1. Electrocardiogram Primer (EKG-ECG)
Holdorf PhD, MPA, RDMS, RVT, LRT(AS)

2. Normal complex P wave-atrial systole
QRS complex – ventricular systole (depolarization)
T wave – Ventricular diastole (repolarization)

4. Hint: 1 small box = 0.04 seconds 1 big box = 0.2 seconds
5 big boxes = 1 second

5. Normal values:
R-R interval: between 3 to 5 big boxes ( beats/minute
QRS complex: less than 3 little boxes (less than .12 seconds
PR interval: Less than 1 big box (less than 0.2 seconds)
The ECG has which of the following rhythms?
Normal sinus rhythm (via the SA node)

6. Method of analysis Find the P waves (they’re the big ones)
Method of analysis Find the P waves (they’re the big ones) Assess at the QRS duration (< little boxes) Assess at R-R interval: between 3 and 5 big boxes Look for P preceding each R wave Check the PR interval (less than I big box)

7. ECG: Common abnormalities
Normal sinus rhythm (R-R interval between 3 and 5 big boxes
BPM
P-wave preceding each QRS
PR interval and QRS complex within normal limits

8. SINUS BRADYCARDIA (more than 5 big boxes Heart rate less than 60 BPM Otherwise all other findings of normal sinus rhythm

9. SINUS TACHYCARDIA Less than 3 big boxes Heart rate greater than 100 BPM Otherwise all other findings of normal sinus rhythm

10. If the cardiac electrical impulse is in the bundle branches, where are you on the ECG tracing? The Purkinje fibers The bundle of His?
Answer for all
PR interval

12. ARRHYTHMIAS OVERVIEW P waves PR Interval QRS Duration
Present or absent
Relationship to QRS
PR Interval
Normal < 0.20 sec.
QRS Duration
Normal <0.12 sec.

13. Sinus arrhythmia Irregular rhythm related to respiration (increase rate with inspiration; decrease rate with expiration

14. In sinus arrhythmia, the heart rate varies with the phase of respiration.  The heart rate typically increases during inspiration and decreases during expiration.  Therefore, as observed, the R-R interval is longer during expiration.  These changes are mediated through vagal reflexes.  Sinus arrhythmia is more common in young healthy athletes.

15. Atrial fibrillation
Rapid discharge of multiple foci in the atria, no discrete P waves, irregularly irregular rhythm.

17. Atrial flutter Rapid discharge of an ectopic focus for atrial depolarization. Only occasional stimulus will penetrate AV node. Saw-tooth pattern.

18. Ventricular Fibrillation Chaotic rhythm in which there are multiple areas exhibiting varying degrees of depolarization and repolarization. Absence of R-waves

19. Premature Beats Atrial (PAC) Electrical impulse originating in the atria outside of the SA node. Produces an abnormal P wave earlier than expected.

20. Ventricular (PVC-premature ventricular contractions) Ectopic ventricular focus (anatomic source) produces an abnormal ventricular complex (usually larger and wider than normal complex). A PVC occurring every other beast is called bigeminy A PVC occurring every 3rd beat is trigeminy

21. Ventricular tachycardia Three or more beast of ventricular origin (PVC) occurring in succession.

22. Bundle Branch Block Right BBB= delay in depolarization of the right ventricle: QRS > 0.12 sec.

23. Left BBB Delay in depolarization of the left ventricle V5 or V6 QRS > 0.12 sec.

24. Heart Block 1st degree AV Block. PR interval >0. 20 sec
Heart Block 1st degree AV Block PR interval >0.20 sec. (more than I big box) and of the same duration in every cycle. R-R interval is normal.

25. 2nd degree AV Block PR interval >0. 20 sec
2nd degree AV Block PR interval >0.20 sec. and gets progressively longer until a QRS is dropped. In other words, the P moves further away from the QRS.

26. 3rd degree AV block
Complete absence of conduction between the atria and ventricles (also known as complete heart block (CHB).
P-R interval gets progressively shorter.
In other words, the P marches straight into the QRS complex.

28. Pacemakers A high voltage, short duration pacing spike seen before each ventricular conduction pattern.

29. Exercise Stress Testing
Indications
To aid in the diagnosis of chest pain
To determine the severity and prognosis of CAD
To guide post MI rehab
To evaluate cardiac arrhythmias
To screen high risk professionals or asymptomatic patients
Interpretation
Morphology, degree and duration of ST-Segment depression (Mechanical / pressure)
ST = segment elevation
Duration of exercise
Exercise-induced hypotension or arrhythmias