Cardiology

Corrected QT (QTc)

Calculates the QTc interval using Bazett's formula.

Parameters

ms
bpm

Corrected QT (QTc) Result

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FormulaBazett's Formula: QTc = QT / √RR (Where RR interval in seconds = 60 / HR)

Clinical Pearls

A prolonged QTc indicates delayed ventricular repolarization and is a major risk factor for ventricular tachyarrhythmias, particularly Torsades de Pointes (TdP). It can be congenital or acquired (often due to medications or electrolyte abnormalities).

Limitations

Bazett's formula overcorrects at high heart rates (>90 bpm) and undercorrects at low heart rates (<60 bpm). In these scenarios, other formulas (e.g., Fridericia, Framingham) may be more accurate.