QT Interval Variability and Adaptation to Heart Rate Changes in Patients with Long QT Syndrome

KCNE1 and KCNE2 variants in Patients with Long QT Syndrome

Introduction: Long QT syndrome (LQTS) is a type of ventricular arrhythmia characterized by prolonged QT intervals on electrocardiogram or delay in ventricular repolarization and it can lead to syncope, seizure and sudden cardiac death. Here, KCNE1 and KCNE2 variants are studied among Iranian affected families with this syndrome. Materials and Methods: Fifty patients referring to Rajaei Cardiov...

QT Adaptation and Intrinsic QT Variability in Congenital Long QT Syndrome

BACKGROUND Increased variability of QT interval (QTV) has been linked to arrhythmias in animal experiments and multiple clinical situations. Congenital long QT syndrome (LQTS), a pure repolarization disease, may provide important information on the relationship between delayed repolarization and QTV. METHODS AND RESULTS Twenty-four-hour Holter monitor tracings from 78 genotyped congenital LQT...

QT Interval and QT Variability

Rate adaptation of QT intervals during and after exercise in children with congenital long QT syndrome.

OBJECTIVES To improve the diagnostic criteria of the congenital long QT syndrome in borderline cases we examined rate adaptation of ventricular repolarization phases during exercise and subsequent recovery in children with the long QT syndrome and controls. METHODS Nineteen children with definite long QT syndrome and 19 healthy controls underwent exercise testing. QT intervals were measured t...

[The long QT interval syndrome].

The syndrome of long QT interval frequently follows to syncope or a sudden cardiac death on the basis of originated polymorphic ventricular tachycardia of the "torsade de pointes" type. The prolongation of the QT interval in the hereditary form is based on mutation of the genes responsible for the formation of sodium and potassium channels. The authors analyze the occurrence, clinical findings,...