What heart rate defines sinus bradycardia?

Sinus bradycardia is defined as a heart rate that is less than 60 beats per minute. This condition occurs when the sinus node, which is responsible for initiating the electrical impulses that trigger heartbeats, generates impulses at a slower rate than normal. In a healthy adult, the typical resting heart rate ranges from 60 to 100 beats per minute. Therefore, when the heart rate drops below 60, it qualifies as bradycardia.

It's important to recognize that the threshold of 60 beats per minute has been established as the standard clinical definition for diagnosing sinus bradycardia because it signifies a significant deviation from normal heart function that can potentially lead to inadequate blood flow and result in symptoms such as fatigue, dizziness, or even syncope if the heart's output is insufficient to meet the body's demands.