Walraven Cards Flashcards
Name the 8 main parts of the conduction system
SA Node Intraatrial pathway Internodal Pathway AV Junction Bundle of His L. Bundle Branch R. Bundle Branch Purkinje Fibers
What chambers does the sympathetic nervous system affect and how?
Ventricles
Increases Chronotropic, Inotropic, Dromotropic
What chambers does the parasympathetic nervous system affect and how?
Atria
Decreases Chronotropic, Inotropic, Dromotropic
How do you measure PRI? What is normal?
From beginning of the P wave to beginning of QRS complex.
.12-.2 sec (3-5) boxes
How do you measure QRS? What is normal?
From beginning of Q wave to end of S wave.
Less than .12 sec (3 boxes)
What is a P-wave?
Atrial depolarization
Should be before the QRS, can be inverted in a retrograde, after or during the QRS, may be nonexistent, or multiples of
What is the PR segment?
The end of the P wave to the beginning of the QRS. Measures the conduction delay at the AV node.
What is the QRS complex?
Ventricular depolarization
Should be < 3 boxes wide
What is a T wave?
Ventricular repolarization
Should follow a QRS and about 1/2 the amplitude of the QRS
What is the isoelectric line?
When there is either no electrical activity in the heart or when + and - charges are balanced.
How you measure degree of ST elevation or depression
What are the inherent rates for:
- SA Node
- AV Node
- Ventricles
- 60-100
- 40-60
- 20-40
How do you calculate HR when it is irregular, or you just need an estimate?
of R-R waves on a 6 sec strip x 10.
How do you calculate HR when it is regular and you need it to be quick and accurate?
Each large box = 300, 150, 100, 75, 60, 50
or
divide by 300
(less accurate with very fast and very slow rates)
How do you calculate HR when you are most concerned about accuracy?
Count the # of small boxes between R waves and divide by 1500.
Rules for NSR (normal sinus rhythm)
Regularity: Constant RRI and regular
Rate: HR 60-100, atrial rate = ventricular rate
P wave: uniform, 1 P/QRS
PRI: .12-.20 sec or 3-5 boxes, consistent
QRS: <.12 sec or 3 boxes
Rules for Sinus Bradycardia
Regularity: Constant RRI and regular
Rate: HR <.12 sec or 3 boxes
Rules for Sinus Tachycardia
Regularity: Constant RRI and regular
Rate: HR >100<.12 sec or 3 boxes
Rules for Sinus Arrhythmia
Regularity: Variable RRI, may change with respirations
Rate: HR 60-100, atrial rate = ventricular rate
P wave: uniform, 1 P/QRS
PRI: .12-.20 sec or 3-5 boxes, consistent
QRS: <.12 sec or 3 boxes
Rules for Wandering Pacemaker
Regularity: RRI slightly irregular due to changing pacemaker sites
Rate: HR 60-100, atrial rate = ventricular rate
P wave: shape changes as pacemaker site changes, 1 P/QRS but some P may be difficult to see
PRI: .12-.20 sec or 3-5 boxes, slightly variable as pacemaker site changes
QRS: <.12 sec or 3 boxes
Rules for Atrial Flutter
Regularity: Atrial rate is regular, ventricular rate regular only if AV node conducts with a consistent pattern
Rate: HR 250-350, ventricular rate dependent upon ratio of conducted impulses through AV node
P wave: multiple wave with well defined sawtooth appearance
PRI: Undeterminable
QRS: <.12 sec or 3 boxes
Rules for Premature Atrial Complex
Regularity: Single ectopic beat will interrupt regularity of underlying rhythm
Rate: Depends on underlying rhythm
P wave: P-wave of ectopic beat looks different from all others, may be hidden in T wave
PRI: .12-.20 sec or 3-5 boxes, may be prolonged, will likely be different in ectopic beat
QRS: <.12 sec or 3 boxes
Rules for Atrial Tachycardia
Regularity: Constant RRI and regular
Rate: HR 150-250, atrial rate = ventricular rate
P wave: uniform, 1 P/QRS
PRI: .12-.20 sec or 3-5 boxes, consistent
QRS: <.12 sec or 3 boxes
Rules for Atrial Fibrillation
Regularity: Atrial rate is unmeasurable, Ventricular rate is grossly irregular
Rate: Exceeds 350, unmeasurable. “Controlled” ventricular rate 100
P wave: none, grossly chaotic
PRI: Undeterminable
QRS: <.12 sec or 3 boxes
