- PR interval > 200ms (five small squares)
- ‘Marked’ first degree block if PR interval > 300ms
First degree heart block (PR interval > 200 ms)
Marked first degree heart block (PR interval > 300 ms, P waves are buried in the preceding T wave)
- Does not cause haemodynamic disturbance
- No specific treatment is required
- ECG BASICS — Waves, Intervals, Segments and Clinical Interpretation
- ECG CLINICAL CASES — Your favourite ECG’s placed in clinical context with a challenging Q&A approach
- ECG and Cardiology Eponymous Syndromes — Cheats guide to eponymous emancipation
- ECG Exam Template — a framework for the FACEM part 2 exam.
- ECG Reference Sites on the WEB — the best of the rest
- Hampton, JR. The ECG in Practice (5th edition), Churchill Livingstone 2008.
- Wagner, GS. Marriott’s Practical Electrocardiography (11th edition), Lippincott Williams & Wilkins 2007.