ECGs for Nurses
Chapter One
The Conduction System
in the Heart
INTRODUCTION
The conduction system in the heart is an intrinsic system whereby
the cardiac muscle is automatically stimulated to contract, without
the need for external stimulation (Waugh & Grant, 2007). It
comprises specialised cardiac cells, which initiate and conduct
impulses, providing a stimulus for myocardial contraction. It is
controlled by the autonomic nervous system; the sympathetic
nerves increase heart rate, contractility, automaticity and atrioventricular
(AV) conduction, while the parasympathetic nerves
have an opposite effect.
Irregularities in the conduction system can cause cardiac arrhythmias
and an abnormal electrocardiogram (ECG). An understanding
of the conduction system and how it relates to myocardial
contraction and the ECG is essential for ECG interpretation.
The aim of this chapter is to understand the conduction system
in the heart.
LEARNING OUTCOMES
At the end of the chapter the reader will be able to:
Discuss the basic principles of cardiac electrophysiology ... read full excerpt from ECGs for Nurses (Essential Clinical Skills for Nurses #14) ebook
