CCRN AACN 2024/2025 EXAM 330
QUESTIONS AND CORRECT ANSWERS
atrial fibrillation adverse consequences - ANSWER- 1. decreased cardiac
output due to loss of atrial kick, rapid ventricular rate, irregular ventricular
rhythm
2. tachycardia induced cardiomyopathy - in rapid afib for prolonged period
of time
3. thromboembolism
right bundle branch - ANSWER- -right side of the interventricular septum
and right ventricle
-impulse travels slower as the right ventricle is smaller/thinner
left bundle branch - ANSWER- two main divisions: anterior fascicle and
posterior fascicle carrying impulses to the left ventricle
PR interval - ANSWER- delay of AV node to allow filling of ventricles
,QRS complex - ANSWER- ventricular depolarization
shape depends on the lead that is being monitored and the ventricular
activation device
T wave - ANSWER- ventricular repolarization
normally in the same direction as the QRS
upright, flat, inverted
pathologies of T wave - ANSWER- MI, E/L levels, drug effect, myocardial
disease, and lead being recorded
u wave - ANSWER- repolarization of the purkinje fibers
SHOULD BE POSITIVE especially when T wave is positive
large u waves can be seen when repolarization is abnormally prolonged -
E/L imbalances like hypokalemia, hypocalcemia, hypomagnesemia, IICP,
LVH, certain medications
ST segment - ANSWER- early ventricular repolarization
should be at isoelectric line
,J point - ANSWER- where QRS complex ends and ST segment begins
QT interval - ANSWER- ventricular depolarization and repolarization varies
with age, gender, and heart rate
beginning of the QRS to the end of the T wave
QT must be corrected to a HR of 60 bpm
QTc - ANSWER- corrected QT interval =
QT/(square root of R-R interval)
normalizes for HR
long QTc --> torsades, ventricular arrhythmia, Vfib
vertical axis - ANSWER- each small box is 1mm or 0.1 mV
each large box is 5mm or 0.5 mV
most common complication of ischemic heart disease and MI - ANSWER-
dysrhythmias
best leads for differentiating wide QRS rhythms - ANSWER- v1 and v6
v1 and v6 - ANSWER- helps to differentiate VTACH from SVT with
aberrant intraventricular conduction
, helps to recognize right and left bundle branch blocks
differentiates between right and left ventricular ectopy
differentiates between right and left ventricular pacing
v1 and v6 placement - ANSWER- v1 - fourth intercostal space at the right
sternal border
v6 - left midaxillary line at the v4 level (fifth intercostal space midclavicular
line)
primary dysrhythmia monitoring lead - ANSWER- V1
what is lead II used for? - ANSWER- used to identify atrial activity if unclear
in other leads or for visualization of R waves during synchronized
cardioversion
rhythms with a short PR interval - ANSWER- may indicate presence of
accessory pathway
lead III or avF - ANSWER- assists in diagnosis of hemiblock
allows identification of retrograde P waves
allows identification of atrial flutter waves
QUESTIONS AND CORRECT ANSWERS
atrial fibrillation adverse consequences - ANSWER- 1. decreased cardiac
output due to loss of atrial kick, rapid ventricular rate, irregular ventricular
rhythm
2. tachycardia induced cardiomyopathy - in rapid afib for prolonged period
of time
3. thromboembolism
right bundle branch - ANSWER- -right side of the interventricular septum
and right ventricle
-impulse travels slower as the right ventricle is smaller/thinner
left bundle branch - ANSWER- two main divisions: anterior fascicle and
posterior fascicle carrying impulses to the left ventricle
PR interval - ANSWER- delay of AV node to allow filling of ventricles
,QRS complex - ANSWER- ventricular depolarization
shape depends on the lead that is being monitored and the ventricular
activation device
T wave - ANSWER- ventricular repolarization
normally in the same direction as the QRS
upright, flat, inverted
pathologies of T wave - ANSWER- MI, E/L levels, drug effect, myocardial
disease, and lead being recorded
u wave - ANSWER- repolarization of the purkinje fibers
SHOULD BE POSITIVE especially when T wave is positive
large u waves can be seen when repolarization is abnormally prolonged -
E/L imbalances like hypokalemia, hypocalcemia, hypomagnesemia, IICP,
LVH, certain medications
ST segment - ANSWER- early ventricular repolarization
should be at isoelectric line
,J point - ANSWER- where QRS complex ends and ST segment begins
QT interval - ANSWER- ventricular depolarization and repolarization varies
with age, gender, and heart rate
beginning of the QRS to the end of the T wave
QT must be corrected to a HR of 60 bpm
QTc - ANSWER- corrected QT interval =
QT/(square root of R-R interval)
normalizes for HR
long QTc --> torsades, ventricular arrhythmia, Vfib
vertical axis - ANSWER- each small box is 1mm or 0.1 mV
each large box is 5mm or 0.5 mV
most common complication of ischemic heart disease and MI - ANSWER-
dysrhythmias
best leads for differentiating wide QRS rhythms - ANSWER- v1 and v6
v1 and v6 - ANSWER- helps to differentiate VTACH from SVT with
aberrant intraventricular conduction
, helps to recognize right and left bundle branch blocks
differentiates between right and left ventricular ectopy
differentiates between right and left ventricular pacing
v1 and v6 placement - ANSWER- v1 - fourth intercostal space at the right
sternal border
v6 - left midaxillary line at the v4 level (fifth intercostal space midclavicular
line)
primary dysrhythmia monitoring lead - ANSWER- V1
what is lead II used for? - ANSWER- used to identify atrial activity if unclear
in other leads or for visualization of R waves during synchronized
cardioversion
rhythms with a short PR interval - ANSWER- may indicate presence of
accessory pathway
lead III or avF - ANSWER- assists in diagnosis of hemiblock
allows identification of retrograde P waves
allows identification of atrial flutter waves
