What is Short QT Syndrome?
Short QT syndrome (SQTS) is a rare genetic condition that causes an unusually short duration of the QT interval on an electrocardiogram (ECG). The QT interval represents the time it takes for the heart's electrical system to recharge between beats.
In Short QT Syndrome, this period is too short, which can lead to a higher risk of abnormal heart rhythms (arrhythmias) that may cause fainting, seizures or sudden cardiac arrest.
Causes of short QT syndrome
Short QT syndrome is usually caused by genetic mutations that affect the ion channels in the heart, which control its electrical activity. These mutations result in a shortened QT interval. In most cases, SQTS is inherited because one copy of the altered gene from either parent is enough to cause the condition.Risk factors for short QT syndrome
The main risk factor for Short QT Syndrome is a family history of the condition. SQTS is usually inherited. People with a known family history of sudden cardiac arrest, arrhythmias or SQTS may be at higher risk.
People with certain genetic mutations or abnormalities in heart cell ion channels are also at risk for developing this condition.
Symptoms of short QT syndrome
Short QT Syndrome may cause symptoms like:
- Palpitations
- Dizziness
- Fainting
- Seizures due to the irregular heart rhythms
In some cases, there may be no symptoms until a life-threatening arrhythmia, such as ventricular fibrillation, causes sudden cardiac arrest.
Many people with SQTS may remain undiagnosed until a cardiac event occurs.
Diagnosing short QT syndrome
Short QT Syndrome is diagnosed through an electrocardiogram (ECG), which shows a shortened QT interval. Genetic testing may also be performed to identify mutations in ion channel genes associated with SQTS. Additionally, a thorough family history is taken, and other heart-related tests may be conducted to assess the risk of arrhythmias and sudden cardiac arrest.
Treatment of Short QT Syndrome
Treatment for Short QT Syndrome often involves medication to control arrhythmias, like antiarrhythmic drugs.
In more severe cases, a defibrillator (implantable cardioverter-defibrillator, or ICD) may be implanted to prevent life-threatening arrhythmias and sudden cardiac arrest. Lifestyle modifications and regular monitoring are also important for managing the condition.