Atrial Dysrhythmias?

Question 1

What causes an Atrial dysrhythmia?

Answer 1

Ectopic impulses in either the right or left atrium or both

Question 2

What is an Ectopic Impulse

Answer 2

electrical impulse that comes from outside the normal pacemaker site or electrical conduction pathway

Question 3

Premature Atrial Complex (PAC)

Answer 3

result of early electrical impulses, originate in atria interrupting the inherent regular rhythm

Question 4

PAC Rhythm Criteria

Answer 4

Rhythm: P & R intervals are constant with exception of early complexes; irregular rhythm
Rate: Atria & ventricles usually within normal limits 60-100bpm
P wave morph: P wave with normal complexes, have same shape (upright uniform); P wave with early complexes have a different shape (flattened, notched, biphasic or epuiphasic) or hidden in T wave
PRI: measures within normal limits of 0.12-0.20 seconds; early complexes may have different measurements but still within normal limits
QRS duration and morph: within normal limits, 0.06-0.10 seconds

Question 5

PAC’s effect on cardiac output?

Answer 5

• Usually benign condition
• Patient may exhibit signs and symptoms of low cardiac output (table 5-2 in textbook pg 138)
• complain of palpitations

Question 6

Wandering Atrial Pacemaker (WAP)

Answer 6

• pacemaker site shifts between SA node, other sites in atria and/or AV junction
• at least three different P wave morphologies in same lead

Question 7

WAP Rhythm Criteria

Answer 7

Rhythm: slightly irregular
Rate: should be within normal limits 60-100bpm
P wave morphology: continuous change in appearance with at least 3 different shaped P waves
PRI: varies
QRS duration and morp: within normal limits 0.06-0.10 seconds

Question 8

WAP effect on patients

Answer 8

• normal finding in children, older adults and well-conditioned athletes
  may be related to some types of organic heart disease and drug toxicity

Question 9

Multifocal Atrial Tachycardia
(MAT)

Answer 9

P wave that changes from beat to beat and a heart rate of 101-150bpm
***same characteristics as WAP but has a heart rate excess of 100bpm

Question 10

MAT Rhythm Criteria

Answer 10

Rhythm: irregular
Rate: between 101-150bpm
P wave morph: P wave changes in appearance from beat to beat; may be upright, rounded, notched, inverted, biphasic, or buried in QRS complex
PRI: varies due to changing origin of electrical activity
QRS duration and morph: within normal limits 0.06-0.10 seconds and all complexes look alike

Question 11

What triggers MAT?

Answer 11

acute exacerbation of emphysema, congestive heart failure (CHF), or acute mitral valve regurgitation

Question 12

Atrial Flutter (A-Flutter)

Answer 12

rapid impulse originates in the atrial tissue; ectopic focus maybe originating from ischemic areas of the heart with enhanced automaticity or reentry pathway***

Question 13

What is a Reentry Pathway

Answer 13

is an extra electrical pathway that has developed in which a group of cells are generating an impulse faster then the SA node

looks for quickest pathway to AV**

Question 14

What is a Flutter Wave

Answer 14

electrical current or rhythm that has characteristic sawtooth or picket fence pattern

Question 15

Atrial Flutter Rhythm Criteria

Answer 15

Rhythm: Atrial flutter to flutter is regular interval; R wave interval, usually regular can be irregular
Rate: Atrial rate is between 250-350bpm
** if regular rhythm, use 1500 method for ventricular rate and for atrial is # of flutters between R-R interval multiplied by the ventricular rate (V=100 x A=3 gives you 300bpm)
P wave morph: P wave not seen only flutters; more flutters then QRS now
PRI: not identifiable since P waves doesn’t exist
QRS duration and morph: within normal limits 0.06-0.10seconds

Question 16

Atrial Flutter effects on Cardiac Output

Answer 16

loss of atrial kick** and patient will demonstrate low cardia output signs and symptoms

**atrial kick: the extra blood that can be ejected into the ventricles by the atria as a result of the electrical impulse slowing as it enters the AV node

Question 17

Atrial Fibrillation (A-fib)

Answer 17

when electrical impulses come from areas of reentry pathways or multiply ectopic foci (abnormal cells causing multiple electrical impulses); each impulse results in depolarization of only a small group of atrial calls instead of the whole atrium

Question 18

Atrial Fibrillation Rhythm Criteria

Answer 18

Rhythm: P-P intervals cant be determined because of F waves; and R-R is irregular
Rate: Atrial rate cannot be determined; use 6 second method to calculate ventricle rate
P wave morph: P waves are not present; electrical chaos is evidence from F waves
PRI: cannot be determined since P wave are not present
QRS duration and morph: within normal limits of 0.06-0.10 seconds and irregular

Question 19

A-Fib effect on Cardiac Output and other vital organs

Answer 19

• exhibits signs and symptoms of decreased cardiac output
• dizziness, nausea, and other signs
  can cause clot (thrombus) to an embolism
• can also have a cerbrovascular accident (CVA), myocardial infarction (MI: heart attack), pulmonary embolism, renal infarction.