Cardiac Electrophysiology

Cardiac Electrophysiology

Information Covered:

  1. Electrophysiology
    1. Characteristics of myocardial cells
      1. Automaticity
      2. Excitability
      3. Conductivity
      4. Contractility
    2. Electrical potential
      1. Action potential – important electrolytes
        1. Sodium
        2. Potassium
        3. Calcium
        4. Chloride
        5. Magnesium
      2. Excitability
        1. Thresholds
        2. Depolarization
        3. Repolarization
          1. relative refractory period
          2. absolute refractory period
      3. Neurotransmitters
        1. Acetycholine
          1. effects on myocardium
          2. effects on systemic blood vessels
        2. Cholinesterase
          1. effects on myocardium
          2. effects on system blood vessels
  2. Electrocardiographic (ECG) monitoring
    1. Electrophysiology and wave forms
      1. Origination
      2. Production
      3. Relationship of cardiac events to wave forms
      4. Intervals
        1. Normal
        2. Clinical significance
      5. Segments
    2. Leads and electrodes
      1. Electrode
      2. Leads
        1. Anatomic positions
        2. Correct placement
      3. Surfaces of heart and lead systems
        1. Inferior
        2. Left lateral
        3. Anterior/ posterior
      4. Artifact
    3. Standardization
      1. Amplitude
      2. Height
      3. Rate
        1. Duration
        2. Wave form
        3. Segment
        4. Complex
        5. Interval
    4. Wave form analysis
      1. Isoelectric
      2. Positive
      3. Negative
      4. Calculation of ECG heart rate
        1. Regular rhythm
          1. ECG strip method
          2. "300"/triplicate method
        2. Irregular rhythm
          1. ECG strip method
          2. "300"/triplicate method
    5. Lead systems and heart surfaces
      1. ECG rhythm analysis
        1. Value
        2. Limitations
      2. Heart surfaces
        1. Inferior
        2. Left lateral
        3. Precordial
      3. Acute signs of ischemia, injury and necrosis
        1. Rationale
          1. possible early identification of patients with acute myocardial infarction for intervention (thrombolysis PTCA)
          2. the role of out-of-hospital 12-lead ECG is not universally available but is appropriate in most EMS settings with proper medical oversight
        2. Advantages/ disadvantages
        3. ST segment elevation
          1. height, depth and contour
          2. ST (acute changes)
            1. anterior wall -- significant ST elevation in V1- V4 may indicate anterior involvement
            2. inferior wall -- significant ST elevation in II, III and aVF may indicate inferior involvement
          3. ST segment depression in eight or more leads
          4. ST segment elevation in aVR and V1
        4. Q waves
          1. depth, duration and significance
            1. greater than 5 mm, greater than .04 seconds
            2. may indicate necrosis
            3. may indicate extensive transient ischemia

 

Content Creator: Bridget Kammerzelt

CAPCE Course Number: 17-EMTP-F3-7206

Total CE Hours: 1.25

Level: Advanced

EMT-CE uses the NEMSES guidelines as the foundation for every course outline.