What can be a consequence of severe bradycardia?

Severe bradycardia, characterized by a heart rate significantly lower than normal (typically below 60 beats per minute), can lead to insufficient blood flow to the brain. This reduced cerebral perfusion can result in syncope or fainting, as the brain is not receiving the oxygen and nutrients it requires to function effectively. When the heart beats infrequently, less blood is pumped throughout the body, potentially compromising the delivery of oxygen-rich blood to vital organs, including the brain, leading to these episodes of loss of consciousness.

While decreased cardiac output and blood pressure can occur during severe bradycardia, the very specific and notable symptom among the options provided is syncope, which is a direct consequence of inadequate cerebral blood flow. Increased cardiac output, on the other hand, would not occur in a state of bradycardia. Similarly, a decreased respiratory rate is not a primary consequence of bradycardia, though it may occur under certain circumstances or as part of a broader clinical picture.