What condition is defined by a heart rate exceeding 140 beats per minute?

A heart rate exceeding 140 beats per minute is categorized as tachycardia. Tachycardia is a clinical term used to describe a condition where the heart beats faster than the normal resting heart rate, which typically ranges from 60 to 100 beats per minute in adults. This elevated heart rate can occur due to various factors such as physical activity, stress, anxiety, fever, or underlying medical conditions. Understanding tachycardia is crucial in the context of ACLS, as it can lead to decreased cardiac output and may require immediate intervention depending on the patient's stability and the underlying cause.

The other conditions listed—bradycardia, normal sinus tachycardia, and aortic regurgitation—are different and relate to various heart rate and structural heart issues. Bradycardia refers to a slower-than-normal heart rate (below 60 beats per minute), normal sinus tachycardia refers specifically to a faster heart rate that is still acceptable in certain circumstances (but typically does not exceed 100 to 120 beats per minute), and aortic regurgitation is a heart valve condition that affects the blood flow rather than the heart rate itself. Thus, understanding the distinguishing features of tachycardia is essential in clinical scenarios