The keys to the correct ECG diagnosis of the long QT syndrome are the following:
- The recognition of the various ECG presentations of the long QT syndromes
- A high index of suspicion based on the history and clinical presentation
- The ability to rule out other causes of the ECG abnormality such as hypopotassemia, hypocalcemia, and a variety of cardioactive drugs, most notably the class 1a and class 3 antiarrhythmc agents.