Body surface potential map, an electric potential distribution on the body torso surface, enables us to infer the electrical activities of the heart. Therefore, observing electric potential projected to the torso surface can be highly useful for diagnosing heart diseases such as coronary occlusion. The BSPM for the heart of a patient show a higher level of sensitivity than 12-lead ECG. Relevant research has been mostly based on clinical statistics obtained from patients, and, therefore, a simulation for a variety of pathological phenomena of the heart is required. In this study, by using computer simulation, a body surface potential map was implemented according to various occlusion locations (distal, mid, proximal occlusion) in the left anterior descending coronary artery. Electrophysiological characteristics of the body surface during the ST segment period were observed and analyzed based on an ST isointegral map. We developed an integrated system that takes into account the cellular to organ levels, and performed simulation regarding the electrophysiological phenomena of the heart that occur during the first 5 minutes (stage 1) and 10 minutes (stage 2) after commencement of coronary occlusion. Subsequently, we calculated the bipolar angle and amplitude of the ST isointegral map, and observed the correlation between the relevant characteristics and the location of coronary occlusion. In the result, in the ventricle model during the stage 1, a wider area of ischemia led to counterclockwise rotation of the bipolar angle; and, during the stage 2, the amplitude increased when the ischemia area exceeded a certain size.
Cardiac Electrophysiology* ; Computer Simulation* ; Coronary Occlusion ; Coronary Vessels* ; Electrocardiography ; Electrophysiological Phenomena ; Electrophysiology ; Heart ; Heart Diseases ; Humans ; Ischemia ; Torso

PURPOSE: To evaluate the utility of ultrasonograpy(US) as a guide in deciding drainage methods and as a prognostic factor in the prediction of pleural fibrosis, and to compare the effects of drainage methods in patients with tuberculous pleural effusions. MATERIALS AND METHODS: In 51 patients with tuberculous pleural effusion, US patterns of pleural effusion were classified according to degree of septa into three groups, into three groups, as follows: anechoic (n=5), linear septa (n=15), and honeycombing septa (n=31). US-guided drainage methods, including thoracentesis (n=17), percutaneous catheter insertion (n=12), catheter insertion with urokinase instillation (n=22) were employed. Therapeutic effects were evaluated with follow-up chest radiographs after 3 and 6 months. RESULTS: Three months after the procedure, 43 of 51 effusions had drained effectively. US guided drainage failed in eight patients including two of six with linear septated effusion treated with thoracentesis, four of seven with honeycomb septated effusion treated with thoracentesis, and two of six with honeycombing septated effusion treated with catheter drainage. There was no drainage failure in patients with anechoic effusions and in patients with urokinase instillation. Late effects were assessed in 39 patients after 6 months. Follow-up radiographs available in 39 patients demonstrated pleural fibrosis with intercostal space narrowing in 7 patients with honeycomb septated effusion, 3 patients with linear septated effusion, and none of the patients with anechoic effusions. CONCLUSION: The pattern of septa seen on US could be a useful factor for determining drainage methods and predicting late results in tuberculous pleural effusion. Percutaneous catheter drainage with urokinase instillation was a good drainage modality for patients with septated pleural effusions. Pleural fibrosis is more frequently induced by septated pleural effusion than by anechoic pleural effusion.
Catheters ; Drainage* ; Fibrosis ; Follow-Up Studies ; Humans ; Pleural Effusion* ; Radiography, Thoracic ; Ultrasonography* ; Urokinase-Type Plasminogen Activator

The physiomic approach is now widely used in the diagnosis of cardiovascular diseases. There are two possible methods for cardiovascular physiome: the traditional mathematical model and the machine learning (ML) algorithm. ML is used in almost every area of society for various tasks formerly performed by humans. Specifically, various ML techniques in cardiovascular medicine are being developed and improved at unprecedented speed. The benefits of using ML for various tasks is that the inner working mechanism of the system does not need to be known, which can prove convenient in situations where determining the inner workings of the system can be difficult. The computation speed is also often higher than that of the traditional mathematical models. The limitations with ML are that it inherently leads to an approximation, and special care must be taken in cases where a high accuracy is required. Traditional mathematical models are, however, constructed based on underlying laws either proven or assumed. The results from the mathematical models are accurate as long as the model is. Combining the advantages of both the mathematical models and ML would increase both the accuracy and efficiency of the simulation for many problems. In this review, examples of cardiovascular physiome where approaches of mathematical modeling and ML can be combined are introduced.
Cardiovascular Diseases ; Diagnosis ; Humans ; Jurisprudence ; Machine Learning ; Models, Theoretical ; Patient-Specific Modeling

Acute peripheral vestibulopathy, of which the chief complaint is positional vertigo, comprises benign paroxysmal positional vertigo (BPPV), labyrinthitis, labyrinthine fistula, and cerebellopontine angle tumors. Since the typical presentation of labyrinthine fistulas may be sensorineural hearing loss, positional vertigo, or disequilibrium, it is often difficult to distinguish from BPPV or Meniere's disease. Herein we report a 61-year-old female patient with typical symptoms and signs attributable to geotropic type variant of the lateral semicircular canal BPPV on the left side, who eventually was confirmed as having a labyrinthine fistula from chronic otitis media with cholesteatoma on the left side. This is another case where, even in the presence of isolated vertigo showing typical findings of acute peripheral vestibulopathy, other otologic symptoms and signs must not be overlooked.
Cholesteatoma* ; Ear, Inner ; Female ; Fistula* ; Hearing Loss, Sensorineural ; Humans ; Labyrinthitis ; Meniere Disease ; Middle Aged ; Neuroma, Acoustic ; Otitis Media ; Semicircular Canals ; Vertigo* ; Vestibular Neuronitis

Pseudo-vestibular neuritis is a central pathology of acute vestibular syndrome, characterized by unidirectional nystagmus mimicking acute peripheral vestibulophaty. We report a 39-year-old female patient who developed cerebellar infarction with isolated vertigo, spontaneous nystagmus, a positive head thrust test, and unilateral canal paresis in the contralesional side. The patient had no vascular risk factors. A diffusion-weighted image of the brain showed infarction of medial branch of posterior inferior and superior cerebellar artery on the left side. A magnetic resonance angiography of neck disclosed a wide range of diffused severe stenosis and narrowing of right and left vertebral arteries, respectively. This case suggests the possibility of vestibular ischemia masking the central pathology in isolated vertigo.
Adult ; Arteries ; Brain ; Constriction, Pathologic ; Embolism ; Female ; Head Impulse Test ; Humans ; Infarction ; Ischemia ; Magnetic Resonance Angiography ; Masks ; Neck ; Neuritis* ; Nystagmus, Pathologic ; Paresis* ; Pathology ; Risk Factors ; Vertebral Artery ; Vertebral Artery Dissection* ; Vertigo ; Vestibular Neuronitis

PURPOSE: A nationwide outbreak of Mycoplasma pneumoniae pneumonia (MP) refractory to macrolide antibiotics occurred in Korea during 2011. Steroid therapy has been reported to be both efficacious and well tolerated in pediatric patients with refractory MP. We compared clinical features and laboratory characteristics between children with refractory MP requiring steroid treatment and those with macrolide-responsive MP and evaluated the risk factors associated with refractory MP. METHODS: We investigated 203 children who were admitted to our institution with MP from June to November 2011. Refractory MP was defined by persistent fever over 38.3degrees C with progressive pulmonary consolidation or pleural effusion despite administration of appropriate macrolide antibiotics for 5 days or longer after admission. Steroid therapy was initiated on the fifth day after admission for refractory cases. RESULTS: There were 26 patients with refractory MP requiring steroid therapy. The mean duration of steroid therapy was 5.4 days and most of the patients were afebrile within 24 hours after initiation of steroid therapy. The prevalence of refractory MP was higher in patients with pleural effusion, lobar pneumonia affecting more than 2 lobes, higher levels of serum lactate dehydrogenase, increased oxygen requirements, and longer duration of hospitalization. Atopic sensitization and history of asthma were also associated with refractory MP after adjusting for age and gender. CONCLUSION: Children with refractory MP had more severe pneumonia. Atopic sensitization and history of asthma may be risk factors for refractory MP requiring steroid therapy in Korean children.
Anti-Bacterial Agents ; Asthma* ; Child* ; Fever ; Hospitalization ; Humans ; Korea ; L-Lactate Dehydrogenase ; Mycoplasma ; Mycoplasma pneumoniae* ; Oxygen ; Pleural Effusion ; Pneumonia* ; Pneumonia, Mycoplasma* ; Prevalence ; Risk Factors

PURPOSE: Atopic dermatitis (AD) is a chronic inflammatory relapsing skin disorder. Vitamin D plays a pivotal role in the development of AD, and interleukin (IL) 31 is known to be related to pruritus in AD. The aim of our study was to determine whether 25-hydroxyvitamin D (25(OH)D) levels are related to IL-31 levels or to the severity of AD. METHODS: We enrolled 91 children with AD and 32 control subjects without history or symptoms of allergic diseases. Blood was drawn to evaluate complete blood cell count, total eosinophil count (TEC), and total IgE, specific IgE to common allergens, 25(OH)D, and IL-31 levels. Serum 25(OH)D and IL-31 levels were measured using high-performance liquid chromatography and enzyme-linked immunosorbent assay, respectively. The scoring atopic dermatitis (SCORAD) index was used to evaluate the severity of AD. RESULTS: The mean 25(OH)D level was significantly lower in the AD group than in the control group; 25(OH)D decreased greatly in the moderate and severe AD groups compared with the mild AD group. Children with atopic sensitization showed significantly lower 25(OH)D levels than nonatopic children. However, serum IL-31 levels were not related to AD group, SCORAD index, or 25(OH)D levels. The SCORAD index was inversely correlated with serum 25(OH)D level and positively correlated with TECs and total IgE levels. Children with moderate and severe AD had significantly higher TECs than children with mild AD. CONCLUSION: Vitamin D is related to the severity of AD independently of IL-31.
Allergens ; Blood Cell Count ; Child* ; Chromatography, Liquid ; Dermatitis, Atopic* ; Enzyme-Linked Immunosorbent Assay ; Eosinophils ; Humans ; Immunoglobulin E ; Interleukins ; Pruritus ; Skin ; Vitamin D

BACKGROUND AND OBJECTIVES: Benign paroxysmal positional vertigo (BPPV) generally involves a single semicircular canal (single canal BPPV) but it has been reported that more than one semicircular canal on either the same or the opposite side can be involved in 6.8-20% of the cases (multiple canal BPPV). In this study, the clinical characteristics of multiple canal BPPV were analyzed and compared to those of single canal BPPV. MATERIALS AND METHODS: Retrospective analysis was performed on 1054 consecutive patients diagnosed with BPPV. Multiple canal BPPV was diagnosed when the combination of typical nystagmus was provoked by the Dix-Hallpike and supine head roll tests. Canalith repositioning maneuver was performed sequentially starting with the semicircular canal causing more severe nystagmus or symptoms. Clinical characteristics and the treatment course were statistically compared between single canal BPPV and multiple canal BPPV. RESULTS: Among the 1054 patients, single canal BPPV was diagnosed in 1005 patients (95.4%) while multiple canal BPPV was diagnosed in 49 patients (4.6%). BPPV involving semicircular canals on the same side was more common (79.6%) than BPPV with bilateral involvement. The most common combination of the involved canals was ipsilateral posterior and horizontal semicircular canals (63.3%). Multiple canal BPPV was significantly more associated with underlying otologic diseases, especially labyrinthitis. Multiple canal BPPV required more treatment sessions and longer duration of treatment to achieve resolution of nystagmus and symptoms. CONCLUSIONS: As all cases of multiple canal BPPV were treated successfully although a longer duration of treatment and more treatment sessions were required compared to single canal BPPV, the results of our study could aid in making an accurate diagnosis and providing appropriate treatment of multiple canal BPPV.
Diagnosis ; Ear Diseases ; Ear, Inner ; Head ; Humans ; Labyrinthitis ; Retrospective Studies ; Semicircular Canals* ; Vertigo*

Although complex fractionated electrogram (CFE) is known to be a target for catheter ablation of fibrillation, its physiological meaning in fibrillation wave-dynamics remains to be clarified. We evaluated the spatiotemporal relationships among the parameters of fibrillation wave-dynamics by simulation modeling. We generated maps of CFE-cycle length (CFE-CL), local dominant frequency (LDF), wave break (WB), and phase singularity (PS) of fibrillation in 2-dimensional homogeneous bidomain cardiac modeling (1,000 x 1,000 cells ten Tusscher model). We compared spatiotemporal correlations by dichotomizing each maps into 10 x 10 lattice zones. In spatial distribution, WB and PS showed excellent correlation (R = 0.963, P < 0.001). CFE-CL had weak correlations with WB (R = 0.288, P < 0.001), PS (R = 0.313, P < 0.001), and LDF (R = -0.411, P < 0.001). However, LDF did not show correlation with PS or WB. PSs were mostly distributed at the periphery of low CFE-CL area. Virtual ablation (5% of critical mass) of CFE-CL < 100 ms terminated fibrillation at 14.3 sec, and high LDF ablation (5% of critical mass) changed fibrillation to organized tachycardia, respectively. In homogeneous 2D fibrillation modeling, CFE-CL was weakly correlated with WB, PS, and LDF, spatiotemporally. PSs are mostly positioned at the periphery of low CFE-CL areas, and virtual ablation targeting low CFE-CL regions terminated fibrillation successfully.
Algorithms ; Atrial Fibrillation/*physiopathology ; Body Surface Potential Mapping ; Catheter Ablation ; *Electrocardiography ; Electrodes ; Heart Atria/physiopathology ; Humans ; *Models, Biological

PURPOSE: Premature and low birth weighted (LBW) infants as well as small for gestational age (SGA) infants have a high death rate and increasing the prevalence rate. We compared the proportion of these high-risk neonates and the relevant factor between the four regional settings. METHODS: We reviewed the data from 2005 to 2010, from the Korea National Statistics Office and compared the proportions of premature infants, LBW infants and SGA babies and the relevant factors between Seoul, metropolitan cities and small-to-medium-sized ones. RESULTS: Premature birth rate is as follows in each area: 4.00% in Seoul, 4.21% in metropolitan areas, 4.11% in small and medium size cities, and 4.27% in small towns. SGA birth rate is slightly lower in the medium-sized cities and higher in small towns. The birth rate of low birth weight infants is higher only in small towns (3.58%). It appears that low maternal age and low maternal education levels increase these high-risk newborns. Once calibrated variables, the result showed that the risk of premature infants is higher in the metropolitan areas (OR, 1.05), and the risk of SGA (OR, 1.06) and low birth weight (1.03) is higher in a small town. CONCLUSIONS: There were significant differences in the premature infants, low birth weight infants and SGA babies between the four different regional settings. Following the adjustment of the relevant variables, the proportion premature infant was higher in metropolitan cities and SGA babies and LBW infants were higher in small ones.
Birth Rate ; Gestational Age ; Humans ; Incidence ; Infant ; Infant, Low Birth Weight ; Infant, Newborn ; Infant, Premature ; Korea ; Maternal Age ; Mothers ; Premature Birth ; Prevalence