Exam

ST Elevation

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ST Elevation, ST-Segment Elevation

  • Measurement
  1. Measure at 0.04 sec (1 mm) after the J-Point
  2. Compare to baseline (line drawn from P start to T end)
  • Causes
  1. Acute Myocardial Infarction
    1. SEE EKG changes in acute MI
  2. Pericarditis
    1. Diffuse ST Elevation
  3. Left Bundle Branch Block
    1. Findings
      1. Left Bundle Branch Block in lead V1
      2. QRS Duration > 120 ms
      3. QRS Complex negative (down) in V1
    2. Left ventricular activation delay
      1. Hides ST segment elevation
      2. Evaluate new LBBB as Acute Coronary Syndrome
  4. Pacemaker with paced beats from right ventricle
    1. Left Bundle Branch Block in V1 with pacer spike
    2. Not possible to diagnose Acute MI
  5. Left Ventricular Hypertrophy
    1. Increased QRS Complex amplitude
    2. ST segment elevation/depression in precordial leads
    3. T Wave direction opposite to QRS Complex
    4. Not possible to diagnose Acute MI
  6. Early Repolarization
    1. More common in black men, young and athletes
    2. Concave upwards (smiley) elevation
  7. Other causes
    1. Prinzmetal's Angina
    2. Hyperkalemia
    3. Neurologic catastrophe (e.g. Subarachnoid Hemorrhage)
  • References
  1. Wang (2003) N Engl J Med 349:2128-35 [PubMed]