The congenital long QT syndrome (LQTS) is a genetic cardiac channelophathy with variable penetrance characterized by corrected QT (QTc) interval prolongation and predisposition to polymorphic ventricular tachycardia (PVT), which normally presents with syncope or sudden death. It can be caused by mutations in different ion channels, resulting in prolongation of the myocardial repolarization1. Th...

A single 400 mg dose of moxifloxacin has been the standard positive control for thorough QT (TQT) studies. However, it is not clearly known whether a 400 mg dose is also applicable to TQT studies in Asian subjects, including Koreans. Thus, we aimed to develop a pharmacokinetic (PK)-pharmacodynamic (PD) model for moxifloxacin, to evaluate the time course of its effect on QT intervals in Koreans....

Background: Although QT prolongation is associated with increased risk of torsade de pointes (TdP), the precise relationship is not well defined. Aim: To evaluate the performance of a QT nomogram in assessing the risk of TdP from QT– RR combinations. Design: Systematic review. Methods: We systematically searched MEDLINE/ EMBASE for cases of drug-induced TdP. Controls were patients taking non-ca...

The Comprehensive in vitro Proarrhythmia Assay (CiPA) initiative is developing and validating a mechanistic-based assessment of the proarrhythmic risk of drugs. CiPA proposes to assess a drug's effect on multiple ion channels and integrate the effects in a computer model of the human cardiomyocyte to predict proarrhythmic risk. Unanticipated or missed effects will be assessed with human stem ce...

Anti-arrhythmic drugs such as amiodarone have the potential to prolong QT intervals, which can result in torsades de point arrhythmia. It is unknown whether amiodarone, given to a recipient prior to cardiac transplantation, can cause arrhythmia in a newly transplanted donor heart. We report on a case of a 71-year-old male patient who had received intravenous and oral amiodarone prior to transpl...

BACKGROUND Cases of QT prolongation, torsades de pointes, and sudden death have been reported with arsenic trioxide (As2O3), a highly effective agent for acute promyelocytic leukemia. In this study, we evaluated the effects of As2O3 on repolarizing cardiac ion currents. METHODS AND RESULTS In HERG- or KCNQ1+KCNE1-transfected CHO cells (n=32; total), As2O3 caused concentration-dependent block ...

BACKGROUND AND PURPOSE Early identification of patients at risk of angiographic vasospasm after aneurysmal subarachnoid hemorrhage (SAH) may mitigate its sequelae. One mechanism that may contribute to angiographic vasospasm is increased central sympathetic activity, which is also thought to cause electrocardiographic (ECG) changes after SAH. Here, we perform the first study to determine the ass...

BACKGROUND Although QT prolongation is associated with increased risk of torsade de pointes (TdP), the precise relationship is not well defined. AIM To evaluate the performance of a QT nomogram in assessing the risk of TdP from QT-RR combinations. DESIGN Systematic review. METHODS We systematically searched MEDLINE/EMBASE for cases of drug-induced TdP. Controls were patients taking non-ca...

The authors report an early occurrence (within 48 hours) of the newly described form of pause-dependent torsade de pointes following acute myocardial infarction. QT prolongtion after myocardial infarction a common ECG finding. Postextrasystolic QT prolongation rare but one of the warning signs for torsade de pointes ventricular tachycardia following myocardial infarction. Careful monitoring is ...