Lead II
12-Lead
Interpretation Rules
- Narrow QRS complex, either (1) without a preceding P wave or (2) preceded by an abnormal P wave with a PR interval of < 120 ms (these “retrograde” P wave are usually inverted in leads II, III and aVF).
- Occurs sooner than would be expected for the next sinus impulse.
- Followed by a compensatory pause.
- PJCs that arrive early in the cycle may be conducted aberrantly, most commonly with a RBBB morphology.