Post on 14-Dec-2015
Brugada’s Syndrome and Sudden Cardiac Death
Petra Lovrec
Brugada’s Syndrome and Sudden Cardiac Death
Petra LovrecMentor: A. Žmegač Horvat
Sudden Cardiac Death
Incidence
(cases/year)
Survival
Worldwide 3 000 000 ‹1%
U.S. 450 000 5%
W. Europe 400 000 ‹5%
Cardiomyopathy
• dilated cardiomyopathy
• hypertrophic cardiomyopathy
• arrythmogenic right ventricular cardiomyopathy
• left ventricular non-compaction
• restrictive cardiomyopathy
Cardiac Chanellopathies
• Brugada syndrome
• long QT syndrome
• short QT syndrome
• idiopathic VF
• short coupled Torsades
Brugada Syndrome
• first described in 1992 in 8 patients with aborted sudden cardiac death
• history since 1986 – Brugada brothers
Brugada Syndrome
• characterized by:– ECG findings of RBBB and persistent ST
elevation in V1 – V3– structurally normal hearts– propensity for life-threatening ventricular
arrhythmias– J point elevation
Brugada Syndrome: ECG
Typical electrocardiogram of Brugada syndrome. Note the pattern resembling a right bundle branch block,the P-R prolongation and the ST elevation in leads V1-V3.
Brugada Syndrome: ECG
Spontaneous polymorphic ventricular tachycardia recordedduring monitoring in a patient with Brugada syndrome.The arrhythmias are fast and need DC shock to terminate.
Brugada Syndrome: Clinical Features
• unexpectad sudden death
• syncope, seizures
• agonal nocturnal respirations
• affects male patients predominantly (8:1)
• cases reported worldwide
Brugada Syndrome: Incidence and Distribution
• responsible for up to 50% of sudden death victims with structurally normal hearts in Thailand
• recognized in Asia for decades:– Philippines: Bangungut = scream followed by
sudden death during sleep– Thailand: Lai tai = death during sleep– Japan: Pokuri = unexpected death during
sleep
Brugada Syndrome: ECG
12-lead ECG during administration of ajmaline (50 mg in 5 min). Note the progressive appearance of the ST elevation in V1-V3.
Brugada Syndrome: Factors / Drugs that Enhance ECG Pattern
• Na+ channel blockers
• alpha agonists, vagotonic agents, beta blockers
• fever
• alcohol, cocaine
• severe ischemia
• tricyclic antidepressants, antihistaminics
Brugada Syndrome: Genetics
• autosomal dominant• 60 different mutations in the SCN5A
(chromosome 3) gene have been linked to the syndrome
• failure of alpha subunit of sodium channel to express
• shift in voltage and time dependence on I(Na+) activation, inactivation or reactivation
Brugada Syndrome: Diagnosis
• symptoms: syncope, SCD (usually during sleep)• physical exam: normal• family history: strong history of SCD• ECG: best test to identify Brugada patients
– may require Flecainide or Procainamide to bring out typical findings
– ST elevation, RBBB
• imaging tests: usually no underlying structural disease
• stress tests: symptoms and ECG findings not usually reproducible with exercise
Brugada Syndrome: Diagnostic Criteria
• major criteria:– 1. presence of ECG marker in structurally normal
hearts– 2. appearance of ECG marker after administration of
Na+ channel blockers
• minor criteria:– 1. family history of sudden cardiac death– 2. syncope of unknown origin– 3. documented ventricular tachycardia/fibrillation– 4. genetic mutation of ion channels
Brugada Syndrome: Treatment
• IMPLANTABLE CARDIOVERTER-DEFIBRILLATOR (ICD)
• symptomatic with the disease: ICD• asymptomatic with family history of SCD: with normal
ECG – OBSERVE• asymptomatic with prolonged H-V interval and inducible
VT/VF: controversial ICD
Potential Antiarrhythmic Drugs in Brugada Syndrome
• Quinidine (non specific I blocker)
• Isoproterenol (open L type calcium channel)
• Cilostazol (augment I Ca)
Conclusion
• sudden cardiac death in Southeast Asia
• characteristic ECG pattern – ST elevation in V1 – V3
• ICD implantation in symptomatic patients