AEMCA Practice Exam

When might a heart rate decrease be seen in young patients?

1. During physical exertion.

2. When increased vagal tone occurs.

3. During sleep cycles.

4. While experiencing anxiety.

The correct answer is: When increased vagal tone occurs.

A decrease in heart rate, or bradycardia, in young patients can indeed occur when increased vagal tone is present. The vagus nerve, which is part of the parasympathetic nervous system, plays a crucial role in regulating heart rate. When vagal tone increases, it stimulates the heart to slow down, leading to a decrease in heart rate. This phenomenon is particularly common in young patients, especially during moments of relaxation or deeper physiological states like rest or recovery. In scenarios such as sleep cycles, while there may also be a slight decrease in heart rate, the prominent effect of increased vagal tone specifically highlights its influence in lowering the heart rate more distinctly than just general sleep-related changes. Other choices, such as physical exertion and anxiety, typically lead to an increased heart rate as the body responds to heightened activity or stress. Therefore, recognizing the function of vagal tone in controlling heart rate is essential to understanding why this scenario applies to young patients.