Abstract
Corrected QT interval (QTc) is one of the basic parameters on standard 12-lead ECG. There are some difficulties associated with the accurate QTc measurement.
The "teach-the-tangent" is the most frequently used method of QT measurement. Generally, QTc is calculated using Bazett's formula.
The morphology of T wave is also important. The finding of a prolonged QTc may be a sign of long QT syndrome and should be assessed by cardiologist