Publications by authors named "Nakagawara J"

Article Synopsis
  • Scientists want to understand how blood flows around arteriovenous malformations (AVMs) in the brain to treat them better.
  • They used a special scanning technique called PET to look at how blood and oxygen are working in patients with unruptured AVMs.
  • They found that their new method (DBFM) works well to ensure accurate measurements, making it a promising way to study blood flow changes in patients with AVMs.
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Cognitive impairment in adult patients with moyamoya disease (MMD) is sometimes overlooked and can occur in patients with no ischemic or hemorrhagic lesions. Better profiling and reliable diagnostic methods that characterize the group and associate the impairments and pathology of MMD are required in order to deliver appropriate treatments and support. The potential of I-iomazenil single-photon emission computed tomography (SPECT) for this issue has been reported in some studies, but the universality of this method remains unclear.

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This study was aiming at investigating the extent of neuronal damage in cases of traumatic brain injury (TBI) with diffuse axonal injury (DAI) using I-iomazenil(IMZ) SPECT and MRI. We compared the findings in 31 patients with TBI without any major focal brain lesions and 25 age-matched normal controls. Subjects underwent I-IMZ SPECT and MRI, and also assessment by cognitive function tests.

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Background: To evaluate the impact of three risk factors (age [≥75 years], renal impairment [creatinine clearance <50 ml/min], and low body weight [≤50 kg]) on the risk of any bleeding events, all-cause mortality, and stroke, non-central nervous system (non-CNS) systemic embolism (SE), and myocardial infarction (MI) in patients with nonvalvular atrial fibrillation (NVAF) treated with rivaroxaban in a real-world clinical setting.

Methods: The Xarelto Post-Authorization Safety and Effectiveness Study in Japanese Patients with Atrial Fibrillation (XAPASS) is a prospective, single-arm, observational study. Enrolled patients were divided into four subgroups by the number of risk factors.

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Cerebral hyperperfusion syndrome (CHS) after surgical clipping for cerebral aneurysm is a rare entity. The authors present a 76-year-old woman with a large left internal carotid-posterior communicating artery aneurysm. After successful clipping with temporary occlusion of the internal carotid artery, the patient exhibited motor aphasia.

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Background: The Xarelto Post-Authorization Safety and Effectiveness Study in Japanese Patients with Atrial Fibrillation (XAPASS) was designed to investigate safety and effectiveness during long-term follow-up of rivaroxaban treatment, using reduced doses compared with other global regions, in Japanese patients with non-valvular atrial fibrillation in real-world clinical practice.

Methods: In this prospective, open-label, single-arm, observational study, 11,308 patients with non-valvular atrial fibrillation newly prescribed rivaroxaban (15/10 mg once daily) at 1416 sites across Japan were enrolled and followed for a mean of 2.5 years.

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Background And Purpose: A transient ischemic attack (TIA) can occur without self-awareness of symptoms. We aimed to investigate characteristics of patients with a tissue-based diagnosis of TIA but having no self-awareness of their symptoms and whose symptoms were witnessed by bystanders.

Methods: We used data from the multicenter registry of 1414 patients with a clinical diagnosis of TIA.

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Article Synopsis
  • The study analyzed 5-year outcomes in patients with transient ischemic attack (TIA) or minor stroke, comparing Japanese patients to non-Japanese patients to identify variations based on ethnicity.
  • Japanese patients experienced higher rates of recurrent stroke and intracranial hemorrhage compared to their non-Japanese counterparts, while vascular death was less prevalent.
  • Key predictors for recurrent stroke in Japanese patients included age, diabetes, history of stroke or TIA, and congestive heart failure, indicating the need for tailored strategies to manage long-term stroke risks in this population.
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This sub-analysis of the XAPASS, a prospective, single-arm, observational study, aimed to evaluate relationships between body mass index (BMI) and safety (major bleeding and all-cause mortality) and effectiveness [stroke/non-central nervous system (non-CNS) systemic embolism (SE)/myocardial infarction (MI)] outcomes in Japanese patients with non-valvular atrial fibrillation (NVAF) receiving rivaroxaban. Patients were categorized according to BMI (kg/m) as underweight (< 18.5), normal weight (18.

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Background: It is important to understand the risk of thromboembolism and bleeding in patients with nonvalvular atrial fibrillation (NVAF) receiving direct oral anticoagulants; however, data on risk factors in Japanese patients are limited.

Methods: XAPASS (Xarelto Post-Authorization Safety and Effectiveness Study in Japanese Patients with Atrial Fibrillation) is a prospective observational study examining the safety and effectiveness of rivaroxaban in Japanese real-world clinical practice. We investigated risk factors for stroke/noncentral nervous system systemic embolism (non-CNS SE)/myocardial infarction (MI) and major bleeding using 1-year follow-up data.

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Introduction: Prior stroke is a risk factor for stroke and bleeding during anticoagulation in patients with atrial fibrillation (AF). Although rivaroxaban is widely prescribed to reduce their risk of stroke in patients with nonvalvular AF (NVAF), the real-world evidence on rivaroxaban treatment is limited. We aimed to examine the outcomes of rivaroxaban treatment in NVAF patients with prior ischemic stroke/transient ischemic attack (TIA) by using the data of the Xarelto Post-Authorization Safety and Effectiveness Study in Japanese -Patients with AF, a prospective, single-arm, observational study.

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Direct oral anticoagulants (DOACs), such as rivaroxaban, reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation (NVAF). However, it is still unclear whether the stroke reduction benefit outweighs the bleeding risk in elderly Japanese patients with NVAF. The Xarelto Post-Authorization Safety and Effectiveness Study in Japanese Patients with Atrial Fibrillation (XAPASS) was a real-world, prospective observational, post-marketing surveillance study on the safety and effectiveness of rivaroxaban in Japanese clinical practice.

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The approved dose of oral anticoagulant rivaroxaban for patients with non-valvular atrial fibrillation (NVAF) in Japan is 15 mg once daily (od) in patients whose creatinine clearance is ≥ 50 mL/min, but recent real-world studies have demonstrated that these patients often received less than the recommended dose due to bleeding concerns. The effect of under-dosing on safety and effectiveness outcomes remains unclear. We used 1-year follow-up data from the XAPASS, a real-world Japanese prospective, single-arm, observational study.

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Background: Rivaroxaban is a direct oral anticoagulant administered to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation (NVAF). The Xarelto Post-Authorization Safety and Effectiveness Study in Japanese Patients with Atrial Fibrillation (XAPASS) was a prospective, observational, post-marketing surveillance study that examined the safety and effectiveness of rivaroxaban in routine clinical practice. This sub-analysis of the XAPASS investigated the outcomes of patients with worsening renal function (WRF).

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Article Synopsis
  • TIAregistry.org is a global study focusing on patients who experienced a transient ischemic attack or minor stroke, with a specific analysis on Japanese patients' data at 1-year follow-up.
  • The study found significant differences between Japanese and non-Japanese patients in terms of risk factors for stroke: Japanese patients had higher rates of current smoking and stroke risk, while non-Japanese patients were more likely to have conditions like hypertension and dyslipidemia.
  • Key predictors of recurrent stroke in Japanese patients were identified as having prior congestive heart failure and regular alcohol consumption, suggesting the need for tailored risk management strategies for this group.
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Background and Purpose- The ring finger protein 213 gene ( RNF213) is a susceptibility gene for moyamoya disease and large-artery ischemic stroke in East Asia. We examined the prevalence and correlates of the RNF213 p.R4810K variant in patients with early-onset ischemic stroke in a Japanese single-center cohort.

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Background: CYP2C19variants are associated with the antiplatelet effects of clopidogrel against recurrent cardiovascular events. However, it remains unknown whether the elapsed time from stroke onset affects the relationship between the genetic variants and such events. To address this, we conducted a prospective cohort study to determine the effect ofCYP2C19variants on clinical outcomes in the chronic phase.

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Article Synopsis
  • A study in Japan aimed to investigate the early stroke risk in patients with small vessel occlusion-transient ischemic attack (TIA) and compare it with other causes of TIA.
  • It analyzed data from 1320 TIA patients, finding that those with small vessel occlusion had the highest rate of recurrent strokes at 7.8% within 30 days.
  • The research concluded that small vessel occlusion TIA significantly increases the risk of early stroke, especially when associated with acute small deep infarcts.
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Background: Although the efficacy and safety of the factor Xa inhibitor rivaroxaban for the prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation (NVAF) were shown in global and Japanese phase III clinical trials, safety and effectiveness data from unselected patients in everyday clinical practice are limited. The objective of the XAPASS (Xarelto Post-Authorization Safety & Effectiveness Study in Japanese Patients with Atrial Fibrillation) is to investigate the safety and effectiveness of rivaroxaban in Japanese real-world clinical practice.

Methods: The XAPASS is a prospective, single-arm, real-world observational study mandated by the Japanese authority as post-marketing surveillance.

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Background: O-oxygen inhalation PET is unique in its ability to provide fundamental information regarding cerebral hemodynamics and energy metabolism in man. However, the use of O-oxygen has been limited in a clinical environment largely attributed to logistical complexity, in relation to a long study period, and the need to produce and inhale three sets of radiopharmaceuticals. Despite the recent works that enabled shortening of the PET examination period, radiopharmaceutical production has still been a limiting factor.

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Background and Purpose- Patients with transient ischemic attack (TIA) occasionally show nonfocal symptoms, such as unconsciousness, amnesia, and unsteadiness. The purpose of this study was to clarify the characteristics and prognosis of patients with TIA with nonfocal symptoms, using data from the PROMISE-TIA (Prospective Multicenter Registry to Identify Subsequent Cardiovascular Events After Transient Ischemic Attack). Methods- Patients with TIA within 7 days of onset were consecutively enrolled in the Japanese nationwide registry.

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Background: The phase III Japanese Rivaroxaban Once-Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (J-ROCKET AF) showed that the rivaroxaban group had a lower event rate of intracranial bleeding than the warfarin group and that rivaroxaban was noninferior to warfarin for the principal safety outcome. However, safety and effectiveness data from unselected patients with AF in everyday clinical practice in Japan are lacking.

Methods: The Xarelto Post-Authorization Safety & Effectiveness Study in Japanese Patients with Atrial Fibrillation (XAPASS) is a real-world, prospective, single-arm, observational study mandated by the Japanese authority as postmarketing surveillance.

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Background: A transient visual symptom (TVS) is a clinical manifestation of transient ischemic attack (TIA). The aim of this study was to investigate differences in clinical characteristics among subtypes of TVS using multicenter TIA registry data.

Materials And Methods: Patients with TIA visiting within 7 days of onset were prospectively enrolled from 57 hospitals between June 2011 and December 2013.

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Objectives: This cross-sectional survey explored the characteristics and outcomes of direct oral anticoagulant (DOAC)-associated nontraumatic intracerebral hemorrhages (ICHs) by analyzing a large nationwide Japanese discharge database.

Methods: We analyzed data from 2,245 patients who experienced ICHs while taking anticoagulants (DOAC: 227; warfarin: 2,018) and were urgently hospitalized at 621 institutions in Japan between April 2010 and March 2015. We compared the DOAC- and warfarin-treated patients based on their backgrounds, ICH severities, antiplatelet therapies at admission, hematoma removal surgeries, reversal agents, mortality rates, and modified Rankin Scale scores at discharge.

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