Table of contents

1. Introduction to Anatomy & Physiology5h 43m
2. Cell Chemistry & Cell Components12h 36m
3. Energy & Cell Processes10h 6m
4. Tissues & Histology10h 3m
5. Integumentary System2h 20m
6. Bones & Skeletal Tissue2h 16m
7. The Skeletal System2h 35m
8. Joints2h 17m
9. Muscle Tissue2h 33m
10. Muscles1h 11m
11. Nervous Tissue and Nervous System1h 35m
12. The Central Nervous System1h 6m
- Introduction to the Central Nervous System
  18m
- The Cerebrum
  48m
13. The Peripheral Nervous System1h 26m
14. The Autonomic Nervous System1h 38m
15. The Special Senses2h 41m
16. The Endocrine System2h 48m
17. The Blood3h 22m
18. The Heart3h 42m
19. The Blood Vessels3h 35m
20. The Lymphatic System3h 16m
21. The Immune System14h 37m
22. The Respiratory System3h 20m
23. The Digestive System2h 5m
24. Metabolism and Nutrition4h 0m
25. The Urinary System2h 39m
26. Fluid and Electrolyte Balance, Acid Base Balance37m
27. The Reproductive System2h 5m
28. Human Development1h 21m
29. Heredity3h 32m

18. The Heart

Electrocardiogram (ECG)

Anatomy & Physiology

18. The Heart

Electrocardiogram (ECG)

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Multiple Choice

Which electrocardiogram (ECG) finding can be used to measure heart rate?

P wave duration

QRS complex amplitude

R-R interval

T wave inversion

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Verified step by step guidance

Understand the components of an electrocardiogram (ECG). An ECG records the electrical activity of the heart and consists of several waves and intervals, including the P wave, QRS complex, and T wave.

Identify the purpose of each component: The P wave represents atrial depolarization, the QRS complex represents ventricular depolarization, and the T wave represents ventricular repolarization.

Recognize that heart rate is determined by the frequency of heartbeats per minute. To measure heart rate using an ECG, you need to identify a consistent interval between heartbeats.

Focus on the R-R interval: The R-R interval is the time between two consecutive R waves, which are the peaks of the QRS complex. This interval is used to calculate heart rate because it represents one complete cardiac cycle.

Calculate heart rate using the R-R interval: Measure the duration of the R-R interval in seconds and use the formula: Heart Rate = 60 / R-R interval (in seconds). This formula gives the heart rate in beats per minute.