Syndrome of Romano-Ward

The syndrome of Romano-Ward is a hereditary disorder of cardiac operation, whereas the anatomy of the heart is strictly normal. It often appears at subjects by syncopes being able to lead to a death subite.
the treatment is medical and efficace.
De many drugs are formally contra-indicated at these patients

Etiology

Several genes are implied in this syndrome. The changes of these various genes lead all to a dysfunction of the cardiac ionic Canaux either potassic or sodic
potassic Canaux
Mutation of the Gène KCNQ1 located at the level of the Locus p15.5 of the Chromosome 11
Mutation of the Gène KCNE1 located at the level of the Locus q22.1-q22.2 of the Chromosome 21
Mutation of the Gène KCNH2 located at the level of the Locus q35-q36 of the Chromosome 7
Mutation of the Gène KCNE2 located on the level of the Locus q22.1 of the Chromosome 21
sodic Canaux
Mutation of the Gène SCN5A located at the level of the Locus p21 of the Chromosome 3
Of other genes probably implied:
Change of the Gene KCNJ2 located at the level of the Locus q23.1-q24.2 of the Chromosome 17
Change of the Gene ANK2 located at the level of the Locus q25-q27 of the Chromosome 4

Description

All the people presenting the changes of genes will not always have clinical demonstrations, but the sudden death occurs at 10% of the people with demonstration clinique.
The demonstrations of this disease generally start during puberty but sometimes it appears very early. This disease appears by anomalies of the involving cardiac rhythm of the anomalies of the contraction of the ventricles or Torsades of point involving syncopes which occur without starting cause. These syncopes occur brutally without warning. This syncope is often diagnosed like a crisis of epilepsy
Sometimes the twists of point involve ventricular fibrillations responsible for cardiac arrest with died in the absence of treatment
The events being able to involve the twists of point are the excitations, the emotions, anger, a fear, tears, stress, noises strident, a ringing of telephone, clock alarm, horn, medical examinations, pains etc…. Sometimes the disease appears by a death during the sleep.

Diagnosis

By measurement of interval QT or the description of a change.

E.C.G

Is made on the basis of measurement of the interval QT during the electrocardiogram, the QT is known as length if time between the beginning of the wave Q and the end of the wave T of the electrocardiogram is of 450 milliseconds . The diagnosis is posed if interval QT is of 470 milliseconds at the men and 480 milliseconds at the femmes
However in 30% of the cases the interval is prolonged little and in 10% of the cases the interval is normal. In this case, it is necessary to carry out tests of provocation in specialized centres in the disorders of the rate/rhythm cardiaque.
The analysis of the form of the wave T also makes it possible to make the diagnosis in certain cases and to differentiate the various types of this syndrome

Genetics

Only 70% of the people reached have a change of the genes KCNQ1 , KCNE1 , KCNH2 , KCNE2 and SCN5A indicating that other genes are implied

Differential diagnosis

Syndrome of Romano-Ward with syndactylie
Syndrome of Jervell and Lange-Nielsen
Syndrome of the acquired long QT
Syndrome of Andersen-Tawil
All the other causes of syncope or sudden death can be discussed.

The genetic Council

The patients reached by this disease have a relative carrying gene. It will be necessary to seek by the same diagnostic tests the relative reached. The changes of novo being very rare, it will be necessary to think of a different parent or a hidden adoption.

Sources

Site in French of information on the orphan rare diseases and drugs
Site on the long QT
Site in English Impossible to circumvent for the genetic diseases
G Michael Vincent, Romano-Ward Syndrome in GeneReviews At GeneTests: Medical Genetics Information Resource (database online). Copyright, University off Washington, Seattle. 1997-2007. * Drugs and long QT

Romano-Ward

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