RCIS ECG Study Guide
The ECG essentials the RCIS exam tests — waves, intervals, and the arrhythmias you must recognise.
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Waves and intervals
- P wave — atrial depolarization.
- QRS — ventricular depolarization (normal <0.12 s).
- T wave — ventricular repolarization.
- PR interval — 0.12–0.20 s.
Key arrhythmias to recognise
- Atrial fibrillation — irregularly irregular, no P waves.
- Atrial flutter — sawtooth flutter waves.
- VT — regular wide-complex tachycardia.
- VFib — chaotic, no pulse → defibrillate.
- Complete heart block — P and QRS dissociated.
Frequently asked questions
What does the QRS complex represent?
Ventricular depolarization; a normal QRS is under 0.12 seconds.
How is ventricular fibrillation treated?
Immediate defibrillation with CPR — it is a pulseless emergency.