What condition does tachycardia describe?

Tachycardia refers specifically to an abnormally fast heart rate, typically defined as a resting heart rate that exceeds 100 beats per minute in adults. This condition can occur due to various reasons, such as exercise, anxiety, fever, or heart-related issues, and it is important to monitor because it can indicate underlying health problems or stress on the heart.

The other options describe different heart-related conditions. A slow heart rate is referred to as bradycardia. A normal heart rate for adults usually ranges from 60 to 100 beats per minute, which is not tachycardia. An irregular heart rhythm, known as arrhythmia, involves abnormal heartbeats but does not define the speed of the heart rate itself. Understanding these distinctions is crucial for recognizing and responding to various cardiovascular conditions.