ECG Monitoring UPDATED Exam
Questions and CORRECT Answers
What are ECG's used for? - CORRECT ANSWER - Determining HR, heart rhythm,
evaluating conduction abnormalities & heart chamber enlargement by evaluating the PQRST
complexes
Depolarization - CORRECT ANSWER - Electrical stimuli of heart muscle causing
contraction, systole when ventricle depolarizes, electrolytes Na+ & Ca+ move into cell
Repolarization - CORRECT ANSWER - Heart muscle relaxation occurs when K+ moves
out of the cardiac muscle cells, leading to the relaxing of cardiac muscle, diastole when ventricle
repolarizes
What is the order electricity moves through the heart? - CORRECT ANSWER - SA node,
AV node, bundle of his, right bundle branch, purkinje fibers
What does the AV node do? - CORRECT ANSWER - It slows things down with
electricity, makes it so all 4 chambers don't contract at the same time
Asystole - CORRECT ANSWER - Without a heartbeat
What position do you have the animal in to do an ECG? - CORRECT ANSWER - Right
lateral recumbancy
How many leads are there? - CORRECT ANSWER - 12
What are all the different leads? - CORRECT ANSWER - Limb leads = I, II, III, aVR,
aVL, aVF, Chest leads = V1, V2, V3, V4, V5, V6
, What do leads look at? - CORRECT ANSWER - The leads are looking at different angles
of the heart, it is a 2D printout of the heart
What does the P wave represent? - CORRECT ANSWER - When the atrium is contracting
(depolarization of the atrium), its duration indicates the time required for an impulse to pass from
the SA node to the AV node
How do you measure the P wave? - CORRECT ANSWER - Height = from the upper edge
of the baseline to the top of the P wave, Width = at the inside, from the start to the end of the
deflection from the baseline
What is the P-R interval? - CORRECT ANSWER - Reflects activation of the AV junction
How is the P-R interval measured? - CORRECT ANSWER - From the beginning of the P
wave to the beginning of the Q wave (R wave if no Q wave is present)
What does the QRS complex represent? - CORRECT ANSWER - Represents
depolarization of the ventricles
How is the QRS complex measured? - CORRECT ANSWER - Width = measured from
the beginning of the first deflection to the end of the final deflection of the complex
Does every QRS complex have a Q, R, & S wave? - CORRECT ANSWER - No, it is
normally just considered one wave
What does the S-T segment represent? - CORRECT ANSWER - The time interval from
the end of the QRS interval to the onset of the T wave, the early phase of ventricular
repolarization
What does the T wave represent? - CORRECT ANSWER - The first major deflection
following the QRS complex and represents repolarization of the ventricles
Questions and CORRECT Answers
What are ECG's used for? - CORRECT ANSWER - Determining HR, heart rhythm,
evaluating conduction abnormalities & heart chamber enlargement by evaluating the PQRST
complexes
Depolarization - CORRECT ANSWER - Electrical stimuli of heart muscle causing
contraction, systole when ventricle depolarizes, electrolytes Na+ & Ca+ move into cell
Repolarization - CORRECT ANSWER - Heart muscle relaxation occurs when K+ moves
out of the cardiac muscle cells, leading to the relaxing of cardiac muscle, diastole when ventricle
repolarizes
What is the order electricity moves through the heart? - CORRECT ANSWER - SA node,
AV node, bundle of his, right bundle branch, purkinje fibers
What does the AV node do? - CORRECT ANSWER - It slows things down with
electricity, makes it so all 4 chambers don't contract at the same time
Asystole - CORRECT ANSWER - Without a heartbeat
What position do you have the animal in to do an ECG? - CORRECT ANSWER - Right
lateral recumbancy
How many leads are there? - CORRECT ANSWER - 12
What are all the different leads? - CORRECT ANSWER - Limb leads = I, II, III, aVR,
aVL, aVF, Chest leads = V1, V2, V3, V4, V5, V6
, What do leads look at? - CORRECT ANSWER - The leads are looking at different angles
of the heart, it is a 2D printout of the heart
What does the P wave represent? - CORRECT ANSWER - When the atrium is contracting
(depolarization of the atrium), its duration indicates the time required for an impulse to pass from
the SA node to the AV node
How do you measure the P wave? - CORRECT ANSWER - Height = from the upper edge
of the baseline to the top of the P wave, Width = at the inside, from the start to the end of the
deflection from the baseline
What is the P-R interval? - CORRECT ANSWER - Reflects activation of the AV junction
How is the P-R interval measured? - CORRECT ANSWER - From the beginning of the P
wave to the beginning of the Q wave (R wave if no Q wave is present)
What does the QRS complex represent? - CORRECT ANSWER - Represents
depolarization of the ventricles
How is the QRS complex measured? - CORRECT ANSWER - Width = measured from
the beginning of the first deflection to the end of the final deflection of the complex
Does every QRS complex have a Q, R, & S wave? - CORRECT ANSWER - No, it is
normally just considered one wave
What does the S-T segment represent? - CORRECT ANSWER - The time interval from
the end of the QRS interval to the onset of the T wave, the early phase of ventricular
repolarization
What does the T wave represent? - CORRECT ANSWER - The first major deflection
following the QRS complex and represents repolarization of the ventricles
