Corrected QT Interval (QTc)
The Corrected QT (QTc) Interval Calculator helps estimate the heart’s electrical recovery time adjusted for heart rate. It’s especially useful for evaluating patients with potential arrhythmias or on medications that prolong QT interval. Enter QT and R-R interval to get QTc using Bazett’s formula.
Heart Electrical Cycle Interval
Bazett’s Formula for QTc
Where:
- QT is the measured QT interval in seconds
- RR is the R-R interval in seconds
- QTc is the corrected QT interval
This formula adjusts the QT interval based on heart rate, giving a better risk assessment for arrhythmias.
The QT interval varies with heart rate; thus, correction formulas like Bazett’s are used in cardiology to normalize the QT interval. Prolonged QTc can indicate higher risk of ventricular arrhythmias such as Torsades de Pointes. This calculator is helpful in clinical evaluations and medication monitoring.
Example:
- If $$QT = 0.42 sec$$ and $$RR = 0.9 sec$$
- $$QTc = 0.42 / √0.9 ≈ 0.44 sec$$