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.

Neurophysiological effects of pediatric balloon dilatation procedures.

Balloon dilatation of valvar and vascular stenoses has become routine therapy in pediatric cardiology. Repeated balloon inflations cause many episodes of low cerebral oxygen delivery. This study is a prospective study to assess the effects of balloon dilatation on cerebral perfusion and oxygenation.

[Implantable ECG recorder revealed the diagnosis in a baby with apparent life-threatening events].

A 14-month-old boy went through episodes of cyanosis and brief loss of consciousness. Extensive investigations failed to lead to a diagnosis, until an implanted ECG recorder revealed ECG abnormalities suggestive of strangulation. Interviews with the father and mother showed that this was indeed the case.

Homozygous premature truncation of the HERG protein : the human HERG knockout.

Background-In long-QT syndrome (LQTS), heterozygosity for a mutation in 1 of the K(+) channel genes leads to prolongation of the cardiac action potential, because the aberrant protein exhibits "loss of function." HERG, which is involved in LQT2, is the gene encoding the rapid component of the delayed rectifier, I(Kr). Methods and Results-In a consanguineous family, a stillbirth was followed by the premature birth of a child in distress due to ventricular arrhythmia in the presence of QT prolongation.

Clinical, pathological and molecular genetic findings in a case of neonatal Marfan syndrome.

An infant with neonatal Marfan syndrome is described who presented with arachnodactyly, distinctive dysmorphic features and prolapse of both atrioventricular valves and dilatation of both the aortic and pulmonary root. She died in cardiac failure shortly after pacemaker implantation, due to dysrhythmia and severe mitral insufficiency. At autopsy, apart from myxomatous changes of the valves and dilated aortic and pulmonary roots, an aneurysm of the sinus of Valsalva of the pulmonary valve and abnormal myxomatous connective tissue surrounding the AV node were also found.

Alagille syndrome in a family with duplication 20p11.

Alagille syndrome (arteriohepatic dysplasia, AHD) is a well defined genetic disorder with five major features: distinctive facies, cardiovascular anomalies, paucity of interlobular bile ducts (PILBD), ocular anomalies and minor skeletal malformations. Repeatedly, structural anomalies of 20p, in most cases a deletion, have been described in patients with Alagille syndrome. We report a three generation family with AHD presenting with typical facial dysmorphology, cardiac and ocular lesions but without clinical signs of liver manifestation.

Deletion of the long arm of chromosome 6: two new patients and literature review.

Two children with a partial monosomy 6q are reported: a girl with an interstitial deletion [46,XX,del(6)(q16.2q23.1)], and a boy with a terminal deletion [46,XY,del(6)(q25.

Sedation for children undergoing magnetic resonance imaging: efficacy and safety of rectal thiopental.

Unlabelled: The need to reappraise sedation policy is dictated by newer noninvasive imaging modalities. In this study we evaluate the safety and efficacy of rectally-administered thiopental in children undergoing MRI. Eighty-three consecutive patients with congenital heart disease (mean age 2.

Air travel and adults with cyanotic congenital heart disease.

Background: Concern has been expressed that a reduction of partial oxygen pressure during flight in commercial aircraft may induce dangerous hypoxemia in patients with cyanotic congenital heart disease.

Methods And Results: To evaluate the validity of this concern, the transcutaneous SaO2 was measured in 12 adults with this type of heart disease and 27 control subjects during simulated commercial flights of 1.5 and 7 hours in a hypobaric chamber.

[Proteus syndrome. Expansion of the phenotype. Apropos of 3 pediatric cases].

In 1979 Cohen et Hayden and in 1983 Wiedemann et al. delineated a syndrome consisting of partial gigantism of the hands and/or feet, nevi, hemihypertrophy, subcutaneous tumors, macrocephaly or other skull anomalies and possible accelerated growth and visceral affections. Hitherto the literature pertaining to this syndrome consists of somewhat more than 100 cases of which some, that have been described previously or subsequently under other headings, were rediagnosed as being Proteus syndromes.

Vanishing calcification of the brain in an infant after open heart surgery.

Neurological complications after cardiac operations with the aid of cardiopulmonary bypass and hypothermia are well known. A 6 months-old child is described with severe neurological complications after cardiac surgery for Fallot's tetralogy. On the CT scan cortical calcification was seen to vanish.