• The Korean Journal of Pharmacology
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• v.14 no.1_2
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• pp.41-46
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• 1978

The effects of sodium taurocholate(STC) and sodium deoxycholate(SDC) on cardiac function were examined by using isolated atria of rabbit and guinea pig and heart of anesthetized frog. Also the antiarrythmic action of STC and SDC on atrial arrhythmias induced by epinephrine or ouabain was studied. The results were following. The cholates exhibited a slight decrease in rate and contractile amplitude of the isolated rabbit atria. The cholates abolished partially the spontaneous arrhythmic occurring in isolated rabbit and guinea pig atria but no effect on the atrial arrhythmia induced by ouabain and epinephrine was observed. Concomitant administration of cholates with ouabain produced a marked prolongation of atrial arrhythmia in comparison to that of ouabain alone in both isolated rabbit and guinea pig atria. The cholates exhibited a marked prolongation in ventricular arrhythmia and cardiac arrest time in comparison to that of ouabain treatment. However, the combined treatment with cholates and ouabain produced a slight prolongation in comparison to that of ouabain alone in the heart of anesthetized frog. The above results suggest that cholates have a slight antiarrythmic effect on the heart but this effectiveness is different from those of propranolol that is non-selective antiarrhythmic drug.

• Journal of Korean Critical Care Nursing
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• v.7 no.2
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• pp.14-23
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• 2014

Purpose: The purpose of this study was to provide basic information to develop appropriate nursing guidelines for cardiac telemetry. Methods: This retrospective research was conducted to identify the current usage of cardiac telemetry and considered 1,000 patients hospitalized for telemetry. The collected data were analyzed using IBM (SPSS Statistics for Windows 21.0). Results: Four-hundred and ninety-two patients (49.2%) were diagnosed with arrhythmia and 209 (20.9%) with heart failure. Electrocardiogram (ECG) rhythm changes were detected via telemetry in 464 cases. Major arrhythmias were ventricular tachycardia (183, 39.4%) and bradycardia (99, 21.3%). Interventions after detecting arrhythmia were cardioversion (16, 3.4%), defibrillation (1, 0.2%), and cardiopulmonary cerebral resuscitation (5, 1.1%); other patients were treated conservatively with close observation (381, 82.1%). Conclusion: There was appropriate intervention in 46.4% of the considered cases with the detection of ECG changes before patient notification, which implied that cardiac telemetry could be considered for application to patients with hemodynamic instability. Clear standards and guidelines are required to determine who requires telemetry and when to end the telemetry monitoring.

• Clinical and Experimental Pediatrics
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• v.49 no.9
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• pp.930-936
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• 2006

Although antiarrhythmic medication has been the main treatment modality for arrhythmia in children, in recent decades technological development and computerization have made great advances in nonpharmacological therapy. This article reviews the transcatheter radiofrequency ablation for tachycardia in children, recent advances of device therapy for bradycardia, antitachycardia pacing, implantable cardioverter defibrillator. As a new field of device therapy, cardiac resynchronization therapy for congestive heart failure is also mentioned.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.221-223
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• 2010

Considering the similarity between fluid vortex and arrhythmogenic reentrant waves in heart, we applied the non-dimensionalization method in fluid dynamics to arrhythmia analysis and discovered a new non-dimensional simulation results, there was a threshold value of the number that resulted in the induction of a reentrant wave.

• Proceedings of the KOSOMBE Conference
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• v.1991 no.05
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• pp.94-97
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• 1991

It is well known that multipoint and computerized intraoperative mapping systems improve the results of surgery for Wolff-Parkinson-White syndrome and show tremendous potential for opening an entirely new era of surgical intervention for the more common and lethal types of supraventricular tachyarrhythmias such as atrial flutter and atrial fibrillation. In addition, the ability to map and ablate the sometimes fleeting automatic atrial tachycardia is greatly enhanced by computerized mapping systems. In this study, we have developed 16 channel computerized data analysis system using microcomputer for basic research of electrophysiology and electrical propagation. This system is expected to enable us to study pathophysiology of cardiac arrhythmia and to improve the results of diagnosis and surgical treatment for cardiac arrhythmia.

• Investigative Magnetic Resonance Imaging
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• v.18 no.3
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• pp.244-252
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• 2014

Purpose : We proposed a multi-physiological signals based real-time intelligent triggering system(MITS) for Cardiac MRI. Induced noise of the system was analyzed. Materials and Methods: MITS makes cardiac MR imaging sequence synchronize to the cardiac motion using ECG, respiratory signal and second order derivative of $SPO_2$signal. Abnormal peaks due to arrhythmia or subject's motion are rejected using the average R-R intervals and R-peak values. Induced eddy currents by gradients switching in cardiac MR imaging are analyzed. The induced eddy currents were removed by hardware and software filters. Results: Cardiac MR images that synchronized to the cardiac and respiratory motion are acquired using MITS successfully without artifacts caused by induced eddy currents of gradient switching or subject's motion or arrhythmia. We showed that the second order derivative of the $SPO_2$ signal can be used as a complement to the ECG signals. Conclusion: The proposed system performs cardiac and respiratory gating with multi-physiological signals in real time. During the cardiac gating, induced noise caused by eddy currents is removed. False triggers due to subject's motion or arrhythmia are rejected. The cardiac MR imaging with free breathing is obtained using MITS.

• Korean Journal of Radiology
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• v.20 no.1
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• pp.114-125
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• 2019

Objective: Segmented cardiac cine magnetic resonance imaging (MRI) is the gold standard for cardiac ventricular volumetric assessment. In patients with difficulty in breath-holding or arrhythmia, this technique may generate images with inadequate quality for diagnosis. Real-time cardiac cine MRI has been developed to address this limitation. We aimed to assess the performance of retrospective electrocardiography-gated real-time cine MRI at 3T for left ventricular (LV) volume and mass measurement. Materials and Methods: Fifty-one patients were consecutively enrolled. A series of short-axis cine images covering the entire left ventricle using both segmented and real-time balanced steady-state free precession cardiac cine MRI were obtained. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), and LV mass were measured. The agreement and correlation of the parameters were assessed. Additionally, image quality was evaluated using European CMR Registry (Euro-CMR) score and structure visibility rating. Results: In patients without difficulty in breath-holding or arrhythmia, no significant difference was found in Euro-CMR score between the two techniques (0.3 ± 0.7 vs. 0.3 ± 0.5, p > 0.05). Good agreements and correlations were found between the techniques for measuring EDV, ESV, EF, SV, and LV mass. In patients with difficulty in breath-holding or arrhythmia, segmented cine MRI had a significant higher Euro-CMR score (2.3 ± 1.2 vs. 0.4 ± 0.5, p < 0.001). Conclusion: Real-time cine MRI at 3T allowed the assessment of LV volume with high accuracy and showed a significantly better image quality compared to that of segmented cine MRI in patients with difficulty in breath-holding and arrhythmia.

• The Journal of the Korean life insurance medical association
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• v.18
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• pp.103-106
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• 1999

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.1
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• pp.16-22
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• 2010

Electrocardiogram(ECG) analysis and arrhythmia recognition are critical for diagnosis and treatment of ill patients. Cardiac arrhythmia is a condition in which heart beat may be irregular and presents a serious threat to the patient recovering from ventricular tachycardia (VT) and ventricular fibrillation (VF). Other arrhythmias like atrial premature contraction (APC), Premature ventricular contraction (PVC) and superventricular tachycardia (SVT) are important in diagnosing the heart diseases. This paper presented new method to classify various arrhythmias contrary to other techniques which are limited to only two or three arrhythmias. ECG is decomposed into Intrinsic Mode Functions (IMFs) by Empirical Mode Decomposition (EMD). Burg algorithm was performed on IMFs to obtain AR coefficients which can reduce the dimension of feature vector and utilized as Multi-class SVM inputs which is basically extended from binary SVM. We chose optimal parameters for SVM classifier, applied to arrhythmias classification and achieved the accuracies of detecting NSR, APC, PVC, SVT, VT and VP were 96.8% to 99.5%. The results showed that EMD was useful for the preprocessing and feature extraction and multi-class SVM for classification of cardiac arrhythmias, with high usefulness.

• The Journal of Korean Medicine
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• v.42 no.3
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• pp.44-55
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• 2021

Objectives: As the use of herbal medicinal products (HMPs) increases worldwide, systematic verification of the safety of HMPs is required. The induction of cardiotoxicity is one of the major factors in post-approval withdrawal of medicinal products, and drug-induced cardiotoxicity assessment is emerging as an important step in drug development. In the present study, we evaluated human ether-à-go-go-related gene (hERG) potassium channel-related cardiotoxicity to predict the risk of cardiac arrhythmia in thirteen herbal medicines known to have cardiac toxicity. Methods: We measured the inhibition rate of hERG potassium channel activity of 13 medicinal herbal extracts in hERG-expressing HEK 293 cells using an automated patch-clamping system. Quinidine was used as a positive control for inhibition of hERG activity. Results: Extracts of Evodiae Fructus, Strychni Semen, and Corydalis Tuber potently inhibited the activity of hERG, and IC₅₀ values were 3.158, 19.87, and 41.26 ㎍/mL, respectively. Cnidi Fructus, Ephedra Herba, Lithospermi Radix, Polygoni Multiflori Radix, Visci Ramulus et Folium, Asiasari Radix et Rhizoma, and Scolopendra weakly inhibited hERG activity, and the IC₅₀ value for each herbal medicine was more than 400 ㎍/mL. Aconiti Kusnezoffii Tuber and two types of Aconiti Lateralis Radix Preparata (Po and Yeom) had weak inhibitory activity against hERG, and the IC₅₀ values were more than 700 ㎍/mL. The IC₅₀ value of quinidine against hERG was 1.021 𝜇M. Conclusion: Evodiae Fructus, Strychni Semen, and Corydalis Tuber acted as potent inhibitors against hERG. These herbal medicines may cause cardiac arrhythmia through QT prolongation, so care should be taken when taking them.