What are the two conditions known as when the heart's lower chambers beat too quickly or quiver?

The situation described in the question refers to two specific cardiac conditions where the heart's lower chambers, or ventricles, exhibit abnormal rhythms. The correct answer identifies these as pulseless ventricular tachycardia and ventricular fibrillation.

Pulseless ventricular tachycardia (VT) occurs when the ventricles beat very quickly, often at a rate that does not allow them to fill properly with blood before contracting. This can lead to a decrease in cardiac output and result in a lack of pulse and consciousness. It's a critical condition requiring immediate intervention.

Ventricular fibrillation (VF), on the other hand, is characterized by rapid, erratic electrical impulses in the heart's ventricles, causing them to quiver instead of contracting effectively. This condition also prevents the heart from pumping blood, leading to a lack of pulse and necessitating urgent medical attention.

Both of these conditions are life-threatening and require prompt action, such as CPR and defibrillation, to restore a normal heart rhythm and prevent cardiac arrest. Understanding these conditions is vital for anyone training in lifeguard certification, as recognizing and responding to cardiac emergencies is a key component of the training.