Moon Ku Han

Impact of neurological and medical complications on 3‐month outcomes in acute ischaemic stroke

Objective:  To evaluate the impact of neurological and medical complications on 3‐month outcomes in acute ischaemic stroke patients.

Case Characteristics, Hyperacute Treatment, and Outcome Information from the Clinical Research Center for Stroke-Fifth Division Registry in South Korea

Characteristics of stroke cases, acute stroke care, and outcomes after stroke differ according to geographical and cultural background. To provide epidemiological and clinical data on stroke care in South Korea, we analyzed a prospective multicenter clinical stroke registry, the Clinical Research Center for Stroke-Fifth Division (CRCS-5). Patients were 58% male with a mean age of 67.2±12.9 years and median National Institutes of Health Stroke Scale score of 3 [1-8] points. Over the 6 years of operation, temporal trends were documented including increasing utilization of recanalization treatment with shorter onset-to-arrival delay and decremental length of stay. Acute recanalization treatment was performed in 12.7% of cases with endovascular treatment utilized in 36%, but the proportion of endovascular recanalization varied across centers. Door-to-IV alteplase delay had a median of 45 [33-68] min. The rate of symptomatic hemorrhagic transformation (HT) was 7%, and that of any HT was 27% among recanalization-treated cases. Early neurological deterioration occurred in 15% of cases and were associated with longer length of stay and poorer 3-month outcomes. The proportion of mRS scores of 0-1 was 42% on discharge, 50% at 3 months, and 55% at 1 year after the index stroke. Recurrent stroke up to 1 year occurred in 4.5% of patients; the rate was higher among older individuals and those with neurologically severe deficits. The above findings will be compared with other Asian and US registry data in this article.

Is asymptomatic hemorrhagic transformation really innocuous

Objectives: Asymptomatic hemorrhagic transformation (HT) is not associated with immediate deterioration of patients with acute ischemic stroke. However, it is unclear whether it is clinically innocuous with respect to long-term outcome. The aim of this study was to determine the impact of asymptomatic HT on 3-month outcome. Methods: A consecutive series of 1,618 patients, hospitalized between January 2004 and August 2007 for ischemic stroke within 7 days from symptom onset were identified in a prospective stroke registry database. Those who had no evidence of acute cerebral ischemia on diffusion-weighted MRI, who did not undergo T2-weighted gradient echo MRI, whose modified Rankin Scale (mRS) score at 3 months after stroke onset was not available, or who had symptomatic HT were excluded. The odds ratio (OR) of asymptomatic HT was calculated for the full distribution of mRS score and adjusted for variables with p < 0.25 with respect to their associations with asymptomatic HT or functional outcome. Results: Of 1,412 patients eligible for the study, 100 (7.1%) had asymptomatic HT. Patients who experienced asymptomatic HT were more likely to have cardioembolic stroke, to receive thrombolytic therapy, to receive anticoagulation with heparin, and to have a higher initial NIH Stroke Scale score. The crude and adjusted ORs of asymptomatic HT for an increment of mRS score at 3 months were 2.94 (95% confidence interval 2.05–4.24) and 1.90 (1.27–2.82), respectively. Conclusions: Our study shows that the odds of a worse outcome are increased by a factor of 2 in patients with asymptomatic HT compared with those without HT after acute ischemic stroke.

A new high-performance poly-Si TFT by simple excimer laser annealing on selectively floating a-Si layer

A new poly-Si TFT with a single grain-boundary has been fabricated by a simple ELA method which employs a selectively floating a-Si active layer. A thermally insulating air-gap between the floating a-Si and substrate successfully induces the lateral grain growth. Large lateral grains exceeding 4 /spl mu/m have been grown by a single laser irradiation with wide ELA process window. The proposed poly-Si TFT exhibits high mobility of 331 cm/sup 2//V sec due to the high-quality grains.

A retrieval thrombectomy technique with the Solitaire stent in a large cerebral artery occlusion

BackgroundTo describe preliminary experiences and the procedural details of retrieval thrombectomy using a self-expanding and fully retrievable Solitaire stent (ev 3 Inc., CA, USA) in acute ischemic stroke (AIS) patients with large artery occlusions.MethodsEight patients with AIS were treated by mechanical thrombectomy using a self-expanding, fully retrievable stent (Solitaire, ev 3 Inc., CA, USA). The stent was deployed to cover the whole intra-arterial clot and then it was slowly retrieved while occluding the internal cerebral artery (ICA) with a balloon guiding catheter. Additionally, continuous negative pressure was applied through the balloon guiding catheter with a specially designed gun device. Occlusion sites were M1 in six cases including one combined supraclinoid ICA occlusion and the other combined M2 occlusion, M2 in 1 case and one basilar artery top.ResultsComplete recanalization was achieved in all patients. Procedure time was 45 min or less in seven cases and 70 min in one case. Distal emboli occurred in one case in which the balloon guide catheter was not used. Only in this case was intraarterial fibrinolytics infusion necessary. There was no post-operative intracranial hemorrhage.ConclusionsIn our experience, retrieval thrombectomy with the Solitaire stent was a simple and effective method for reopening large cerebral arteries in AIS patients.

Effect of blood pressure on 3-month functional outcome in the subacute stage of ischemic stroke

ABSTRACT Objective: We aimed to study various measures of blood pressure (BP) in the subacute phase of ischemic stroke to determine whether any of them predicted clinical outcome. Methods: In this retrospective observational study, a consecutive series of patients hospitalized for ischemic stroke within 48 hours of onset were enrolled. The subacute stage of stroke was defined as the time period from 72 hours of symptom onset to discharge or transfer. During this period, mean, maximum, maximum − minimum, SD, and coefficient of variation of systolic BP (SBP) and diastolic BP (DBP) were determined. A baseline severity-adjusted analysis was performed using each patient’s 3-month modified Rankin Scale score as the primary outcome. Results: Among a total of 2,271 patients, the median number of BP measurements was 34 per person and the median interval from onset to discharge was 8.7 days. Measures of variability of BP were associated with poor outcome. One SD increase of maximum − minimum (odds ratio [OR], 1.26; 95% confidence interval [CI], 1.12–1.42), SD (OR, 1.20; 95% CI, 1.07–1.34), or coefficient of variation (OR, 1.21; 95% CI, 1.09–1.35) for SBP, but not mean level of SBP (OR, 0.92; 95% CI, 0.79–1.07), was independently associated with poor outcome. Results were similar for DBP. Conclusion: This study shows that variability of BP, but not average BP in the subacute stage of ischemic stroke, is associated with functional outcome at 3 months after stroke onset.

Analgesia before a spinal block for femoral neck fracture: fascia iliaca compartment block

Background: In this prospective randomized study, the authors compared the analgesic effect of a fascia iliaca compartment (FIC) block with that of intravenous (i.v.) alfentanil when administered to facilitate positioning for spinal anaesthesia in elderly patients undergoing surgery for a femoral neck fracture.

Prevalence study of proximal vertebral artery stenosis using high‐resolution contrast‐enhanced magnetic resonance angiography:

Purpose: To evaluate the prevalence of proximal vertebral artery stenosis, compared with those of the distal vertebral/basilar artery and extracranial internal carotid artery, in a large population of stroke and non‐stroke patients. Material and Methods: Nine‐hundred‐and‐thirty‐five patients who underwent high‐resolution contrast‐enhanced magnetic resonance angiography in a regional general hospital were categorized into six groups based on neurological symptoms and disease: an asymptomatic group (n = 182), a minor symptom group with headache or dizziness (n = 519), a cardiac group with coronary artery steno‐occlusive disease (n = 15), a hemorrhagic group with old cerebral hemorrhage (n = 26), an anterior circulation infarct group (n = 121), and posterior circulation infarct group (n = 72). Prevalence of stenosis of the proximal vertebral artery, distal vertebral/basilar artery, and internal carotid artery was analyzed. Results: The prevalence of stenosis of the proximal vertebral artery, distal vertebral/basilar artery, and internal carotid artery was 12.9%, 5.5%, and 7.2%, respectively, in the study population, and rose as the age increased (P<0.0001 for all arteries). The prevalence of stenosis of the proximal vertebral artery, distal vertebral/basilar artery, and internal carotid artery was 3.3%, 0.5%, and 1.1%, respectively, in the asymptomatic group; 8.3%, 2.1%, and 3.7%, respectively, in the minor symptom group; 13.3%, 6.7%, and 6.7%, respectively, in the cardiac group; 19.2%, 7.7%, and 7.7%, respectively, in the hemorrhagic group; 27.3%, 8.3%, and 25.6%, respectively, in the anterior circulation infarct group; and 44.4%, 36.1%, and 16.7%, respectively, in the posterior circulation infarct group. This increasing tendency of stenosis accordingly was statistically significant (P<0.0001 for all arteries). Conclusion: The prevalence of proximal vertebral artery stenosis was highest, compared with those of the distal vertebral/basilar artery and internal carotid artery, although the clinical significance of proximal vertebral artery stenosis should be investigated in further studies.

Low-Versus Standard-Dose Alteplase for Ischemic Strokes Within 4.5 Hours A Comparative Effectiveness and Safety Study

Background and Purpose— The low-dose (0.6 mg/kg) alteplase strategy to treat acute ischemic stroke patients became widespread in East Asian countries, without rigorous testing against standard-dose (0.9 mg/kg) alteplase treatment. Our aim was to investigate the comparative effectiveness and safety of the low-dose versus standard-dose intravenous alteplase strategy. Methods— A total of 1526 acute ischemic stroke patients who qualified for intravenous alteplase and treated within 4.5 hours were identified from a prospective, multicenter, and nationwide stroke registry database. Primary outcomes were a modified Rankin scale score of 0 to 1 at 3 months after stroke and occurrence of symptomatic hemorrhagic transformation. Inverse probability of low-dose alteplase weighting by propensity scores was used to remove baseline imbalances between the 2 groups, and variation among centers were also accounted using generalized linear mixed models with a random intercept. Results— Low-dose intravenous alteplase was given to 450 patients (29.5%) and standard-dose intravenous alteplase to 1076 patients (70.5%). Low-dose alteplase treatment was comparable to standard-dose therapy according to the following adjusted outcomes and odds ratios (95% confidence intervals): modified Rankin scale score 0 to 1 at 3 months and 0.95 (0.68–1.32); modified Rankin scale 0 to 2 at 3 months and 0.84 (0.62–1.15); symptomatic hemorrhagic transformation and 1.05 (0.65–1.70); and 3-month mortality and 0.54 (0.35–0.83). The associations were unchanged when the analysis was limited to those without endovascular recanalization. Conclusions— The low-dose alteplase strategy was comparable to the standard-dose treatment in terms of the effectiveness and safety.

The Occurrence of Warfarin-Related Nephropathy and Effects on Renal and Patient Outcomes in Korean Patients

Background Warfarin-related nephropathy (WRN) is a recently described disease entity, in which excessive warfarinization (international normalized ratio (INR) >3.0) causes acute kidney injury. Previous reports regarding WRN included few Asian patients who might have differed from the western WRN patients in terms of genetic and environmental factors. Methods During the period of March 2003 to December 2011, the data about a total of 1297 patients who had serum creatinine (sCr) level measured within 1 week after INR >3.0 and within 6 months before INR >3.0 was analyzed through the retrospective review of electronic medical records of a single tertiary hospital in Korea. Result WRN developed in 19.3% of patients having excessive warfarinization. The incidence was higher in the chronic kidney disease (CKD) group than the non-CKD group. The risk of WRN increased as the basal serum albumin level decreased and was strongly associated with highest quartile serum AST level at post INR elevation and the presence of congestive heart failure. But the presence of atrial fibrillation was protective against the development of WRN. Neither the presence of CKD nor basal estimated glomerular filtration rate (eGFR) was an independent risk factor for WRN. Despite no difference in the basal sCr level, the sCr level was higher in patients with WRN than those without WRN after follow-up. The mortality rates were also higher in patients with WRN. Conclusions WRN developed in 19.3% of patients having excessive warfarinization. A lower basal serum albumin, highest quartile serum AST level at post INR elevation, and congestive heart failure were associated with the occurrence of WRN. The development of WRN adversely affected renal and patient outcomes.