Quality of Acute Stroke Care within Emergency Medical Service System in Korea: Proposal for Severe Emergency Medical Center

Background@#Korea recently established 70 emergency medical service areas. However, there are many concerns that medical resources for stroke could not be evenly distributed through the country. We aimed to compare the treatment quality and outcomes of acute stroke among the emergency medical service areas. @*Methods@#This study analyzed the data of 28,800 patients admitted in 248 hospitals which participated in the 8th acute stroke quality assessment by Health Insurance Review and Assessment Service. Individual hospitals were regrouped into emergency service areas according to the address of the location. Assessment indicators and fatality were compared by the service areas. We defined the appropriate hospital by the performance of intravenous thrombolysis. @*Results@#In seven service areas, there were no hospitals which received more than 10 stroke patients for 6 months. In nine service areas, there were no patients who underwent intravenous thrombolysis (IVT). Among 167 designated emergency medical centers, 50 hospitals (29.9%) responded that IVT was impossible 24 hours a day. There are 97 (39.1%) hospitals that meet the definitions of appropriate hospital. In 23 service areas (32.9%) had no appropriate or feasible hospitals. The fatality of service areas with stroke centers were 6.9% within 30 days and 15.6% within 1 year from stroke onset than those without stroke centers (7.7%, 16.9%, respectively). @*Conclusions@#There was a wide regional gap in the medical resource and the quality of treatments for acute stroke among emergency medical service areas in Korea. The poststroke fatality rate of the service areas which have stroke centers or appropriate hospitals were significantly low.

Comparison of Programmed Cell Death Ligand 1Status between Core Needle Biopsy and Surgical Specimens of Triple-Negative Breast Cancer

Purpose@#Pembrolizumab is currently used to treat advanced triple-negative breast cancer (TNBC) and high-risk early TNBC with neoadjuvant chemotherapy (NAC). The tumor-infiltrating lymphocyte (TIL) level and programmed cell death ligand 1 (PDL1) status are predictors of response to NAC and immune checkpoint inhibitor treatment. We aimed to investigate whether the PD-L1 status in core needle biopsies (CNBs) could represent the whole tumor in TNBC. @*Materials and Methods@#A total of 49 patients diagnosed with TNBC who received upfront surgery without NAC between January 2018 and March 2021 were included. The PD-L1 expression (SP142 and 22C3 clones) and TIL were evaluated in paired CNBs and resected specimens. The concordance PD-L1 status and TIL levels between CNBs and resected specimens were analyzed. @*Results@#PD-L1 positivity was more frequently observed in resected specimens. The overall reliability of TIL level in the CNB was good [intraclass correlation coefficient (ICC)=0.847, p<0.001]. The agreements of PD-L1 status were good and fair, respectively (SP142, κ=0.503, p<0.001; 22C3, κ=0.380, p=0.010). As the core number of CNB increased, the reliability and agreement also improved, especially from five tumor cores (TIL, ICC=0.911, p<0.001; PD-L1 [22C3], κ=0.750, p=0.028). Regarding PD-L1 (SP142), no further improvement was observed with ≥5 tumor cores (κ=0.600, p=0.058). @*Conclusion@#CNBs with ≥5 tumor cores were sufficient to represent the TIL level and PD-L1 (22C3) status in TNBC.

Safety and Efficacy of Intravenous Thrombolysis in the 3- to 4.5-hour Window in Acute Ischemic Stroke Patients Who Have Both Diabetes Mellitus and History of Prior Stroke

Background@#For acute ischemic stroke (AIS) patients with history of prior stroke (PS) and diabetes mellitus (DM), intravenous recombinant tissue plasminogen activator (IV-tPA) therapy in the 3- to 4.5-hour window is off-label in Korea. This study aimed to assess the safety and efficacy of IV-tPA in these patients. @*Methods@#Using data from a prospective multicenter stroke registry between January 2009 and March 2021, we identified AIS patients who received IV-tPA in the 3- to 4.5-hour window, and compared the outcomes of symptomatic intracranial hemorrhage (SICH), 3-month mortality, 3-month modified Rankin Scale (mRS) score 0-1 and 3-month mRS distribution between patients with both PS and DM (PS/DM, n=56) versus those with neither PS nor DM, or with only one (non-PS/DM, n=927). @*Results@#The PS/DM group versus the non-PS/DM group was more likely to have a prior disability, hypertension, hyperlipidemia, coronary heart disease and less likely to have atrial fibrillation. The PS/DM and the non-PS/DM groups had comparable rates of SICH (0% vs. 1.7%; p>0.999) and 3-month mortality (10.7% vs. 10.2%; p=0.9112). The rate of 3-month mRS 0-1 was non-significantly lower in the PS/DM group than in the non-PS/DM group (30.4% vs. 40.7%; adjusted odds ratio [95% confidence interval], 0.81 [0.41-1.59]). @*Conclusions@#In the 3- to 4.5-hour window, AIS patients with PS/DM, as compared to those with non-PS/DM, might benefit less from IV-tPA. However, given the similar risks of SICH and mortality, IV-tPA in the late time window could be considered in patients with both PS and DM.

Annual Endovascular Thrombectomy Case Volume and Thrombectomy-capable Hospitals of Korea in Acute Stroke Care / 예방의학회지

Objectives@#Although it is difficult to define the quality of stroke care, acute ischemic stroke (AIS) patients with moderate-to-severe neurological deficits may benefit from thrombectomy-capable hospitals (TCHs) that have a stroke unit, stroke specialists, and a substantial endovascular thrombectomy (EVT) case volume. @*Methods@#From national audit data collected between 2013 and 2016, potential EVT candidates arriving within 24 hours with a baseline National Institutes of Health Stroke Scale score ≥6 were identified. Hospitals were classified as TCHs (≥15 EVT case/y, stroke unit, and stroke specialists), primary stroke hospitals (PSHs) without EVT (PSHs-without-EVT, 0 case/y), and PSHs-with-EVT. Thirty-day and 1-year case-fatality rates (CFRs) were analyzed using random intercept multilevel logistic regression. @*Results@#Out of 35 004 AIS patients, 7954 (22.7%) EVT candidates were included in this study. The average 30-day CFR was 16.3% in PSHs-without-EVT, 14.8% in PSHs-with-EVT, and 11.0% in TCHs. The average 1-year CFR was 37.5% in PSHs-without-EVT, 31.3% in PSHs-with-EVT, and 26.2% in TCHs. In TCHs, a significant reduction was not found in the 30-day CFR (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.76 to 1.12), but was found in the 1-year CFR (OR, 0.84; 95% CI, 0.73 to 0.96). @*Conclusions@#The 1-year CFR was significantly reduced when EVT candidates were treated at TCHs. TCHs are not defined based solely on the number of EVTs, but also based on the presence of a stroke unit and stroke specialists. This supports the need for TCH certification in Korea and suggests that annual EVT case volume could be used to qualify TCHs.

Interactive Direct Interhospital Transfer Network System for Acute Stroke in South Korea

Background@#and PurposeInterhospital transfer is an essential practical component of regional stroke care systems. To establish an effective stroke transfer network in South Korea, an interactive transfer system was constructed, and its workflow metrics were observed. @*Methods@#In March 2019, a direct transfer system between primary stroke hospitals (PSHs) and comprehensive regional stroke centers (CSCs) was established to standardize the clinical pathway of imaging, recanalization therapy, transfer decisions, and exclusive transfer linkage systems in the two types of centers. In an active case, the time metrics from arrival at PSH (“door”) to imaging was measured, and intravenous thrombolysis (IVT) and endovascular treatment (EVT) were used to assess the differences in clinical situations. @*Results@#The direct transfer system was used by 27 patients. They stayed at the PSH for a median duration of 72 min (interquartile range [IQR], 38–114 min), with a median times of 15 and 58 min for imaging and subsequent processing, respectively. The door-to-needle median times of subjects treated with IVT at PSHs (n=5) and CSCs (n=2) were 21 min (IQR, 20.0–22.0 min) and 137.5 min (IQR, 125.3–149.8 min), respectively. EVT was performed on seven subjects (25.9%) at CSCs, which took a median duration of 175 min; 77 min at the PSH, 48 min for transportation, and 50 min at the CSC. Before EVT, bridging IVT at the PSH did not significantly affect the door-to-puncture time (127 min vs. 143.5 min, p=0.86). @*Conclusions@#The direct and interactive transfer system is feasible in real-world practice in South Korea and presents merits in reducing the treatment delay by sharing information during transfer.

Risk of Subsequent Events in Patients With Minor Ischemic Stroke or HighRisk Transient Ischemic Attack

This study aimed to present the prognosis after minor acute ischemic stroke (AIS) or transient ischemic attack (TIA), using a definition of subsequent stroke in accordance with recent clinical trials. In total, 9,506 patients with minor AIS (National Institutes of Health Stroke Scale ≤ 5) or high-risk TIA (acute lesions or ≥ 50% cerebral artery steno-occlusion) admitted between November 2010 and October 2013 were included. The primary outcome was the composite of stroke (progression of initial event or a subsequent event) and all-cause mortality. The cumulative incidence of stroke or death was 11.2% at 1 month, 13.3% at 3 months and 16.7% at 1 year. Incidence rate of stroke or death in the first month was 12.5 per 100 person-months: highest in patients with large artery atherosclerosis (17.0). The risk of subsequent events shortly after a minor AIS or high-risk TIA was substantial, particularly in patients with large artery atherosclerosis.

2022 Update of the Korean Clinical Practice Guidelines for Stroke: Antithrombotic Therapy for Patients with Acute Ischemic Stroke or Transient Ischemic Attack / 대한뇌졸중학회지

Antithrombotic therapy is a cornerstone of acute ischemic stroke (AIS) management and secondary stroke prevention. Since the first version of the Korean Clinical Practice Guideline (CPG) for stroke was issued in 2009, significant progress has been made in antithrombotic therapy for patients with AIS, including dual antiplatelet therapy in acute minor ischemic stroke or high-risk transient ischemic stroke and early oral anticoagulation in AIS with atrial fibrillation. The evidence is widely accepted by stroke experts and has changed clinical practice. Accordingly, the CPG Committee of the Korean Stroke Society (KSS) decided to update the Korean Stroke CPG for antithrombotic therapy for AIS. The writing members of the CPG committee of the KSS reviewed recent evidence, including clinical trials and relevant literature, and revised recommendations. A total of 35 experts were invited from the KSS to reach a consensus on the revised recommendations. The current guideline update aims to assist healthcare providers in making well-informed decisions and improving the quality of acute stroke care. However, the ultimate treatment decision should be made using a holistic approach, considering the specific medical conditions of individual patients.

Fasting and Non-Fasting Triglycerides in Patients With Acute Ischemic Stroke

Background@#Clinical implications of elevated fasting triglycerides (FTGs) and non-fasting triglycerides (NFTGs) in acute ischemic stroke (AIS) remain unknown. We aimed to elucidate the correlation and clinical significance of FTG and NFTG levels in AIS patients. @*Methods@#Using a multicenter prospective stroke registry, we identified AIS patients hospitalized within 24 hours of onset with available NFTG results. The primary outcome was a composite of stroke recurrence, myocardial infarction, and all-cause mortality up to one year. @*Results@#This study analyzed 2,176 patients. The prevalence of fasting and non-fasting hypertriglyceridemia was 11.5% and 24.6%, respectively. Multivariate analysis revealed that younger age, diabetes, higher body mass index and initial systolic blood pressure were independently associated with both fasting and non-fasting hypertriglyceridemia (all P < 0.05). Patients with higher quartiles of NFTG were more likely to be male, younger, eversmokers, diabetic, and have family histories of premature coronary heart disease and stroke (all P < 0.05). Similar tendencies were observed for FTG. The composite outcome was not associated with FTG or NFTG quartiles. @*Conclusion@#The fasting and non-fasting hypertriglyceridemia were prevalent in AIS patients and showed similar clinical characteristics and outcomes. High FTG and NFTG levels were not associated with occurrence of subsequent clinical events up to one year.

Effect of Transport Time on the Use of Reperfusion Therapy for Patients with Acute Ischemic Stroke in Korea

Background@#We investigated the association between geographic proximity to hospitals and the administration rate of reperfusion therapy for acute ischemic stroke. @*Methods@#We identified patients with acute ischemic stroke who visited the hospital within 12 hours of symptom onset from a prospective nationwide multicenter stroke registry. Reperfusion therapy was classified as intravenous thrombolysis (IVT), endovascular therapy (EVT), or combined therapy. The association between the proportion of patients who were treated with reperfusion therapy and the ground transport time was evaluated using a spline regression analysis adjusted for patient-level characteristics. We also estimated the proportion of Korean population that lived within each 30-minute incremental service area from 67 stroke centers accredited by the Korean Stroke Society. @*Results@#Of 12,172 patients (mean age, 68 ± 13 years; men, 59.7%) who met the eligibility criteria, 96.5% lived within 90 minutes of ground transport time from the admitting hospital. The proportion of patients treated with IVT decreased significantly when stroke patients lived beyond 90 minutes of the transport time (P = 0.006). The proportion treated with EVT also showed a similar trend with the transport time. Based on the residential area, 98.4% of Korean population was accessible to 67 stroke centers within 90 minutes. @*Conclusion@#The use of reperfusion therapy for acute stroke decreased when patients lived beyond 90 minutes of the ground transport time from the hospital. More than 95% of the South Korean population was accessible to 67 stroke centers within 90 minutes of the ground transport time.

Delayed Lesions on Diffusion-Weighted Imaging in Initially Lesion-Negative Stroke Patients / 대한뇌졸중학회지

Background@#and Purpose Lesions on diffusion-weighted imaging (DWI) occasionally appear on follow-up magnetic resonance imaging (MRI) among initially DWI-negative but clinically suspicious stroke patients. We established the prevalence of positive conversion in DWI-negative stroke and determined the clinical factors associated with it. @*Methods@#This retrospective, observational, single-center study included 5,271 patients hospitalized due to stroke/transient ischemic attack (TIA) in a single university hospital during 2010 to 2017. Patients without initial DWI lesions underwent follow-up DWI imaging as a routine practice. Adjusted hazard ratios (aHRs) for recurrent stroke risk according to positive conversion were determined using Cox proportional hazard regression. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for positive conversion among initially DWI-negative patients were estimated. @*Results@#In total, 694 (13.2%) patients (mean±standard deviation age, 62.9±13.7 years; male, 404 [58.2%]) were initially DWI-negative. Among them, 22.5% had positive-conversion on follow-up DWI. Positive conversion was associated with a higher risk of recurrent stroke (aHR, 3.12; 95% CI, 1.56 to 6.26). Early neurologic deterioration (aOR, 15.1; 95% CI, 5.71 to 47.66), atrial fibrillation (aOR, 6.17; 95% CI, 3.23 to 12.01), smoking (aOR, 3.76; 95% CI, 2.19 to 6.63), pre-stroke dependency (aOR, 1.62; 95% CI, 1.15 to 2.27), objective hemiparesis (aOR, 4.39; 95% CI, 1.90 to 10.32), longer symptom duration (aOR, 2.17; 95% CI, 1.57 to 3.08), high cholesterol (aOR, 4.70; 95% CI, 1.78 to 12.77), National Institutes of Health Stroke Scale score (aOR, 1.44; 95% CI, 1.08 to 1.91), and high systolic blood pressure (aOR, 1.01; 95% CI, 1.00 to 1.02) were associated with a higher incidence of lesions with delayed appearance. Regarding the location of lesions on follow-up DWI, 34.6% and 21.2% were in the cortex and brainstem, respectively. @*Conclusions@#In DWI-negative stroke/TIA, positive conversion is associated with a higher risk of recurrent stroke. DWI-negative stroke with factors related to positive conversion may require follow-up MRI for a definitive diagnosis.

Fimasartan-Based Blood Pressure Control after Acute Cerebral Ischemia: The Fimasartan-Based Blood Pressure Control after Acute Cerebral Ischemia Study

Background@#and Purpose: Blood pressure (BP) control is strongly recommended, but BP control rate has not been well studied in patients with stroke. We evaluated the BP control rate with fimasartan-based antihypertensive therapy initiated in patients with recent cerebral ischemia. @*Methods@#This multicenter, prospective, single-arm trial involved 27 centers in South Korea. Key inclusion criteria were recent cerebral ischemia within 90 days and high BP [systolic blood pressure (SBP) >140 mm Hg or diastolic blood pressure (DBP) >90 mm Hg]. BP lowering was initiated with fimasartan. BP management during the follow-up was at the discretion of the responsible investigators. The primary endpoint was the target BP goal achievement rate (<140/90 mm Hg) at 24 weeks. Key secondary endpoints included achieved BP and BP changes at each visit, and clinical events (ClinicalTrials.gov Identifier: NCT03231293). @*Results@#Of 1,035 patients enrolled, 1,026 were included in the safety analysis, and 951 in the efficacy analysis. Their mean age was 64.1 years, 33% were female, the median time interval from onset to enrollment was 10 days, and the baseline SBP and DBP were 162.3±16.0 and 92.2±12.4 mm Hg (mean±SD). During the study period, 55.5% of patients were maintained on fimasartan monotherapy, and 44.5% received antihypertensive therapies other than fimasartan monotherapy at at least one visit. The target BP goal achievement rate at 24-week was 67.3% (48.6% at 4-week and 61.4% at 12-week). The mean BP was 139.0/81.8±18.3/11.7, 133.8/79.2±16.4/11.0, and 132.8/78.5±15.6/10.9 mm Hg at 4-, 12-, and 24-week. The treatment-emergent adverse event rate was 5.4%, including one serious adverse event. @*Conclusions@#Fimasartan-based BP lowering achieved the target BP in two-thirds of patients at 24 weeks, and was generally well tolerated.

Left Atrial Diameter and Atrial Ectopic Burden in Patients with Embolic Stroke of Undetermined Source:Risk Stratification of Atrial Fibrillation with Insertable Cardiac Monitor Analysis

Background@#and Purpose An insertable cardiac monitor (ICM) has been demonstrated to be a useful tool for detecting subclinical atrial fibrillation (AF) in patients with embolic stroke of undetermined source (ESUS). This study aimed to identify the clinical predictors of AF in ESUS patients with ICMs. @*Methods@#We retrospectively selected consecutive patients with an ICM implanted for AF detection following ESUS. The primary endpoint was defined as any AF episode lasting for longer than 5 min. The atrial ectopic burden (AEB) was calculated as the percentage of the number of conducted QRS from atrial ectopy on Holter monitoring. @*Results@#This study included 136 patients. AF lasting ≥5 min was detected in 20 patients (14.7%) during a median follow-up period of 6.6 months (interquartile range, 3.3–10.8 months).AF patients had a higher AEB (0.20% vs. 0.02%,p<0.001) and a larger left atrial diameter (LAD, 41.0 mm vs. 35.3 mm, p<0.001) than those without AF. The areas under the receiver operating characteristic curves were 0.795 and 0.816 for the LAD and log-transformed AEB, respectively, for the best cutoff values of 38.5 mm for LAD and 0.050% for AEB. AF lasting ≥5 min was detected in 34.6% (9/26) of patients with LAD ≥38.5 mm and AEB ≥0.050%, and in 0% (0/65) of those with LAD <38.5 mm and AEB <0.050%. @*Conclusions@#AF was detected in a significant proportion of ESUS patients during a 6.6-month follow-up. The LAD and AEB are good predictors of AF and might be useful for AF risk stratification in ESUS patients.

Fimasartan-Based Blood Pressure Control after Acute Cerebral Ischemia: The Fimasartan-Based Blood Pressure Control after Acute Cerebral Ischemia Study

Background@#and Purpose: Blood pressure (BP) control is strongly recommended, but BP control rate has not been well studied in patients with stroke. We evaluated the BP control rate with fimasartan-based antihypertensive therapy initiated in patients with recent cerebral ischemia. @*Methods@#This multicenter, prospective, single-arm trial involved 27 centers in South Korea. Key inclusion criteria were recent cerebral ischemia within 90 days and high BP [systolic blood pressure (SBP) >140 mm Hg or diastolic blood pressure (DBP) >90 mm Hg]. BP lowering was initiated with fimasartan. BP management during the follow-up was at the discretion of the responsible investigators. The primary endpoint was the target BP goal achievement rate (<140/90 mm Hg) at 24 weeks. Key secondary endpoints included achieved BP and BP changes at each visit, and clinical events (ClinicalTrials.gov Identifier: NCT03231293). @*Results@#Of 1,035 patients enrolled, 1,026 were included in the safety analysis, and 951 in the efficacy analysis. Their mean age was 64.1 years, 33% were female, the median time interval from onset to enrollment was 10 days, and the baseline SBP and DBP were 162.3±16.0 and 92.2±12.4 mm Hg (mean±SD). During the study period, 55.5% of patients were maintained on fimasartan monotherapy, and 44.5% received antihypertensive therapies other than fimasartan monotherapy at at least one visit. The target BP goal achievement rate at 24-week was 67.3% (48.6% at 4-week and 61.4% at 12-week). The mean BP was 139.0/81.8±18.3/11.7, 133.8/79.2±16.4/11.0, and 132.8/78.5±15.6/10.9 mm Hg at 4-, 12-, and 24-week. The treatment-emergent adverse event rate was 5.4%, including one serious adverse event. @*Conclusions@#Fimasartan-based BP lowering achieved the target BP in two-thirds of patients at 24 weeks, and was generally well tolerated.

Left Atrial Diameter and Atrial Ectopic Burden in Patients with Embolic Stroke of Undetermined Source:Risk Stratification of Atrial Fibrillation with Insertable Cardiac Monitor Analysis

Background@#and Purpose An insertable cardiac monitor (ICM) has been demonstrated to be a useful tool for detecting subclinical atrial fibrillation (AF) in patients with embolic stroke of undetermined source (ESUS). This study aimed to identify the clinical predictors of AF in ESUS patients with ICMs. @*Methods@#We retrospectively selected consecutive patients with an ICM implanted for AF detection following ESUS. The primary endpoint was defined as any AF episode lasting for longer than 5 min. The atrial ectopic burden (AEB) was calculated as the percentage of the number of conducted QRS from atrial ectopy on Holter monitoring. @*Results@#This study included 136 patients. AF lasting ≥5 min was detected in 20 patients (14.7%) during a median follow-up period of 6.6 months (interquartile range, 3.3–10.8 months).AF patients had a higher AEB (0.20% vs. 0.02%,p<0.001) and a larger left atrial diameter (LAD, 41.0 mm vs. 35.3 mm, p<0.001) than those without AF. The areas under the receiver operating characteristic curves were 0.795 and 0.816 for the LAD and log-transformed AEB, respectively, for the best cutoff values of 38.5 mm for LAD and 0.050% for AEB. AF lasting ≥5 min was detected in 34.6% (9/26) of patients with LAD ≥38.5 mm and AEB ≥0.050%, and in 0% (0/65) of those with LAD <38.5 mm and AEB <0.050%. @*Conclusions@#AF was detected in a significant proportion of ESUS patients during a 6.6-month follow-up. The LAD and AEB are good predictors of AF and might be useful for AF risk stratification in ESUS patients.

Electrocardiographic Manifestations in Patients with COVID-19: Daegu in South Korea

Background and Objectives@#As the coronavirus disease 2019 (COVID-19) spreads worldwide, cardiac injury in patients infected with COVID-19 becomes a significant concern. Thus, this study investigates the impact of several electrocardiogram (ECG) parameters and disease severity in COVID-19 patients. @*Methods@#Seven medical centers in Daegu admitted 822 patients with COVID-19 between February and April 2020. This study examined 267 patients among them who underwent an ECG test and evaluated their biochemical parameters like C-reactive protein (CRP), log N-terminal pro-B-type Natriuretic Peptide (NT-proBNP), cardiac enzyme, and ECG parameters (heart rate, PR interval, QRS interval, T inversion, QT interval, and Tpe [the interval between peak to end in a T wave]). @*Results@#Those patients were divided into 3 groups of mild (100 patients), moderate (89 patients), and severe (78 patients) according to clinical severity score. The level of CRP, log NT-proBNP, and creatinine kinase-myocardial band were significantly increased in severe patients. Meanwhile, severe patients exhibited prolonged QT intervals (QTc) and Tpe (Tpe-c) compared to mild or moderate patients. Moreover, deceased patients (58; 21.7%) showed increased dispersion of QTc and Tpe-c compared with surviving patients (78.2±41.1 vs. 40.8±24.6 ms and 60.2±37.3 vs. 40.8±24.5 ms, both p<0.05, respectively). The QTc dispersion of more than 56.1 ms could predict the mortality in multivariate analysis (odd ratio, 11.55; 95% confidence interval, 3.746–42.306). @*Conclusions@#COVID-19 infections could involve cardiac injuries, especially cardiac repolarization abnormalities. A prolonged QTc dispersion could be an independent predictable factor of mortality.

Effect of Transport Time on the Use of Reperfusion Therapy for Patients with Acute Ischemic Stroke in Korea

Background@#We investigated the association between geographic proximity to hospitals and the administration rate of reperfusion therapy for acute ischemic stroke. @*Methods@#We identified patients with acute ischemic stroke who visited the hospital within 12 hours of symptom onset from a prospective nationwide multicenter stroke registry. Reperfusion therapy was classified as intravenous thrombolysis (IVT), endovascular therapy (EVT), or combined therapy. The association between the proportion of patients who were treated with reperfusion therapy and the ground transport time was evaluated using a spline regression analysis adjusted for patient-level characteristics. We also estimated the proportion of Korean population that lived within each 30-minute incremental service area from 67 stroke centers accredited by the Korean Stroke Society. @*Results@#Of 12,172 patients (mean age, 68 ± 13 years; men, 59.7%) who met the eligibility criteria, 96.5% lived within 90 minutes of ground transport time from the admitting hospital. The proportion of patients treated with IVT decreased significantly when stroke patients lived beyond 90 minutes of the transport time (P = 0.006). The proportion treated with EVT also showed a similar trend with the transport time. Based on the residential area, 98.4% of Korean population was accessible to 67 stroke centers within 90 minutes. @*Conclusion@#The use of reperfusion therapy for acute stroke decreased when patients lived beyond 90 minutes of the ground transport time from the hospital. More than 95% of the South Korean population was accessible to 67 stroke centers within 90 minutes of the ground transport time.

Electrocardiographic Manifestations in Patients with COVID-19: Daegu in South Korea

Background and Objectives@#As the coronavirus disease 2019 (COVID-19) spreads worldwide, cardiac injury in patients infected with COVID-19 becomes a significant concern. Thus, this study investigates the impact of several electrocardiogram (ECG) parameters and disease severity in COVID-19 patients. @*Methods@#Seven medical centers in Daegu admitted 822 patients with COVID-19 between February and April 2020. This study examined 267 patients among them who underwent an ECG test and evaluated their biochemical parameters like C-reactive protein (CRP), log N-terminal pro-B-type Natriuretic Peptide (NT-proBNP), cardiac enzyme, and ECG parameters (heart rate, PR interval, QRS interval, T inversion, QT interval, and Tpe [the interval between peak to end in a T wave]). @*Results@#Those patients were divided into 3 groups of mild (100 patients), moderate (89 patients), and severe (78 patients) according to clinical severity score. The level of CRP, log NT-proBNP, and creatinine kinase-myocardial band were significantly increased in severe patients. Meanwhile, severe patients exhibited prolonged QT intervals (QTc) and Tpe (Tpe-c) compared to mild or moderate patients. Moreover, deceased patients (58; 21.7%) showed increased dispersion of QTc and Tpe-c compared with surviving patients (78.2±41.1 vs. 40.8±24.6 ms and 60.2±37.3 vs. 40.8±24.5 ms, both p<0.05, respectively). The QTc dispersion of more than 56.1 ms could predict the mortality in multivariate analysis (odd ratio, 11.55; 95% confidence interval, 3.746–42.306). @*Conclusions@#COVID-19 infections could involve cardiac injuries, especially cardiac repolarization abnormalities. A prolonged QTc dispersion could be an independent predictable factor of mortality.

Routing to Endovascular Treatment of Ischemic Stroke in Korea: Recognition of Need for Process Improvement

Background@#To track triage, routing, and treatment status regarding access to endovascular treatment (EVT) after acute ischemic stroke (AIS) at a national level. @*Methods@#From national stroke audit data, potential candidates for EVT arriving within 6 hours with National Institute of Health Stroke Scale score of ≥ 7 were identified. Acute care hospitals were classified as thrombectomy-capable hospitals (TCHs, ≥ 15 EVT cases/year) or primary stroke hospital (PSH, < 15 cases/year), and patients' initial routes and subsequent inter-hospital transfer were described. Impact of initial routing to TCHs vs. PSHs on EVT and clinical outcomes were analyzed using multilevel generalized mixed effect models. @*Results@#Out of 14,902 AIS patients, 2,180 (14.6%) were EVT candidates. Eighty-one percent of EVT candidates were transported by ambulance, but only one-third were taken initially to TCHs. Initial routing to TCHs was associated with greater chances of receiving EVT compared to initial routing to PSHs (33.3% vs 12.1%, P < 0.001; adjusted odds ratio [aOR], 2.21; 95% confidence interval [CI], 1.59–2.92) and favorable outcome (38.5% vs. 28.2%, P < 0.001; aOR, 1.52; 95% CI, 1.16–2.00). Inter-hospital transfers to TCHs occurred in 17.4% of those initially routed to a PSH and was associated with the greater chance of EVT compared to remaining at PSHs (34.8% vs. 7.5%, P < 0.001), but not with better outcomes. @*Conclusion@#Two-thirds of EVT candidates were initially routed to PSHs despite greater chance of receiving EVT and having favorable outcomes if routed to a TCH in Korea. Process improvement is needed to direct appropriate patients to TCHs.

Acute Stroke Care in Korea in 2013–2014: National Averages and Disparities

Background@#This study aimed to describe the current status of acute stroke care in Korea and explore disparities among hospitals and regions. @*Methods@#The 2013 and 2014 national stroke audit data and the national health insurance claims data were linked and used for this study. Stroke patients hospitalized via emergency rooms within 7 days of stroke onset were selected. @*Results@#A total of 19,608 patients treated in 216 hospitals were analyzed. Among them 76% had ischemic stroke; 15%, intracerebral hemorrhage (ICH); and 9%, subarachnoid hemorrhage (SAH). Of the hospitals, 31% provided inpatient stroke unit care. Ambulances were used in 56% of cases, and the median interval from onset to arrival was 4.5 hours. One-quarter of patients were referred from other hospitals. Intravenous thrombolysis (IVT) and endovascular treatment (EVT) rates were 11% and 4%, respectively. Three-quarters of the analyzed hospitals provided IVT and/or EVT, whereas 47% of hospitals providing IVT and 67% of hospitals providing EVT had less than one case per month. Decompressive surgery was performed on 28% of ICH patients, and clipping and coiling were performed in 17.2% and 14.3% of SAH patients, respectively. There were noticeable regional disparities between the various interventions, ambulance use, arrival time, and stroke unit availability. @*Conclusion@#This study describes the current status of acute stroke care in Korea. Despite quite acceptable quality of stroke care, it suggests regional and hospital disparities. Expansion of stroke units, stroke center certification or accreditation, and connections between stroke centers and emergency medical services are highly recommended.

Effect of carvedilol on premature ventricular complexes originating from the ventricular outflow tract

Background@#Carvedilol is one of the most effective beta-blockers in reducing ventricular tachyarrhythmias and mortality in patients with heart failure. One of the possible antiarrhythmic mechanisms of carvedilol is the suppression of store overload-induced Ca2+ release, especially for the triggered activity. @*Objectives@#Premature ventricular complex (PVC) originating from the ventricular outflow tract (OT) is the most common form of idiopathic PVC, and its main mechanism is related to triggered activity. We evaluate the efficacy of carvedilol to suppress the OT PVC. @*Methods@#The electronic medical records at our hospital were screened to identify OT PVC patients treated with carvedilol. Clinical, electrocardiographic, and Holter monitoring studies were reviewed. @*Results@#A total of 25 patients who underwent Holter monitoring before and after carvedilol administration were found and enrolled. The mean age of the patients was 54.9 ± 13.9 years, and the mean dose of carvedilol was 18.2 ± 10.2 mg (sustained release formulation, 8/16/32 mg). The 24-h burden of PVC in 18 (72%) of 25 patients was significantly reduced from 12.2 ± 9.7% to 4.4 ± 6.7% (P = 0.006). In seven patients, the burden of PVC was changed from 7.1 ± 6.1% to 9.8 ± 8.4% (P = 0.061). There was no difference in age, carvedilol dose, duration of treatment, ventricular function, and left atrial size between responding and non-responding groups. @*Conclusion@#In this retrospective pilot study, treatment with carvedilol showed PVC suppression in 72% of patients. Now, we are conducting a prospective, randomized, multicenter study to evaluate the effect of carvedilol on OT PVC (Clinical trial registration: FOREVER trial, Clinical-Trials.gov: NCT03587558).