30 year old female with a history of syncope.
- Dramatically prolonged QT interval
- Sinus rhythm
- Prolonged QT interval
Discussion: When a tangent line is drawn from the steepest portion of the descending limb of the T-wave, this intersects with the baseline and a point closest to the following QRS. When this point falls to the right of midline as bordered by the two adjacent QRS is, this identifies a corrected QT interval that is high risk and is greater than 500 ms.