Yohsuke Horiuchi

Clinical review of 37 patients with medullary infarction.

BACKGROUND Clinical features of medullary infarction were compared between patients with lateral medullary infarction and medial medullary infarction METHODS Thirty-seven patients with medullary infarction (29 with lateral medullary infarction and 8 with medial medullary infarction) who were admitted to our center between April 1, 2007 and March 31, 2010 were examined. Background factors, neurologic signs and symptoms, imaging findings, cause of disease, and outcomes were assessed for patients with lateral and those with medial medullary infarction. RESULTS Examination of the clinical symptoms and neurologic findings suggested that among patients with medial medullary infarction, few demonstrated all of the symptoms of Dejerine syndrome at onset, and many had lesions that were difficult to locate based only on neurologic findings. Both lateral and medial medullary infarction were frequently caused by atherothrombosis. However, cerebral artery dissection was observed in 31% of patients with lateral medullary infarction and 12.5% of those with medial medullary infarction. In 13% of patients with lateral and 37% of patients with medial medullary infarction, magnetic resonance imaging diffusion-weighted images on the day of onset did not show abnormalities, and the second set of diffusion-weighted images confirmed infarction lesions. For lateral medullary infarction, a more rostral lesion location was correlated with a poorer 90-day outcome. For medial medullary infarction, a more dorsal lesion location was correlated with a poorer 90-day outcome. CONCLUSIONS The diagnosis rate of medullary infarction using imaging examinations at onset--particularly medial medullary infarction--is not necessarily high. The imaging examinations need to be repeated for patients who are suspected to have medullary infarction based on neurologic signs and symptoms.

The CHA(2)DS(2)-VASc score reflects clinical outcomes in nonvalvular atrial fibrillation patients with an initial cardioembolic stroke.

BACKGROUND Whether the CHA(2)DS(2)-VASc score reflects severity or clinical outcomes in patients with an initial cardioembolic stroke associated with nonvalvular atrial fibrillation (NAVF) was investigated. METHODS This study included 327 patients hospitalized between April 2007 and March 2012 for an initial cardioembolic stroke associated with NVAF with no history of stroke. The National Institutes of Health Stroke Scale (NIHSS) score on admission and clinical outcome (modified Rankin Scale [mRS] score after 90 days) were retrospectively evaluated according to the CHA(2)DS(2)-VASc score. RESULTS CHA(2)DS(2)-VASc scores were 0, 3.1%; 1, 9.1%; 2, 24.5%; 3, 26%; 4, 20.8%; 5, 14.4%; and 6, 2.1%. The median NIHSS scores for CHA(2)DS(2)-VASc scores of 0-6 were 4.5, 8, 8, 10, 11, 17, and 23, respectively. Severity differed according to the CHA(2)DS(2)-VASc score. The clinical outcomes according to the CHA(2)DS(2)-VASc scores were as follows: score 0, mRS scores of 0-2 (80%) and 3-6 (20%); score 1, mRS scores of 0-2 (80%) and 3-6 (20%); score 2, mRS scores of 0-2 (64%) and 3-6 (36%); score 3, mRS scores of 0-2 (48%) and 3-6 (52%); score 4, mRS scores of 0-2 (28%) and 3-6 (72%); score 5, mRS scores of 0-2 (26%) and 3-6 (74%); and score 6, mRS scores of 0-2 (29%) and 3-6 (71%). The clinical outcome worsened as the CHA(2)DS(2)-VASc score increased. On logistic regression analysis, age, NIHSS score on admission, and thrombolytic therapy were related to a clinical outcome. CONCLUSIONS The severity of NVAF-induced initial cardioembolic stroke increased with higher CHA(2)DS(2)-VASc scores, and the outcomes were poor. The present study suggests that the CHA(2)DS(2)-VASc score may be useful not only for the evaluation of stroke risk but also for the prediction of clinical outcomes after stroke.

Human T lymphotropic virus type-1-associated myelopathy manifesting shortly after living-donor renal transplantation.

A 38-year-old woman experienced numbness in both lower extremities and spastic paralysis a few months after undergoing living-donor renal transplantation. The patient was negative for human T lymphotropic virus type-1 (HTLV-1) antibodies prior to the procedure; however, she was diagnosed with HTLV-1-associated myelopathy (HAM) based on positive serum and cerebrospinal fluid antibody titers after the surgery. Because the donor was also positive for HTLV-1 antibodies, the infection likely originated from the transplanted kidney. Clinical and imaging improvements were noted following the administration of interferon-α. HAM has been reported to occur after living-donor renal transplantation; however, there are no previous reports of onset within such a short period.

Treatment Outcomes of Tissue Plasminogen Activator Infusion for Branch Atheromatous Disease

BACKGROUND The objective of this study was to evaluate treatment outcomes of tissue plasminogen activator (t-PA) infusion for hyperacute branch atheromatous disease (BAD) within 3 hours after onset. METHODS A total of 152 BAD patients with lenticulostriate artery (LSA) or paramedian pontine artery (PPA) territory infarcts (LSA 114; PPA 38) were hospitalized between April 2007 and June 2012. Of these, 21 BAD patients (LSA 19; PPA 2) arrived at the hospital within 3 hours after onset, and, among these, 8 patients who received t-PA infusion (.6 mg/kg) were included in this study. All BAD patients who received t-PA infusion had LSA territory infarcts. RESULTS Six of 8 patients (75%) had improvement of neurologic findings within 60 minutes after t-PA infusion, but neurologic findings deteriorated within 24 hours in 4 of these patients (67%). In all patients with deterioration, diffusion-weighted imaging after 24 hours revealed infarct expansion. One patient (13%) had symptomatic intracranial hemorrhage. After 3 months, the modified Rankin Scale (mRS) score was 0 to 2 in 6 patients (75%) and 3 to 6 in 2 patients (25%). CONCLUSIONS With t-PA infusion for BAD, symptoms transiently improved, but the rate of symptom deterioration was high. The outcome after 3 months was relatively good.

Clinical Outcomes of Persistent and Paroxysmal Atrial Fibrillation in Patients with Stroke

BACKGROUND We compared the clinical outcomes of persistent atrial fibrillation (PeAF) and paroxysmal atrial fibrillation (PAF) in patients with cardioembolic stroke caused by nonvalvular atrial fibrillation (NVAF) because the nature of the fibrillation can cause persistent cerebral infarction. METHODS We classified 619 of 964 patients hospitalized with cardioembolic stroke between April 2007 and December 2013 within 24 hours of onset as having PeAF (n = 447) and PAF (n = 172) according to a retrospective analysis of their clinical records, including National Institutes of Health Stroke Scale (NIHSS) scores on admission, clinical outcomes (modified Rankin Scale [mRS] scores) at 90 days after admission, and major cerebral artery occlusion. RESULTS The PeAF group was significantly older (P < .001) and had a higher prevalence of hypertension (P = .007), diabetes (P = .039), heart failure (P = .004), previous coronary artery disease (P = .002) and cerebral infarction (P < .001), medication with anticoagulants (P < .001), and elevated blood glucose on admission (P = .002). Neurologic severity assessed by NIHSS scores on admission was significantly worse in the PeAF than in the PAF group (P < .001). Significantly more patients in the PAF group had favorable outcomes (mRS, 0-2) after 90 days (P < .001). The incidence of major cerebral artery occlusion was significantly higher in the PeAF group (P < .001). CONCLUSIONS Patients with PeAF and cardioembolic stroke due to NVAF had more severe neurologic deficits on admission, more frequent major arterial occlusion, and poorer outcomes than those with PAF.

Relationship of Obesity to Recanalization after Hyperacute Recombinant Tissue-Plasminogen Activator Infusion Therapy in Patients with Middle Cerebral Artery Occlusion

BACKGROUND This was a retrospective analysis of factors related to recanalization after hyperacute recombinant tissue-plasminogen activator (rt-PA) infusion therapy in patients with middle cerebral artery occlusion. METHODS Of the 50 patients (39 males and 11 females; mean age 70 ± 11 years) with cerebral infarction who were able to undergo diffusion-weighted magnetic resonance imaging (MRI)/magnetic resonance angiography (MRA) of the head within 24 hours of starting rt-PA infusion therapy while hospitalized at our center between April 2007 and October 2010, 23 patients (18 males and 5 females; mean age 71 ± 9.4 years) with hyperacute cerebral infarction with findings of obstruction in the proximal segment of the middle cerebral artery (MCA-M1) served as subjects. RESULTS Of the 23 patients with MCA occlusion, 13 (57%) were recanalized. Analysis of factors related to recanalization revealed a significant difference (P = .019) for obesity (body mass index >25 kg/m(2)), with significantly more obese patients in the nonrecanalized group than in the recanalized group. The study revealed no significant differences in other factors between the 2 groups. CONCLUSIONS The results suggest that obesity may be involved in recanalization after hyperacute rt-PA infusion therapy in patients with MCA occlusion.

Research Article: Clinical Characteristics of Isolated Anterior Cerebral Artery Territory Infarction Due to Arterial Dissection

BACKGROUND Isolated brain infarction in the anterior cerebral artery (ACA) territory is rare, and its etiology has not yet been fully elucidated. Thus, we aimed to determine the etiologic and clinical characteristics of patients with isolated ACA territory infarction due to arterial dissection. METHODS Of 2315 patients with acute cerebral infarction admitted to our hospital between April 2007 and September 2013, 34 patients (1.5%; 28 men, 6 women; mean age, 65 ± 15 years) suffered isolated ACA territory infarction. We performed cranial magnetic resonance (MR) imaging and MR angiography for all the patients. Whenever possible, we also performed 3-dimensional computed tomography angiography, digital subtraction angiography, and MR cisternography to diagnose the stroke subtype. RESULTS The stroke subtypes of the 34 patients with isolated ACA territory infarction were atherothrombotic infarction, cardioembolic infarction, arterial dissection, and unclassified in 11 patients (32%), 11 patients (32%), 11 patients (32%), and 1 patient (3%), respectively. The mean ages at onset were 48 ± 9 and 72 ± 11 years in the dissection and nondissection groups, respectively (P < .001). Headaches were present at onset in 4 patients (36%) and 1 patient (4%) with and without dissection, respectively (P = .026). Blood pressure at onset was significantly higher among patients with dissection (systolic, 179 ± 34 mm Hg; diastolic, 102 ± 17 mm Hg) than among patients without dissection (systolic, 155 ± 30 mm Hg; diastolic, 86 ± 21 mm Hg; P < .05), and d-dimer values were significantly lower among patients with dissection (P = .034). Favorable clinical outcome (modified Rankin Scale score, 0-2) at discharge was achieved in 9 patients (82%) and 10 patients (43%) with and without dissection, respectively (P = .035). CONCLUSIONS Patients with isolated ACA territory infarction demonstrated a relatively high frequency of dissection (32%). Patients with dissection were younger, had a higher frequency of headaches, and demonstrated more favorable prognoses than patients without dissection.

CHADS2 score/CHA2DS2-VASc score and major artery occlusion in cardioembolic stroke patients with nonvalvular atrial fibrillation

Objective The associations between the CHADS2 score/ CHA2DS2-VASc score, and the presence of cerebral vessel occlusion on admission were examined in cardioembolic stroke patients with nonvalvular atrial fibrillation. Methods The subjects were 546 consecutive patients hospitalized between April 2007 and December 2012 with onset of cardioembolic stroke associated with nonvalvular atrial fibrillation within 24 h. The associations between the CHADS2 score/CHA2DS2-VASc score and the presence of occluded cerebral vessels on magnetic resonance angiography were evaluated retrospectively. Occluded cerebral vessels were classified into the internal carotid artery, middle cerebral artery (M1, M2), basilar artery, and other (anterior cerebral artery [A1], posterior cerebral artery [P1], vertebral artery). Results Major artery occlusion was seen in 52% of patients with CHADS2 score 0, 52% of patients with score 1, 57% with score 2, 75% with score 3, and 75% with score ≥4. As for the CHA2DS2-VASc score, major artery occlusion was seen in 62% of patients with score 0, 49% with score 1, 53% with score 2, 53% with score 3, 65% with score 4, 71% with score 5, and 82% with score ≥6. The incidence of concurrent major arterial occlusion increased as both scores rose. When classified by occluded blood vessel, the incidence of concurrent internal carotid artery occlusion increased as both the CHADS2 and CHA2DS2-VASc scores increased. Conclusion As the CHADS2 and CHA2DS2-VASs scores increased, the incidence of concurrent major arterial occlusion, particularly internal carotid artery occlusion, increased in patients with cardioembolic stroke associated with nonvalvular atrial fibrillation.

Clinical Features of Ischemic Stroke during Treatment with Dabigatran: An Association between Decreased Severity and a Favorable Prognosis.

OBJECTIVE Anticoagulation therapy with warfarin is associated with a favorable prognosis in ischemic stroke. Dabigatran, a new oral anticoagulant, is widely used to prevent ischemic stroke in non-valvular atrial fibrillation (NVAF) patients. However, its association with decreased severity and a favorable prognosis once ischemic stroke has occurred remains unknown. METHODS We retrospectively reviewed all the patients with NVAF-associated ischemic stroke admitted to our hospital from April 2011 to December 2014 and included those who received dabigatran therapy. We assessed whether the patients were under regular use of the drug or discontinuance and classified them into 2 groups, the treatment and discontinuation groups. Clinical data, including the age, sex, ASCOD stroke phenotype, NVAF type, prescribed drug dose, comorbidities, CHADS2 score, renal function, National Institute of Health Stroke Scale (NIHSS) score on admission, modified Rankin scale (mRS) score at discharge, D-dimer, and brain natriuretic peptide, were investigated and compared between the groups. RESULTS Nine patients were under regular dabigatran therapy, and 6 were under discontinuance of the drug. The age, sex, ASCOD stroke phenotype, NVAF type, comorbidities, renal function, and CHADS2 scores did not differ between the 2 groups; however, the NIHSS scores were significantly lower in the treatment group. The mRS scores at discharge were additionally decreased in the treatment group. Moreover, the D-dimer scores were lower in the treatment group, thus suggesting a possible role in the decreased stroke severity. CONCLUSION Dabigatran may therefore decrease the severity of ischemic stroke, even if ischemic stroke occurs.

Clinical Review of 28 Patients with Basilar Artery Occlusion

BACKGROUND We retrospectively analyzed factors related to the outcomes of patients with basilar artery occlusion. METHODS Twenty-eight patients with basilar artery occlusion admitted to our hospital within 24 hours after onset between April 2007 and December 2010 were included. We investigated parameters related to outcome, such as coexisting disease, clinical type, clinical severity at admission, the site of occlusion and the infarction lesion, the collateral flow from posterior communicating artery, therapy, and time to therapy after onset. RESULTS Of 28 patients with basilar artery occlusion, good outcomes occurred in 6 patients (21%) and poor outcomes occurred in 22 patients (79%). Clinical severity on admission was significantly different between the 2 groups. Three of 5 patients with percutaneous transluminal angioplasty achieved recanalization. Two of 3 cases with recanalization resulted in poor outcomes. CONCLUSIONS Clinical severity on admission was the determinant factor of functional prognosis in patients with basilar artery occlusion.