Cardiology Teaching Package
A Beginners Guide to Normal Heart Function, Sinus Rhythm & Common Cardiac Arrhythmias
Sinus Tachycardia
During exercise, it is common for a person's heart rate to go above 100bpm. This is known as Tachycardia and, if the rhythm is sinus, it is known as Sinus Tachycardia.
Sinus tachycardia is not a different rhythm, it is simply sinus rhythm going faster than 100 bpm.
Image: Sinus Tachycardia
- R-R intervals constant and regular
- One P-wave per QRS complex
- All waveforms present
- Rate is > 100bpm, but not usually > 130bpm at rest
- Occurs normally in exercise / stress. Patient is usually asymptomatic.
- Other causes may be hypovolaemia / underlying medical problems
The passage of conduction through the heart in both sinus tachycardia and sinus bradycardia is exactly the same as in sinus rhythm.
Both rhythms are naturally occurring but can also be brought on by an overdose of both legal and illegal drugs.
