Antiarrhythmics

Question 1

what is the resting membrane potential of the heart determined by?

Answer 1

high Na concentration outside the cell, maintained by Na-k ATPase pump

Question 2

how is quinidine metabolized?

Answer 2

hepatic metabolism

Question 3

vomiting, tinnitus, HA, blurred vision

Answer 3

cinchonism

Question 4

which class Ia drug would be good to monitor serum levels of to monitor toxicity and efficacy?

Answer 4

procainamide

Question 5

SE:significant anticholinergic effects in addition to being a Na channel blocker

Answer 5

disopyramide

Question 6

which antiarrhytmic is cleared renally (+hepatic)?

Answer 6

disopyramide

Question 7

lidocaine is effective only in _______arryhtmias

Answer 7

ventricular

Question 8

how is lidocaine administered?

Answer 8

IV

Question 9

SE: CNS side effects mostly incl dizziness, paresthesias, confusion, coma, lethargy, tremor, seizures

Answer 9

lidocaine

Question 10

flecainide and propafenone are used for only ______arrhytmias, recommended specifically for patients with _________

Answer 10

atrial

recommended for patients with lone A fib (nothing else)

Question 11

how is flecainide metabolized?

Answer 11

hepatically + renally

Question 12

which 2 class 1 drugs are fairly well tolerated with few side effects?

Answer 12

propafenone and flecainide

Question 13

what have studies shown about ALL class I drugs in patients with CHF?

Answer 13

INCREASED MORTALITY

Question 14

which class of antiarrhytmics have been shown to reduce mortality?

Answer 14

ONLY the beta blockers

Question 15

sotolol is class III drug, as well as a ?

Answer 15

beta blocker (class II)

Question 16

main issue with sotolol?

Answer 16

profound INCREASE IN QT INTERVAL (high risk of Torsades)

Question 17

which class III drug? high bioavailability, hydrophilic, MUST doses down in renal failure

Answer 17

sotolol

Question 18

amiodarone has a low or high Vd?

Answer 18

very high Vd, and LOONNNG half life

Question 19

cardiac abnormalities assc’d with amiodarone

Answer 19

minimal risk of torsades

Question 20

is amiodarone safe or unsafe for heart failure patients

Answer 20

safe for CHF

Question 21

pulmonary abnormalities assc’d with amiodarone

Answer 21

3% get pulmonary fibrosis, delayed hypersensitivity pneumonitis

Question 22

ways to monitor pulmonary risks?

Answer 22

have patient report unexplained dyspnea, cough and fever

Question 23

thyroid abnormalities assc’d with amiodarone

Answer 23

can cause hypo or hyperthyroidism

Question 24

______% of amiodarone is _____

Answer 24

44% of amiodarone is iodine

Question 25

ocular abnormalities assc'd with amiodarone

Answer 25

1. corneal deposits in almost ALL patients | 2. halos, photophobia, overt retinopathy

Question 26

neuro abnormalities assc'd with amiodarone

Answer 26

20-40% patients have tremor, ataxia, peripheral neuropathy

Question 27

derm abnormalities assc'd with amiodarone

Answer 27

photosensitivity,blue green discoloration in sun exposed areas

Question 28

hepatic abnormalities assc'd with amiodarone

Answer 28

4-35% have asympatomatic elevations in transaminases & bilirubin some get hepatitis

Question 29

GI abnormalities assc'd with amiodarone

Answer 29

N/V common | loss of taste, constipation

Question 30

amiodarone decreases effectiveness of what drugs (2)?

Answer 30

1. digoxin | 2. warfarin

Question 31

amiodarone increases effectiveness of what drugs (3)?

Answer 31

1. beta blockers 2. phenytoin 3. theophylline

Question 32

what is amiodarone primarily used for?

Answer 32

1. SVT (esp AF) 2. VT 3. VF

Question 33

contrast dronaderone to amioradone

Answer 33

Iodine-->CH3 = lower Vd, safer BUT less effective for A fib

Question 34

cardiac abnormalities for dronaderone

Answer 34

CONTRAINDICATED in patients with health failure

Question 35

AE: rash, nausea, diarrhea, mild QT prolongation, contraindicated in severe CHF

Answer 35

dronaderone

Question 36

what is a new agent used for acute conversion of AF to NSR, and for maintenance of NSR?

Answer 36

dofetilide

Question 37

which drug? HIGHER incidence of torsades than sortolol, HA, chest pain, dizziness. requires 3 day inpatient initiation.

Answer 37

dofetilide

Question 38

C/I: verpamil, cimetidine, trimethoprim, ketoconazole, prochlorperzine, megasterol

Answer 38

dofetilide

Question 39

how to tx pt with A fib with no other heart disease?

Answer 39

flecainide or propafenone

Question 40

how to tx pt with A fib with h/o CAD but normal EF?

Answer 40

sotolol

Question 41

how to tx pt with A fib with CHF?

Answer 41

amiodarone or dofetilide