Does LQTS have any symptoms?
Nearly half of people with congenital (genetic) Long QT Syndrome never experience symptoms. That means the condition can exist silently for years, even decades, without causing any noticeable symptoms, An arrhythmia caused by LQTS could be described as a latent threat as it something that always has the potential to happen but may not ever manifest.
Fainting is the most common symptom of Long QT Syndrome. Normally people will know when they are going to faint as they'll feel dizzy, sick, blurred vision or go clammy. If someone faints due to an arrhythmia, it will be abrupt, without any warning.
Long QT can present with a variety of symptoms, which may vary from person to person. After fainting, a 'seizure disorder' is one of the most common red flags for Long QT Syndrome. When someone has a seizure, doctors are quick to check the brain with an EEG but often overlook the heart and and ECG. For many people the condition is only detected during routine medical checks or ECGs.