Enter the QT interval and the heart rate into the calculator to determine the corrected QT interval (QTc) using the Fridericia formula. This calculator helps to assess the risk of arrhythmias by correcting the QT interval for heart rate.
Fridericia QTc Formula
The following formula is used to calculate the corrected QT interval (QTc) using the Fridericia method.
QTc = QT / (RR interval )^{(1/3)}Variables:
- QTc is the corrected QT interval (milliseconds)
- QT is the measured QT interval (milliseconds)
- RR interval is the time between heartbeats, calculated as 60 / heart rate (seconds)
To calculate the corrected QT interval (QTc) using the Fridericia formula, divide the measured QT interval by the cube root of the RR interval in seconds.
What is the Fridericia QTc?
The Fridericia QTc is a formula used to correct the QT interval for heart rate variability. The QT interval is the time from the start of the Q wave to the end of the T wave in the heart’s electrical cycle. A prolonged QT interval can be a risk factor for ventricular arrhythmias. The Fridericia correction is one of several methods used to adjust the QT interval for heart rate, providing a more accurate assessment of the heart’s electrical stability.
How to Calculate Fridericia QTc?
The following steps outline how to calculate the Fridericia Corrected QT Interval (QTc).
- First, measure the QT interval (QT) in milliseconds.
- Next, measure the heart rate in beats per minute.
- Calculate the RR interval in seconds as 60 divided by the heart rate.
- Use the Fridericia formula: QTc = QT / (RR interval in seconds)^(1/3).
- Finally, calculate the corrected QT interval (QTc) in milliseconds.
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem :
Use the following variables as an example problem to test your knowledge.
QT interval (QT) = 360 milliseconds
Heart rate = 75 beats per minute
