long qt syndrome

WHY IS THE DISEASE NAMED LONG QT SYNDROME?

The name of the long QT syndrome refers to the QT-interval measured on the electrocardiogram (ECG or EKG for the German term "Elektrokardiogramm"). Your specialist may refer to long QT syndrome as Romano-Ward syndrome or Jervell, Lange-Nielsen syndrome (see point 3).

Epidemiology

Long QT syndrome (LQTS) remains an underdiagnosed disorder, especially because at least 10-15% of LQTS gene carriers have a normal QTc duration.

The prevalence of LQTS is difficult to estimate. However, given the currently increasing frequency of diagnosis, LQTS may be expected to occur in 1 in 10,000 individuals.

International

The occurrence of long QT syndrome internationally is similar to that in the United States.

Mortality/Morbidity

Mortality, morbidity, and responses to pharmacologic treatment differ in the various types of long QT syndrome (LQTS). This issue is under investigation.

LQTS may result in syncope and lead to sudden cardiac death, which usually occurs in otherwise healthy young individuals. LQTS is thought to cause about 4000 deaths in the United States each year. The cumulative mortality rate reaches approximately 6% by the age of 40 years.

Although sudden death usually occurs in symptomatic patients, it happens with the first episode of syncope in about 30% of the patients. This occurrence emphasizes the importance of diagnosing LQTS in the presymptomatic period.

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