1. Putting It All Together22
Putting It All Together
Fast & Easy ECGs, 2nd E – A Self-Paced Learning Program

2. Analyzing ECGs
The nine-step process can be used to analyze ECGs

3. Heart Rate Are either slow, normal, or fast
Some dysrhythmias may produce more than one heart rate or even all three

4. Heart Rate

5. Regularity Dysrhythmias will either be regular or irregular
Irregularity can be furthered characterize into the following groups:
occasional or very
slight
sudden acceleration or slowing
patterned
total
variable conduction ratio irregularity

6. Regularity

7. P Waves
Depending on where each dysrhythmia originates, P waves are either present or not present
If P waves are present, they are either normal or abnormal
Sometimes there are more P waves than QRS complexes
Also, with certain dysrhythmias, flutter or fibrillatory waveforms are present instead of P waves

8. P Waves

9. QRS Complexes
Depending the lead viewed, QRS complexes should appear upright and narrow
Abnormal QRS complexes
Can vary from being only slightly abnormal to being extremely wide, notched, or slurred
Extremely abnormal configurations are referred to as bizarre-looking because they deviate so far from normal
Abnormal QRS complexes can occur when the pacemaker is initiated from above the ventricles as well as when it is initiated from within the ventricles

10. QRS Complexes

11. PR Intervals
Normal PR intervals are within 0.12 to 0.20 seconds and constant in duration
Abnormal PR intervals are those that are shorter than 0.12 seconds, are longer than 0.20 seconds, are absent, or vary in duration

12. PR Intervals

13. ST Segments ST segments are either present or not present
If they are present, they are either normal or abnormal
Abnormal ST segments are categorized:
Elevated
Depressed
Indistinguishable (in certain dysrhythmias)

14. ST Segments
ST Segments

15. T Waves T waves are either present or not present
If they are present, they are either normal or abnormal
Abnormal T waves include tall or peaked, heavily notched or pointed, inverted, flat, with bumps and those that take an opposite direction to the QRS complex

16. T Waves
T Waves

17. QT Intervals
Unless there are no Q waves and/or T waves, the QT interval is present
QT intervals are normal or abnormal
Abnormal QT intervals are:
Prolonged
Shortened
Not measureable

18. QT Intervals

19. U Waves
U waves are either present or not present

20. U Waves

21. Questions to Ask Is the rate of this dysrhythmia slow, normal or fast?
Is this rhythm regular or irregular? If it is irregular, what type of irregularity is it?
Are there P waves? What do they look like? Is each followed by a QRS complex?
Are the QRS complexes present? If so, what do they look like?
Are the PR intervals present? If so, what is their duration and is it constant?
Are the ST segments present? If so, are they normal or abnormal?
Are the T waves present? If so, are they normal or abnormal?
Are the QT intervals measurable? If so, are they normal or abnormal?
Are U waves present?

22. Practice Makes Perfect
Analyze this ECG
Answer:
Rate: 125 BPM; Rhythm: regularly irregular; P waves: normal in underlying rhythm, absent in early beats; QRS complexes: QS complexes in underlying, wide and bizarre-looking in early beats; PR intervals: 0.18 seconds and constant in underlying rhythm, absent in early beats; ST segments: normal in underlying rhythm, absent in early beats; T waves: normal in underlying rhythm, deflect opposite direction to QRS complexes in early beats; QT interval: shortened 0.34 seconds in duration; U waves: none; Diagnosis: Sinus tachycardia with quadrigeminal PVCs
6 second strip I

23. Practice Makes Perfect
Analyze this ECG
6 second strip
Answer:
Rate: 71 BPM; Rhythm: regular; P waves: unable to identify; QRS complexes: wide and bizarre-looking QS complexes; PR intervals: absent; ST segments: normal; T waves: deflect opposite direction to QRS complexes; QT interval: lengthened 0.56 seconds in duration; U waves: none; Diagnosis: Ventricular pacemaker I

24. Practice Makes Perfect
Analyze this ECG
6 second strip
Answer:
Rate: 110 BPM; Rhythm: totally irregular; P waves: unable to identify; QRS complexes: normal RS complexes; PR intervals: absent; ST segments: normal; T waves: normal where seen; QT interval: normal 0.36 seconds in duration; U waves: none; Diagnosis: Atrial fibrillation with rapid ventricular response I

25. Practice Makes Perfect
Analyze this ECG
Answer:
Rate: 70 BPM; Rhythm: regularly irregular; P waves: normal in underlying rhythm, absent in early beats; QRS complexes: pathological Q waves in underlying, wide and bizarre-looking in early beats; PR intervals: 0.18 seconds and constant in underlying rhythm, absent in early beats; ST segments: elevated in underlying rhythm, absent in early beats; T waves: inverted in underlying rhythm, deflect opposite direction to QRS complexes in early beats; QT interval: normal 0.40 seconds in duration; U waves: none; Diagnosis: Sinus rhythm with presumed quadrigeminal PVCs (as the tracing is limited to six seconds)
6 second strip I

26. Practice Makes Perfect
Analyze this ECG
6 second strip
Answer:
Rate: 115 BPM; Rhythm: regular; P waves: normal; QRS complexes: narrow RS complexes; PR intervals: 0.12 seconds and constant; ST segments: normal; T waves: normal; QT interval: shortened 0.34 seconds in duration; U waves: none; Diagnosis: Sinus tachycardia I

27. Practice Makes Perfect
Analyze this ECG
6 second strip
Answer:
Rate: 94 BPM; Rhythm: regular; P waves: absent; QRS complexes: wide and bizarre-looking; PR intervals: absent; ST segments: indistinguishable; T waves: deflect opposite direction to QRS complexes; QT interval: lengthened 0.60 seconds in duration; U waves: none; Diagnosis: Ventricular tachycardia I

28. Practice Makes Perfect
Analyze this ECG
6 second strip
Answer:
Rate: 44 BPM; Rhythm: regular; P waves: normal; QRS complexes: narrow, slurred RS complexes; PR intervals: 0.28 seconds and constant; ST segments: normal; T waves: normal; QT interval: lengthened 0.42 seconds in duration; U waves: none; Diagnosis: Sinus bradycardia with 1st degree AV block I

29. Practice Makes Perfect
Analyze this ECG
Answer:
Rate: 77 BPM; Rhythm: regular; P waves: normal; QRS complexes: wide; PR intervals: 0.20 seconds and constant; Diagnosis: Sinus rhythm with left bundle block I

30. Practice Makes Perfect
Analyze this ECG
Answer:
Rate: 116 BPM; Rhythm: totally irregular; P waves: indiscernible; QRS complexes: QS complexes in many leads; PR intervals: absent; ST segments: elevated in leads V1 through V5; T waves: elevated in leads V2 and V3; Diagnosis: Atrial fibrillation with extreme axis deviation, anteroseptal infarct, possible lateral injury pattern, artifact in some leads I

31. Practice Makes Perfect
Analyze this ECG
Answer:
Rate: 84 BPM; Rhythm: regular; P waves: wide; QRS complexes: wide, slurred rsR’S’ complexes; PR intervals: 0.12 seconds and constant; ST segments: normal; T waves: inverted in leads V1 to V3; QT interval: normal 0.36 seconds in duration; U waves: none; Diagnosis: Sinus rhythm with left atrial enlargement, right bundle branch block, possible inferior infarction – age undetermined I

32. Summary Use the nine-step process to analyze the ECG
Determine the rate
Determine rhythm
Determine the presence and appearance of the P waves
Determine the presence, appearance and duration of QRS complexes
Determine the presence and duration of PR intervals
Determine the presence and appearance of ST segments
Determine the presence and appearance of T waves
Determine the duration of the QT intervals
Determine the presence of U waves
Compare findings against the characteristics of the various dysrhythmias and conditions