Certified Cardiographic Technician (CCT) Exam 2025 – 400 Free Practice Questions to Pass the Exam

Sinus bradycardia is characterized by a slower than normal heart rate, usually defined as fewer than 60 beats per minute. One of the primary physiological conditions that can lead to this state is increased vagal tone or hypothermia.

Increased vagal tone refers to enhanced activity of the vagus nerve, which is part of the parasympathetic nervous system. This increased activity can lower the heart rate because it promotes a state of relaxation and reduces the signals that stimulate the heart to beat faster. Conditions that naturally elevate vagal tone include rest and relaxation, but can also be seen during certain physiological states, such as sleep or in response to specific stimuli like deep breathing.

Hypothermia also contributes to sinus bradycardia as the body’s metabolic processes slow down and the autonomic nervous system responds by decreasing heart rate to conserve energy. The combination of these effects leads to a more pronounced reduction in heart rate, manifesting as bradycardia.

In contrast, exercise and increased heart rate would naturally elevate the heart rate instead of leading to bradycardia. Decreased vagal tone would result in an increased heart rate, and high fever typically leads to tachycardia, which is the opposite of brady