Long QT
Penny Wilson, MD, and Heidi James, MD
- Long QT is a potentially deadly condition
- QT >450 ms is prolonged and >500 ms is high risk for conversion to torsades
- Unless the heart rate is exactly 60, use the calculated QTc
- Prolonged QT may be due to
- Genetic/congenital factors
- Hypomagnesemia, hypocalcemia, hypokalemia
- Myocardial abnormalities
- Medications
- Management may include correction of underlying causes, beta blockers, exercise restriction, or implantable cardiac defibrillator
