Diagnosis
No formal diagnostic criteria exist. A diagnosis of Inappropriate sinus tachycardia is primarily one of exclusion and the following may be observed:
- Exclusion of all other causes of sinus tachycardia
- Common forms of supraventricular tachycardia (SVT) must be excluded
- Normal P wave morphology
- A resting sinus tachycardia is usually (but not always) present
- Nocturnal dip in heart rate
- Inappropriate heart rate response on exertion
- Mean heart rate in 24hrs >95bpm
- Symptoms are documented to be due to tachycardia
- Hypotension is occasionally observed
- Syncope (fainting) is occasionally reported
Read more about this topic: Inappropriate Sinus Tachycardia