Brugada syndrome

Background

• Consider as cause of syncope in patients with family history of sudden death
• 80% of Brugada syndrome diagnosed only after a cardiac arrest
• Autosomal dominant Na-channelopathy which increases the risk of sudden cardiac death (~10%/yr)
• Much more common in men (up to 9x), particularly Southeast Asian males
• ECG shows incomplete RBBB with ST elevation in V1-V3
  • In uncomplicated RBBB, usually there no ST change to slight ST depression
  • If presenting symptom is chest pain rather than syncope, consider strongly STEMI

Clinical Features

• Typically asymptomatic
• ECG findings can be more prominent during times of illness or fever
• Patients may have Vfib arrest or sudden death

Differential Diagnosis

ST Elevation

• Cardiac
  • ST-segment elevation myocardial infarction (STEMI)
  • Post-MI (ventricular aneurysm pattern)
  • Previous MI with recurrent ischemia in same area
  • Wellens' syndrome
  • Coronary artery vasospasm (eg, Prinzmetal's angina)
  • Coronary artery dissection
  • Pericarditis
  • Myocarditis
  • Aortic dissection in to coronary
  • Left ventricular aneurysm
  • Left ventricular pseudoaneurysm
  • Early repolarization
  • Left bundle branch block
  • Left ventricular hypertrophy (LVH)
  • Myocardial tumor
  • Myocardial trauma
  • RV pacing (appears as Left bundle branch block)
  • Brugada syndrome
  • Takotsubo cardiomyopathy
  • AVR ST elevation
• Other thoracic
  • Pneumomediastinum
  • Pneumothorax
  • Pulmonary embolism
• Metabolic
  • Drugs of abuse (eg, cocaine, crack, meth)
    • Cocaine chest pain
  • Hyperkalemia (only leads V1 and V2)
  • Hypothermia ("Osborn J waves")
• Medications
  • Tricyclic (TCA) toxicity
  • Digoxin

Evaluation

ECG Criteria

Note - ECG findings can be transient

• Type 1-Elevated ST segment (>2mm) descends with upward convexity to a TWI
• Type 2-Elevated ST segment (>1mm) descends toward baseline then rises again (saddleback) to upright T wave
• Type 3-Elevated ST segment (<1mm) descends toward baseline then rises again to upright T wave

Management

• Cardiology consultation

Disposition

• Needs EP consult and VF-inducing electrophysiologic study (EPS), though EPS is controversial prognosticator
• Inpatient vs outpatient ICD placement
  • Prophylactic ICDs may have risks of complications greater than benefits conferred
  • Mortality around 10% per year without ICD placement^{[citation needed]}
  • Antidysrhythmics have no effect on prognosis

External Links

• Amal Mattu ECG Case: March 4 2012

See Also

• ST elevation