The next part of the tracing is a short downward section connected to a tall upward section. The ST segment indicates the amount of time from the end of the contraction of the ventricles to the beginning of the rest period before the ventricles begin to contract for the next beat. The T wave indicates the resting period of the ventricles. Variations in size and length of the different parts of the tracing may be significant. The tracing for each lead of a 12-lead EKG will look different, but will have the same basic components as described above.
Atrial fibrillation is a type of arrthymia.
The atria quiver instead of contracts. The electrical signals then arrive in the ventricles in an irregular fashion. About 15 percent of strokes occur in persons with atrial fibrillation. Aspirin, warfarin, and cardiac medications may be used to treat atrial fibrillation. Click here to view the Online Resources page of this Web.