How Do You Read an ECG?

How Do You Read An ECG?

Understanding how to read an electrocardiogram (ECG) can often mean the difference between life and death for your patients. ECGs can reveal various serious conditions such as thickened heart muscles, electrolyte imbalances, ischemia, heart attacks, and heart arrhythmias. Understanding an ECG can also accelerate the diagnostic process so your patient gets the treatment and intervention needed within a timely manner. Lastly, an EKG and an ECG are the same procedure, but with different spelling (elektrokardiogramm vs. electrocardiogram). The procedure records changes in the heart muscle over time. The activity is typically printed on a strip of paper via a 6 second rhythm strip to make interpretation easier.

The Nuts and bolts of the eCg strip

1. P-Wave – records electrical activity in the upper heart chambers and represents contractions
2. PR Interval – goes from the beginning of atrial polarization to beginning of ventricular depolarization
3. QRS Complex – records electrical activity in the lower heart chambers and includes the Q wave (first downstroke), R wave (first upward deflection), and S wave (first downward deflection)
4. T-Wave – also records upper heart activity, but represents relaxation

How do you read The Rhythm Strip?

Learning how to read an echocardiogram involves understanding the components listed above and how to put them together to read a strip. There are small and large boxes on the strip that measure time and distance. The heart’s activity is translated into line tracings consisting of dips and spikes that constitute waves.
The various components above make up the waves and by understanding the various elements and learning to measure them correctly, you can accurately interpret your EKG findings.

Understanding the ECG BASICS 

The first step in understanding how to properly read an ECG is to determine whether a heart rhythm is normal, which requires your understanding of the acronym A-D-D.

1. A is for Amplitude: Uncover the significance of wave height to measure the voltage of the beat
2. D is for Deflection: Decode the meaning of deflection and which lead it’s coming from
3. D is also for Duration: Grasp the importance of wave and interval duration (how long is it?)

How to Interpret the ECG

​A. The first step in interpreting the meaning behind an ECG strip is to review the P-waves. The P-waves are located at the beginning of the ECG cycle and they should be present and upright. If the P-wave is inverted or absent, it indicates an abnormality.

B. The next step is to measure the PR interval. The PR interval can be assessed  by simply counting the small boxes between where the P-wave begins and the QRS complex peaks and multiplying that number by .04..

C. Step three is to then measure the QRS complex by counting the small boxes from the beginning to the end of the complex and dividing that number by .04.

D. Next, you will want to examine the rhythm to determine whether it is regular, regularly irregular but in a recurrent pattern, or irregularly irregular and completely disorganized with no pattern.

E. Lastly, you will then need to determine the heart rate by counting the large boxes between the R waves and dividing that number by 300.

Take Your ECG Expertise to the Next Level

​Learning how to understand an ECG report allows you to provide an even higher level of urgent care to your patients. Here at Help-A-Heart CPR we offer an in-person ECG and Pharmacology class to better prepare and train individuals for reading and interpreting ECG's. 
Now is the time to learn how to interpret an ECG and take your patient care to the next tier. To learn more about ECG training with Help-A-Heart CPR, contact us today.