Telemetry BAMC Exam Questions and
Answers
Conduction System
sinoatrial node (SA)-->atrioventricular node (AV)-->bundle of His--->Purkinje fibers
SA node: located high in the right atrium, Normal pacemaker of the heart because
it possesses the fastest rate of automaticity, approximately 60 to 100 bpm.
AV node: located low in the right atrium, delays impulse from atria for 0.04
seconds to allow atrial contraction and synchronizes atrial contribution to
ventricular pumping. Then sent to ventricles via the bundle of His; can serve as a
backup pacemaker; the inherent rate of automaticity is 40-60 bpm.
Purkinje Fibers: provides for the depolarization; followed by ventricular
contraction and ejection of blood out of the ventricles. The intrinsic rate of 20 to
40 bpm.
P wave
indicates impulse originate at the SA node and the atrial are normally depolarized.
Duration: 0.10 seconds
PR Interval
,represents the time required for the electrical impulse to travel from the SA node,
through the atria, AV node, Bundle of his, bundle branches and Purkinje fibers;
measures from the beginning of the P wave to the beginning of the QRS complex.
Duration: 0.12-0.20 seconds.
Isoelectric line
flat line that indicates no electrical activity, flat line between complexes
QRS complex
represents the time required for the electrical impulse to depolarize the
ventricles. Measured from the Q wave where the line leaves baseline to the S
where the line returns to baseline; duration: 0.06-0.12 seconds; duration of
greater than 0.12 seconds is considered abnormal.
ST segment
represents the end of ventricle depolarization and beginning of ventricular
repolarization. measured from the end of the QRS complex and ends with the
onset of the T wave. Duration: 0.08 seconds.
T wave
represents the latter phase of ventricular repolarization; measured from the
beginning as the deflection slopes upward from the ST segment and ends with the
line returning to baseline. Amplitude: < 5mm
Rhythm Analysis
1. Rate = count R peaks x 10 (should be 60-100 bpm)
2. P wave = SA node not firing if absent
3. Rhythm = regular
4. PRI (P rate interval) = start P to dip Q (0.12-0.20)
5. QRS = < 0.12
, ECG measurement
EKG measurement
Method #1 calculating the heart rate (HR)
for regular rates, count the number of small squares between two complexes and
divide into 1500 OR count the number of large squares between two complexes
and divide into 300
Method #2 calculating HR
for irregular or regular rates, use the 3 second or 6 second markers on the EKG
paper; count the number of complexes in a 3 second strip ( 15 large squares) and
multiply by 20 OR count the number of complexes in a 6 second strip (30 large
squares) and multiply by 10
EKG graph paper with vertical lines in the upper margin are what?
are measures of time standard to all EKG graph paper; the distance between 2
"tic" marks is 3 seconds, 3 "tic" marks equal 6 seconds
Normal Sinus Rhythm
Answers
Conduction System
sinoatrial node (SA)-->atrioventricular node (AV)-->bundle of His--->Purkinje fibers
SA node: located high in the right atrium, Normal pacemaker of the heart because
it possesses the fastest rate of automaticity, approximately 60 to 100 bpm.
AV node: located low in the right atrium, delays impulse from atria for 0.04
seconds to allow atrial contraction and synchronizes atrial contribution to
ventricular pumping. Then sent to ventricles via the bundle of His; can serve as a
backup pacemaker; the inherent rate of automaticity is 40-60 bpm.
Purkinje Fibers: provides for the depolarization; followed by ventricular
contraction and ejection of blood out of the ventricles. The intrinsic rate of 20 to
40 bpm.
P wave
indicates impulse originate at the SA node and the atrial are normally depolarized.
Duration: 0.10 seconds
PR Interval
,represents the time required for the electrical impulse to travel from the SA node,
through the atria, AV node, Bundle of his, bundle branches and Purkinje fibers;
measures from the beginning of the P wave to the beginning of the QRS complex.
Duration: 0.12-0.20 seconds.
Isoelectric line
flat line that indicates no electrical activity, flat line between complexes
QRS complex
represents the time required for the electrical impulse to depolarize the
ventricles. Measured from the Q wave where the line leaves baseline to the S
where the line returns to baseline; duration: 0.06-0.12 seconds; duration of
greater than 0.12 seconds is considered abnormal.
ST segment
represents the end of ventricle depolarization and beginning of ventricular
repolarization. measured from the end of the QRS complex and ends with the
onset of the T wave. Duration: 0.08 seconds.
T wave
represents the latter phase of ventricular repolarization; measured from the
beginning as the deflection slopes upward from the ST segment and ends with the
line returning to baseline. Amplitude: < 5mm
Rhythm Analysis
1. Rate = count R peaks x 10 (should be 60-100 bpm)
2. P wave = SA node not firing if absent
3. Rhythm = regular
4. PRI (P rate interval) = start P to dip Q (0.12-0.20)
5. QRS = < 0.12
, ECG measurement
EKG measurement
Method #1 calculating the heart rate (HR)
for regular rates, count the number of small squares between two complexes and
divide into 1500 OR count the number of large squares between two complexes
and divide into 300
Method #2 calculating HR
for irregular or regular rates, use the 3 second or 6 second markers on the EKG
paper; count the number of complexes in a 3 second strip ( 15 large squares) and
multiply by 20 OR count the number of complexes in a 6 second strip (30 large
squares) and multiply by 10
EKG graph paper with vertical lines in the upper margin are what?
are measures of time standard to all EKG graph paper; the distance between 2
"tic" marks is 3 seconds, 3 "tic" marks equal 6 seconds
Normal Sinus Rhythm
