Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) short QT syndrome ?
    ### Response:
    Short QT syndrome is a condition that can cause a disruption of the heart's normal rhythm (arrhythmia). In people with this condition, the heart (cardiac) muscle takes less time than usual to recharge between beats. The term "short QT" refers to a specific pattern of heart activity that is detected with an electrocardiogram (EKG), which is a test used to measure the electrical activity of the heart.
    