Na+ channel mutation leading to loss of function and non-progressive cardiac conduction defects.

Background: We previously described a Dutch family in which congenital cardiac conduction disorder has clinically been identified. The ECG of the index patient showed a first-degree AV block associated with extensive ventricular conduction delay. Sequencing of the SCN5A locus coding for the human cardiac Na+ channel revealed a single nucleotide deletion at position 5280, resulting in a frame-shift in the sequence coding for the pore region of domain IV and a premature stop codon at the C-terminus.

A novel LQT3 mutation implicates the human cardiac sodium channel domain IVS6 in inactivation kinetics.

Unlabelled: The Long QT3 syndrome is associated with mutations in the cardiac sodium channel gene SCN5A.

Objective: The aim of the present study was the identification and functional characterization of a mutation in a family with the long QT3 syndrome.

Methods: The human cardiac sodium channel gene SCN5A was screened for mutations by single-stranded conformation polymorphism.

Implantable diagnostic and therapeutic devices in children.

Many advances have been made in the use of implantable diagnostic and therapeutic devices in adults. In children the indications for and diagnostic and therapeutic value of these devices still have to be determined. Our aim is to provide an overview of the clinical use of diagnostic and therapeutic devices in children.

Absence of calsequestrin 2 causes severe forms of catecholaminergic polymorphic ventricular tachycardia.

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare arrhythmogenic disorder characterized by syncopal events and sudden cardiac death at a young age during physical stress or emotion, in the absence of structural heart disease. We report the first nonsense mutations in the cardiac calsequestrin gene, CASQ2, in three CPVT families. The three mutations, a nonsense R33X, a splicing 532+1 G>A, and a 1-bp deletion, 62delA, are thought to induce premature stop codons.

Catheter ablation of incisional atrial tachycardia using a novel mapping system: LocaLisa.

Incisional atrial tachycardia occurs due to reentry around surgical scars. Pharmacological therapy is often ineffective. This study assessed the efficacy of a novel mapping system (LocaLisa) in facilitating catheter ablation of incisional atrial tachycardia circuits.