• Clinical and Experimental Pediatrics
• /
• v.50 no.11
• /
• pp.1085-1090
• /
• 2007

Purpose : Radiofrequency catheter ablation (RFCA) has become an effective therapeutic modality for treating pediatric tachyarrhythmias. Using conventional RFCA catheters, ablation of parahisian accessory pathways may be difficult and have high risk for heart block. We reviewed the efficacy and complications of the RFCA in children and adolescent with arrhythmias including parahisian accessory pathways. Methods : We studied 48 patients (aged 2 years to 20 years) who had undergone RFCA from August 2003 to March 2007. We reviewed clinical findings, electrophysiologic studies, RFCA data, complications, and follow-up results of the patients. Results : Mean age of the patients was 13.1 years. Numbers and types of arrhythmias (age, acute success rate) were as follows: 19 WPW syndrome including 5 parahisian accessory pathways ($13.7{\pm}4.6yr$, 18/19), 11 atrioventricular reentrant tachycardia with concealed bypass tract ($12.3{\pm}5.0yr$, 10/11), 13 atrioventricular nodal reentrant tachycardia ($12.6{\pm}4.4yr$, 13/13), 4 atrial flutter ($13.0{\pm}7.4yr$, 3/4), and 1 ventricular tachycardia (20 yr, 1/1). Associated cardiac structural lesion was not detected in 48 patients. The recurrence rate was 6.5%, and the final success rate was 93.8%. Conclusion : These results suggest that RFCA is a highly effective treatment method in children and adolescent with tachyarrhythmia.

• Journal of Chest Surgery
• /
• v.32 no.8
• /
• pp.749-752
• /
• 1999

Over the past several years, a number of centers have reported favorable results of anatomical repair for the congenitally corrected transpositions. However, there have been subsequent problems related mainly to the results of atrial switch procedures in patients who had small atriums because of venoatrial obstructions or supraventricular arrhythmias, especially in patients with apicocaval juxtaposition. Cavopulmonary shunt may be a useful addition to the double switch operation in certain circumstances as a means of avoiding potential atrial complications. Herein, we describe the successful anatomical repair of congenitally corrected transposition of the great artery with pulmonary atresia, ventricular septal defect, and cavo apical juxtaposition with this modification.

• Journal of Internet Computing and Services
• /
• v.8 no.1
• /
• pp.125-132
• /
• 2007

This paper presents an approach to detect premature ventricular contractions(PVC) using the neural network with weighted fuzzy membership functions(NEWFM), NEWFM classifies normal and PVC beats by the trained weighted fuzzy membership functions using wavelet transformed coefficients extracted from the MIT-BIH PVC database. The eight most important coefficients of d3 and d4 are selected by the non-overlap area distribution measurement method. The selected 8 coefficients are used for 3 data sets showing reliable accuracy rates 99,80%, 99,21%, and 98.78%, respectively, which means the selected input features are less dependent to the data sets. The ECG signal segments and fuzzy membership functions of the 8 coefficients enable input features to interpret explicitly.

• Proceedings of the KOSOMBE Conference
• /
• v.1997 no.11
• /
• pp.222-227
• /
• 1997

To diagnose cardiac arrhythmia owing to reentry mechanism, cardiac conduction system was modeled by modified Hidden Markov modeled by evaluated. First, simulation of transient conduction states and output waves were made with initially assumed parametric values of cardiac muscle repolariztion time, conduction velocity and its automaticity. The output was a series of onset time and the name of the wave. Parameters determined the rate of beating, lengths of wave intervals, rate of abnormal beats, and the like. Several parameter sets were found to simulate normal sinus rhythm, supraventricular /ventricular tachycardia, atrial /vetricular extrasystole, etc. Then, utilizing the estimation theorems of Hidden Markov Model, the best conduction path was estimated given the previous output. With this modified estimation method, close matching between the simulated conduction path and the estimated one was confirmed.

• Journal of Chest Surgery
• /
• v.39 no.6 s.263
• /
• pp.486-489
• /
• 2006

A 16 year-old boy was admitted to our department because of mild chest discomfort and mild dyspnea. A mass involving posterior wall of the left ventricle near posterior mitral annulus was found on echocardiography and cardiac MRI. Total excision of the mass was performed via posterior ventriculotomy under the cardiopulmonary bypass. The pathologic diagnosis revealed mature cardiac myocyte hamartoma. There was no evidence of arrhythmia and tumor recurrence during the 1 year of follow up after the surgery.

• Journal of Chest Surgery
• /
• v.40 no.9
• /
• pp.633-636
• /
• 2007

Coronary artery spasm immediately after the coronary artery bypass graft (CABG) surgery is rare but it can cause sudden and severe hypotension or a ventricular arrhythmia. We report a case of low cardiac output syndrome caused by a right coronary artery spasm following CABG that did not show any significant stenotic lesions on preoperative coronary angiography.

• Journal of Chest Surgery
• /
• v.29 no.11
• /
• pp.1202-1206
• /
• 1996

Ebstein's anomaly is an unusual and a rare congenital cardiac malformation but characteristic abnormality of the development of the tricuspid valve, right atrium and ventricle. The characteristic findings are a displaced tricuspid valve with a septal leaflet spiralling into the right ventricle. The surgical correction is variable and are left unsolved problem in surgical treatment of anomaly. Between January 1988 ＆ December 1995, we experienced 11 cases of Ebstein's anomaly and associated cardiac anomalies are ASD, PFO, ASD with VSD. The typically displaced tricuspid valve leaflet was found in all cases. In the NYHA functional classification, three were in class II, seven were in class III, and one was in class IV. Nine patients were operated by tricuspid annuloplasty ＆ plication with Danielson's method and two patients were done by tricuspid valve replacement with plication, and in all cases associated anomaly was corrected. Postoperatively, five patients suffered from complication - low cardiac output syndrome, arrhythmia and wound infection. There was no operative mortality and the postoperative courses were relatively good conditions with more improvement of symptoms.

• Clinical and Experimental Pediatrics
• /
• v.46 no.5
• /
• pp.490-494
• /
• 2003

Purpose : We'd like to determine the incidence of congenital heart disease and arrhythmia in elementary school children in Busan, and to provide adequate prevention and treatment. Methods : A total of 23,802(male 12,909, female 10,893) 1st grade elementary school children living in Busan were studied. All children were 7-8 years old. We obtained their medical history by questionnaire and checked elecrocardiography(ECG). Subsequent screening tests including a 2nd ECG, chest X-ray, phonocardiogram and CBC for the students who had abnormal findings at the first screening test. The third screening test was done for students who had cardiac murmurs or abnormal ECG findings in the second screening test by echocardiogram, treadmill test and 24-hour Holter monitoring. Results : Among 23,802 children participants, 605(2.54%) had abnormal ECG findings at the first screening test. Q wave abnormality(0.58%) was observed most frequently, and complete right bundle branch block(RBBB)(0.26%), sinus tachycardia(0.24%), right axis deviation(0.22%) and ventricular premature contraction(VPC)(0.21%) followed in order. Four hundred and twenty four children participated in the second ECG screening test. Two hundred and two children(47.6%) had an abnormality such as sinus tachycardia(18.8%), VPC(17.8%), or complete RBBB(17.3%). After completing the third examination including echocardiogram, we couldn't find the students with ventricular tachycardia (VT) or SVT at the third arrhythmia screening test. Conclusion : A high incidence of arrhythmia was found in the 1st grade elementary school children in Busan despite their healthy appearances, although fatal heart diseases were not noted. Early diagnosis, adequate preventative measures and treatment will prevent and decrease the frequency of emergent situations like syncope and sudden death.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.2
• /
• pp.450-460
• /
• 2017

T wave is cardiac parameters that represent ventricular repolarization, it is very important to diagnose arrhythmia. Several methods for detecting T wave have been proposed, such as frequency analysis and non-linear approach. However, detection accuracy is at the lower level. This is because of the overlap of the P wave and T wave depending on the heart condition. We propose T wave detection algorithm based on target area extraction through QRS cancellation and moving average. For this purpose, we detected Q, R, S wave from noise-free ECG(electrocardiogram) signal through the preprocessing method. And then we extracted P, T target area by applying decision rule for four PAC(premature atrial contraction) pattern another arrhythmia through moving average and detected T wave using RT interval and threshold of RR interval. The performance of T wave detection is evaluated by using 48 record of MIT-BIH arrhythmia database. The achieved scores indicate the average detection rate of 95.32%.

• Journal of Chest Surgery
• /
• v.43 no.1
• /
• pp.58-62
• /
• 2010

Rastelli repair has been considered the procedure of choice for surgically repairing transposition of the great arteries combined with ventricular septal defect and pulmonary stenosis. However, the long term results have been less than optimal and these patients who ungo this procedure can eventually display conduit obstruction, left ventricular outflow tract obstruction and arrhythmias. Many new procedures are now available and they are technically challenging for making a more normal anatomic repair. In our hospital, two patients who had a TGA with VSD and PS have been repaired with a Half Turned Truncal Switch Operation and a Lecompte maneuver in 2003 and 2006, respectively. We report on our two experiences with performing a Half Turned Truncal Switch Operation, and we discuss the changes of the biventricular outflow tract.