Electrocardiographs (ECGs or EKGs) provide data about the electrical activity of the heart. By placing a series of "leads" on a person's chest, the electrical activity of the heart can be recorded and analyzed in order to detect irregular heartbeats (arrhythmias) and other conditions. The figure below shows a normal EKG tracing for one cardiac cycle.
The P region represents electrical activity spreading through the atria. The QRS region represents electrical activity spreading through the ventricles. The T region represents electrical activity in the ventricles returning to rest.
-Suppose a person has a heart rate of 60 beats/min and that the start of the P region until the end of the T region represents one cardiac cycle. If the x axis in the EKG is time, approximately how much time passes between the start of the P region and the end of the T region?
A) 0.1 second
B) 1 second
C) 10 seconds
D) 60 seconds

Question

Electrocardiographs (ECGs or EKGs) provide data about the electrical activity of the heart. By placing a series of "leads" on a person's chest, the electrical activity of the heart can be recorded and analyzed in order to detect irregular heartbeats (arrhythmias) and other conditions. The figure below shows a normal EKG tracing for one cardiac cycle.
  The P region represents electrical activity spreading through the atria. The QRS region represents electrical activity spreading through the ventricles. The T region represents electrical activity in the ventricles returning to rest.
-Suppose a person has a heart rate of 60 beats/min and that the start of the P region until the end of the T region represents one cardiac cycle. If the x axis in the EKG is time, approximately how much time passes between the start of the P region and the end of the T region?
A) 0.1 second 
B) 1 second 
C) 10 seconds 
D) 60 seconds

Quizplus · Accepted Answer

The time between the start of the P region and the end of the T region represents one cardiac cycle. Since the heart rate is 60 beats/min, that means one cycle takes 1 second (60 seconds in a minute divided by 60 beats per minute = 1 second per beat). Therefore, approximately 1 second passes between the start of the P region and the end of the T region on the EKG.

Electrocardiographs (ECGs or EKGs) Provide Data About the Electrical Activity