Week 7a: Cardiac Arrhythmias

Question 1

P waves in sinus arrythmias

Answer 1

P waves are upright in I, II and aVF

Question 2

Treatment for sinus bradycardia?

Answer 2

atropine 0.5mg q3-5min or adrenergic infusions such as dopamine or epinephrine IV

Question 3

causes of sinus tachycardia

Answer 3

exercise, fever, and hyperthyroidism among others

Question 4

treatment of sinus tachycardia

Answer 4

digoxin, beta blockers, CCBs, BBs, amiodarone

Question 5

paroxysmal supra ventricular tachycardia

Answer 5

episodes of rapid heart rate that start in a part of the heart above the ventricles

Question 6

what is the most common arrhythmia?

Answer 6

atrial fibrillation

Question 7

chaotic and ineffective atrial depolarization

Answer 7

atrial fibrillation

Question 8

signs and symptoms of atrial fibrillation

Answer 8

fainting, exercise intolerance, palpitations, pulmonary edema, decreased CO

Question 9

medications for atrial fibrillation

Answer 9

• anticoagulants
• CCBs
• BBs
• cardiac glycosides

Question 10

what is an intervention for atrial fibrillation?

Answer 10

atrial ablation

Question 11

ECG of atrial fibrillation

Answer 11

• tracing shows irregularly irregular rhythm with no P waves

Question 12

which arrhythmia has the following characteristics?

• regular ventricular rate of 150bpm
• varying ratios of F waves to QRS complexes (most common is 4:1)
• Sawtooth pattern

Answer 12

atrial flutter

Question 13

which ECG will show a constant PR interval, greater than 2 seconds and all impulses conducted?

Answer 13

1st Degree AV block

Question 14

Which arrhythmia results when each impulse is slower and slower and finally does not conduct an impulse, which results in a PR interval that gets longer and longer until a QRS complex is missing

Answer 14

2nd degree AV block type 1

Question 15

Which arrhythmia has the following characteristics?

• AV node conducts no impulses
• atria and ventricles beat at an intrinsic rate (80 and 40 respectively)
• no association between P waves and QRS complexes

Answer 15

3rd degree AV block

Question 16

What are some characteristics of ventricular arrhythmias?

Answer 16

• wide QRS complex
• Variable rate
• No P waves

Question 17

what arrhythmia occurs earlier than the sinus beat, is wide and has no P wave?

Answer 17

Premature ventricular contraction

Question 18

idioventricular rhythm

Answer 18

• escape rhythm

- 20-40 bpm

Question 19

which ventricular arrhythmia has a rate greater than 100 bpm

Answer 19

ventricular tachycardia

Question 20

which type of ventricular tachycardia occurs secondary to prolonged QT interval?

Answer 20

Torsades des pointes

Question 21

what type of ventricular arrhythmia includes unorganized activity of the ventricle?

Answer 21

ventricular tachycardia/fibrillation

Question 22

which type of arrhythmia is life threatening, pulseless, with no CO?

Answer 22

Vfib and Vtach

Question 23

vtach/vfib algorithm

Answer 23

1) CPR/IV/Access airway
2) Defibrillate 360 J
3) Epinephrine 1mg q3-5min
4) Amiodarone 300mg bolus

Question 24

asystole algorithm

Answer 24

1) CPR/IV/Airway
2) Epinephrine 1mg q3-5min
3) consider pacing (low effectiveness)

Question 25

class I drugs

Answer 25

act by blocking the fast sodium channels

Question 26

class II agents

Answer 26

beta adrenergic blocking drugs that act by blunting the effect of sympathetic nervous system stimulation on the heart

Question 27

class III agents

Answer 27

act by extending the action potential and refractoriness

Question 28

class IV agents

Answer 28

act by blocking the slow calcium channels, thereby depressing phase 4 and lengthening phase 1 and 2

Question 29

procainamide is a?

Answer 29

sodium channel blocker

Question 30

therapeutic effects and uses for procainamide?

Answer 30

PAT, atrial flutter, atria fibrillation and prophylaxis of PSVT

Question 31

adverse effects of procainamide?

Answer 31

confusion and psychosis at high doses

Question 32

what is the primary indication of class IB drugs?

Answer 32

ventricular dysrhythmias

Question 33

class IB drugs work by?

Answer 33

shortening the refractory period

Question 34

Lidocaine is a?

Answer 34

Class IB drug

Question 35

class IC drugs....?

Answer 35

profoundly decrease conduction velocity

Question 36

what is the prototype drug of beta blockers?

Answer 36

propranolol

Question 37

beta blockers work by?

Answer 37

decreasing the conduction velocity

Question 38

what is the prototype drug of potassium channel blockers?

Answer 38

amiodarone

Question 39

therapeutic effects and uses of amiodarone?

Answer 39

- atrial and ventricular dysrhythmias - resistant ventricular tachycardias - recurrent fibrillation

Question 40

what are some serious adverse effects of amiodarone?

Answer 40

- pneumonia like syndrome | - prodysrhythmic action (arythmias)

Question 41

what is the prototype drug of calcium channel blockers?

Answer 41

verapamil

Question 42

which medication is contraindicated in ventricular dysthymias and must be carefully monitored for toxicity, drug interactions, and adverse effects

Answer 42

digoxin

Question 43

diastolic heart failure

Answer 43

signs and symptoms of heart failure with normal ejection fraction. mainly seen in elderly patients with hypertensive heart disease

Question 44

what results due to low cardiac output?

Answer 44

hypotension

Question 45

which condition includes peripheral edema, weight gain, liver congestion dysfunction and failure, renal hypertension, abdominal distension, LOC changes, and fatigue

Answer 45

right sided heart failure

Question 46

causes of right sided heart failure

Answer 46

- conditions that restrict blood flow to the lungs - stenosis or regurgitation of the tricuspid or pulmonic valves - right ventricular infarction - cardiomyopathy - persistent life sided failure - acute or chronic pulmonary disease (for pulmonale)

Question 47

causes of left sided heart failure?

Answer 47

- acute MI | - cardiomyopathy

Question 48

manifestations of left sided heart failure

Answer 48

- SOB - crackles - pulmonary edema - exercise intolerance - cough and pink froth (rare)

Question 49

what is the result of fluid moving into the alveoli, causing lung stiffness, making lung expansion more difficult and impairs the gas exchange function of the lung

Answer 49

pulmonary edema

Question 50

How do ACEIs help in HF?

Answer 50

- decrease vascular resistance - decrease secretion of aldosterone - decrease secretion of ADH

Question 51

what are some serious adverse effects of ACEIs?

Answer 51

Angioedema, cough, and hyperkalemia

Question 52

dobutamine and dopamine are examples of?

Answer 52

beta 1 adrenergic agonists

Question 53

what do beta1 adrenergic agonists do?

Answer 53

increase contractility of the heart to produce more powerful contractions but also reduce vasoconstriction and can produce dysrhythmias including tachycardia

Question 54

the effect of increased force of contraction of the heart when digoxin is a result of?

Answer 54

increased calcium in the cell

Question 55

what are some serious adverse effects of digoxin?

Answer 55

atrial dysrhythmias, sinus bradycardia, ventricular dysrhythmias, AV block

Question 56

what is often the first sign of digoxin toxicity?

Answer 56

nausea and vomiting

Question 57

what is the PO onset of digitalization?

Answer 57

30-120 mins

Question 58

What is the peak of PO digitalization?

Answer 58

2-6 hours

Question 59

how many days of digitalization until steady state is achieved?

Answer 59

7 days

Question 60

IV onset of digitalization?

Answer 60

5- 30 mins

Question 61

peak of IV digitalization

Answer 61

1-4 hours

Question 62

therapeutic level of digoxin?

Answer 62

0.8-2ng/ml

Question 63

toxic level of digoxin

Answer 63

>2.4 ng/ml

Question 64

contraindications of digoxin

Answer 64

- patients taking calcium channel blockers | - ventricular fibrillation

Question 65

Milrinone is a?

Answer 65

phosphodiesterase III inhibitor

Question 66

therapeutic effects and uses of milrinone (primacor)?

Answer 66

Short term treatment of life threatening heart failure

Question 67

mechanism of action of milrinone (primacor)

Answer 67

the persistence of cGMP results in vasodilation and a positive inotropic effect

Question 68

adverse effects of milrinone (primacor)

Answer 68

headache, nausea, vomiting, ventricular dysrhythmias