Short QT Syndrome (SQTS)
is a congenital abnormality in the electrical activity within the muscle cells
of the heart. SQTS is
named because of it diagnsotic characteristics on the electrocardiogram (ECG).
To understand what a short QT is we must first understand what
information is found on a ECG.
represents the electrical activity of the heart. As the heart
beats, the electrical activity is recorded on surface electrodes.
This electrical information is translated into wave patterns on paper
that can be read by a physician. The direction and duration of the
wave patterns help doctors determine normal from abnormal electrical
patterns. An ECG can demonstrate abnormal patterns revealing old
or new heart attacks, need for a pace maker, and important to our
discussion, Short QT Syndrome.
The normal ECG below has multiple wave forms.
All of these wave forms are reviewed to determine normal tracing from an abnormal
We will concentrate on a single cardiac cycle in a
single wave form (single lead) represented by the figure below.
The heart is made up of four chambers. Two
of these chambers are the right and left atria. They pump blood into the
right and left ventricles respectively. The activity of the atria
is represented by the P-wave. After the atria contract the right
ventricles pumps blood into the lungs and the left
ventricle pumps blood to the rest of the body. This event is
simultaneous and is represented by the QRS. The final wave form
seen below is the T-wave. The end of the T-wave coincides with
completion of heart muscle activity. The heart is now ready to
This basic understanding about ECGs will help with
the next section: What Is A QT Interval