QTc
Medical abbreviation · Cardiology
| Stands for | Corrected QT interval |
|---|---|
| Categories | Medical |
QTc stands for Corrected QT interval, a cardiology abbreviation.
QT interval on the ECG adjusted for heart rate, since the raw QT shortens as the heart speeds up. Values above about 450 ms in men and 460 ms in women are prolonged, and a QTc above 500 ms markedly raises the risk of torsades de pointes.
Example: QTc 512 ms on day 3 of azithromycin and ondansetron; both stopped and electrolytes repleted.
Usage notes
Bazett's formula (QT divided by the square root of the RR interval), published in 1920, is the most widely used correction but overcorrects at fast heart rates; the Fridericia, Framingham and Hodges formulas are alternatives. Pharmacists and hospital systems flag QTc when QT-prolonging drugs are combined. A wide QRS from bundle branch block lengthens the QT without the same arrhythmic risk.
Related abbreviations
More cardiology abbreviations
- PTS – Post-thrombotic syndrome
- PVC – Premature ventricular contraction
- PVD – Peripheral vascular disease
- PVI – Pulmonary vein isolation
- PVR – Pulmonary vascular resistance
- QRS – QRS complex
- RA – Right atrium
- RAD – Right axis deviation
- RBBB – Right bundle branch block
- RCA – Right coronary artery
- RCM – Restrictive cardiomyopathy
- RFA – Radiofrequency ablation
See all 229 cardiology abbreviations →
This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.