2.0 The heart physiology

Heart physiology is the understanding of how the electrical conduction pathways of the heart lead to the contraction of the heart muscle, and how these are regulated  to maintain the volume of blood pumped out of the heart every minute (known as cardiac output)

Before you start studying cardiac physiology, it would be useful to familiarise yourself with the topics of: ion channels, membrane potentials (resting potential, depolarization), nerve cell action potential and skeletal muscle contraction.

Learning outcomes:

After studying the topic of cardiac physiology you should be able to:

•  describe the characteristic structure of cardiac muscle cells
• describe the heart’s electrical wiring and various types of pacemaker cell location and rhythm
• explain how the pacemaker cells work
• explain cardiac  contraction  and the of calcium  to  provide  a  sustained depolarization – and the physiological consequences of this
• describe the nervous system regulation of the cardiac contraction
• simply describe an ECG, what a normal ECG says and what one can read from it
• explain the terms diastole, systole, end diastolic volume, systolic volume, stroke volume, cardiac output and apply these terms together