Blog Post

#016



Reading medical devices may seem difficult to people with all of the different components and abbreviations on its display screen. EKG/ECG is one of the harder medical devices to understand since it is uncommon for people to own at home. However, this blog would teach you how to read and understand one correctly.


Must Know Abbreviations:

  • HR: Heart Rate

  • BP: Blood Pressure (SYS: Systolic, DIA: Diastolic)

  • SpO2: Oxygen Saturation

  • RR: Respiration Rate


Heart Rate and Rhythm:

  • Regular rhythm is 300/number of boxes between the R waves

  • Irregular rhythm is the amount of QRS complexes in 10 secs X 6


What is a P-wave?

P-wave: The first small upright deflection, looks like a small hill on the monitor

  • Every P wave should come before each QRS complex: Regular spacing = regular rhythm, Inconsistent spacing = irregular rhythm 

The typical PR interval is around 0.12-0.20 seconds


What is a QRS Complex?

QRS Complex: Combination of the Q, R, and S waves, represents the electrical impulse of the ventricles (ventricular depolarization) 

The typical width of a QRS complex is less than 0.12 seconds

  • If width is higher bigger than 0.12 seconds, it could indicate a block or ventricular beat

  • Look for abnormal waves or shapes. It could indicate heart damage, most likely from a heart attack


What is a ST Segment, T-Wave, & QT Interval?

  • ST Segment: The end of the QRS complex and the beginning of the T-Wave

    • The ST Segment should always be flat, otherwise it suggests signs of ischemia

  • T Wave: The second small upright deflection, similar to a P-wave

    • Represents the ventricular repolarization before the next heartbeat

    • Should be asymmetrical, otherwise it suggests signs of cardiac issues

  • QT Interval: The start of the QRS complex to the end of the T-wave

    • Includes the QRS complex, ST Segment, and T-wave

    • Should be less than 0.36-0.44 seconds, or can suggest signs of dangerous arrhythmia 


What is an Electrical Axis?

  • Electrical Axis: The overall direction of heart electrical flow

    • Normal Axis is from 0° to 90°

  • Look for any abnormal signs or discrepancies, could suggest heart attack, blocks, arrhythmias, etc.


EKG/ECG Checklist:

  1. Make sure the device shows all 12 leads (12 different views of the heart)

  2. Check the heart rate and blood pressure (60-100 beats, 120/80 mmHg)

  3. Check that the P-wave is like a small, symmetrical hill with regular spacing and the PR interval is around 0.12-20 seconds

  4. Check that the width of the QRS complex is less than 0.12 seconds and has no abnormal shapes

  5. Check that ST Segment is always flat, T-wave is like the P-wave but larger, more rounded, and slightly asymmetrical, and the QT interval is around 0.36-0.44 seconds

  6. Check that the overall direction of the heart flow is around 0° to 90°

How to Read an EKG/ECG Monitor