II. Definition

  1. Sudden unexpected nocturnal death
  2. Includes only idiopathic cases of Sudden Cardiac Death

III. Epidemiology

  1. Incidence: Uncommon
    1. Accounts for <5% of Sudden Cardiac Death cases
  2. Family History of sudden death events often present
  3. Most common in men
  4. Greater Incidence in Southeast asia
    1. Northeastern Thailand (40/year per 100,000)
    2. Japan
    3. Philipines

IV. Pathophysiology

  1. J Wave Syndrome
  2. Inherited disorder of myocardial Sodium channels
  3. No structural abnormalities

V. Symptoms

  1. Often asymptomatic until terminal event (40%)
  2. Exertional Syncope history may be present
  3. Agonal Respirations may be present during sleep

VI. Diagnostics: EKG findings

  1. Prolonged QT Interval
  2. Right Bundle Branch Block
  3. Brugada Sign
    1. Seen best in the right precordial leads (V1-V3)
    2. End of QRS marked by significant upward deflection (J Point Elevation)
    3. ST Segment Elevation (leads v1-v3)
  4. Types
    1. Type 1 (coved-type, wide and large J Wave)
      1. Most concerning of the J Wave Patterns
      2. J-Wave amplitude >2 mm (or mV) at peak AND
      3. Followed by negative T Wave (minimal or no isoelectric component)
    2. Type 2 (saddleback pattern)
      1. J-Wave amplitude >2 mm (or mV) at peak AND
      2. ST Elevation >1 mm above baseline, gradually down-sloping AND
      3. Positive or biphasic T Wave
    3. Type 3
      1. Right precordial ST Elevation

VII. Diagnosis

  1. Shanghai Scoring System

VIII. Labs

  1. Genetic Test is available

IX. Management

  1. Symptomatic, type I Brugada morphology is most concerning
  2. Treatment Options
    1. Management decisions are based on symptomatic versus asymptomatic Brugada findings
    2. Internal Cardiac Defibrillator (ICD)
    3. Quinidine
  3. Exercise and sports participation are not contraindicated
    1. However avoid significant Hypothermia or hyperthermia
  4. Avoid provocative factors
    1. Treat fever
    2. No Cocaine
    3. Avoid excessive Alcohol

X. Complications

  1. Ventricular Tachycardia
  2. Cardiac Arrest with Ventricular Fibrillation
  3. Sudden Cardiac Death
    1. Mean age of onset 41 years old (but range of onset varies from newborns to elderly)

XI. Prognosis

  1. Mortality: 10% (without ICD placement)

Images: Related links to external sites (from Bing)

Related Studies