1. Exercise Related to ECG and Medications
chapter 24
Exercise Related to ECG and Medications

2. Heart Chambers and Valves
Reprinted from J.E. Donnelly, 1990, Living anatomy, 2nd ed. (Champaign, IL: Human Kinetics), 199. Reprinted by permission of Joeseph Donnelly.

3. Coronary Blood Vessels
Reprinted from J.E. Donnelly, 1990, Living anatomy, 2nd ed. (Champaign, IL: Human Kinetics), 199. Reprinted by permission of Joeseph Donnelly.

4. Oxygen Use by the Heart The myocardium relies on ATP for contraction.
In the heart, 40% of the muscle cells are mitochondria.
Even at rest, the heart muscle extracts 75% of the O2 delivered to it.

5. Electrophysiology of the Heart
At rest, the insides of heart muscle cells are negatively charged.
When depolarized, the insides of the cells become positively charged.
If a wave of depolarization travels toward a positive electrode on the ECG, an upward deflection occurs.

6. Steps in an ECG Cycle

7. Electrical Conduction System of the Heart

8. Parts of the Electrical System
Sinoatrial Node:
Atrioventricular Node:

9. HIS-Purkinje System His Bundle (start of the system)
Right Bundle Branch
Left Bundle Branch
Purkinje fibers
Rate:

10. Electrocardiogram
Electrocardiogram (ECG)

12. ECG Complex Showing Time and Voltage Scales
Adapted from M.J. Goldman, 1982, Principles of clinical electrocardiography, 11th ed. (Los Altos, CA: Appleton & Lange), with permission of The McGraw-Hill Companies.

13. R T P T
Knowledge of electrocardiography (ECG) is essential in clinical exercise physiology.
The 12-lead ECG is a vital component of the evaluation of heart function during the exercise test. P Q S
P-R
Q-T
Arial depolarization
Ventricular depolarization

14. ECG Wave Forms (continued)
P wave:
QRS complex:
T wave:

15. RATE

16. Normal Sinus Rhythm .

17. Sinus Bradycardia

18. Sinus Tachycardia

19. First-Degree AV Block

20. Second-Degree AV Block Type I (Mobitz Type I, or Wenckebach)

21. Second-Degree AV Block Type II (Mobitz Type II)

22. Third-Degree AV Block

23. Premature Atrial Contractions

24. Atrial Flutter

25. Atrial Fibrillation

26. Premature Junctional Contractions (PJCs)

27. Premature Ventricular Contractions (PVCs)

28. Ventricular Tachycardia

29. Ventricular Fibrillation
When there are no discernible P waves or QRS complexes, the heart contracts in a disorganized, quivering manner.

30. Myocardial Ischemia

31. Myocardial Infarction
Reprinted, by permission, from E. Stein, 1992, Rapid analysis of electrocardiograms, 2nd ed. (Philadelphia, PA: Lea & Febiger), 150.

32. Cardiovascular Medications
Beta-blockers
Nitrates
Calcium channel blockers
Antiarrhythmic medications
Digitalis
(continued)

33. Cardiovascular Medications (continued)
Antihypertensives
Lipid-lowering agents
Anticoagulants
Nicotine patches and gums
Bronchodilators