A Thorough Relias Dysrhythmia Test Resource Featuring
All Correct Solutions
SA Node. - correct answers ✔️✔️What is the pacemaker of the heart normally?
Upper right atrium. - correct answers ✔️✔️Where does the SA node originate?
SA node -> atria -> AV node -> bundle of his -> bundle branches -> purkinje fibers -> ventricles. - correct
answers ✔️✔️What is the pathway of conduction in the heart?
Decreased firing of the SA node and slowed impulse conduction of the AV node. - correct answers
✔️✔️What does stimulation of the vagus nerve cause?
Increased firing of the SA node and increased impulse through the AV node, and cardiac contractility. -
correct answers ✔️✔️What does stimulation of the sympathetic nerves cause?
Time for the passage of the electrical impulse through the atrium causing atrial depolarization
(contraction). - correct answers ✔️✔️What does the P wave represent?
0.06 - 0.12. - correct answers ✔️✔️What is the normal P wave duration?
, Disturbance in conduction within the atria. - correct answers ✔️✔️What is a possible variation cause of
a P wave?
The measure from the beginning of the P wave to the beginning of the QRS complex, represents time
taken for impulse to spread through the atria, AV node, and bundle of his, the bundle branches and
purkinje fibers, to a point of immediately preceding ventricular contraction. - correct answers
✔️✔️What does the PR interval represent?
0.12 - 0.20. - correct answers ✔️✔️What is the normal PR interval?
Disturbance in conduction usually in the AV node, bundle of his, or bundle branches but can be atria as
well. - correct answers ✔️✔️What is a possible variation cause with PR interval?
Measure from beginning to end of QRS complex, represent time taken for depolarization (contraction)
of both ventricles (systole). - correct answers ✔️✔️What does the QRS interval represent?
<0.12. - correct answers ✔️✔️What is the normal QRS interval?
Disturbance in conduction in the bundle branches or in the ventricles. - correct answers ✔️✔️What is a
possible variation cause with the QRS interval?
Measure from the S wave of the QRS complex to the beginning of the T wave; represents time between
ventricular depolarization and repolarization (Diastole); should be isoelectric (flat). - correct answers
✔️✔️What does the ST Segment represent?
0.12. - correct answers ✔️✔️What is the normal ST segment?
Disturbance usually caused by ischemia, injury or infarction. - correct answers ✔️✔️What is a possible
variation cause with the ST segment?
Represents time for ventricular repolarization, should be upright. - correct answers ✔️✔️What does the
T wave represent?
All Correct Solutions
SA Node. - correct answers ✔️✔️What is the pacemaker of the heart normally?
Upper right atrium. - correct answers ✔️✔️Where does the SA node originate?
SA node -> atria -> AV node -> bundle of his -> bundle branches -> purkinje fibers -> ventricles. - correct
answers ✔️✔️What is the pathway of conduction in the heart?
Decreased firing of the SA node and slowed impulse conduction of the AV node. - correct answers
✔️✔️What does stimulation of the vagus nerve cause?
Increased firing of the SA node and increased impulse through the AV node, and cardiac contractility. -
correct answers ✔️✔️What does stimulation of the sympathetic nerves cause?
Time for the passage of the electrical impulse through the atrium causing atrial depolarization
(contraction). - correct answers ✔️✔️What does the P wave represent?
0.06 - 0.12. - correct answers ✔️✔️What is the normal P wave duration?
, Disturbance in conduction within the atria. - correct answers ✔️✔️What is a possible variation cause of
a P wave?
The measure from the beginning of the P wave to the beginning of the QRS complex, represents time
taken for impulse to spread through the atria, AV node, and bundle of his, the bundle branches and
purkinje fibers, to a point of immediately preceding ventricular contraction. - correct answers
✔️✔️What does the PR interval represent?
0.12 - 0.20. - correct answers ✔️✔️What is the normal PR interval?
Disturbance in conduction usually in the AV node, bundle of his, or bundle branches but can be atria as
well. - correct answers ✔️✔️What is a possible variation cause with PR interval?
Measure from beginning to end of QRS complex, represent time taken for depolarization (contraction)
of both ventricles (systole). - correct answers ✔️✔️What does the QRS interval represent?
<0.12. - correct answers ✔️✔️What is the normal QRS interval?
Disturbance in conduction in the bundle branches or in the ventricles. - correct answers ✔️✔️What is a
possible variation cause with the QRS interval?
Measure from the S wave of the QRS complex to the beginning of the T wave; represents time between
ventricular depolarization and repolarization (Diastole); should be isoelectric (flat). - correct answers
✔️✔️What does the ST Segment represent?
0.12. - correct answers ✔️✔️What is the normal ST segment?
Disturbance usually caused by ischemia, injury or infarction. - correct answers ✔️✔️What is a possible
variation cause with the ST segment?
Represents time for ventricular repolarization, should be upright. - correct answers ✔️✔️What does the
T wave represent?
