GROSS ANATOMY

Detailed explanation-1: -While lying on your back, take a deep breath and act like you’re exhaling but with your nose and mouth closed for 10 to 30 seconds. It should feel like trying to breathe air out into a blocked straw.

Detailed explanation-2: -It is well accepted that the vagus nerve slows heart rate (HR), atrioventricular conduction and decreases atrial contraction, with vagus nerve stimulation (VNS) resulting in anti-arrhythmic effects and acting in a cardioprotective manner (Brack et al., 2013).

Detailed explanation-3: -The higher the vagus nerve activity is, the slower the heart rate is, the greater the increase in the parasympathetic component of heart rate variability is, and the better the outcome is. In HF, heart rate is less regulated by parasympathetic activation.

Detailed explanation-4: -The motor vagus nerve constitutes the main peripheral neural structure of the parasympathetic autonomic nervous system (ANS).

Detailed explanation-5: -VNS can be used effectively and rapidly to decrease heart rate, in acute settings, when connected to an external pacing system.