Acute MI Imposters
Specific conditions that occur more frequently in the elderly
A. Myocardial infarction
1. Patient will usually have atypical chest pain or NO pain
2. May present with only dyspnea, acute confusion (delirium), syncope, weakness or nausea and vomiting
Electrocardiographic (ECG) monitoring
A. Electrophysiology and wave forms
1. Origination
2. Production
3. Relationship of cardiac events to wave forms
a. Normal
b. Clinical significance
5. Segments
B. Leads and electrodes
1. Electrode
2. Leads
a. Anatomic positions
b. Correct placement
3. Surfaces of heart and lead systems
a. Inferior
b. Left lateral
c. Anterior/ posterior
4. Artifact
C. Standardization
1. Amplitude
2. Height
3. Rate
a. Duration
b. Wave form
c. Segment
d. Complex
e. Interval
D. Wave form analysis
1. Isoelectric
2. Positive
3. Negative
4. Calculation of ECG heart rate
a. Regular rhythm
i. ECG strip method
ii. "300"/triplicate method
b. Irregular rhythm
i. ECG strip method
ii. "300"/triplicate method
E. Lead systems and heart surfaces
1. ECG rhythm analysis
a. Value
b. Limitations
2. Heart surfaces
a. Inferior
b. Left lateral
c. Precordial
3. Acute signs of ischemia, injury and necrosis
a. Rationale
i. possible early identification of patients with acute myocardial infarction for intervention (thrombolysis PTCA)
ii. the role of out-of-hospital 12-lead ECG is not universally available but is appropriate in most EMS settings with proper medical oversight
b. Advantages/ disadvantages
c. ST segment elevation
i. height, depth and contour
ii. ST (acute changes)
a) anterior wall -- significant ST elevation in V1- V4 may indicate anterior involvement
b) inferior wall -- significant ST elevation in II, III and aVF may indicate inferior involvement
iii. ST segment depression in eight or more leads
iv. ST segment elevation in aVR and V1
d. Q waves
i. depth, duration and significance
a) greater than 5 mm, greater than .04 seconds
b) may indicate necrosis
c) may indicate extensive transient ischemia
Abnormal presentations
The most common things that throw off a 12-lead interpretation
Content Creator: Josh Renolds
CAPCE Course Number: 20-EMTP-F3-7214
Total CE Hours: 1.5
Level: Advanced
EMT-CE uses the NEMSES guidelines as the foundation for every course outline.
