The Brugada syndrome is a genetic disease that is manifest by abnormal electrocardiogram (ECG) findings and an increased risk of sudden cardiac death. It is also known as Sudden Unexpected Death Syndrome¹ (SUDS), and is the most common cause of death in the young in Thailand and Laos². A genetic disorder, or genetic disease is a disease caused, at least in part, by the genes of the person with the disease. ... Lead II An electrocardiogram (ECG or EKG, abbreviated from the German Elektrokardiogramm) is a graphic produced by an electrocardiograph, which records the electrical voltage in the heart in the form of a continuous strip graph. ... A cardiac arrest is the cessation of normal circulation of the blood due to failure of the ventricles of the heart to contract effectively during systole. ...

First described in 1992³, the Brugada syndrome causes sudden death by causing ventricular fibrillation (a lethal arrhythmia) in the heart. 1992 (MCMXCII) was a leap year starting on Wednesday. ... Death is the cessation of physical life in a living organism, or the state of the organism after that event. ... Ventricular fibrillation (V-fib or VF) is a cardiac condition which consists of a lack of coordination of the contraction of the muscle tissue of the large chambers of the heart that eventually leads to the heart stopping altogether. ... A cardiac arrhythmia, also called cardiac dysrhythmia, is a disturbance in the regular rhythm of the heartbeat. ... The heart and lungs (from an older edition of Grays Anatomy) The heart (Latin cor) is a hollow, muscular organ in vertebrates that pumps blood through the blood vessels by repeated, rhythmic contractions, or a similar structure in annelids, mollusks, and arthropods. ...

Genetics and pathophysiology

Brugada syndrome is due to a mutation in the gene that encodes for the sodium ion channel in the cell membranes of the muscle cells of the heart (the myocytes). The gene, named SCN5A, is located on the short arm of the third chromosome (3p21). Gain-of-function mutations in this gene lead to elongation of the cardiac action potential. It is suspected that this occurs because the sodium channel isn't able to bind properly to ankyrin-G, an important protein mediating interaction between ion channels and cytoskeletal elements. This condition is inherited in an autosomal dominant pattern. This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... General Name, Symbol, Number sodium, Na, 11 Chemical series alkali metals Group, Period, Block 1, 3, s Appearance silvery white Atomic mass 22. ... Another, unrelated ion channeling process is part of ion implantation. ... Cells in culture, stained for keratin (red) and DNA (green). ... It has been suggested that Net flux be merged into this article or section. ... Myocyte is the technical term for a muscle cell. ... Figure 1: Chromosome. ... An autosomal dominant gene is an abnormal gene on one of the autosomal (non-sex determining) chromosomes. ...

Electrocardiography

In some cases, the disease can be detected by observing characteristic patterns on an electrocardiogram, which may be present all the time, or might be elicited by the administration of particular drugs. The pattern seen on the ECG is persistent ST elevations in the electrocardiographic leadsV₁-V₃ with a right bundle branch block (RBBB) appearance with or without the terminal S waves in the lateral leads that are associated with a typical RBBB. A prolongation of the PR interval (a conduction disturbance in the heart) is also frequently seen. Lead II An electrocardiogram (ECG or EKG, abbreviated from the German Elektrokardiogramm) is a graphic produced by an electrocardiograph, which records the electrical voltage in the heart in the form of a continuous strip graph. ... Right bundle branch block (RBBB) is a cardiac conduction abnormality seen on electrocardiogram (EKG). ...

Treatment

The cause of death in Brugada syndrome is ventricular fibrillation. While there is no treatment modality that prevents ventricular fibrillation from occurring in this syndrome, treatment lies in termination of this lethal arrhythmia before it causes death. This is done via implantation of an implantable cardioverter-defibrillator (ICD), which continuously monitors the heart rhythm and will defibrillate an individual if ventricular fibrillation is noted. Those with risk factors for coronary artery disease may require an angiogram before ICD implantation. Ventricular fibrillation (V-fib or VF) is a cardiac condition which consists of a lack of coordination of the contraction of the muscle tissue of the large chambers of the heart that eventually leads to the heart stopping altogether. ... A cardiac arrhythmia, also called cardiac dysrhythmia, is a disturbance in the regular rhythm of the heartbeat. ... An implantable cardioverter-defibrillator (ICD) is a device that is implanted under the skin of patients that are at risk of sudden death due to ventricular fibrillation. ... Typical view of the defibrillator operator. ... Coronary heart disease (CHD), also called coronary artery disease (CAD) and atherosclerotic heart disease, is the end result of the accumulation of atheromatous plaques within the walls of the arteries that supply the myocardium (the muscle of the heart). ...

See also

• Cardiac action potential
• Genetics
• Ion channel
• Tambocor

The cardiac action potential is the electrical activity of the individual cells of the electrical conduction system of the heart. ... Genetics (from the Greek genno γεννώ= give birth) is the science of genes, heredity, and the variation of organisms. ... Another, unrelated ion channeling process is part of ion implantation. ... Flecainide acetate is a class Ic antiarrhythmic agent used to prevent and treat tachyarrhythmias (abnormal fast rhythms of the heart). ...

References

1. Hong K, Berruezo-Sanchez A, Poungvarin N, Oliva A, Vatta M, Brugada J, Brugada P, Towbin JA, Dumaine R, Pinero-Galvez C, Antzelevitch C, Brugada R. Phenotypic characterization of a large European family with Brugada syndrome displaying a sudden unexpected death syndrome mutation in SCN5A. J Cardiovasc Electrophysiol. 2004 Jan;15(1):64-9. PMID 15028074
2. Brugada J, Brugada P, Brugada R. The syndrome of right bundle branch block ST segment elevation in V1 to V3 and sudden death--the Brugada syndrome. Europace. 1999 Jul;1(3):156-66. PMID 11225790
3. Brugada P, Brugada J. Right bundle branch block, persistent ST segment elevation and sudden cardiac death: a distinct clinical and electrocardiographic syndrome. A multicenter report. J Am Coll Cardiol. 1992 Nov 15;20(6):1391-6. PMID 1309182

External links

• Graham-Rowe: "Death in the Family", New Scientist 20 Sept. 2002
• Algado et al: http://www.medspain.com/ant/n13_jun00/Brugada.htm
• Behr: http://www.c-r-y.org.uk/long_qt_syndrome.htm
• OMIM 601144
• OMIM 600163
• The Ramon Brugada Senior Foundation