10 ste-mimics part1


Published on

Published in: Health & Medicine
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • In this lesson I am going to teach you how you can uncover some things if you just dig a little.
  • In this lesson, we are going to perform the third and fourth steps of the six step method.
  • In this lesson, we will learn a few more pathologies which can be identified on a 12-lead ECG. All of these conditions listed can be identified by examining the intervals and morphologies. Lets learn how.
  • RBBB due to difficulty in finding baseline with tachyarrhythmias. Paced rhythms not mentioned, possible nonspecific BBB.
  • RBBB due to difficulty in finding baseline with tachyarrhythmias. Paced rhythms not mentioned, possible nonspecific BBB.
  • When looking for ST-elevation that indicates an MI, we look for changes in contiguous or associated leads. Contiguous leads look at the same area of the heart muscle.
  • Knowing to look for reciprocal changes will assist you in identifying a true myocardial infarction.
  • Left ventricular strain pattern may be identified on some ECGs that have LVH changes. The strain pattern is associated with asymmetrical ST-depression in the left precordial leads, and possibly ST-elevation in the right precordial leads. The ST-segments usually have a curved appearance, and T-wave discordance will be present. The deepest ST-depression will be combined with the tallest R-waves and the highest degree of ST-elevation will be coupled with the deepest S-wave.
  • Here is another example of LVH. This particular 12-lead is formatted slightly differently. The 6 limb leads are on the left and the 6 precordial leads are on the right. Note the obvious strain pattern in the precordial leads. The downward concavity in the left precordial leads is the biggest clue of LV Strain. An ST-Elevation MI with reciprocal changes would have either a straight or convex ST-segment.
  • Here is one of our LVH examples from Lesson 3. We noted that the QRS complexes have been cut short by the monitor to keep them from interfering with nearby leads. This example happens to have changes associated with LV-Strain. Take a look at the T-waves of the precordial leads. Notice the discordance? Every lead but V4 shows T-wave discordance. The transitional leads often have T-wave concordance like V4 on this example. The left precordial leads have obvious downwardly concave ST-depression, and V1 & V2 have slight upwardly concave ST-Elevation. This is a typical LV-Strain pattern, and there is no evidence of MI.
  • Lets take a look at the precordial leads. V1 has the deepest terminal S-Wave which
  • 10 ste-mimics part1

    1. 1. 12-LeadElectrocardiography a comprehensive course -Mi mics STE Pa rt 1 Adam Thompson, EMT-P, A.S.
    2. 2. The 6-Step Method• 1. Rate & Rhythm• 2. Axis Determination• 3. Intervals• 4. Morphology• 5. STE-Mimics• 6. Ischemia, Injury, & Infarct
    3. 3. What is a STEMI?• STEMI = ST-Elevated Myocardial Infarction• Its how we “diagnose” someone with an MI in the field and activate a “STEMI Alert” ST-Segment
    4. 4. STE-Mimics Lessons• STE-Mimics – Any cause of ST-Elevation or AMI-like patterns that is not associated with an actual MI.
    5. 5. Objectives• Learn what the different STE-Mimics are.• Learn how to identify a STE-Mimic.• Learn how to differentiate between a STE- Mimic and a STEMI – (ST-Segment Elevation Myocardial Infarction)
    6. 6. ST-Elevation• The most common cause of ST- elevation is not myocardial infarction.• Less than 50% of STEMI alerts called by paramedics are actually ACS patients
    7. 7. ST-Elevation TP-Segment• ST-Elevation is elevation of the J-Point which causes elevation of the following ST- Segment.• Elevation is defined as anything above the T P isoelectric line.• Find the isoelectric line by locating the TP- Segment.
    8. 8. ST-Elevation• The J-Point is where the QRS complex J-Point and the ST-Segment meet.
    9. 9. Causes of ST-Elevation Listed from most common to least: • Left ventricular hypertrophy (LVH) • Left bundle branch block (LBBB) • Benign early repolarization (BER) • Right bundle branch block (RBBB) • Nonspecific BBB • Ventricular Aneurysm • Pericarditis • Undefined or unknown cause
    10. 10. Causes of ST-Elevation Easier way to remember: E - Electrolytes (hyperkalemia) L - LBBB E - Early repolarization V - Ventricular hypertrophy (LVH) A - Aneurysm T - Treatment (e.i. pericardiocentesis) I - Injury (AMI, contusion) O - Osborne waves (hypothermia) N - Non-occlusive vasospasm
    11. 11. Lead Placement • Poor ECG captures were noted as a common problem. • V3 is most commonly misplaced lead
    12. 12. What are Contiguous Leads?Lead I aVR V1 V4 • Contiguous leads are leads that look at high lateral septal anterior the same area of the heart.Lead II aVL V2 V5 •inferior show up on the 12-lead proximal They high lateral septal low lateral to each other.Lead III aVF V3 V6 inferior inferior anterior low lateral
    13. 13. Reciprocal Changes Site Facing Reciprocal Septal V1, V2 None• Reciprocal changesV4 changes like Anterior V3, are None ST-depression I, aVL, V5, V6 Lateral or T-Wave inversion in II, III, aVF leads opposite to the site of injury. Inferior II, III, aVF I, aVL Posterior V7, V8, V9 V1, V2, V3, V4
    14. 14. Left Ventricular Hypertrophy• The “Strain Pattern” is a repolarization abnormality associated with LVH and may cause ST-Segment changes.• STEMI is more difficult, but still possible to identify in the presence of LVH.
    15. 15. LV Strain Pattern Left Precordial Leads Right Precordial Leads V4, V5, V6 V1, V2, V3Normal Complex
    16. 16. LV Strain• Discordance means opposite. – T-Wave discordance means that the T- Wave is deflected in the opposite direction as the terminal (last) wave of the QRS. – T-Wave discordance is normal in every lead with Left or Right BBBs.
    17. 17. LVH Clues• T wave Discordance (widened QRS/T angle)• Concave ST-Segments with asymmetrical T waves• The height of STE and T waves are directly proportionate to the depth of the S waves. – The taller the R wave the deeper the ST depression.• STE in right precordial leads with depression in left precordial leads due to “strain pattern”.
    18. 18. LV-Strain
    19. 19. LV-Strain
    20. 20. LV-Strain
    21. 21. LV-Strain
    22. 22. The End• More in the next lesson