Junctional rhythms

Question 1

junctional rhythms

Answer 1

Dysrhythmias Sustained or Originating in the AV Junction

Question 2

dysrhythmias

Answer 2

– Premature Junctional Contractions
– Junctional Escape Complexes and Rhythms
– Accelerated Junctional Rhythm
– Paroxysmal Junctional Tachycardia
-Inverted, Buried, or Retrograde P Waves in Lead II
– PRI of <0.12 Seconds
– Normal QRS Complex Duration

Question 3

junctional complexes

Answer 3

• can be:
• inverted in front of the QRS (p wave) -> depolarizes atria from the bottom up bc it comes from the AV node
• buried within the QRS
• inverted behind the QRS
• timing is can different bc there is no delay between contractions when impulses come from the AV node

Question 4

premature junctional contractions (PJC)

Answer 4

• rate depends on underlying rhythm
• rhythm depends on underlying rhythm
• pacemaker site is the ectopic focus in the AV junction
• P waves- inverted, may occur after the QRS
• PRI- normal if P occurs before QRS
• QRS is usually normal
• p wave can be absent in one complex

Question 5

premature junctional contractions: etiology, clinical sig, treatment

Answer 5

• etiology- single electrical impulse originating in the AV node
• may occur with us of caffeine, tobacco, alcohol, sympathomimetic drugs, ischemic heart disease, hypoxia, or digitalis toxicity, or may be idiopathic.
• Clinical Significance- Limited, frequent PJCs may be precursor to other junctional dysrhythmias.
• Treatment- None usually required.

Question 6

junctional escape complexes and rhythms

Answer 6

• rate- 40-60
• rhythm- irregular in single occurrence, regular in escape rhythm
• pacemaker site- AV junction
• p waves- inverted, may occur after QRS
• PRI- normal if p occurs before QRS
• QRS usually normal

Question 7

junctional escape complexes and rhythms: etiology, clinical significance, treatment

Answer 7

• Etiology- Results when the AV node becomes the pacemaker.
• Results from increased vagal tone, pathologically slow SA discharges, or heart block.
• Clinical Significance- Slow rate may decrease cardiac output, precipitating angina and other problems.
• Treatment- None if the patient remains asymptomatic.
• treat symptomatic episodes with atropine or pacing as indicated

Question 8

difference between premature and junctional escape complexes

Answer 8

• only the beat

- for premature the beat is happening early

Question 9

accelerated junctional rhythm

Answer 9

• rate- 60-100
• rhythm- regular
• pacemaker site- AV junction
• p waves- inverted, may occur after QRS, buried
• PRI- normal is p wave is before QRS
• QRS normal

Question 10

accelerated junctional rhythm: etiology, clinical sig, treatment

Answer 10

• Etiology- Results from increased automaticity in the AV junction.
• Often occurs due to ischemia of the AV junction.
• Clinical Significance- Usually well tolerated, but monitor for other dysrhythmias.
• treatment- None generally required in the prehospital setting

Question 11

junctional tachycardia

Answer 11

• rate- > 100-180
• rhythm- regular
• pacemaker site- AV junctions
• p waves, inverted, may occur after QRS, buried
• PRI- normal if p waves occurs before QRS
• QRS- normal

Question 12

junctional tachycardia: etiology, clinical sig, treatment

Answer 12

• Etiology- Rapid AV junction depolarization overrides the SA node.
• Occurs with or without heart disease.
• May be precipitated by stress, overexertion, smoking, or caffeine ingestion.
• Clinical Significance- May be well tolerated for brief periods.
• Decreased cardiac output will result from prolonged episodes, which may precipitate angina, hypotension, or congestive heart failure

Question 13

> 100

Answer 13

junctional tachycardia