12-Lead ECG Interpretation

Rate & Rhythm

• Heart Rate: ~45-50 bpm - Sinus Bradycardia
• Rhythm: Regular with mild R-R variability consistent with sinus arrhythmia
• Every P wave is followed by a QRS (1:1 conduction)

Intervals

Axis

• Normal axis (~+30° to +60°)
• Lead I positive, aVF positive, II strongly positive

P Waves

• Upright in I, II, aVF; inverted in aVR - normal sinus morphology
• No signs of atrial enlargement (no P-pulmonale or P-mitrale)

QRS Morphology

• No bundle branch block (narrow QRS)
• No pathological Q waves
• Normal R-wave progression across precordial leads (V1 to V6)

ST Segments & T Waves

• Mild concave ST elevation (~1 mm) in V1-V3 - this is the key finding
  • Concave ("saddle-back" or "smiley face") morphology
  • No reciprocal ST depression in inferior/lateral leads
  • This pattern is consistent with Benign Early Repolarization (BER) - a common normal variant, especially in young males or athletes
• No ST depression in any lead
• Prominent but symmetric upright T waves in precordial and inferior leads

Summary

Clinical Correlation Needed

• If the patient has chest pain - must rule out Brugada pattern (Type 1: coved ST elevation >2mm with T-wave inversion in V1-V2) or anterior STEMI
• If asymptomatic young individual - early repolarization is very likely a normal variant
• A prior ECG comparison would be invaluable
• The sinus bradycardia may reflect high vagal tone (athletic heart, young person, or sleep state)

⚠️ Disclaimer: This is an AI interpretation for educational purposes only. All ECGs must be formally reported by a qualified physician and correlated with the patient's clinical presentation, history, and prior ECGs.