What are the key components to include when reporting a formal sinus rhythm electrocardiogram (EKG)?

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Last updated: August 4, 2025View editorial policy

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Key Components for Reporting a Formal Sinus Rhythm EKG

A comprehensive EKG report for sinus rhythm should include rate, rhythm, intervals, axis, and waveform morphology assessment to accurately document cardiac electrical activity and identify any abnormalities that may impact patient morbidity and mortality.

Rate and Rhythm Assessment

  • Heart rate: Document the exact rate (normal sinus rhythm is 50-90 beats per minute) 1
  • Rhythm regularity: Note if the rhythm is regular or irregular
  • P wave morphology: Confirm upright P waves in leads II and aVF with consistent P-P intervals
  • P-QRS relationship: Verify each P wave is followed by a QRS complex with consistent PR intervals

Interval Measurements

  • PR interval: Normal range 120-200 ms
  • QRS duration: Normal range <120 ms in adults, <100 ms in children 4-16 years, <90 ms in children <4 years 2
  • QT interval: Measure and calculate corrected QT (QTc) using Bazett's formula (QTc = QT/√RR) 2
    • Normal QTc: <450 ms for men, <460 ms for women
    • Concerning values: ≥470 ms for men, ≥480 ms for women 2

Axis Determination

  • Frontal plane axis: Document the QRS axis (normal range -30° to +90°)
  • Note any axis deviation: Left axis deviation (<-30°), right axis deviation (>+90°), or extreme axis deviation (>+180°)

Waveform Morphology Analysis

  • P wave: Document duration (<120 ms), amplitude (<2.5 mm), and morphology
  • QRS complex: Assess for appropriate R wave progression in precordial leads
  • ST segment: Document position relative to baseline (elevation, depression, or isoelectric)
  • T wave: Note polarity, amplitude, and symmetry
  • U wave: Document if present

Conduction Assessment

  • Evaluate for conduction abnormalities: Document absence or presence of bundle branch blocks, fascicular blocks, or non-specific intraventricular conduction delays 2
  • Document absence or presence of pre-excitation patterns

Comparison with Previous ECGs

  • Note any significant changes according to comparison criteria 2:
    • No significant change (intervals remain normal or within 10% of previous values)
    • Significant rhythm change (new rhythm diagnosis, HR change ≥20 bpm)
    • New conduction abnormality
    • Significant repolarization change (QTc change ≥60 ms)

Clinical Correlation

  • Relate findings to patient's clinical presentation
  • Document any technical issues that may affect interpretation (e.g., artifact, lead placement issues)

Common Pitfalls to Avoid

  • Relying solely on computer interpretation: Always manually confirm key measurements, especially QT interval 3
  • Overlooking subtle abnormalities: Pay special attention to T wave morphology, which may indicate pathology even with normal intervals
  • Failing to use proper technique for QT measurement: Use the "Teach-the-Tangent" or "Avoid-the-Tail" method in leads II and V5 for accurate QT assessment 2
  • Not accounting for heart rate effects on intervals: Repeat ECG after rest or mild activity if heart rate is <50 or >90 bpm for more accurate QTc calculation 2

By systematically addressing all these components, your EKG report will provide a comprehensive assessment that helps guide clinical decision-making and potentially identifies conditions that could affect patient morbidity and mortality.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Electrocardiogram Recommendations

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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