Final answer:
Ventricular dysrhythmia with a heart rate less than 20 beats per minute is a severe bradycardia, indicating potential failure in the heart's electrical conduction system, specifically the Purkinje fibers.
Step-by-step explanation:
The ventricular dysrhythmia with a heart rate less than 20 beats per minute is a severe form of bradycardia. Bradycardia refers to a slower than normal heart rate, defined as fewer than 60 beats per minute in a resting adult. When the heart rate falls significantly below this threshold, such as less than 20 beats per minute, it usually suggests a problem with the electrical conduction system of the heart. In the conduction system, the Purkinje fibers would typically fire at a rate of 15-20 impulses per minute if higher pacemaker activity fails. However, rates this low could lead to inadequate blood flow to vital tissues and, if untreated, may result in decreased systemic function, unconsciousness, or worse. Treatment of profound bradycardia requires immediate medical attention, often including a pacemaker to maintain an adequate heart rate.