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Ji Hoe Heo

Publications and source records attributed to Ji Hoe Heo.

16 recordsLinked to original sources
PubMed2006

Improved time intervals by implementation of computerized physician order entry-based stroke team approach.

BACKGROUND: The need for rapid evaluation and treatment of acute stroke patients has been well documented. A computerized physician order entry (CPOE) system can improve communication and provide immediate access to information, which may be useful for an effective team approach program targeted to reduce in-hospital time delays. METHODS: To reduce the time from a patient's arrival at the emergency department to thrombolysis, a team approach program using CPOE was developed, and its efficacy was investigated by comparing time intervals from arrival to evaluation and intravenous tissue-type plasminogen activator (tPA) treatment before and after the implementation of the program. RESULTS: Among 379 consecutive patients who were screened as potential candidates for thrombolysis, 25 patients (6.6%) received tPA during a 1-year period after initiation of the program. Fourteen patients were treated with tPA in the previous year. After program implementation, time from arrival to computed tomography scan was reduced from 34 to 19 min (p = 0.01). Time to report of complete blood count was also shortened from 52 to 33 min (p < 0.01). Finally, time from arrival to tPA treatment was reduced by 23 min (from 79 to 56 min; p < 0.01). Onset-to-door time tended to be longer after the program implementation (from 41 to 60 min; p = 0.14). CONCLUSIONS: Implementation of the CPOE-based team approach program significantly reduced time from emergency department arrival to evaluations and treatment.

Acute Disease↗
PubMed2006

A new subtype classification of ischemic stroke based on treatment and etiologic mechanism.

A new subtype classification of ischemic stroke was developed to reflect recent therapeutic strategies as well as evolving concepts of stroke definitions and mechanisms. In 200 consecutive patients with acute ischemic stroke, the inter-rater reliability and proportion of subtypes of the new classification system were assessed and compared with those of the Trial of ORG 10172 in the Acute Stroke Treatment (TOAST) classification. The most frequent subtype of the new classification was atherothrombosis (n = 80, 40%), followed by stroke of undetermined etiology (n = 54, 27%), small artery disease (n = 33, 16.5%), cardioembolism (n = 26, 13%), and stroke of other determined etiology (n = 7, 3.5%). Three raters agreed to the stroke subtype diagnosis in 165 out of 200 cases and the overall kappa value was excellent (kappa = 0.82). The new classification system for brain infarction was easy to use and had high inter-rater reliability.

Adult↗
PubMed2006

Early recanalization after intravenous administration of recombinant tissue plasminogen activator as assessed by pre- and post-thrombolytic angiography in acute ischemic stroke patients.

BACKGROUND AND PURPOSE: Recanalization rates after the intravenous (IV) recombinant tissue plasminogen activator (rt-PA) treatment have been poorly studied in acute stroke. METHODS: CT angiography was performed before IV rt-PA in all patients and digital subtraction angiography was undertaken for intra-arterial thrombolysis in cases of no improvement after rt-PA infusion. RESULTS: Forty-five patients were treated with IV rt-PA. Initial CT angiography showed relevant arterial occlusions in 35 patients. Recanalization after rt-PA therapy was demonstrated by digital subtraction angiography in 7 of the 31 patients with the occlusion on initial CT angiography: 2/16 in the internal carotid or proximal middle cerebral artery, 3/11 in the distal middle cerebral artery and 2/4 in the basilar artery occlusion. CONCLUSIONS: The early recanalization rate after IV rt-PA use was very low in cases with large proximal arterial occlusions. CT angiography before IV rt-PA may be useful for the prediction of its efficacy.

Angiography, Digital Subtraction↗
PubMed2006

Predictive implications of recurrent transient ischemic attacks in large-artery atherosclerosis.

BACKGROUND: It is uncertain whether recurrent transient ischemic attacks (R-TIAs), when comparing with single TIAs (S-TIAs), have any distinct mechanisms. METHODS: All consecutive patients with TIAs, who had been admitted for a 2-year period, were divided into two groups: those who had R-TIAs and those who had S-TIAs. Registry data, medical records, and imaging findings were reviewed and compared between the two groups. RESULTS: There were 85 patients who had TIAs: 42 patients had R-TIAs, and 43 patients had S-TIAs. On univariate analysis, R-TIA patients had less cardiac embolic TIA sources, less weakness, less speech disturbances, shorter symptom duration, a longer time interval from onset to treatment, less abnormalities on diffusion-weighted magnetic resonance imaging, and more significant relevant arterial stenoses. After logistic regression analysis, independent factors associated with R-TIAs were symptom duration < 10 min (odds ratio OR 3.62; 95% confidence interval CI 1.37-9.57), > or = 50% stenosis of the clinically relevant artery (OR 7.08; 95% CI 1.29-38.71), and absence of cardiac embolic sources (OR 0.04; 95% CI 0.002-0.71). CONCLUSIONS: R-TIAs may have pathophysiological mechanisms distinct from those of S-TIAs and so may provide a clue for the etiologic diagnosis, in that patients with R-TIAs are more likely to have large-artery atherosclerosis.

Angiography, Digital Subtraction↗
PubMed2006

Paradoxically accelerated fatal brain herniation following thrombolytic therapy in acute ischemic stroke.

INTRODUCTION: The use of plasminogen activators (PAs) in acute stroke patients has dual effects. PAs are beneficial by dissolving thrombi occluding an artery, but may be harmful by their proteolytic and excitotoxic actions. METHODS AND RESULTS: We report two patients with a fatal brain herniation who rapidly deteriorated despite the successful recanalization and the sustained arterial patency or blood flow. Imaging studies taken after the thrombolytic treatment suggested early occurrence of cellular damage and profound breakdown of the blood-brain barrier. CONCLUSION: Fatal brain edema occurred after persistent reperfusion by the thrombolytic therapy. Paradoxical thrombolytic-induced injury, which has been suggested in experimental studies, might play a role.

Aged↗
PubMed2005

Detection of thrombus in acute ischemic stroke: value of thin-section noncontrast-computed tomography.

BACKGROUND AND PURPOSE: Previous studies on the hyperdense middle cerebral artery (MCA) sign were conducted using > or =5-mm thickness noncontrast-computed tomography (NCT). The purpose of this study was to compare thin-section NCT with 5-mm NCT in the detection of thrombus in acute ischemic stroke. METHODS: Enrolled were consecutive 51 patients with acute infarction in the anterior or MCA territory. All patients underwent both 5-mm NCT and either 1.25- or 1-mm thin-section helical NCT within 6 hours of symptom onset. Patients were assigned to either the single or multisegmental occlusion group, depending on the thrombus extent on thin-section NCT. Thin-section NCT and 5-mm NCT were compared in the detection of thrombi. RESULTS: Thrombi were identified in 45 patients (88%) on thin-section NCT and 16 on 5-mm NCT (31%; P<0.001). No occlusion was seen in 6 patients. Both sensitivity and specificity of thin-section NCT in detection of thrombus were 100%. CONCLUSIONS: Acute thrombus can be detected with higher sensitivity on thin-section NCT than on 5-mm NCT, and its extent is more accurately determined on thin-section NCT.

Aged↗
PubMed2005

Rescue localized intra-arterial thrombolysis for hyperacute MCA ischemic stroke patients after early non-responsive intravenous tissue plasminogen activator therapy.

The outcome of patients who show no early response to intravenous (i.v.) tissue plasminogen activator (tPA) therapy is poor. The objective of this study was to evaluate the feasibility of rescue localized intra-arterial thrombolysis (LIT) therapy for acute ischemic stroke patients after an early non-responsive i.v. tPA therapy. Patients with proximal MCA occlusions who were treated by LIT (n = 10) after failure of early response [no improvement or improvement of National Institute of Health Stroke Scale (NIHSS) scores of < or = 3] to i.v. tPA therapy (0.9 mg/kg-10% bolus and 90% i.v. infusion over 60 min) were selected. The recanalization rates, incidence of post-thrombolysis hemorrhage and clinical outcomes [baseline and discharge NIHSS scores, mortality, 3 months Barthel index (BI) and modified Rankin score (mRS)] were evaluated. Rescue LIT therapy was performed on ten MCA occlusion patients (male:female = 3:7, mean age 71 years). The mean time between the initiation of i.v. tPA therapy and the initiation of intra-arterial urokinase (i.a. UK) was 117+/-25.0 min [time to i.v. tPA 137+/-32 min; time to digital subtraction angiography (DSA) 221+/-42 min; time to i.a. UK 260+/-46 min]. The baseline NIHSS scores showed significant improvement at discharge (median from 18 to 6). Symptomatic hemorrhage and, consequent, mortality were noted in 2/10 (20%) patients. Three months good outcome was noted in 4/10 (40%, mRS 0-2) and 3/10 (30%, BI > or = 95). In conclusion, rescue LIT therapy can be considered as a treatment option for patients not showing early response to full dose i.v. tPA therapy. Larger scale studies for further validation of this protocol may be necessary.

Aged↗
PubMed2005

Free radicals as triggers of brain edema formation after stroke.

Brain edema is a leading cause of death after stroke. Cytotoxic edema, which is most severe in astrocytes, begins within a few minutes of adenosine triphosphate depletion and reflects the ultimate infarct size. Vasogenic edema is caused by uncontrolled fluid leakage from the blood to the brain parenchyma through a weakened blood-brain barrier (BBB) and contributes to an actual net volume increase of the brain, which often leads to death. Recent research on ischemia-induced injury mechanisms of the microvasculature has led to the disclosure of the mechanisms and cellular pathways leading to BBB breakdown. In addition, the introduction of magnetic resonance imaging to clinical practice has enabled the evaluation of edema severity in stroke patients and differentiation between cytotoxic and vasogenic edema. Free radicals exert their deleterious actions during both cytotoxic and vasogenic edema. They can contribute to BBB disruption directly and can also trigger molecular pathways related to the dysfunction of ion transporters in the cell membrane and those related to increased vascular permeability. The development of effective therapeutic strategies aimed at reducing brain edema based on targeting specific molecular pathways involved may reduce death and disability from stroke.

Blood-Brain Barrier↗
PubMed2005

The usefulness of fractional anisotropy maps in localization of lacunar infarctions in striatum, internal capsule and thalamus.

We aimed in this study to assess the clinical usefulness of fractional anisotropy (FA) maps in the evaluation of lacunar infarctions in striatum, internal capsule and thalamus. We retrospectively reviewed 28 patients (18 men, 10 women; mean age 63 years) who had acute lacunar infarction in striatum, internal capsule and thalamus on diffusion weighted MR imaging (DWI). Fractional anisotropy (FA) maps were generated in addition to conventional T2 weighted images (T2WI) and trace maps of DWI. Two radiologists reviewed the location of infarcts in combination with and without FA maps. Exact location of infarction was determined by FA maps, i.e. on the white band of internal capsule or outside the internal capsule. Accuracy and inter-observer agreement on determination of the location of infarction was evaluated. Accuracy of infarct localization by T2WI-DWI only was varied from 72 to 91% according to the observers. Inter-observer agreement value was moderate (Kappa=0.446), when images were interpreted by T2WI-DWI only. Clinical manifestation of each lesions were varied, but sensory motor stroke was mainly observed in thalamic lesion (50%), while pure motor hemiparesis was predominant in the case of infarct involving internal capsule, corona radiata (91%) and basal ganglia (83%). The FA map is useful in the evaluation of lacunar lesions in striatum, internal capsule and thalamus. Clinical presentation varies according to the exact location of lacunar infarctions, and more accurate diagnosis can be made by FA maps as well as conventional T2-weighted image and DWI.

Acute Disease↗
PubMed2004

Persistent increase of matrix metalloproteinases in cerebrospinal fluid of tuberculous meningitis.

Matrix metalloproteinase (MMP)-2 and MMP-9 were analyzed by gelatin zymography and an enzyme-linked immunosorbent assay (ELISA) in a cerebrospinal fluid (CSF) from patients with tuberculous meningitis (n=24), acute aseptic meningitis (n=23) and the control (n=10). The MMP-2 and MMP-9 levels were significantly higher in the samples from the tuberculous meningitis patients than those from either the aseptic meningitis patients or the controls. In tuberculous meningitis, the patients with late neurologic complications had higher MMP-2 and MMP-9 levels than those without. The persistent increase in the MMP-2 and MMP-9 levels was associated with the development of complications following tuberculous meningitis. Inhibiting the MMPs may be an effective strategy for preventing or reducing the complications in tuberculous meningitis.

Electrophoresis, Polyacrylamide Gel↗
PubMed2004

Vestibular imbalance associated with a lesion in the nucleus prepositus hypoglossi area.

BACKGROUND: The nucleus prepositus hypoglossi (NPH) is known to be a neural integrator of horizontal eye movements. Although the role of the human NPH is not well known, it may also function in postural balance, in view of its anatomic connections with the vestibular nuclei and vestibulocerebellum and of lesion studies in experimental animals. OBJECTIVE: To show that the human NPH contributes to vestibular function in addition to eye movement control. DESIGN: Case series. SETTING: University hospital. Patients Six patients with small and discrete brainstem infarctions that predominantly involved the NPH region.Main Outcome Measure Findings on magnetic resonance images. RESULTS: The NPH was affected at the lower pontine level in 2 patients and at the upper medullary level in 4. In addition to gaze-evoked nystagmus, all patients had vertigo, vomiting, and postural ataxia, suggesting vestibular dysfunction. The patients typically fell contralaterally or bilaterally to the lesion side. CONCLUSION: The NPH serves a vestibular function in addition to its oculomotor control function.

Aged↗
PubMed2004

Sequential combination of intravenous recombinant tissue plasminogen activator and intra-arterial urokinase in acute ischemic stroke.

BACKGROUND AND PURPOSE: Combined intravenous (IV) and intra-arterial (IA) thrombolytic therapy may be faster and easier to initiate than monotherapy, and its recanalization rate may be better as well. The sequential combination of recombinant tissue plasminogen activator (rTPA) and urokinase (UK) has synergistic and complementary effects on clot lysis. We prospectively evaluated the effectiveness and safety of sequential combination of IV rTPA and IA UK in acute ischemic stroke. METHODS: IV rTPA was administered to patients with acute stroke within 3 hours of onset. Those whose condition had not improved at the end of rTPA infusion were further treated with selective IA UK. We evaluated baseline and 30-day National Institutes of Health Stroke Scale (NIHSS) scores and 90-day modified Rankin Scale scores. RESULTS: Thirty patients were initially treated with IV rTPA; 24 were further treated with IA UK. Four patients who had rapid reocclusion following initial successful IA therapy received IV abciximab. Fourteen of 24 patients who underwent angiography had an effective perfusion state of Thrombolysis in Myocardial Infarction grade 3 flow. Median baseline and 30-day NIHSS scores were 18 and 2, respectively. Eighteen patients improved to a modified Rankin scale score of 0 or 1 after 90 days. Symptomatic hemorrhage developed in two patients. CONCLUSION: The strategy of using conventional-dose IV rTPA and the sequential combination of IA UK in patients without an early clinical response to IV treatment was safe and feasible. This strategy achieved high complete arterial recanalization rates and good functional outcomes.

Abciximab↗
PubMed2003

Immediate reocclusion following a successful thrombolysis in acute stroke: a pilot study.

Immediate reocclusion after successful thrombolysis was angiographically examined in 29 consecutive stroke patients. The reocclusion, which was associated with a high-grade residual stenosis of initially perfused arteries, occurred in four patients. IV abciximab successfully dissolved the thrombus in all four patients. Rapid thrombotic reocclusion after successful thrombolysis is commonly observed in patients after an acute stroke. Administration of abciximab may lead to reperfusion of the reoccluded artery.

Abciximab↗
PubMed2003

Increase in plasma matrix metalloproteinase-9 in acute stroke patients with thrombolysis failure.

BACKGROUND AND PURPOSE: Platelet-rich thrombi are resistant to thrombolytics. Matrix metalloproteinases (MMPs) may be involved in platelet aggregation and contribute to thrombolysis failure in stroke patients. METHODS: Plasma samples from 23 stroke patients who had received thrombolytics and from 47 healthy volunteers were examined for MMP-2 and MMP-9 by both enzyme-linked immunosorbent assays and zymography. RESULTS: The arteries were recanalized in 15 patients but not in the other 8. The MMP-9 plasma level was significantly higher in patients whose arteries were not recanalized. CONCLUSIONS: MMP-9 may be associated with the formation of a thrombolytics-resistant thrombus.

Acute Disease↗
PubMed2002

Middle cerebral artery stenosis is a major clinical determinant in striatocapsular small, deep infarction.

BACKGROUND: The significance of the stenotic lesions of the middle cerebral artery (MCA) in Asian patients with striatocapsular small, deep infarctions (SSDIs) remains undetermined. OBJECTIVES: To investigate the frequency of stenotic lesions of the MCA in patients with SSDIs and to evaluate clinical and radiological features in those same patients. SETTING: Acute stroke registry of a university hospital. PATIENTS AND METHODS: One hundred two Korean patients with acute symptomatic SSDIs underwent cerebral angiography or magnetic resonance angiography and echocardiography. We divided these patients into 2 groups-patients with and without MCA occlusive lesions. The clinical and magnetic resonance image features were compared between these 2 groups. RESULTS: Thirty-seven patients (36%) had an ipsilateral proximal MCA lesion, whereas 65 patients (64%) showed no MCA abnormality on cerebral angiography or magnetic resonance angiography. Among 65 patients without an MCA lesion, 18 had an embolic source; the remaining 37 patients had no demonstrable embolic source. There were significant differences in the temporal profile and magnetic resonance imaging findings between the groups. Although the type of lacunar syndrome and the volume of infarcts did not differ between the groups, the unstable temporal profile and magnetic resonance imaging findings of multiple small infarcts in the symptomatic hemisphere were frequently observed in patients with MCA lesions. CONCLUSIONS: The proximal MCA lesion was a common cause of SSDIs in Korean patients. Depending on the existence of an MCA lesion, the clinical course and magnetic resonance imaging feature of the patients with SSDIs were different.

Acute Disease↗