Objective—To determine the normal values of QT and QTc dispersion and the eVects of sinus arrhythmia on QT dispersion in healthy children. Patients and setting—The study was carried out in a university hospital on 372 local schoolchildren (200 male, 172 female), aged seven to 18 years. Methods—The QT and preceding RR intervals of at least one sinus beat were measured manually in a range of nine...

Among childhood psychiatric disorders, attention deficit hyperactivity disorder (ADHD) is of greatest interest to practitioners. Methylphenidate (MPH) is a drug that is widely used in the treatment of children in whom ADHD has been diagnosed. Although this treatment has been used for years, its effects on the heart remain the subject of debate. The QT interval comprises the ventricular activati...

Clinicians are well aware that responses to QT-prolonging drugs vary among individuals.1 A drug dose (and concentration) that produces minimal QT prolongation in one patient may, in an apparently indistinguishable subject, produce marked QT prolongation and torsade de pointes. This variability in response to an exogenous stressor is paralleled by variability in the extent to which a given mutat...

We study the transverse-momentum (qT ) and rapidity (y) distributions of the Higgs boson in perturbative QCD, including the most advanced theoretical information presently available: fixed-order perturbation theory at Next-to-Leading Order (NLO) in the large-qT region (qT ∼ MH , being MH the Higgs mass), and soft-gluon resummation at the Next-to-Next-to-Leading Logarithmic accuracy (NNLL) in th...

Long QT syndrome is associated with lethal tachyarrhythmia that can lead to syncope, seizure, and sudden death. Congenital long QT syndrome is a genetic disorder, characterized by delayed cardiac repolarization and prolongation of the QT interval on the electrocardiogram (ECG). Type 2 congenital long QT is linked to mutations in the human ether a go-go-related gene (HERG). There are environment...

We propose a simplified version of the Qt framework, called as Qt Operational Model, which is integrated into the Efficient SMT-based Context-Bounded Model Checking tool, for verifying actual Qt-based applications. Experimental results show that our proposed approach can be effectively and efficiently applied to verify Qt-based real-world applications from consumer electronics.

introduction: prolongation of qt interval might result in dangerous cardiac arrhythmias, including torsades de pointes (tdp), consequently leading to syncope or death. a limited number of studies carried out in this respect to date have shown that qt interval might increase during pregnancy. on the other hand, it has been shown that each pregnancy might result in an increase in the risk of card...

BACKGROUND Automatic measurement becomes a preference, and indeed a necessity, when analyzing 1000 s of ECGs in the setting of either drug-inducing QT prolongation screening or genome-wide association studies of QT interval. The problem is that individual manufacturers apply different computerized algorithms to measure QT interval. We conducted a comparative study to assess the outcomes with di...

OBJECTIVES The purpose of this study was to evaluate the efficacy of various antiarrhythmic drugs at prolonging the QT interval into the normal range and preventing ventricular arrhythmias in patients with short QT syndrome. BACKGROUND Short QT syndrome is a recently described genetic disease characterized by short QT interval, high risk of sudden death, atrial fibrillation, and short refract...

AIMS Repolarization has rate-dependent and rate-independent components. A function considering such components separately was validated in canine Purkinje fibres and applied to the QT/RR relation in humans. METHODS AND RESULTS Action potential duration (APD) was measured in Purkinje fibres during steady-state pacing at different cycle lengths (CL) and after prolonged quiescence (APD(0)). The ...