Clinical and Genetic Features of Korean Inherited Arrhythmia Probands
CONCLUSIONS: There were significant differences in clinical characteristics and genetic yields among BrS, LQTS, and IVF. Genetic testing did not provide better yield for BrS and LQTS. On the other hand, in IVF, genetic testing using multiple gene panel might enable the molecular diagnosis of concealed genotype, which may alter future clinical diagnosis and management strategies.PMID:37653714 | DOI:10.4070/kcj.2023.0083 (Source: Korean Circulation Journal)
Source: Korean Circulation Journal - September 1, 2023 Category: Cardiology Authors: Joo Hee Jeong Suk-Kyu Oh Yun Gi Kim Yun Young Choi Hyoung Seok Lee Jaemin Shim Yae Min Park Jun-Hyung Kim Yong-Seog Oh Nam-Ho Kim Hui-Nam Pak Young Keun On Hyung Wook Park Gyo-Seung Hwang Dae-Kyeong Kim Young-Ah Park Hyoung-Seob Park Yongkeun Cho Seil Oh Source Type: research

Po-05-209 t-wave alternans measured by 24-hour ambulatory recording superior to exercise stress test as a risk stratification marker in lqts patients
T wave alternans (TWA) is a risk factor for life-threatening arrhythmic events (LAEs) in long QT syndrome(LQTS) patients. Few small-sample studies have quantified the TWA value by 24-hour ambulatory recording or exercise stress test, and the cut-off point of TWA ≥47 mV was based on myocardial infarction patients(ATRAMI study). In our study, we aimed (1) to compare the predictive model of LAE according to the TWA value measured by 24-hour ambulatory recording and exercise stress test; (2) to propose a new TWA cutpoint for abnormality in LQTS patients; (3) to analyse the association of TWA with LAE. (Source: Heart Rhythm)
Source: Heart Rhythm - August 28, 2023 Category: Cardiology Authors: Jing Yang, Ping Zhang Source Type: research

Po-03-212 mapping and ablation of the epicardial electroanatomic substrate in long-qt syndrome patients at risk of sudden death
Among inherited cardiogenetic diseases, electroanatomic mapping (EAM) revealed the existence of distinct epicardial substrates whose homogenization by radiofrequency ablation (RFA) was effective in preventing ventricular arrhythmias. The long QT syndrome (LQTS) is a leading cause of sudden cardiac death (SCD). Until now, we have had no means to establish the degree to which this inherited condition arises from an underlying electroanatomic arrhythmogenic substrate. (Source: Heart Rhythm)
Source: Heart Rhythm - August 28, 2023 Category: Cardiology Authors: Carlo Pappone, Giuseppe Ciconte, Luigi Anastasia, Antonio Boccellino, Gabriele Negro, Fiorenzo Gaita, Emanuele MIcaglio, Emanuela T. Locati, Gabriele Vicedomini, Vincenzo Santinelli Source Type: research

Long QT syndrome presenting as fetal bradycardia and 2:1 atrioventricular block in a preterm infant
We present a case of a male infant born by emergency caesarean section for fetal bradycardia detected in the context of a maternal intercurrent illness at 31+5 weeks’ gestation. He was born vigorous despite a heart rate of 65–80 beats/min. ECG at birth (figure 1) demonstrates a ‘pseudo-block’ phenomenon arising from a profoundly prolonged QT interval (633 ms). Non-conducted P waves occur before the T wave of the preceding QRS as the ventricles have not repolarised before the atria contract for the second time (figure 2). On diagnosis of long QT syndrome (LQTS), propranolol was started. No ventricula...
Source: Archives of Disease in Childhood - Fetal and Neonatal Edition - August 17, 2023 Category: Perinatology & Neonatology Authors: Kelleher, S. T., Prendiville, T., Carroll, A. Tags: Images in neonatal medicine Source Type: research

Calmodulin mutations affecting Gly114 impair binding to the NaV1.5 IQ-domain
Missense variants in CALM genes encoding the Ca2+-binding protein calmodulin (CaM) cause severe cardiac arrhythmias. The disease mechanisms have been attributed to dysregulation of RyR2, for Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) and/or CaV1.2, for Long-QT Syndrome (LQTS). Recently, a novel CALM2 variant, G114R, was identified in a mother and two of her four children, all of whom died suddenly while asleep at a young age. The G114R variant impairs closure of CaV1.2 and RyR2, consistent with a CPVT and/or mild LQTS phenotype. However, the children carrying the CALM2 G114R variant displayed a phenotype ...
Source: Frontiers in Pharmacology - August 16, 2023 Category: Drugs & Pharmacology Source Type: research

Novel combinations of variations in KCNQ1 were associated with patients with long QT syndrome or Jervell and Lange-Nielsen syndrome
Long QT syndrome (LQTS) is one of the primary causes of sudden cardiac death (SCD) in youth. Studies have identified mutations in ion channel genes as key players in the pathogenesis of LQTS. However, the spec... (Source: BMC Cardiovascular Disorders)
Source: BMC Cardiovascular Disorders - August 12, 2023 Category: Cardiology Authors: Nongnong Zhao, Zhengyang Yu, Zhejun Cai, Wenai Chen, Xiaopeng He, Zhaoxia Huo and Xiaoping Lin Tags: Research Source Type: research

Sex Related Differences in Electrocardiography
Physiol Res. 2023 Jul 31;72(Suppl 2):S127-S135.ABSTRACTSince its implementation into the clinical medicine by Willem Einthoven electrocardiography had become one of crucial diagnostic method in cardiology. In spite of this fact effects of gender differences on parameters of electrocardiographic recordings started to be studied only recently. Sex related differences in physiological ECG are only minimal in childhood but there are developing during adolescence reflecting rapidly evolving differences particularly in hormonal secretion and activity of an autonomic nervous system. The heart rate is approximately 7 % higher in w...
Source: Physiological Research - August 11, 2023 Category: Physiology Authors: O Kittnar Source Type: research

Sex Related Differences in Electrocardiography
Physiol Res. 2023 Jul 31;72(Suppl 2):S127-S135.ABSTRACTSince its implementation into the clinical medicine by Willem Einthoven electrocardiography had become one of crucial diagnostic method in cardiology. In spite of this fact effects of gender differences on parameters of electrocardiographic recordings started to be studied only recently. Sex related differences in physiological ECG are only minimal in childhood but there are developing during adolescence reflecting rapidly evolving differences particularly in hormonal secretion and activity of an autonomic nervous system. The heart rate is approximately 7 % higher in w...
Source: Cell Research - August 11, 2023 Category: Cytology Authors: O Kittnar Source Type: research

Sex Related Differences in Electrocardiography
Physiol Res. 2023 Jul 31;72(Suppl 2):S127-S135.ABSTRACTSince its implementation into the clinical medicine by Willem Einthoven electrocardiography had become one of crucial diagnostic method in cardiology. In spite of this fact effects of gender differences on parameters of electrocardiographic recordings started to be studied only recently. Sex related differences in physiological ECG are only minimal in childhood but there are developing during adolescence reflecting rapidly evolving differences particularly in hormonal secretion and activity of an autonomic nervous system. The heart rate is approximately 7 % higher in w...
Source: Physiological Research - August 11, 2023 Category: Physiology Authors: O Kittnar Source Type: research

Sex Related Differences in Electrocardiography
Physiol Res. 2023 Jul 31;72(Suppl 2):S127-S135.ABSTRACTSince its implementation into the clinical medicine by Willem Einthoven electrocardiography had become one of crucial diagnostic method in cardiology. In spite of this fact effects of gender differences on parameters of electrocardiographic recordings started to be studied only recently. Sex related differences in physiological ECG are only minimal in childhood but there are developing during adolescence reflecting rapidly evolving differences particularly in hormonal secretion and activity of an autonomic nervous system. The heart rate is approximately 7 % higher in w...
Source: Physiological Research - August 11, 2023 Category: Physiology Authors: O Kittnar Source Type: research

Calmodulin mutations can underlie the phenotype of long QT syndrome variant 1
J Physiol. 2023 Aug 9. doi: 10.1113/JP285220. Online ahead of print.NO ABSTRACTPMID:37555447 | DOI:10.1113/JP285220 (Source: The Journal of Physiology)
Source: The Journal of Physiology - August 9, 2023 Category: Physiology Authors: Robert S Kass Source Type: research

The Antiarrhythmic Action of the Na < sup > + < /sup > /Ca < sup > 2+ < /sup > Exchanger Inhibitor SEA0400 on Drug-Induced Long QT Syndrome Depends on the Severity of Proarrhythmic Conditions in Anesthetized Atrioventricular Block Rabbits
Biol Pharm Bull. 2023;46(8):1120-1127. doi: 10.1248/bpb.b23-00202.ABSTRACTTo clarify the pharmacological properties of the Na+/Ca2+ exchanger (NCX) inhibitor SEA0400 as an antiarrhythmic agent, we assessed its effects on rapid component of delayed rectifier K+ current (IKr) blocker-induced torsade de pointes (TdP) in isoflurane-anesthetized rabbits. Atrioventricular block was induced in rabbits using a catheter ablation technique, and the monophasic action potential (MAP) of the right ventricle was measured under electrical pacing at 60 beats/min. In non-treated control animals, intravenous administration of low-dose (0.3 ...
Source: Biological and Pharmaceutical Bulletin - August 2, 2023 Category: Drugs & Pharmacology Authors: Satoshi Kawakami Kazuhiro Takada Megumi Aimoto Yoshinobu Nagasawa Taichi Kusakabe Keisuke Kato Akira Takahara Source Type: research

The Antiarrhythmic Action of the Na < sup > + < /sup > /Ca < sup > 2+ < /sup > Exchanger Inhibitor SEA0400 on Drug-Induced Long QT Syndrome Depends on the Severity of Proarrhythmic Conditions in Anesthetized Atrioventricular Block Rabbits
Biol Pharm Bull. 2023;46(8):1120-1127. doi: 10.1248/bpb.b23-00202.ABSTRACTTo clarify the pharmacological properties of the Na+/Ca2+ exchanger (NCX) inhibitor SEA0400 as an antiarrhythmic agent, we assessed its effects on rapid component of delayed rectifier K+ current (IKr) blocker-induced torsade de pointes (TdP) in isoflurane-anesthetized rabbits. Atrioventricular block was induced in rabbits using a catheter ablation technique, and the monophasic action potential (MAP) of the right ventricle was measured under electrical pacing at 60 beats/min. In non-treated control animals, intravenous administration of low-dose (0.3 ...
Source: Biological and Pharmaceutical Bulletin - August 2, 2023 Category: Drugs & Pharmacology Authors: Satoshi Kawakami Kazuhiro Takada Megumi Aimoto Yoshinobu Nagasawa Taichi Kusakabe Keisuke Kato Akira Takahara Source Type: research

The Antiarrhythmic Action of the Na < sup > + < /sup > /Ca < sup > 2+ < /sup > Exchanger Inhibitor SEA0400 on Drug-Induced Long QT Syndrome Depends on the Severity of Proarrhythmic Conditions in Anesthetized Atrioventricular Block Rabbits
Biol Pharm Bull. 2023;46(8):1120-1127. doi: 10.1248/bpb.b23-00202.ABSTRACTTo clarify the pharmacological properties of the Na+/Ca2+ exchanger (NCX) inhibitor SEA0400 as an antiarrhythmic agent, we assessed its effects on rapid component of delayed rectifier K+ current (IKr) blocker-induced torsade de pointes (TdP) in isoflurane-anesthetized rabbits. Atrioventricular block was induced in rabbits using a catheter ablation technique, and the monophasic action potential (MAP) of the right ventricle was measured under electrical pacing at 60 beats/min. In non-treated control animals, intravenous administration of low-dose (0.3 ...
Source: Biological and Pharmaceutical Bulletin - August 2, 2023 Category: Drugs & Pharmacology Authors: Satoshi Kawakami Kazuhiro Takada Megumi Aimoto Yoshinobu Nagasawa Taichi Kusakabe Keisuke Kato Akira Takahara Source Type: research