Learning Objectives

• Explain why dysrhythmias are divided into three classes
• Explain each of the three common mechanisms of abnormal sites of impulse initiation
• Compare and contrast sinus tachycardia, sinus bradycardia, sinus arrhythmia and sinus arrest
• Compare and contrast the different types of conduction blocks
• Compare and contrast junctional and ventricular escape rhythms
• Explain how abnormal sites of impulse initiation may produce atrial flutter, atrial fibrillation, ventricular tachycardia, ventricular fibrillation, and premature complexes (atrial or ventricular)
• Define accessory pathways and pre-excitation, using WPW syndrome as an example
• Understand how and why the ECG changes in each dysrhythmia

Abnormal Rates of Sinus Rhythm

• what are the parameters of NSR?
• Sinus Bradycardia
• Sinus Tachycardia
• Sick Sinus Syndrome
• Sinus Arrhythmia
• Sinus Arrest

Conduction System Disturbances

• what are escape rhythms?
• how does a junctional escape rhythm present on an ECG?