Tachycardia is defined as a cardiac rate that is increased to >100 beats/minute (bpm).

Tachyarrhythmia is used to describe tachycardia in the presence of cardiac rhythm abnormality.

Divided into supraventricular and ventricular tachycardia.

Signs and symptoms related to rapid heart rate are altered sensorium, angina, shortness of breath, myocardial infarction, hypotension and other signs of shock (eg cold clammy skin, low urine output), heart failure or pulmonary congestion.