which term describes an abnormally rapid resting heartbeat?
Equally 120 may be tachycardia for most of us but it is a normal rate for babies. Arrhythmia is a term used to describe any abnormal heart rate. A tachyarrhythmia is an abnormally fast heart rate that typically is not regular or predictable. Normal resting heart rate is said to be between 60 and 100 beats per minute.