ECG: Corrected QT

Posted by Nyoman Ririn Chandrika on Monday, February 29, 2016
Hello again! Finally, we're back with our newest android-based application. What is it this time? Yap, still wandering around ECG thingy, now we proudly present the ECG: Corrected QT application. 

Around many aspects to interpret in ECG recording, QT interval is one of the most important. QT interval is the duration between the beginning of Q wave and the end of the T wave. Its duration in ECG recording represents the time taken for ventricular depolarization and repolarization. An abnormally prolonged QT interval is associated with an increased risk of ventricular arrhythmias, especially Torsades de Pointes. Meanwhile, the recently described congenital short QT syndrome has been found to be associated with an increased risk of paroxysmal atrial and ventricular fibrillation and sudden cardiac death.

On the other hand, QT interval is affected is affected by heart rates. The QT interval is inversely proportional to heart rate. It will shorten at faster heart rates and lengthens at slower heart rates. Then, how can we surely estimate if one QT interval is normal? It is recommended to interpret the normal values of QT interval based on the corrected QT (QTc), in order to avoid the effects of heart rate on QT values. By calculating the QTc, we can do a comparison of QT values over time at different heart rates and improves detection of patients at increased risk of arrhythmias. By simply click this link or the badge below, estimating the corrected QT interval would never be this easy!

Get it on Google Play

Why should you choose ECG: Corrected QT?
- It is simple and very easy to use.
- The calculation is precise and accurate.
- Based on 3 most commonly used formulas, Bazett, Fredericia, and Framingham.
- It is totally free!

The corrected QT interval (QTc) will estimate the QT interval at a heart rate of 60 beats per minute. In order to achieve the QTc value, you need to input the QT interval (in msec) and the heart rate (in beats per minute). QT interval should be measured in either lead II or V5-6. Several successive beats should be measured, with the maximum interval taken. After that, the application will automatically do the math for you, using 3 available formula, namely Bazett, Fredericia and Framingham formula. Bazett's formula is the most commonly used because of its adequate correction for heart rates ranging from 60 - 100 bpm. But it over-corrects at heart rates >100 bpm and under-corrects at heart rates <60 bpm. At heart rates outside of the 60 - 100 bpm range, the Frederica or Framingham corrections are more accurate and should be used instead. 

The interpretation of QTc value is as follows. QTc is prolonged if >440 ms in men or >460 ms in women while QTc is abnormally short if <350 ms. QTc >500 ms is associated with increased risk of Torsades de Pointes. Now, based on the QTc result, the physician can determine whether the patient has an increased risk of arrhythmia and planning further diagnostic step and therapy. Here is the preview of our apps on Google Nexus 4.

ECG: Corrected QT PreviewECG: Corrected QT Preview

We hope you found this brief review helpful. Don't forget to download the application and give a positive review on play store! Got something on your mind? Don't hesitate to contact us at 

See you real soon and have a nice day!

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