Arrhythmias Flashcards Preview

Fall 2014 - Pharm Cardio > Arrhythmias > Flashcards

Flashcards in Arrhythmias Deck (47):
1

What sxs might be associated with a-fib?

-palpitations, SOB, dyspnea, dizziness, fatigue

2

What are the 3 goals in management of a-fib?

1. control rate
2. prevent thromboembolism
3. correct to normal sinus rhythm, maintain

3

What is the goal of pharm therapy to control the ventricular rate in a-fib?

-slow the conduction velocity
-increase refractory period at AV node

4

What drugs can be used to control ventricular rate in a-fib?

-beta blockers
-non-dihydropyridine calcium channel blockers
-digoxin and amiodarone are alternative choices

5

MOA of Non-Dihydropyridines in A-fib Rate Control

-work at AV node to decrease conduction velocity and increase refractory period
-slows down the ventricular rate

6

What CCB are used for a-fib rate control?

-non-dihydropyridines: diltiazem and verapamil

7

What must be monitored when using CCB for a-fib rate control?

-BP because diltiazem and verapamil are vasodilators
-signs of CHF due to negative inotropic effect

8

MOA of Beta Blockers in A-fib Rate Control

-block beta adrenergic receptors in heart
-decreased conduction at AV node and increased refractory period

9

What oral BBs are commonly used in a-fib rate control?

-atenolol
-metoprolol

10

What must be monitored when using BB for a-fib rate control?

-BP for HoTN
-bradycardia
-exacerbation of CHF

11

Adverse Effects of BBs in A-fib Rate Control

-CNS: fatigue, lethargy, depression, sexual dysfunction

12

MOA of Digoxin in A-fib Rate Control

-increases vagal tone to slow conduction at AV node

13

It is advantageous to use digoxin in 2 circumstances for a-fib control. What are they?

-pt HoTN: other agents reduce BP, dig has no effect on BP
-advantage in CHF exacerbation: other agents may decrease heart's contractility

14

What must be monitored when using digoxin in a-fib rate control?

-HR, BP, electrolytes (for hypokalemia/magnesemia)
-rhythm for any new arrhythmias
-signs of toxicity: hallucinations, N/V, AV block
-serum level

15

MOA of Amiodarone in A-Fib Rate Control

-beta blocker and CCB to slow down heart rate
-also has anti-arrhythmic actions to convert a-fib

16

When is anticoagulation needed when converting a-fib to NSR?

-if a-fib 48 hours or unknown, anticoag is needed: 3 weeks of warfarin before cardioversion

17

What are some of the agents that can be used to convert a-fib to NSR?

-procainamide, quinindine
-propafenon, flecanide
-amiodarone
-ibutilide, dofetilide, sotalol

18

MOA of Procainamide/Quinindine/Disopyramide

-inhibit fast sodium channels
-decreases conduction velocity
-increases refractory time
-decreases automaticity

19

In what patients do propafenone and flecanide need to be avoided?

-pt with with structural heart dz like CAD or CHF

20

MOA of Amiodarone

-provides rate control
-may convert to NSR and maintain NSR once converted

21

What are some downsides of amiodarone use?

-potentially serious long term risk of pulmonary fibrosis
-hypo or hyperthyroidism
-hepatic dysfunction
-skin discoloration
-ocular toxicities

22

What must be monitored short term with amiodarone?

-bradycardia
-heart block
-HoTN
-drug interactions w/ warfarin, digoxin, statins
-GI disturbances

23

What must be monitored long term with amiodarone?

-PFT and CXR at baseline then annual CXR
-LFTs at baseline and q6 months
-thyroid function test at baseline and 2-3x/yr thereafter

24

How is ibutilide used?

-one time IV dose to convert to NSR

25

What are some problems associated with ibutilide/dofetilide use?

-can cause QT prolongation, proarrhythmias, torsades de pointes

26

What is important to remember about dofetilide dosing?

-adjust for renal function (lower doses for poorer CrCl)

27

What is sotalol indicated for?

-BB with additional anti-arrhythmic properties
-indicated for maintaining NSR once converted

28

What must happen with paroxysmal supraventricular tachycardia in order to convert to NSR?

-must break the re-entry pathway in the AV node

29

How is PSVT treated and what is the DOC?

-initially, carotid sinus massage
-use drugs to slow AV nodal conduction
-adenosine is DOC, but verapamil, diltiazem and BBs also work

30

MOA of Adenosine

-briefly interrupts conduction at AV node to break re-entry

31

What must be monitored with adenosine use?

-peripheral vasodilation: HoTN, flushing, SOB, chest tightness, apprehension

32

When is adenosine contraindicated?

-in heart transplant patients

33

What is primary prevention of ventricular arrhythmias?

-at elevated risk of ventricular arrhythmias, but have never experienced an episode

34

What is secondary prevention of ventricular arrhythmias?

-have survived or experienced v-tach w/o a precipitating cause or experience syncope thought to be caused by tachyarryhthmias

35

How is stable v-tach (non-cardiac arrest) treated?

-with amiodarone

36

How is unstable v-tach (non-cardiac arrest) treated?

-with cardioversion

37

Besides amiodarone, what other drugs can be used for v-tach (non-cardiac arrest)?

-lidocaine
-procainamide

38

How is torsades de pointes with a prolonged QT interval corrected?

-correct electrolytes
-give magnesium

39

What are the various ventricular arrhythmias?

-v-fib
-v-tach
-asystole
-pulseless electrical activity (PEA)

40

During v-fib/v-tach, asystole or PEA, what drugs can improve perfusion?

-epinephrine or vasopressin

41

During v-fib/v-tach, what drugs can "fix" the rhythm?

-amiodarone
-lidocaine
-procainamide

42

During asystole or PEA, what drugs can "fix" the rhythm?

-atropine possibly

43

MOA of Epinephrine

-improves perfusion to heart and brain during CPR
-peripheral vasoconstriction = increased cardiac conduction and improved cardiac contractility

44

MOA of Vasopressin

-improves perfusion to heart and brain during CPR
-alternative to epi
-increase coronary perfusion pressure, vital organ blood flow, cerebral blood flow

45

Indications for Mag Sulfate

-torsades de pointes
-suspected hypomagnesemic state
-refractory ventricular arrhythmias
-digoxin toxicity

46

MOA of Atropine

-anticholinergic effects --> increased SA node firing and AV node conduction

47

How much epi is given to a patient in cardiac arrest?

1 mg IV q3-5 minutes