What condition is characterized by a heartbeat that is too rapid with a regular rhythm?

Sinus tachycardia is characterized by a heartbeat that is faster than normal while maintaining a regular rhythm. In this condition, the heart rate exceeds 100 beats per minute and arises from the sinoatrial node, which is the natural pacemaker of the heart. This elevated heart rate can occur in response to various factors such as exercise, anxiety, fever, or other physiological stressors.

The regularity of the rhythm in sinus tachycardia is a key distinguishing factor, as the rhythm remains consistent without the irregularities seen in other arrhythmias, such as atrial fibrillation. Consequently, sinus tachycardia is often a response to increased demand for oxygenated blood in the body rather than a pathological issue by itself.

In contrast, bradycardia refers to a slow heartbeat, atrial fibrillation involves an irregular rhythm typically associated with a rapid and disorganized electrical activity in the atria, and premature ventricular contractions are early heartbeats originating from the ventricles, which can disrupt the normal rhythm but do not maintain a consistent rate.