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ECG Interpretation

Systematic step-by-step analysis. Complete each section then generate a structured summary.

1 Heart Rate

Choose your calculation method:

2 Rhythm

3 PR Interval

4 QRS Complex

5 Axis

6 ST Segment & T Waves

ECG Interpretation Summary

This is a decision-support summary only. Confirm all findings with clinical context and senior clinician review where appropriate.

Normal Intervals

PR interval120–200 ms

QRS duration< 120 ms

QT (heart rate dependent)Varies

QTc ♂< 440 ms

QTc ♀< 450 ms

ST elevation (limb)< 1 mm

Rate Interpretation

<60 bpm — Bradycardia

60–100 bpm — Normal

101–150 bpm — Tachycardia

150–250 bpm — Rapid tachycardia

>250 bpm — Flutter / VF threshold

STEMI Criteria

≥1 mm ST elevation in ≥2 contiguous limb leads

≥2 mm ST elevation in ≥2 contiguous precordial leads (men)

≥1.5 mm in V2-V3 (women)

New LBBB + ischaemic symptoms = treat as STEMI equivalent

Territory — Leads:

Inferior: II, III, aVF

Anterior: V1–V4

Lateral: I, aVL, V5–V6

Posterior: tall R + ST dep in V1–V2

RV: ST elevation in V4R

Disclaimer: This tool is a systematic guide only. ECG interpretation requires clinical context. Always refer to senior clinician or medical control for STEMI activation decisions.