Questions &Verified Answers Graded A+
Afib - ANS✔✔--The impulse originates in the Atria
• The Atrial rate is > 300 and unable to measure [N/A]
• No discernable P waves - PRI & Atrial rhythm cannot be measured [N/A]
• The Ventricular rhythm is irregular
• QRS within normal limits
• If the Ventricular rate is <100 the rhythm is controlled A-fib;
if the Ventricular rate is > 100 the rhythm is uncontrolled A-fib
• This is a chronic rhythm for some patients
Treatment: controlled patients: anticoagulants and antiarrythmics; uncontrolled but
stable patients: Beta blockers, calcium channel blockers, or digoxin; Unstable patients:
cardioversion
Bundle Branch Block - ANS✔✔--Impulse travels from SA node to AV node, blocked
at bundle branch level, bypasses
nonworking branch spreads to opposite ventricle via Purkinje fibers causing ventricle
depolarization
• Contraction takes longer leading to wide QRS
• Underlying rhythm must first be identified!
• QRS: Wide; ≥ 0.12
-Treatment: atropine or pacemaker
1st degree Heart Block (1st Degree block, 1st degree HB) - ANS✔✔--The electrical
impulse begins in the SA node then is The electrical impulse begins in the SA node then
is delayed in the AV node longer than normal
due to a partial block and lastly conducts normally through the ventricles.
• Underlying rhythm must first be identified!
• Rhythm: Atrial and Ventricular regular
• Rate: Atrial and Ventricular rates the same
• PRI: Prolonged >0.20, but constant
• QRS: Usually within normal limits
2nd Degree Heart Block Type I (2
and degree Type I) - ANS✔✔--• Impulse starts in the SA node, travels to AV node,
gets delayed at AV node. Progressive delay (partial block,
longer PRI), Impulse does not get release (complete block, dropped QRS)
• Rhythm: Atrial is regular; Ventricular is irregular
• Rate: Atrial rate is greater than ventricular rate
• P waves: Normal in size and shape, but not all followed by QRS
• PRI: Lengthens
• QRS: Usually within normal limits, but is periodically dropped
Junctional Rhythm - ANS✔✔--Impulse starts in the AV junction
, • P waves are absent, short, inverted or retrograde
• Ventricular Rhythm: Regular
• Ventricular Rate: 40-60 bpm
• QRS is usually within normal limits
Accelerated Junctional Rhythm - ANS✔✔--Accelerated Junctional
Same criteria as Junctional Rhythm, except the Ventricular rate is 60-100
For stable patients: IV access, vagal maneuvers, adenosine, O2, Beta blockers, calcium
channel blockers
Idioventricular Rhythm (IVR) - ANS✔✔--Impulse originates in the ventricles
▪ Rhythm: Ventricular is usually regular
▪ Rate: Ventricular between 20-40
▪ QRS: ≥ 0.12
▪ Atrial rate, rhythm, and PRI: N/A
- Treatment: assess pt, check for DNR in chart, transcutaneous pacing, atropine.
NEVER GIVE ANTI-ARRYTHMICS MEDICATIONS
Atrial-ventricular Pacing - ANS✔✔--One pacemaker lead is placed into the right atria
and another is placed into the right
ventricle.
• The pacemaker generator fires an impulse to the atria and then to the ventricle
sequentially
causing atrial then ventricular contraction.
• Rhythm: Atrial and Ventricular regular
• Rate: Atrial and Ventricular same & within set limits
• P waves: Pacer spike seen at beginning of atrial activity P waves may or may not be
seen
(lead type dependent)
• PRI: WNL - Measured from atrial spike to ventricular spike
• QRS: Wide - Measured from ventricular spike to end of QRS
Failure to capture - ANS✔✔--A pacer spike note followed by the appropriate atrial or
ventricular response
• Can be a potentially lethal situation!
Failure to pace - ANS✔✔--Absence of pacer activity (spikes) when the pacemaker
generator should have fired an impulse.
• Typically seen when the patient's intrinsic heart rate falls less than the pacemaker's
low HR limit and
the pacer fails to fire.
normal sinus rhythm (NSR) - ANS✔✔--Impulse starts in the SA Node
• Rate: Atrial & Ventricular 60-100 [WNL]
• Rhythm: Atrial and Ventricular are regular
• P waves: Normal; each followed by QRS