Human Anatomy and Physiology

Chapter 17 The Cardiovascular System I: The Heart

 
Overview of the Heart

Learning Outcomes

1. Describe the position of the heart in the thoracic cavity.
2. Describe the basic surface anatomy of the chambers of the heart.
3. Explain how the heart functions as a double pump and why this is significant.

1. Describe the histology of cardiac muscle tissue, and differentiate it from that of skeletal muscle.
2. Describe the phases of the cardiac muscle cell action potential, including the ion movements that occur in each phase, and explain the importance of the plateau phase.
3. Contrast the way action potentials are generated in cardiac pacemaker cells, cardiac contractile cells, and skeletal muscle cells.
4. Describe the parts of the cardiac conduction system, and explain how the system functions.
5. Identify the waveforms in a normal electrocardiogram (ECG), and relate the ECG waveforms to electrical activity in the heart..

1. Describe the phases of the cardiac cycle.
2. Relate the opening and closing of specific heart valves in each phase of the cardiac cycle to pressure changes in the heart chambers.
3. Relate the heart sounds and ECG waveforms to the normal mechanical events of the cardiac cycle.
4. Compare and contrast pressure and volume changes of the left and right ventricles and the aorta during one cardiac cycle.

1. Define and calculate cardiac output, given stroke volume, heart rate, and end-diastolic and end-systolic volumes.
2. Describe the factors that influence preload, afterload, and contractility, and explain how they affect cardiac output.
3. Explain the significance of the Frank-Starling law for the heart.
4. Discuss the influence of positive and negative inotropic and chronotropic agents on stroke volume and heart rate, respectively.
5. Predict how changes in heart rate and/or stroke volume will affect cardiac output.