ST Elevation

Aka: ST Elevation, ST-Segment Elevation, ST Segment Elevation

1. See Also
   1. Electrocardiogram in Myocardial Infarction
   2. ST Segment
   3. Electrocardiogram
2. 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)
3. Causes: General
   1. Acute Myocardial Infarction
      1. See Electrocardiogram in Myocardial Infarction
      2. Type A Aortic Dissection may also cause Coronary Artery dissection (esp. right Coronary Artery)
   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
         1. See Hyperkalemia Related EKG Changes
         2. ST Depression is more common
         3. Associated with Wide QRS, Bradycardia, Peaked T Waves
      3. Neurologic catastrophe (e.g. Subarachnoid Hemorrhage)
      4. Pulmonary Embolism
      5. Wolff-Parkinson-White Syndrome (WPW Syndrome)
      6. Tricyclic Antidepressant Overdose
      7. Brugada Syndrome
      8. Global Myocardial Ischemia
      9. Left Ventricular aneurysm
         1. LV Aneurysm is a complication following Myocardial Infarction
         2. Diffuse ST Elevation without reciprocal changes
4. Causes: Diffuse ST Elevation
   1. Large acute Myocardial Infarction
   2. Acute Pericarditis
      1. See EKG in Pericarditis
      2. Other findings include PR Segment Depression and downsloping
   3. Benign Early Repolarization
   4. Left Ventricular Hypertrophy
      1. See Left Ventricular Hypertrophy Related EKG Changes to calculate voltage criteria
5. References
   1. DeMeester and Swaminathan in Swadron (2022) EM:Rap 22(8): 9-10
   2. Mattu (2022) Crit Dec Emerg Med 36(8): 13
   3. Wang (2003) N Engl J Med 349:2128-35 [PubMed]