3/2/25, 3:34 PM Basic Dysrhythmias & EKG Interpretation Comprehensive Question and Answer Session with a Perfect 100% Accuracy, 2025 Flashc…
Basic Dysrhythmias & EKG Interpretation
Comprehensive Question and Answer Session
with a Perfect 100% Accuracy, 2025
Save
Terms in this set (24)
NSR
Rate: 60-100 bpm
Regularity: Regular
Normal Sinus Rhythm P Waves: Normal
PR Interval: 0.12-0.20 s
QRS Duration: 0.04-0.12 s
QT Duration: 0.36-0.44 s
Sinus Node Problems:
The SA node can:
Sinus Node
--Fire too slow (Sinus Bradycardia [SB])
--Fire too fast (Sinus Tachycardia [ST])
Rate <60 bpm
Etiology--SA node is depolarizing slower than normal,
impulse is conducted normally
Sinus Bradycardia (SB) --Normal PR interval and QRS interval
--Once SA node fires, everything else happens
normal
Can be normal for super athletes
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, 3/2/25, 3:34 PM Basic Dysrhythmias & EKG Interpretation Comprehensive Question and Answer Session with a Perfect 100% Accuracy, 2025 Flashc…
May be appropriate response to stress
Rate >100 bpm
Etiology--SA node is depolarizing faster than normal,
Sinus Tachycardia (ST)
impulse is conducted normally
Remember: it is a response to physical or
psychological stress, not primary arrhythmia
Atrial Arrhythmias
Atrial cells can:
--Fire occasionally from a focus (Premature Atrial
Contractions [PACS])
Atrial cells --Fire continuously due to a looping re-entrant circuit
(Atrial Flutter)
--Fire continuously from multiple foci OR fire
continously due to multiple micro re-entrant
"wavelets" (Atrial Fibrillation)
These ectopic cells origionate in the atria (but not the
SA node), therefore the contour of the P wave, the PR
interval, and the timing are DIFFERENT than normally
Premature Atrial generated pulse from the SA node
Contractions (PACs) Etiology--Excitation of an atrial cell forms an impulse
that is then conducted normally through the AV node
and the ventricles
--One cell randomly firing (anywhere in atria)
No P waves. Instead, flutter waves ("sawtooth
pattern") are formed at a rate of 250-300 bpm
Only some impulses conduct through the AV node
(usually every other impulse)
Atrial Flutter (A Flutter)
Etiology--every 2nd, 3rd, or 4th impulse generating a
QRS
--Others are blocked in the AV node as the node
repolarizes
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Basic Dysrhythmias & EKG Interpretation
Comprehensive Question and Answer Session
with a Perfect 100% Accuracy, 2025
Save
Terms in this set (24)
NSR
Rate: 60-100 bpm
Regularity: Regular
Normal Sinus Rhythm P Waves: Normal
PR Interval: 0.12-0.20 s
QRS Duration: 0.04-0.12 s
QT Duration: 0.36-0.44 s
Sinus Node Problems:
The SA node can:
Sinus Node
--Fire too slow (Sinus Bradycardia [SB])
--Fire too fast (Sinus Tachycardia [ST])
Rate <60 bpm
Etiology--SA node is depolarizing slower than normal,
impulse is conducted normally
Sinus Bradycardia (SB) --Normal PR interval and QRS interval
--Once SA node fires, everything else happens
normal
Can be normal for super athletes
https://quizlet.com/1012700254/basic-dysrhythmias-ekg-interpretation-comprehensive-question-and-answer-session-with-a-perfect-100-accuracy-2025… 1/6
, 3/2/25, 3:34 PM Basic Dysrhythmias & EKG Interpretation Comprehensive Question and Answer Session with a Perfect 100% Accuracy, 2025 Flashc…
May be appropriate response to stress
Rate >100 bpm
Etiology--SA node is depolarizing faster than normal,
Sinus Tachycardia (ST)
impulse is conducted normally
Remember: it is a response to physical or
psychological stress, not primary arrhythmia
Atrial Arrhythmias
Atrial cells can:
--Fire occasionally from a focus (Premature Atrial
Contractions [PACS])
Atrial cells --Fire continuously due to a looping re-entrant circuit
(Atrial Flutter)
--Fire continuously from multiple foci OR fire
continously due to multiple micro re-entrant
"wavelets" (Atrial Fibrillation)
These ectopic cells origionate in the atria (but not the
SA node), therefore the contour of the P wave, the PR
interval, and the timing are DIFFERENT than normally
Premature Atrial generated pulse from the SA node
Contractions (PACs) Etiology--Excitation of an atrial cell forms an impulse
that is then conducted normally through the AV node
and the ventricles
--One cell randomly firing (anywhere in atria)
No P waves. Instead, flutter waves ("sawtooth
pattern") are formed at a rate of 250-300 bpm
Only some impulses conduct through the AV node
(usually every other impulse)
Atrial Flutter (A Flutter)
Etiology--every 2nd, 3rd, or 4th impulse generating a
QRS
--Others are blocked in the AV node as the node
repolarizes
https://quizlet.com/1012700254/basic-dysrhythmias-ekg-interpretation-comprehensive-question-and-answer-session-with-a-perfect-100-accuracy-2025… 2/6
