Published papers

We encountered a-27-year-old female patient who developed refractory severe headache and photo-phobia after the first dose of COVID-19 vaccine. Despite her prior history of migraine, we diagnosed COVID-19 vaccine-induced aseptic meningitis. Symptoms were significantly resolved after methylpred-nisolone therapy. On reviewing the literature, we could find only nine similar cases, with over half of them affecting women aged 20–40 years. Although uncommon, aseptic meningitis should be suspect-ed in patients with persistent or delayed onset of headache following COVID-19 vaccination.

Background: The differences in the characteristics of ischemic stroke associated with a mobile versus nonmobile residual left atrial thrombus (LAT) are unclear. We investigated whether the mobility of an LAT detected by transthoracic echocardiography is associated with the clinical features of stroke. Methods: This study included 20 consecutive patients with nonvalvular atrial fibrillation who were ad-mitted to our hospital for treatment of acute ischemic stroke and then found to have an LAT on transthoracic echocardiography. The patients were divided into two groups: those with a mobile LAT (Group M) and those with a nonmobile LAT (Group N). The clinical, neuroradiological, and echocar-diographic variables were assessed. Results: The LAT was mobile in 11 patients (Group M) and nonmobile in nine patients (Group N). The median National Institutes of Health Stroke Scale score on admission was higher in Group M than N (17 vs. 7, respectively; p=0.196). Four patients in Group M and one in Group N developed in-hospital stroke recurrence (36% vs. 11%, respectively; p=0.319). The prevalence of large vessel occlusion (15 events in Group M and 10 events in Group N, including in-hospital recurrent events) was significantly higher in Group M than N (73% vs. 30%, respectively; p=0.049), which seemed to lead to poorer functional outcomes in Group M than N (ratio of modified Rankin scale score of 0-2 at discharge: 18% vs. 44%, respectively; p=0.336). Conclusions: The mobility of LAT may affect stroke severity in patients with nonvalvular atrial fibrillation.

Objectives: This study aimed to determine whether oral anticoagulant therapy affects the severity of cerebral infarction at onset in elderly patients with non-valvular atrial fibrillation. Materials and Methods: This retrospective study included 330 elderly patients (aged ≥75 years) who were hospitalized for cardioembolic stroke due to non-valvular atrial fibrillation. Patients’ medical history, stroke severity at onset (National Institutes of Health Stroke Scale score), and the prevalence of large vessel occlusion were compared between patients who received oral anticoagulant therapy (n = 109) and those who did not receive oral anticoagulant therapy (n = 221). Results: Stroke severity was significantly lower in patients who received anticoagulants than in those who did not receive anticoagulants (6 versus 12; P = 0.021). Patients who did not receive anticoagulants had a significantly higher prevalence of large vessel occlusion (52% versus 37%; P = 0.010). After resampling based on propensity score matching, both median stroke severity (7 versus 12; P = 0.046) and large vessel occlusion prevalence (36% versus 57%; P = 0.019) were significantly lower in patients who received anticoagulant therapy. Conclusions: The results of this study suggest that elderly patients with non-valvular atrial fibrillation who are administered oral anticoagulant therapy before the onset of cerebral infarction develop less severe stroke than those who are not receiving oral anticoagulant therapy. Thus, oral anticoagulant therapy should be actively considered in patients with non-valvular atrial fibrillation as it does not only prevents cerebral embolism, but also reduces the risk of severe sequelae.

Recent advances in pathophysiology suggest that a pathological atrial substrate can cause embolic stroke even in patients without atrial fibrillation (AF). This pathological condition is called “atrial cardiopathy”, which indicates atrial structural and functional disorders that can precede AF. The objective of this narrative review was to provide a current overview of atrial cardiopathy and cryptogenic stroke. We searched the PubMed database and summarized the recent findings of the identified studies, including the pathogenesis of atrial cardiopathy, biomarkers of atrial cardiopathy, relationship between atrial cardiopathy and cryptogenic stroke, and therapeutic interventions for atrial cardiopathy. Abnormal atrial substrate (atrial cardiopathy) that leads to AF can result in embolic stroke before developing AF, and may explain the source of cryptogenic stroke in some patients. Although there are several potential biomarkers indicative of atrial cardiopathy, P-wave terminal force in lead V1 (>5,000 μV* ms), N-terminal pro-brain natriuretic peptide (>250 pg/ml), and left atrial enlargement are currently promising biomarkers for the diagnosis of atrial cardiopathy. Because the optimal combination and thresholds of biomarkers for diagnosing atrial cardiopathy remain uncertain, atrial cardiopathy represents a spectrum disorder. The concept of atrial cardiopathy appears to be most valuable as a starting point for therapeutic intervention to prevent stroke. Validation of the diagnosis of atrial cardiopathy and whether it can be used as a new therapeutic target for direct oral anticoagulants are currently being covered in the ARCADIA trial.

Objective: This study was undertaken to determine the excess risk of antithrombotic-related bleeding due to cerebral small vessel disease (SVD) burden. Methods: In this observational, prospective cohort study, patients with cerebrovascular or cardiovascular diseases taking oral antithrombotic agents were enrolled from 52 hospitals across Japan between 2016 and 2019. Baseline multimodal magnetic resonance imaging acquired under prespecified conditions was assessed by a central diagnostic radiology committee to calculate total SVD score. The primary outcome was major bleeding. Secondary outcomes included bleeding at each site and ischemic events. Results: Of the analyzed 5,250 patients (1,736 women; median age = 73 years, 9,933 patient-years of follow-up), antiplatelets and anticoagulants were administered at baseline in 3,948 and 1,565, respectively. Median SVD score was 2 (interquartile range = 1–3). Incidence rate of major bleeding was 0.39 (per 100 patinet-years) in score 0, 0.56 in score 1, 0.91 in score 2, 1.35 in score 3, and 2.24 in score 4 (adjusted hazard ratio [aHR] for score 4 vs 0 = 5.47, 95% confidence interval [CI] = 2.26–13.23), that of intracranial hemorrhage was 0.11, 0.33, 0.58, 0.99, and 1.06, respectively (aHR = 9.29, 95% CI = 1.99–43.35), and that of ischemic event was 1.82, 2.27, 3.04, 3.91, and 4.07, respectively (aHR = 1.76, 95% CI = 1.08–2.86). In addition, extracranial major bleeding (aHR = 3.43, 95% CI = 1.13–10.38) and gastrointestinal bleeding (aHR = 2.54, 95% CI = 1.02–6.35) significantly increased in SVD score 4 compared to score 0. Interpretation: Total SVD score was predictive for intracranial hemorrhage and probably for extracranial bleeding, suggesting the broader clinical relevance of cerebral SVD as a marker for safe implementation of antithrombotic therapy. ANN NEUROL 2024;95:774–787.

Although the severity of acute cerebral infarction varies in patients receiving direct oral anticoagulants (DOACs), no practical method to predict the severity has been established. We analyzed retrospectively the relationship between cardioembolic cerebral infarction severity and coagulation indicators in patients treated with DOACs. We assessed the anticoagulation effect of DOACs using the activated partial thromboplastin time (APTT), prothrombin time (PT), and prothrombin time international standardized ratio (PT-INR) in 71 patients with cardioembolic cerebral infarction admitted to our hospital between January 2015 and December 2019. The participants were divided into a prolongation group (prolonged APTT for oral thrombin inhibitors or prolonged PT for oral factor Xa inhibitors, n =37) and a normal group (no prolongation of coagulation markers, n =34). Of the 71 patients, 21 (30%) and 50 (70%) were using oral thrombin and oral factor Xa inhibitors, respectively. PT, PT-INR, and APTT were significantly higher in the prolongation group (PT: 17.4 ± 5.1 vs. 12.8 ± 1.4 s, P < 0.001; PT-INR: 1.5 ± 0.5 vs. 1.1 ± 0.1, P < 0.001; APTT: 44.8 ± 26.4 vs. 30.4 ± 4.1 s, P = 0.003). The median National In-stitutes of Health Stroke Scale (NIHSS) score on admission and the prevalence of large vessel occlusion were significantly lower in the prolongation group (NIHSS: 2.0 vs. 9.5, P = 0.007; large vessel occlusion: 27% vs. 53%, P = 0.031). The prevalence of large vessel occlusion was low and stroke severity was mild in patients undergoing DOAC therapy with prolongation of coagulation assay markers upon onset of cardioembolic cerebral infarction.

Atrial fibrillation (AF) is a common disease encountered in daily practice; however, few patients with AF received oral anticoagulant (OAC) therapy. This study focused on differences in OAC prescriptions and influencing factors between specialists (neurological and cardiovascular) and non-specialists. A retrospective comparative analysis was conducted on 480 patients with acute cardioembolic stroke caused by non-valvular AF who were admitted to our hospital between January 1, 2015, and December 31, 2020. All patients had visited our hospital or other hospitals for their underlying diseases. Overall, 232 (specialist group SG) and 248 patients (non-specialist group NSG) were examined by specialists and non-specialists, respectively. The NSG had a significantly lower percentage of OAC prescriptions on admission than the SG (P < 0.01), even after propensity score matching. Factors influencing OAC prescription in the SG were age, hypertension, paroxysmal AF, dementia, CHADS2 score, and antiplatelet drug use, while those in the NSG were a history of cerebral infarction, paroxysmal AF, dementia, and antiplatelet drug use [SG: age, odds ratio (OR) 0.919, 95% confidence interval (CI) 0.865–0.976; hypertension, OR 0.266, 95% CI 0.099–0.713; paroxysmal AF, OR 0.189, 95% CI 0.055–0.658; dementia, OR 0.253, 95% CI 0.085–0.758; CHADS2 score, OR 2.833, 95% CI 1.682–4.942; and antiplatelet drug use, OR 0.072, 95% CI 0.025–0.206; NSG: cerebral infarction, OR 5.940, 95% CI 1.581–22.309; paroxysmal AF, OR 0.077, 95% CI 0.010–0.623; dementia, OR 0.077, 95% CI 0.014–0.438; and antiplatelet drug use, OR 0.024, 95% CI 0.004–0.152]. In conclusion, the OAC prescription rate was higher in patients with non-valvular AF whose family physicians were specialists at the time of cerebral infarction onset. In addition, in the SG, advanced age and hypertension were associated with not prescribing OAC, whereas a higher CHADS2 score was associated with the prescription of OACs. In the NSG, a history of cerebral infarction was associated with the prescription of OACs. Further, paroxysmal AF, antiplatelet drug use, and dementia were associated with non-OAC therapy in both the groups.