Final answer:
Idioventricular rhythm is the ventricular dysrhythmia associated with a heart rate less than 20 bpm, which is a severe form of bradyarrhythmia that may require medical intervention, such as a pacemaker, if symptomatic.
Step-by-step explanation:
The ventricular dysrhythmia that has a heart rate less than 20 beats per minute (bpm) is known as idioventricular rhythm or agonal rhythm. This is a type of bradyarrhythmia and is characterized by the absence of the SA node firing or a complete heart block, where the Purkinje fibers act as the pacemaker of the heart with an inherent rate of 15-20 bpm. This condition is extremely slow and can be life-threatening as the heart is unable to maintain adequate blood flow to vital tissues, which can result in decreased function across various systems, unconsciousness, or in severe cases, death.
Treatment of bradycardia or idioventricular rhythm depends on the underlying cause and severity of the symptoms. Conditions such as metabolic disorders, endocrine system pathologies, electrolyte imbalances, and other factors could induce bradycardia. In cases where the patient exhibits symptoms like weakness, fatigue, dizziness, or chest pain, the heart may not be providing sufficient oxygenated blood to the tissues, making medical intervention necessary. This may include pacemaker insertion if there is a persistent low heart rate due to intrinsic heart conduction system failure.