Atrial Dysrhythmias

Question 1

Name the 4 types of Atrial Dysrhythmias

Answer 1

Premature Atrial Contraction (PAC)
Atrial Fibrillation
Atrial flutter
Paroxysmal supraventricular tachycardia (PSVT)

Question 2

Define Premature Atrial Contractions

Answer 2

Ectopic pacemaker in atrium discharges before SA node fires

Question 3

What causes Premature Atrial Contractions?

Answer 3

Usually, benign
Check electrolytes (If you notice new onset of PAC’s/ increased in frequency check for electrolyte imbalance)
Increase in frequency may be indicated patient is about to convert to a-fib
Stress
Cardiac stimulants (caffeine)
May indicate Atrial pathology

Question 4

Define Atrial Fibrillation

Answer 4

Total disorganization of serial electrical activity due to multiple ectopic foci,resulting in loss of effective Atrial Contraction (kick)

Atrial rate >400bpm Ventricular rate >100-175bpm

R to R intervals are Irregularly Irregular

Most common dysrhythmia

Prevalence increases with age

Question 5

What causes Atrial Fibrillation?

Answer 5

Usually occurs with some underlying heart disease (all of them)
Electrolyte imbalance
Hypoxia
Cardiac surgery

Question 6

Atrial Fibrillation equation

Answer 6

Atrial Fibrillation=fibrillating atria=pooling of blood=clot information=risk for embolus

Note: If in LA (left atria) can cause a stroke

Question 7

What will the patient with Atrial Fibrillation look like?

Answer 7

Depends on Ventricular rate, how long rhythm has been present, and the patient’s CV status.

Typically, Onset is FAST rate-so s/s are those of tachydysrhythmia

Question 8

Define Atrial flutter

Answer 8

Identified by recurring, regular, saw-toothed-shaped flutter waves

Originates from a single ectopic focus; reentry impulse is repetitive & cyclic (one irritable cardiac cell in the atria that wants to be in charge)

R to R interval is regular or irregular

Atrial rate may be >250bpm; Ventricular rate slower

Question 9

What causes Atrial flutter?

Answer 9

Rarely occurs in a healthy heart; underlying heart condition (any of them)
Electrolyte imbalance

Question 10

What does the patient with atrial flutter look like?

Answer 10

Depends on Ventricular rate, how long the rhythm has been present, and the patient’s CV status

Typically, onset is FAST rate- so s/s are those of tachydysrhythmia

And-Yes at risk for emboli.

Question 11

Atrial Fibrillation/Flutter goals

Answer 11

Ventricular rate control
Rhythm control
Prevent embolic stroke

Question 12

How do we treat Atrial Fibrillation/Flutter?

Answer 12

Drugs for RATE control: B-adrenergic Blockers(metoprolol),calcium channel Blockers(diltiazem, verapamil)-initially IV route

Drugs for RHYTHM control: amiodarone & doFETilide-initially IV route

Drugs to prevent clots: warfarin

Question 13

How do we treat Atrial Fibrillation/Flutter?

Answer 13

If stable, but symptomatic?
Slow Ventricular rate with IV either calcium channel blocker, beta blocker, digitalis, amiodarone

May be “bolus” & start a drip…

If unstable/hemodynamically compromised?
Synchronized cardioversion

Question 14

Define Synchronized cardioversion

Answer 14

Choice of therapy for hemodynamically unstable supraventricular tachydysrhythmia

Synchronized circuit delivers a countershock on the R wave of the QRS complex of the ECG (need to have a R wave before cardioverting a patient)

Synchronizer switch must be turned ON

Question 15

If the synchronized cardioversion is non-emergency the patient is sedated before the procedure (True/False)

Answer 15

True

Question 16

What is the initial energy for synchronized cardioversion?

Answer 16

50 to 100 Joules (increase if needed)

Question 17

Make sure all personnel are “ALL CLEAR” before discharging the device during a synchronized cardioversion (True or False)

Answer 17

True

Question 18

What do you do if a patient becomes pulseless during a synchronized cardioversion?

Answer 18

Turn the synchronizer switch OFF & perform defibrillation

Question 19

Synchronized cardioversion nursing care

Answer 19

Maintain patent airway
Administer oxygen
Assess VS & LOC
Monitor for dysrhythmias
Provide emotional support
Document results of cardioversion

Question 20

How to treat Atrial Fibrillation if has a-fib for >48 hours

Answer 20

Anticoagulation therapy with warfarin (Coumadin) is recommended for 3 to 4 weeks before cardioversion and 3 to 4 weeks after successful cardioversion

Question 21

What procedure is performed before a Cardioversion (to make sure no clots in atrium)

Answer 21

TEE (Transesophageal Echocardiogram)

Question 22

What medication will be administered if emergent cardioversion performed?

Answer 22

Low-molecular weight heparin or heparin drip will be initiated.

Question 23

If treatment for atrial Fibrillation/Flutter doesn’t work, what’s next?

Answer 23

Long term anticoagulation therapy.
Drug of choice is typically warfarin (Coumadin)
Disadvantage-have to monitor INR regularly

Alternative anti-coag drugs
dabigatran (Pradaxa), apixaban (eliquis) Twice daily
Rivaroxaban (Xarelto), eboxaban (Savaysa) once daily
Advantage: (no routine lab testing)
Disadvantage: Cost, more than once daily dosing & contraindicated with impaired renal function

Question 24

What limits atrial Fibrillation/Flutter pharmacy therapy for dysrhythmias?

Answer 24

High failure rates
Potential for drug toxicity

Question 25

Non-pharmacology treatment for atrial Fibrillation/flutter.

Answer 25

Catheter ablation
Radio-frequency or cryothermal therapy

Maze procedure

Question 26

What is a Catheter ablation?

Answer 26

Invasive procedure that destroys an irritable focus causing the dysrhythmia

Must undergo EP studies & mapping procedures to locate the focus.

Question 27

What is a Maze procedure?

Answer 27

Surgical procedure consists of creating a number of incisions in atrium to disrupt the re-entrant circuits. Looks schematically like a children’s Maze with only one path from the SA node to the AV node.

Question 28

Define Paroxymal Supraventricular tachycardia (PSVT)

Answer 28

Originates in ectopic focus anywhere above bifurcation of Bundle of His

Run repeated premature beats is initiated and it usually starts with a PAC

Paroxysmal refers to an abrupt onset and termination (without warning).

Question 29

What causes PSVT?

Answer 29

In normal heart
Overexertion
Emotional stress
Stimulants

Digitalis toxicity
Various forms of heart disease

Question 30

What does the patient look like with PSVT?

Answer 30

Depends on how long it lasts & how FAST Ventricular rate

(See Key Features slide) Tachydysrhythmias

Question 31

How do we treat PSVT?

Answer 31

Vagal maneuvers (should be on monitor)
Valsalva (most effective)- Hold breath 10-15 seconds (should see neck distention), then resume breathing.
Coughing
Carotid sinus massage (CSM) MD ONLY
Diving reflex/cold water immersion- submerge face in cold water (triggers vagal response)-Due to complexities, rarely used in modern clinical medicine

Question 32

How to treat PSVT if vagal maneuvers fail?

Answer 32

Adenosine IV push
VERY short half life (follow with rapid NS flush)
May cause a pause on rhythm strip, patient may be aware

Onset=10-40 seconds/duration 1-2 minutes

Question 33

How do we treat PSVT if vagal maneuvers and/or drug therapy is ineffective and/or patient becomes hemodynamically unstable?

Answer 33

Cardioversion