2.A Case of Idiopathic Long QT Syndrome with 2:1 Atrioventricular Block.
Kwang In LEE ; Chul Ha KIM ; In Seok LIM ; Dong Keun LEE ; Byoung Hoon YOO
Journal of the Korean Pediatric Society 1995;38(12):1701-1705
No abstract available.
Atrioventricular Block*
;
Long QT Syndrome*
3.Marked QT prolongation and T inversion in a patient with acute pulmonary thromboembolism.
Tae Ik PARK ; Jun KIM ; Taek Jong HONG ; Yung Woo SHIN
Korean Journal of Medicine 2008;75(1):37-38
No abstract available.
Electrocardiography
;
Humans
;
Long QT Syndrome
;
Pulmonary Embolism
4.Taxifolin Glycoside Blocks Human ether-a-go-go Related Gene K+ Channels.
Jihyun YUN ; Hyemi BAE ; Sun Eun CHOI ; Jung Ha KIM ; Young Wook CHOI ; Inja LIM ; Chung Soo LEE ; Min Won LEE ; Jae Hong KO ; Seong Jun SEO ; Hyoweon BANG
The Korean Journal of Physiology and Pharmacology 2013;17(1):37-42
Taxifolin glycoside is a new drug candidate for the treatment of atopic dermatitis (AD). Many drugs cause side effects such as long QT syndrome by blocking the human ether-a-go-go related gene (hERG) K+ channels. To determine whether taxifolin glycoside would block hERG K+ channels, we recorded hERG K+ currents using a whole-cell patch clamp technique. We found that taxifolin glycoside directly blocked hERG K+ current in a concentration-dependent manner (EC50=9.6+/-0.7 microM). The activation curve of hERG K+ channels was negatively shifted by taxifolin glycoside. In addition, taxifolin glycoside accelerated the activation time constant and reduced the onset of the inactivation time constant. These results suggest that taxifolin glycoside blocks hERG K+ channels that function by facilitating activation and inactivation process.
Dermatitis, Atopic
;
Humans
;
Long QT Syndrome
;
Quercetin
5.Clinical characteristics of 5 Chinese LQTS families and phenotype-genotype correlation.
Jiangfang, LIAN ; Changcong, CUI ; Xiaolin, XUE ; Chen, HUANG ; Hanbin, CUI
Journal of Huazhong University of Science and Technology (Medical Sciences) 2004;24(3):208-11
In order to assess the clinical manifestations and electrocardiogram (ECG) characteristics of Chinese long QT syndrome (LQTS) patients and describe the phenotype-genotype correlation, the subjects from 5 congenital LQTS families underwent clinical detailed examination including resting body surface ECG. QT interval and transmural dispersion of repolarization (TDR) were manually measured. Five families were genotyped by linkage analysis (polymerase chain reacting-short tandem repeat, PCR-STR). The phenotype-genotype correlation was analyzed. Four families were LQT2, 1 family was LQT3. Twenty-eight gene carriers were (14 males and 14 females) identified from 5 families. The mean QTc and TDRc were 0.56 +/- 0.04 s (range 0.42 to 0.63) and 0.16 +/- 0.04 s (range 0.09 to 0.24) respectively. 35.7% (10/28) had normal to borderline QTc (< or = 0.460 s). There was significant difference in QTc and TDRc between the patients with symptomatic LQTS and those with asymptomatic LQTS, and there was significant difference in TDRc between the asymptomatic patients and normal people also. A history of cardiac events was present in 50% (14/28), including 9 with syncope, 2 with sudden death (SD) and occurred in the absence of beta-blocker. Three SDs occurred prior to the diagnosis of LQTS and had no ECG record. Two out of 5 SDs (40%) occurred as the first symptom. Typical LQT2 T wave pattern were found in 40% (6/15) of all affected members. The appearing-normal T wave was found in one LQT3 family. Low penetrance of QTc and symptoms resulted in diagnostic challenge. ECG patterns and repolarization parameters may be used to predict the genotype in most families. Genetic test is very important for identification of gene carriers.
Arrhythmia/etiology
;
Arrhythmia/genetics
;
Asian Continental Ancestry Group
;
Electrocardiography
;
Genotype
;
Long QT Syndrome/complications
;
Long QT Syndrome/congenital
;
Long QT Syndrome/*genetics
;
Pedigree
;
*Phenotype
6.Torsades de pointes observed in the early postoperative period in a patient with long QT syndrome.
Min Soo KIM ; Seung Gyun NAM ; Yong Seon CHOI
Korean Journal of Anesthesiology 2013;64(1):89-90
No abstract available.
Humans
;
Long QT Syndrome
;
Postoperative Period
;
Torsades de Pointes
9.Intrapericardial Implantation of an Implantable Cardioverter-Defibrillator in a Child.
Yong Won SEONG ; Woong Han KIM ; Jae Suk YOO ; Hye seon KIM ; Byoung Ju MIN ; Young Ok LEE
The Korean Journal of Thoracic and Cardiovascular Surgery 2011;44(1):61-63
Implantable cardioverter defibrillator (ICD) can be a crucial therapeutic modality for pediatric patients with congenital heart disease, Brugada syndrome, long QT syndrome and cardiomyopathy. Because transvenous implantation of ICD is mostly unfeasible for pediatric patients due to anatomical and technical limitations, epicardial patch type or subcutaneous type ICD have been used. Implantation of these alternative ICDs, however, was reported to be frequently associated with significant complications. We report a case of successful intrapericardial implantation of a single coil-type ICD through the transverse sinus in a 27 month-old child weighing lesser than 10 kg, and it was inferred from this experience that this alternative technique may decrease complications and morbidities after ICD implantation in children.
Arrhythmias, Cardiac
;
Brugada Syndrome
;
Cardiomyopathies
;
Child
;
Defibrillators
;
Defibrillators, Implantable
;
Heart Diseases
;
Humans
;
Long QT Syndrome
10.The corrected QT (QTc) prolongation in hyperthyroidism and the association of thyroid hormone with the QTc interval.
Ye Seung LEE ; Joong Wan CHOI ; Eun Ju BAE ; Won Il PARK ; Hong Jin LEE ; Phil Soo OH
Korean Journal of Pediatrics 2015;58(7):263-266
PURPOSE: Ventricular repolarization is assessed using the QT interval corrected by the heart rate (QTc) via an electrocardiogram (ECG). Prolonged QTc is associated with an increased risk of arrhythmias and cardiac mortality. As there have been few reports regarding the effects of hyperthyroidism on ventricular repolarization, we studied the association between serum free thyroxine (free T4 [fT4]) and thyroid stimulating hormone (TSH) levels and the QTc interval. METHODS: Thirty-eight patients with hyperthyroidism (<30 years old) were included, and we used their clinical records and available ECGs (between August 2003 and August 2011) to evaluate the association between their fT4 and TSH levels and their QTc interval. In addition, we studied the ECGs of 72 age-matched patients with no hyperthyroidism (control group) and compared their data with that from the patients group. RESULTS: The QTc duration in patients with hyperthyroidism was significantly prolonged compared to that in the control subjects (P<0.001). In addition, the number of hyperthyroid patients with abnormal prolonged QTc was significantly higher than that in the control group (P<0.001). Among the patients with hyperthyroidism, patients with prolonged QTc and borderline QTc had higher fT4 levels and there was positive correlation between their fT4 levels and their QTc interval (P<0.05). However, no correlation was observed between their TSH levels and their QTc interval. CONCLUSION: We report that hyperthyroidism is associated with QTc prolongation. The correlation between the fT4 levels and the QTc interval suggests that thyroid status is associated with QTc values and the risk of cardiac mortality.
Arrhythmias, Cardiac
;
Electrocardiography
;
Heart Rate
;
Humans
;
Hyperthyroidism*
;
Long QT Syndrome
;
Mortality
;
Thyroid Gland*
;
Thyrotropin
;
Thyroxine