To read an ECG report effectively, follow a systematic step-by-step approach focusing on key components of the ECG trace:

Step-by-Step Guide to Reading an ECG Report

1. Confirm Patient and ECG Details

• Verify patient name, date of birth, and hospital number.
• Check the date and time of the ECG recording and ensure calibration is correct.
• Understand the clinical context or reason for the ECG (e.g., chest pain, breathlessness)

2. Assess Heart Rate

• Calculate heart rate by counting the number of QRS complexes in a 6-second strip and multiplying by 10, or count QRS complexes in one lead and multiply by 6 for a 10-second strip.
• Normal heart rate is 60–100 beats per minute. Rates above 100 indicate tachycardia, below 60 indicate bradycardia

3. Evaluate Heart Rhythm

• Determine if the rhythm is regular or irregular by measuring intervals between R waves (R-R intervals).
• Check for presence and consistency of P waves before each QRS complex, indicating sinus rhythm

4. Analyze Cardiac Axis

• Assess the overall direction of electrical activity in the heart (normal axis ranges from -30° to +90°).
• Abnormal axis can suggest conditions like ventricular hypertrophy or conduction blocks

5. Examine P Waves and PR Interval

• P waves represent atrial depolarization; they should be upright and uniform in leads I and II.
• PR interval (start of P wave to start of QRS) should be 0.12–0.20 seconds. Prolongation may indicate AV block

6. Measure QRS Complex

• QRS represents ventricular depolarization; normal duration is less than 0.12 seconds.
• Look for abnormal widening (bundle branch block) or pathological Q waves (may indicate old myocardial infarction)

7. Assess ST Segment

• The ST segment should be isoelectric (flat).
• Elevation or depression may indicate myocardial ischemia or infarction

8. Evaluate T Waves and QT Interval

• T waves represent ventricular repolarization; they should be upright in most leads.
• QT interval (start of QRS to end of T wave) varies with heart rate but prolonged QT can predispose to arrhythmias

9. Look for U Waves (if present)

• Small waves after T waves; prominent U waves may indicate electrolyte disturbances or drug effects

10. Summarize Findings

• Integrate all observations to form a clinical impression and correlate with patient symptoms

Key Points of ECG Components

Component| Represents| Normal Duration/Appearance
---|---|---
P wave| Atrial depolarization| Small, upright, precedes each QRS
PR interval| Atrial to ventricular conduction| 0.12–0.20 seconds
QRS complex| Ventricular depolarization| <0.12 seconds, narrow
ST segment| Between ventricular depolarization and repolarization| Isoelectric (flat)
T wave| Ventricular repolarization| Upright in most leads
QT interval| Ventricular depolarization + repolarization| Varies with rate, usually <0.44 seconds

This structured approach helps ensure you do not miss important abnormalities and can interpret the ECG in clinical context accurately

. For detailed examples and practice, resources like Geeky Medics provide comprehensive guides and case studies.