Brugada Syndrome
· ECG changes found in .4% of asymptomatic people in the USA. Much higher in Southeast Asian populations.
· 4 to 5% of sudden cardiac deaths, predominantly those occurring at night and in young people. Males predominate.
· 50% have an identified genetic component – probably a sodium channel gene.
· 20% of cardiac arrests where the heart is structurally normal.
· Most people are asymptomatic
· Commonest presentation is syncope or sudden death. Chest pain is not common.
· Atrial fibrillation is more likely to occur. Think about this diagnosis.
· Pre-terminal rhythms most commonly polymorphic or monomorphic ventricular tachycardia leading to ventricular fibrillation.
· Common contributor to cocaine-induced arrhythmias.
· Possibly triggered by any drug blocking sodium channels including tricyclic overdose, psychotropics, flecanide and procainamide.
ECG Findings: (see Figure)
· Polymorphic or monomorphic ventricular tachycardia when symptomatic.
· Asymptomatic patients – usually changes in V1, V2, and sometimes V3. Pseudo RBBB pattern (not seen in limb leads) with convex or concave ST elevation and no reciprocal findings.
ECG findings plus at least 1 of the following:
· Documented ventricular fibrillation
· Self-terminating polymorphic ventricular tachycardia (VT)
· Family history of sudden cardiac death at <45 years
· Type 1 ST segment elevation in family members
· Electrophysiologic inducibility of VT
· Unexplained syncope suggestive of a tachyarrhythmia
· Nocturnal agonal respiration
· Symptomatic – cardioversion or defibrillation based on ECG. If polymorphic ventricular tachycardia remember to use unsynchronized shocks at 200-360 joules.
· Asymptomatic – refer quickly for electrophysiologic testing. Avoid drugs which block sodium channels. Most patients require and implantable cardioverter-defibrillator.
· Audio – Digest Emergency Medicine 2007. Vol 24(1)
· UpToDate Ver. 14.2 2006. Brugada syndrome and sudden cardiac death.
