co-author only (OR: 1.84; 95% CI: 1.18 to 2.87) and having passive reasons for learning about research integrity (OR: 1.79; 95% CI: 1.03 to 3.12).

CONCLUSIONS

Most physicians conducting clinical research have learnt about research integrity, but potentially inappropriate research behaviours are associated with passive reasons for learning.

Effect of prior antiplatelet therapy on large vessel occlusion in patients with non-valvular atrial fibrillation newly initiated on apixaban

INTRODUCTION

We evaluated the effect of prior antiplatelet therapy on large vessel occlusion (LVO) in patients with non-valvular atrial fibrillation (NVAF) newly initiated on apixaban.

METHODS

Patients with acute LVO with acute stroke due to NVAF or stenosis with NVAF started on apixaban within 14 days of onset were enrolled. We compared incidence of major bleeding, cerebral hemorrhage, ischemic events, cerebral infarction, and all-cause mortality between patients with and without prior antiplatelet therapy for acute LVO. We also compared these events between patients who continued antiplatelet therapy after onset (continued group) and those who discontinued it (discontinued group). Hazard ratios were estimated after adjusting for confounders; interaction was evaluated considering intravenous thrombolysis (IVT) or endovascular treatment (EVT) according to major bleeding.

RESULTS

The study comprised 686 eligible patients (excluded [n = 194]; enrolled [n = 492]). The antiplatelet group consisted of older patients (mean: 79 vs. 76 years; p = 0.006) and had a higher cumulative incidence of major bleeding (7.3% vs. 2.9%, p = 0.003). The incidence of ischemic events and all-cause mortality was similar between the groups. Among the 109 patients in the antiplatelet group, the cumulative incidence of major bleeding, ischemic events, and all-cause mortality was comparable between continued group (n = 26) and discontinued group (n = 83). There were no significant differences between groups with and without IVT/EVT. However, major bleeding occured more frequently in the antiplatelet group without IVT.

CONCLUSION

Prior antiplatelet therapy for LVO in patients with NVAF newly initiated on apixaban was associated with major bleeding, which was more frequent in the antiplatelet group without IVT.

Effect of concomitant antiplatelet therapy on ischemic and hemorrhagic events in patients taking oral anticoagulants for nonvalvular atrial fibrillation in daily clinical practice

PURPOSE

Antiplatelet therapy (APT) is challenging in patients taking oral anticoagulants (OACs) for nonvalvular atrial fibrillation (NVAF) with concomitant atherosclerotic diseases. We scrutinized the generalizability of recent randomized clinical trials showing OAC use alone was superior to OAC plus antiplatelet use in patients with NVAF and coronary artery diseases (CAD).

METHODS

We conducted a historical multicenter registry at 71 centers in Japan. The inclusion criterion was taking OACs for NVAF. The exclusion criteria were mechanical heart valves or history of pulmonary thrombosis or deep vein thrombosis. Consecutive patients (N = 7826) were registered in February 2013 and were followed until February 2017. The co-primary endpoints were ischemic events and major bleedings. Secondary endpoints were ischemic stroke, hemorrhagic stroke, and all-cause mortality.

RESULTS

The mean patient age was 73 years; 67% were men. Antiplatelets were administered in 25% of patients and 27% had history of CAD. Cumulative incidences of ischemic events and major bleedings at 4 years were 5.9% and 9.6% in the APT group and 5.3% and 7.0% in the No-APT group, respectively. The adjusted hazard ratios (HRs) (95% confidence intervals [CIs]) of the APT group for ischemic events and major bleedings were 1.12 (0.84-1.49) and 1.26 (1.01-1.57), respectively. The adjusted HRs (95% CIs) for ischemic stroke, hemorrhagic stroke, and all-cause mortality were 1.16 (0.86-1.57), and 1.31 (0.70-2.48), and 1.02 (0.82-1.26), respectively.

CONCLUSIONS

APT in patients taking OACs for NVAF did not prevent ischemic events but significantly increased major bleedings in the real-world setting.

ASPECTS-Region-Dependent Functional Outcomes after Endovascular Therapy in Patients with Cardioembolic Stroke

OBJECTIVES

Cardioembolic stroke has a poor prognosis. We evaluated the region-dependent efficacy of endovascular therapy (EVT) based on diffusion-weighted imaging-Alberta Stroke Program Early CT Score (DWI-ASPECTS).

METHODS

This post-hoc analysis of the RELAXED study, which investigated the optimal timing of rivaroxaban to prevent nonvalvular atrial fibrillation (NVAF) recurrence in patients with acute ischemic stroke (AIS), included NVAF patients admitted with AIS or transient ischemic attack in the middle cerebral artery (MCA), with internal carotid artery (ICA), M1, or M2-MCA occlusion. Relationships between DWI-ASPECTS region and functional outcome (modified Rankin Scale [mRS]), mortality, recurrence, and hemorrhagic stroke were compared between patients with and without EVT, and adjusted odds ratios for age, pre-stroke mRS, National Institutes of Health Stroke Scale (NIHSS), ICA occlusion, infarct size, recombinant tissue plasminogen activator (rt-PA) use, and onset-to-hospitalization time were estimated.

RESULTS

EVT patients had significantly lower hemoglobin levels, higher median NIHSS scores, more lentiform nucleus infarcts, ICA or M1-MCA occlusions, treatment with rt-PA, and fewer M3, M5, or M6 infarcts and M2-MCA occlusions than no-EVT patients. EVT patients had shorter onset-to-hospitalization times and more frequent favorable functional outcomes (p=0.007). Mortality, recurrent ischemic stroke, and hemorrhagic infarction were similar in both groups. EVT was associated with significantly better functional outcomes among patients with insular ribbon (p=0.043) and M3 (p=0.0008) infarcts. M3 patients had significantly fewer rt-PA and EVT, and longer onset-to-hospitalization times.

CONCLUSIONS

An occlusion in the insular ribbon or M3 region was associated with favorable functional outcomes in patients treated with EVT after cardioembolic stroke.

Sex Differences in Management and Outcomes of Cardioembolic Stroke: Post HOC Analyses of the RELAXED Study

INTRODUCTION

Experimental models have clearly demonstrated sex differences in the pathophysiology of stroke and prognosis, however clinical evidence remains elusive. In this study, we examined sex differences as a post hoc analysis of RELAXED (Recurrent Embolism Lessened by rivaroxaban, an anti-X agent, of Early Dosing for acute IS and TIA with atrial fibrillation) Study.

METHODS

We stratified study participants by sex and compared baseline and clinical characteristics as well as clinical outcomes. The primary outcome measure was a good outcome defined as a modified Rankin Scale score of 0-2 at 90 days after stroke. Secondary outcomes were mortality at 90 days, intracranial hemorrhage within 90 days, and recurrence of stroke or transient ischemic attack within 90 days. We constructed a logistic regression model to estimate the adjusted odds ratio of female patients compared with male patients for the primary and secondary outcomes.

RESULTS

Of 1303 patients, most were male (57.7%) with a mean age of 74.5 years. Female patients were older with a mean age of 80.6 ± 8.9 years and had significantly less frequent anticoagulation therapy before onset of stroke and more severe NIHSS scores. Good outcome was observed in 51.2% and 63.3% of the females and males (p < 0.0001). The adjusted odds ratio of a good outcome in females was 1.12 (95% confidence interval, 0.44-2.87) (p = 0.81). There were no sex differences in secondary outcomes.

CONCLUSION

Adjusted regression analysis found no sex difference in the treatment outcomes at 90 days after stroke with non-valvular atrial fibrillation.

[Important Points for Patient Positioning and Head Fixation in Cerebral Aneurysm Surgery]

Patient positioning and head fixation are two of the most important aspects of cerebral aneurysm surgery. These procedures require an accurate understanding of the anatomy of the scalp and skull and of the process for approaching aneurysms. We describe the basics of this procedure in frontotemporal craniotomy, which is most frequently used in cerebral aneurysm surgery, with a focus on head fixation using the MAYFIELD three-pin skull clamp(Integra LifeSciences). The insertion sites of the head pins should be avoided in areas with thin bone, such as the frontal sinus and temporal squama, and just above the arteries of the scalp and venous sinuses. The position of the head should be determined based on three factors: rotation, vertex up or down, and tilt. The head should be elevated to reduce intracranial pressure, and cervical hyperflexion should be avoided to prevent increased venous pressure.

Simplified Prehospital Prediction Rule to Estimate the Likelihood of 4 Types of Stroke: The 7-Item Japan Urgent Stroke Triage (JUST-7) Score

OBJECTIVE

Prehospital prediction models to estimate the likelihood of several types of stroke (large vessel occlusion [LVO], intracranial hemorrhage [ICH], and subarachnoid hemorrhage [SAH], and other types of stroke) should be useful to transfer those with suspected stroke to appropriate facilities. We recently reported Japan Urgent Stroke Triage (JUST) score with 21 items had excellent predictive abilities, and we further tried to simplify the score with parsimonious items and comparable predictive abilities.

METHODS

We conducted historical and prospective multicenter cohort studies at 8 centers from June 2015 to March 2018. We developed the prediction rules with select variables from JUST score for LVO, ICH, SAH and other types of stroke in 2236 patients with suspected stroke in historical derivation cohort. We validated the developed prediction rules in 964 patients in prospective validation cohort.

RESULTS

There were 1150 stroke, including 235 LVO, 352 ICH, 107 SAH and 456 other types of stroke in the derivation cohort. We developed the scores with 7 items (high blood pressure, arrhythmia, conjugate deviation, headache, dysarthria, disturbance of consciousness, paralysis of upper limbs) and the developed scores had area under the receiver-operating curve (AUC) of 0.84 for any type of stroke, 0.89 for LVO, 0.79 for ICH, and 0.90 for SAH in the derivation cohort. There were 490 stroke, including 102 LVO, 138 ICH, 28 SAH and 222 other types of stroke in the validation cohort. The scores well discriminated these strokes in the validation cohort (AUC of 0.76 for any type of stroke; 0.81 for LVO, 0.73 for ICH, and 0.85 for SAH).

CONCLUSIONS

The simplified 7-item JUST (JUST-7) score had good predictive ability and can help healthcare providers to estimate the likelihood of different types of stroke and decide the referral hospital.

Diffusion-Weighted Imaging-Fluid-Attenuated Inversion Recovery Mismatch Is Associated with 90-Day Functional Outcomes in Patients Undergoing Mechanical Thrombectomy

BACKGROUND AND PURPOSE

Diffusion-weighted imaging-fluid-attenuated inversion recovery (DWI-FLAIR) mismatch is an early sign of acute ischemic stroke. DWI-FLAIR mismatch was reported to be valuable to select patients with unknown onset stroke who are eligible to receive intravenous thrombolysis (IVT), but its utility is less studied in patients undergoing mechanical thrombectomy (MT) for acute large vessel occlusion (LVO). We thus investigated the functional outcomes at 90 days between patients with DWI-FLAIR mismatch and those with match who underwent MT for LVO.

METHODS

We conducted a historical cohort study in consecutive patients who were evaluated by magnetic resonance imaging for suspected stroke at a single center. We enrolled patients with occlusion of internal carotid artery or horizontal or vertical segment of middle cerebral artery who underwent MT within 24 h after they were last known to be well. DWI-FLAIR mismatch was defined when a visible acute ischemic lesion was present on DWI without traceable parenchymal hyperintensity on FLAIR. Image analysis was done by 2 stroke neurologists independently. We estimated the adjusted odds ratio (OR) of DWI-FLAIR mismatch relative to DWI-FLAIR match for moderate outcome defined as modified Rankin Scale (mRS) 0-3, favorable outcome defined as mRS 0-2 and mortality at 90 days after the onset, and symptomatic intracranial hemorrhage (sICH) within 72 h after the onset.

RESULTS

Of the 380 patients who received MT, 202 were included. Patients with DWI-FLAIR mismatch (146 [72%]) had significantly higher baseline National Institutes of Health Stroke Scale (median 16 vs. 13, p = 0.01), more transferred-in (78 vs. 63%, p = 0.02), more IVT (45 vs. 18%, p = 0.0003), more cardioembolism (69 vs. 54%, p = 0.03), and shorter onset-to-hospital door times (median 175 vs. 371 min, p < 0.0001) than patients with DWI-FLAIR match. Patients with DWI-FLAIR mismatch had more moderate outcome than those with DWI-FLAIR match (61 vs. 52%, p = 0.24), and the adjusted OR was 3.12 (95% confidence interval [CI]: 1.35-7.19, p = 0.008). sICH within 72 h was less frequent in the DWI-FLAIR mismatch group (10 vs. 20%, p = 0.06), with an adjusted OR of 0.36 (95% CI: 0.13-0.97, p = 0.044). The adjusted ORs for favorable outcome and mortality were 0.87 (95% CI: 0.39-1.94, p = 0.73) and 0.63 (95% CI: 0.20-2.05, p = 0.44), respectively.

CONCLUSIONS

DWI-FLAIR mismatch was associated with more moderate outcome and less sICH in the adjusted analysis in patients receiving MT for acute LVO. DWI-FLAIR mismatch could be useful to select patients with unknown onset stroke who are eligible to receive MT for acute LVO.

Abstract WP293: Simplified Prehospital Prediction Models to Estimate the Likelihood of 4 Types of Stroke: 7-Item Japan Urgent Stroke Triage (Just-7) Score

Background and Purpose: Prehospital prediction models to estimate the likelihood of several types of stroke (large vessel occlusion [LVO], intracranial hemorrhage [ICH], and subarachnoid hemorrhage [SAH], and other strokes) should be useful to transfer those with suspected stroke to appropriate facilities. Japan Urgent Stroke Triage score with 21 items had excellent predictive abilities, but we tried to simplify the score with parsimonious items and comparable predictive abilities.

Methods: We conducted historical and prospective multicenter cohort studies from June 2015 to July 2017. We developed the prediction rule with select variables from JUST score for LVO, ICH, SAH and other strokes using historical cohort study with 2236 patients and validated the developed score using prospective cohort study with 964 patients. We used multivariable logistic regression models to develop the prediction models using the same variables for each stroke type.

Result: In the historical cohort, there were 1150 stroke, including 235 LVO, 352 ICH, 107 SAH and 456 other stroke. We developed the score with 7 items (high blood pressure, arrhythmia, conjugate deviation, headache, dysarthria, disturbance of consciousness, paralysis of upper limbs) which showed area under the receiver operating curve (AUC) of 0.84 for any type of stroke, 0.89 for LVO, 0.79 for ICH, and 0.90 for SAH in the historical cohort. The score was validated with good predictive ability in the prospective cohort (AUC of 0.76 for any type of stroke; 0.81 for LVO, 0.73 for ICH, and 0.85 for SAH).

Conclusions: The simplified 7-item JUST (JUST-7) score had good predictive ability and can help paramedics or primary care physicians to estimate the likelihood of different type of stroke and decide the referral hospital.

Abstract WMP115: Hemorrhagic and Ischemic Stroke in Patients on Oral Anticoagulants for Nonvalvular Atrial Fibrillation With and Without Antiplatelet Therapy

Introduction: Antiplatelet (APT) therapy is challenging in patients on oral anticoagulants (OACs) for nonvalvular atrial fibrillation (NVAF) who have coronary artery diseases (CAD). Analyzing large scale registry of consecutive patients with NVAF should provide further guide for the safety and efficacy of combination therapy.

Methods: We conducted historical multicenter registry at 71 centers in Japan between March 2017 and March 2018. The eligibility criteria were patients on OACs for NVAF on February 2013. There were no exclusion criteria and consecutive patients who met the eligibility criteria were registered. All patients were followed until March 2017. Co-primary endpoints were ischemic strokes including transient ischemic attack and hemorrhagic stroke including subarachnoid hemorrhage. The secondary endpoints were all-cause mortality, ischemic events (acute coronary syndrome, ischemic strokes, or systemic embolism), and major bleedings defined by ISTH and TIMI criteria. We estimated HRs of OACs and APT combination relative to OACs alone by Cox proportional hazard model adjusting for clinically relevant confounders.

Results: Median age was 74 (range 20-101) years of 7826 registered patients. Sustained NVAF accounted for 49% and 73% of patients had history of CAD. Cumulative incidences of ischemic stroke and hemorrhagic stroke at 4 years were 3.8% and 0.91% in No-APT group while 5.3% and 1.2% in APT group, respectively (Figure). Adjusted HRs (95%CI) of APT group for ischemic stroke and hemorrhagic stroke were 1.03 (0.76-1.40) and 1.27 (0.67-2.4), respectively. Adjusted HRs (95%CI) for all-cause mortality, ischemic events, and major bleedings were 0.98 (0.79-1.23), 0.98 (0.74-1.32), and 1.25 (1.00-1.57), respectively.

Conclusions: Adding APT in patients on AOC for NVAF did not decrease ischemic strokes and not increase hemorrhagic strokes. Because combination therapy might increase the risk of major bleedings, OAC alone should be prioritized.

Abstract TP69: Association Between DWI-FLAIR Mismatch and Functional Outcomes in Patients Undergoing Mechanical Thrombectomy

Background and Purpose: Diffusion weighted imaging-fluid attenuated inversion recovery (DWI-FLAIR) mismatch was well recognized as an early sign of acute ischemic stroke lesions. In the era of mechanical thrombectomy (MT), DWI-FLAIR mismatch could be a good marker for candidates of MT. We thus investigated the association between DWI-FLAIR mismatch and functional outcomes in patients who received MT for acute large vessel occlusion (LVO).

Methods: We conducted historical cohort study in consecutive patients who were evaluated by MRI for suspected stroke at single stroke center. We enrolled patients with occlusion of the ICA or M1 or M2 segment of MCA who were underwent MT within 24 hours after the last known to be well. FLAIR negative was defined when a visible acute ischemic lesion was present on DWI without traceable parenchymal hyperintensity on FLAIR. We estimated the adjusted OR of FLAIR negative for moderate outcome defined as mRS 0-3 at 90 days after onset. We also estimated the adjusted OR for symptomatic intracranial hemorrhage within 72 hours and mortality at 90 days.

Results: Among 380 patients who received MT for acute LVO, 202 patients were included in this study. Patients with FLAIR negative was 146 (72%), and the rest were FLAIR positive. Patients with FLAIR negative had significantly higher baseline NIHSS (median 16 vs 13, p=0.01), more transferred-in (78% vs 63%, p=0.02), more intravenous thrombolysis (IVT) (45% vs 18%, P=0.0003), more cardioembolism (69% vs 54%, p=0.03), and shorter times from the onset to hospital door (median 175 vs 371 minutes, p<0.0001). Patients with FLAIR negative had more moderate outcome than the counterparts (61% vs 52%, p=0.24). The adjusted OR of FLAIR negative compared to positive was 2.97 (95%CI, 1.33-6.60, p=0.008). Symptomatic intracranial hemorrhage within 72 hours was less frequent in the FLAIR negative group (10% vs 20%, p=0.06), with an adjusted OR of 0.34 (95%CI, 0.13-0.87, p=0.02).

Conclusions: DWI-FLAIR mismatch was associated with better functional outcome in patients received MT for acute LVO at 90 days. DWI-FLAIR mismatch should be a good marker for the candidate of MT for acute LVO. Future randomized trial to evaluate the effectiveness of MRI-based MT using DWI-FLAIR mismatch should be considered.

Posterior Inferior Cerebellar Artery Thrombosed Aneurysm Associated with Persistent Primitive Hypoglossal Artery Successfully Treated with Condylar Fossa Approach

A 68-year-old woman presented with generalized seizure due to the left internal carotid artery (ICA) aneurysmal compression of the ipsilateral medial temporal lobe. Computed tomography angiography (CTA) revealed multiple aneurysms of the right persistent primitive hypoglossal artery (PPHA), the right ICA, and the right anterior cerebral artery (ACA). The right PPHA originated from the ICA at the level of the C1 and C2 vertebral bodies and passed through the hypoglossal canal (HC). The PPHA aneurysm was large and thrombosed, which was located at the bifurcation of the right PPHA and the right posterior inferior cerebellar artery (PICA), projecting medially to compress the medulla oblongata. Since this patient had no neurological deficits, sequential imaging studies were performed to follow this lesion, which showed gradual growth of the PPHA aneurysm with further compression of the brain stem. Although the patient remained neurologically intact, considering the growing tendency clipping of the aneurysm was performed. Drilling of the condylar fossa was necessary to expose the proximal portion of the PPHA inside the HC. The key of this surgery was the preoperative imaging studies to fully understand the anatomical structures. The PPHA was fully exposed from the dura to the corner its turning inferiorly without damaging the occipital condylar facet. Utilizing this technique, the neck ligation of the aneurysm was safely achieved without any surgical complications.

Surgical Microanatomy of the Posterior Condylar Emissary Vein and its Anatomical Variations for the Transcondylar Fossa Approach

BACKGROUND

It is essential to identify and be aware of the anatomy of the posterior condylar emissary vein (PCEV) for achieving an adequate operative field for the transcondylar fossa approach (TCFA).

OBJECTIVE

To describe the variations in the drainage patterns of PCEVs and the technical issues encountered in such cases.

METHODS

This was a retrospective analysis of the anatomy of PCEVs in 104 sides in 52 cases treated by the TCFA. Preoperative findings of multidetector-row computed tomography (CT) and CT venography (CTV) were compared with the intraoperative findings. The drainage patterns were classified as 5 types: the sigmoid sinus (SS), jugular bulb (JB), occipital sinus (OS), anterior condylar emissary vein (ACEV), and marginal sinus (MS).

RESULTS

The SS, JB, ACEV, and OS types were observed in 33 (31.7%), 42 (40.3%), 8 (7.7%), and 1 (1.0%) side(s), respectively. One side (1.0%) each had combined drainage from MS and JB, and ACEV and JB, respectively. In 17 sides (16.3%), the PCEVs and posterior condylar canals could not be identified on CT and CTV.

CONCLUSIONS

Preoperative CT and CTV findings correlated well with the intraoperative findings. To make a sufficient operative field for TCFA, PCEVs should be appropriately dealt with based on the preoperative knowledge of their running course, pattern, and origin.

Impacts of pressure bonding fixation on a bone flap depression and resorption in patients with craniotomy

Fixation of bone flaps after craniotomy is a routine part of every neurosurgical procedure. Common problems encountered are bone flap depression and resorption. Authors performed the pressure-bonding bone flap fixation (PBFF) using absorbable craniofix (AC) and hydroxyapatite wedge (HW). The aim of the present study is to evaluate the efficacy of PBFF to prevent a bone flap depression and resorption in patients treated with craniotomy. Four-hundred fifty-four patients underwent craniotomies. Authors collected the following data: age, sex, type of craniotomy, what kind of surgery, whether bypass surgery was performed, whether surgery was the initial, whether AC and the HW were used, bone flap depression and resorption at 6-month after the craniotomy. PBFF was defined as a bone flap fixation using both AC and HW to impress a bone flap to forehead. The mean age was 62±13years and 404 (89%) patients were women. PBFF was performed in 71 patients (16%), either AC or HW was used in 141 (31%), only AC was used in 116 (25%), and only HW was used in 25 (5.5%). At 6-month after the surgery, a bone flap depression was seen in 38 patients (8.4%), and a bone flap resorption was seen in 66 (15%). Multivariate analysis showed that only a PBBF showed a negative correlation with bone flap depression (p=0.044) and resorption (p=0.011). The results of the present study showed that PBFF reduced a bone flap depression and resorption and provided excellent postoperative cosmetic results.

Radical resection of a craniopharyngioma via the extradural anterior temporal approach with zygomatic arch osteotomy

BACKGROUND

Though the extradural anterior temporal approach (EDATA) with zygomatic osteotomy is useful, there are only few reports of this approach being used for craniopharyngioma resection. Herein, we report our surgical case series and the technical importance of EDATA for the radical removal of a craniopharyngioma.

METHODS

We report 7 cases of craniopharyngiomas treated surgically between April 1999 and October 2015. The surgical approaches, clinical presentation, pre and postoperative radiographic examination results, surgical outcomes, and morbidity were analyzed.

RESULTS

The mean follow-up period was 89.1 months. The surgical approach was EDATA with zygomatic osteotomy in 4, combined interhemispheric translamina terminalis approach (IHTLA) and trans-sylvian anterior temporal approach (ATA) in 2, and IHTLA in 1 patient. Complete tumor resection was achieved in all cases, without any recurrence during the follow-up period. Transient morbidities were oculomotor nerve palsy in 2, and meningitis and hydrocephalus in 1 patient. There was 1 case of permanent morbidity due to hydrocephalus that needed a ventriculoperitoneal shunt, and 1 case of blindness on the operative side. Visual acuity and visual field improved in 4 cases, showed no change in 2 cases, and deteriorated in 1 case. Though the pituitary stalk was preserved in 2 cases, all 7 cases needed total hormone replacement therapy.

CONCLUSION

EDATA with zygomatic osteotomy ensures sufficient mobility of the internal carotid artery, and provides a good lateral and look up operative view. Hence, it can be used effectively for radical resection of craniopharyngiomas through the opticocarotid space and retrocarotid space.

Pharmacological Properties of Propiverine Contribute to Improving Lower Urinary Tract Dysfunctions in Rats with Spinal Cord Injuries

Patients with spinal cord injury (SCI) usually develop lower urinary tract dysfunctions, including detrusor overactivity which is also known to be a risk factor for upper urinary tract dysfunction. Antimuscarinic agents, such as propiverine, have been used clinically for the treatment of detrusor overactivity. Also, propiverine has been known to possess antagonistic activity against L-type Ca²⁺ channels and transient receptor potential vanilloid subtype 1 (TRPV1), in addition to activity against muscarinic receptors. These mechanisms of action may contribute to improving detrusor overactivity in SCI. We therefore investigated the effects of antagonists of these mechanisms on non-voiding contraction (NVC) in SCI rats that are similar to clinical cases of detrusor overactivity, and considered whether these action mechanisms contribute to the incidence of NVC in SCI. Cystometry was performed in rats 4 weeks after spinal transection. Urinary functions were evaluated before and after intravenous administration of propiverine and specific antagonists for muscarinic receptors (atropine), L-type Ca²⁺ channels (verapamil), and TRPV1 (capsazepine). Propiverine markedly decreased the amplitude pressure of NVC in SCI rats, which was partially inhibited by atropine. Verapamil also suppressed the amplitude pressure of NVC to the same degree as propiverine. NVC disappeared almost completely after C-fiber desensitization, although capsazepine exerted no evident effects. These findings suggest that muscarinic receptors, L-type Ca²⁺ channels, and C-fiber afferent nerves contribute to the incidence of detrusor overactivity in SCI, and a drug that has multiple antagonistic effects, such as propiverine, is very effective for the treatment of lower urinary tract dysfunctions in SCI.

"Reverse" bypass using a naturally formed "bonnet" superficial temporal artery in symptomatic common carotid artery occlusion: a case report

We herein describe a patient with symptomatic common carotid artery occlusion who underwent a reverse superficial temporal artery (STA)-middle cerebral artery (MCA) single bypass using a naturally formed “bonnet” STA. The surgical procedure was performed without difficulty, and no further neurological deterioration was observed after surgery. In practice, this case highlights that the reverse STA-MCA bypass can be achieved safely and less invasively using a naturally formed “bonnet” STA.

Chronic encapsulated intracerebral hematoma associated with cavernous malformation

Chronic encapsulated intracerebral hematoma (CEIH) is a rare cerebrovascular disease that behaves as a slowly expanding lesion with a gradual onset. It is well established that CEIH is associated with arteriovenous malformations; however, CEIH associated with cavernous malformation (CM) is extremely rare. We herein report a case of CEIH associated with CM, and discuss its pathogenesis. A 12-year-old female was admitted to our hospital because of a one week history of progressive headache and nausea. Brain computed tomography scan and magnetic resonance imaging showed an intracerebral hematoma surrounded by edema in the right frontal lobe. One week later, her headache and nausea worsened, and a brain computed tomography scan revealed the enlargement of hematoma. A right frontal craniotomy was performed. The capsule, mass, and hematoma were totally removed. Histological examination confirmed the diagnosis of CEIH associated with CM. Immunohistochemical analysis revealed increased expression of vascular endothelial growth factor (VEGF) and the VEGF receptor-1 in the endothelium and fibroblasts. Our findings suggest that the activated VEGF pathway might have positively contributed to development of CEIH in the present patient.

A surgical case of paraclinoid carotid aneurysm associated with ipsilateral cervical internal carotid artery dissection

This report presents a 60-year-old with a large paraclinoid carotid aneurysm associated with cervical interal carotid artery (ICA) dissection (CICAD). She had a fall while riding a bicycle and hit her head on the ground. Computed tomography scan done at another facility showed a round mass lesion near the sella. Her medical history revealed gradual decrease in left eye vision since two years. Left carotid artery digital subtraction angiography demonstrated a CICAD with an intimal flap and a large paraclinoid aneurysm (15.5 mm in size). She underwent a high-flow bypass with a so-called double-insurance bypass and proximal ligation of the cervical ICA and the postoperative course was uneventful. She was discharged without any new neurological deficits. We suggest that the possible nature of carotid artery dissection (CAD)-related hemodynamic changes should be taken into consideration in cases of intracranial aneurysm associated with CAD.

Vestibular schwannoma with repeated intratumoral hemorrhage

Repeated hemorrhage from a vestibular schwannoma is very rare. We report a 15-year-old male, to our knowledge the fourth known patient with repeated hemorrhage of vestibular schwannoma, who presented with rapidly progressive right-sided hearing loss and tinnitus. MRI showed a mass lesion in the right cerebellopontine angle. T1-weighted and T2-weighted MRI revealed a hyperintense intratumoral area, indicating subacute hemorrhage within the tumor. Nine weeks after the initial onset, the patient again presented with a sudden onset headache, nausea, and ataxia. A CT scan showed recurrence of an intratumoral hemorrhage. A subtotal resection was achieved. A histopathological examination of the resected specimen showed typical features of schwannoma. We review the pertinent literature and discuss the features of repeated hemorrhage from a vestibular schwannoma.

[Chronic subdural hematoma--recurrence and prevention]

Chronic subdural hematoma is one of the most common disorders observed in routine neurosurgical care. In the vast majority of cases, this disorder is treated by surgical evacuation, which usually yields a good prognosis. However, the recurrence rates after this initial procedure range from approximately 5% to 30%. In this study, we focused on the recurrence rate of chronic subdural hematoma and its prevention. We reviewed the risk factors for recurrence, surgical procedures used, perioperative management, timing of operation, and medical treatment.

Cloning, expression, and characterization of a family 52 beta-xylosidase gene (xysB) of a multiple-xylanase-producing bacterium, Aeromonas caviae ME-1

A lambda phage genomic library of Aeromonas caviae ME-1, a multiple-xylanase-producing bacterium, was screened for xylan degradation activities. We isolated one clone, B65, which had weak xylanase activity, by the DNS method, but gave no visible bands on zymogram assay using SDS-xylan-PAGE. Based on TLC analyses of enzymatic products and some glycosidase assays using p-nitrophenyl substrates, we established that pB65 encodes a beta-xylosidase gene. In the nucleotide sequence analysis, we found a 2190-bp open reading frame (ORF) named xysB. XysB protein is similar to some beta-xylosidases, which are categorized in the glycosyl hydrolase family 52. Another ORF (xyg), that showed similarity to the family 67 alpha-glucuronidase, was also found downstream of the xysB gene. The xysB ORF and its promoter region were cloned into the pT7-Blue vector and the transformant cells had beta-xylosidase activity. The relative molecular mass were estimated to be 75 kDa by SDS-PAGE and 159 kDa by gel filtration. These data showed that XysB has a dimeric structure of 80,697 Da subunits. This enzyme showed optimal activity at 50 degrees C and pH 6.0. It was stable below 40 degrees C and pH 5-8. The Km and Vmax were calculated to be 0.34 mM and 33 nmol x min(-1) x microg(-1), respectively. This enzyme also showed transglycosylation activity against X3 and produced X4 and X5.

Physiological and morphometric analyses of neuropathy in sucrose-fed OLETF rats

To investigate the characteristic features of diabetic neuropathy in type 2 diabetes mellitus, Otsuka Long-Evans Tokushima fatty (OLETF) rats, an animal model of human type 2 diabetes mellitus, and non-diabetic Long-Evans Tokushima Otsuka (LETO) rats were fed with or without sucrose and/or an aldose reductase inhibitor, [5-(3-thienyl) tetrazol-1-yl] acetic acid (TAT), for 24 weeks, and physiological, biochemical and morphological assessments were performed. Sucrose administration caused remarkable hyperglycemia in OLETF rats but not in LETO rats. Sucrose-fed OLETF rats demonstrated delayed nerve conduction velocity, decreased coefficient of variation of R-R interval, reduced sciatic nerve blood flow, increased platelet aggregation activity, a lower concentration of erythrocyte 2,3-diphosphoglycerate, and decreased Na+/K+-ATPase activity in sciatic nerves, compared with the non-sucrose-fed OLETF and LETO rats. TAT prevented all these deficits except hyperglycemia. Sorbitol and fructose accumulation and myo-inositol depletion in tail nerves of sucrose-fed OLETF rats were ameliorated by TAT. Myelinated fiber size and density in sural nerves of sucrose-fed OLETF rats were decreased and increased, respectively, compared with non-sucrose-fed OLETF and LETO rats. These morphological abnormalities were normalized by TAT. These observations suggest that the sucrose-fed OLETF rat developed diabetic neuropathy not only electrophysiologically but also histologically, and that an aldose reductase inhibitor, TAT, possesses therapeutic value for the treatment of diabetic neuropathy.

The lipoprotein lipase activator, NO-1886, suppresses fat accumulation and insulin resistance in rats fed a high-fat diet

AIMS/HYPOTHESIS

Fat balance is critical in the aetiology of obesity and related diseases. Lipoprotein lipase is of major importance in lipid metabolism. The aim of this study was to investigate the long-term effects of the lipoprotein lipase activator, NO-1886, on substrate utilisation, adiposity and insulin action in rats fed a high-fat diet.

METHODS

Male, Sprague-Dawley rats were fed for 10 weeks on a chow diet or a high-fat diet with, or without, NO-1886 (50 mg x kg(-1) x day(-1)). Weight gain, fat accumulation and both hormone-sensitive and lipoprotein, lipase activities were measured. Insulin action was assessed by the euglycaemic hyperinsulinaemic clamp and metabolic rate/substrate utilisation by open-circuit respirometry.

RESULTS

Compared with chow-fed controls, a high-fat diet increased weight gain, an effect lessened by NO-1886 [weight gain (g): chow, 37 +/- 3, high-fat, 222 +/- 9; high-fat + NO-1886, 109 +/- 6, all groups differed p < 0.001]. A similar pattern existed for fat accumulation [visceral fat (g): chow, 35.9 +/- 3.2; high-fat, 81.9 +/- 6.6; high-fat + NO-1886, 52.3 +/- 4.7, p < 0.01 high-fat vs the other groups]. A high-fat diet induced wholebody insulin resistance (clamp glucose infusion rate: 4.8 +/- 1.3 mg x kg(-1) x min(-1) vs 10.6 +/- 1.1 for the chow group, p < 0.01) with NO-1886 lessening this effect (8.3 +/- 0.5, p < 0.05 vs high-fat). The 24-h respiratory quotient was lower in the high-fat + NO-1886 group (0.825 +/- 0.010) compared with high-fat alone (0.849 +/- 0.004, p < 0.05). A high-fat diet increased lipoprotein and hormone-sensitive, lipase activities in epididymal fat, an effect not altered by NO-1886. In myocardium and skeletal muscle a high-fat diet lowered lipoprotein lipase activity, an effect lessened by NO-1886.

CONCLUSION/INTERPRETATION

Lipoprotein lipase activators could have potential benefits for the treatment of obesity by increasing fat utilisation.

A protein kinase C-beta-selective inhibitor ameliorates neural dysfunction in streptozotocin-induced diabetic rats

Increased protein kinase C (PKC) activity has been implicated in the pathogenesis of diabetic retinopathy and nephropathy. However, the role of PKC in diabetic neuropathy remains unclear. The present study was conducted to compare the effect of PKC inhibition by a PKC-beta-selective inhibitor, LY333531 (LY), on diabetic nerve dysfunction with that of an aldose reductase inhibitor, NZ-314 (NZ). Streptozotocin-induced diabetic rats were treated with or without LY and/or NZ for 4 weeks, and motor nerve conduction velocity (MNCV), coefficient of variation of R-R interval (CVR-R), sciatic nerve blood flow (SNBF), peak latencies of oscillatory potentials on electroretinogram, PKC activities in membranous and cytosolic fractions of sciatic nerves, and polyol contents in the tail nerves were measured. Untreated diabetic rats demonstrated delayed MNCV, decreased CVR-R, reduced SNBF, and prolonged peak latencies of oscillatory potentials. Treatment with LY as well as NZ prevented all these deficits in diabetic rats. There were no significant differences in PKC activities in membranous or cytosolic fractions of sciatic nerves between normal and diabetic rats. Treatment with neither LY nor NZ altered PKC activities. Nerve myo-inositol depletion in diabetic rats was ameliorated not only by NZ, but also by LY. These observations suggest that inhibition of PKC-beta by LY may have a beneficial effect in preventing the development of diabetic nerve dysfunction, and that this effect may be mediated through its action on the endoneurial micro-vasculature.

Effect of vitamin E and allylamine on the proliferation of cultured aortic smooth muscle cells from streptozotocin-induced diabetic rats

To investigate the effect of vitamin E on the proliferation activity of vascular smooth muscle cells (SMCs) in diabetes mellitus, [3H]-thymidine incorporation was measured in cultured SMCs isolated from normal and streptozotocin-induced diabetic rats treated with or without vitamin E and/or allylamine. Untreated diabetic rats demonstrated significantly elevated concentrations of serum total cholesterol, triglycerides and malondialdehyde (MDA). Allylamine caused a further increase in serum MDA. Treatment with vitamin E decreased the serum concentrations of triglycerides and MDA in both allylamine-treated and -untreated diabetic rats. [3H]-Thymidine incorporation in cultured SMCs from diabetic rats was significantly increased compared with that from normal rats. SMCs from allylamine-treated diabetic rats showed an enhanced increase in thymidine incorporation compared with that from untreated diabetic rats. The increase in thymidine incorporation in SMCs from untreated and allylamine-treated diabetic rats was significantly reduced by the treatment with vitamin E. These observations suggest that vitamin E has a preventive effect on the proliferation of vascular SMCs in diabetes, and that this effect may be mediated through an enhancement of free radical scavenging.

Effect of aldose reductase inhibitors on glucose-induced changes in sorbitol and myo-inositol metabolism in human neutrophils

AIM

To investigate the influence of glucose and the efficacy of two different aldose reductase (AR) inhibitors, epalrestat and SNK-860, on the polyol pathway and myo-inositol metabolism in human neutrophils.

METHODS

We incubated neutrophils with various concentrations of glucose and AR inhibitors. The neutrophils from healthy volunteers were incubated in the media containing 5-40 mmol/l glucose with or without an AR inhibitor. The sorbitol and myo-inositol contents, and myo-inositol uptake were measured by high performance liquid chromatography and radio isotope technique with 2-[3H]-myo-inositol.

RESULTS

After 2 h incubation, the sorbitol content increased with rising extracellular glucose concentrations, while the myo-inositol content decreased. Both AR inhibitors reduced the sorbitol content in neutrophils exposed to 40 mmol/l glucose medium. A 70% fall in the myo-inositol content in neutrophils exposed to 40mmol/glucose medium was attenuated approximately 40% by the addition of AR inhibitors. myo-Inositol uptake into neutrophils was inhibited by high glucose. AR inhibitors significantly ameliorated the decrease in myo-inositol uptake, but did not completely normalize it.

CONCLUSIONS

Our present in vitro studies showed that the glucose-induced metabolic alterations in human neutrophils were similar to those in tissues prone to diabetic complications, and that AR inhibitors effectively corrected glucose-induced imbalances of the polyol pathway and myo-inositol uptake in neutrophils. In addition, our study suggests that glucose-induced metabolic alterations may result in the neutrophil dysfunction and that an AR inhibitor may be capable ameliorating it.

Polyol pathway hyperactivity is closely related to carnitine deficiency in the pathogenesis of diabetic neuropathy of streptozotocin-diabetic rats

To investigate the relationship between polyol pathway hyperactivity and altered carnitine metabolism in the pathogenesis of diabetic neuropathy, the effects of an aldose reductase inhibitor, [5-(3-thienyl) tetrazol-1-yl]acetic acid (TAT), and a carnitine analog, acetyl-L-carnitine (ALC), on neural functions and biochemistry and hemodynamic factors were compared in streptozotocin-diabetic rats. Significantly delayed motor nerve conduction velocity, decreased R-R interval variation, reduced sciatic nerve blood flow and decreased erythrocyte 2, 3-diphosphoglycerate concentrations in diabetic rats were all ameliorated by treatment with TAT (administered with rat chow containing 0.05% TAT, approximately 50 mg/kg/day) or ALC (by gavage, 300 mg/kg/day) for 4 weeks. Platelet hyperaggregation activity in diabetic rats was diminished by TAT but not by ALC. TAT decreased sorbitol accumulation and prevented not only myo-inositol depletion but also free-carnitine deficiency in diabetic nerves. On the other hand, ALC also increased the myo-inositol as well as the free-carnitine content without affecting the sorbitol content. These observations suggest that there is a close relationship between increased polyol pathway activity and carnitine deficiency in the development of diabetic neuropathy and that an aldose reductase inhibitor, TAT, and a carnitine analog, ALC, have therapeutic potential for the treatment of diabetic neuropathy.