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QTc Fridericia Correction: Explanation and Clinical Context The Fridericia formula is used to correct the QT interval for heart rate: QTcF = QT / (RR^1/3), where RR is the interval between heartbeats in seconds. It provides a more accurate correction than Bazett's formula, especially at extreme heart rates. QTc prolongation is associated with increased risk of ventricular arrhythmias, including Torsades de Pointes, and sudden cardiac death.
Clinical interpretation uses sex-specific normal limits: typically <450 ms for men and <460 ms for women. The Fridericia correction is recommended in clinical trials and drug safety studies for precise QT interval evaluation.
Evidence & references1 primary source mapped
- Source 1
Fridericia LS. Die Systolendauer im Elektrokardiogramm bei normalen Menschen und bei Herzkranken. Acta Med Scand. 1920;53:469-486.
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