ECG AND RHYTHM INTERPRETATION EXAM PRACTICE CASE STUDIES II RHYTHM STRIPS AND ECGS CONTRIBUTED BY FRANK YANOWITZ, MD ECG LEARNING CENTER

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ECG AND RHYTHM INTERPRETATION EXAM PRACTICE
CASE STUDIES II
RHYTHM STRIPS AND ECGS CONTRIBUTED BY FRANK YANOWITZ, MD ECG
LEARNING CENTER




Gannett Education ©

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Quick Review: Analysis Process


• Name the steps in the analysis of an ECG

1. Rate

2. Rhythm

3. Blocks

4. Axis

5. Hypertrophy

6. Myocardial injury

7. Special issues
• What is the heart rate & rhythm?
− 300, 150, 100, 75
− Rhythm regular
− Normal Sinus




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Additional Rhythm Analysis


• What should you always ask yourself in assessing a heart rhythm?

– Is the P wave followed by QRS?

– What is the morphology of the P wave?

– What is the relationship of the P to QRS?

– Is the rhythm regular/irregular/irregularly irregular?

– What is the QRS width?

• <120ms (0.12 sec, 3 sm boxes ) - supraventricular source
= narrow QRS

• >120 ms (0.12 sec, 3 sm boxes) - ventricular source (or BBB) = wide QRS




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Name that Rhythm


• What is wrong with this rhythm strip?




PR 0.28 PR 0.28 PR 0.28

– Normal PR interval 0.12-0.20 sec (3-5 small squares)

– Prolonged PR interval (>5 small squares)

– Slow conduction through the AVN
• First degree AV block




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