heart 2 drugs

Question 1

Class 1a anti-arrhythmic effect?

intermediate

Answer 1

Atropine-like (bind to m2 receptors) inhibit parasympathetic activity to increase SNS activity increase GR

Also block Ca2+ channels which reduce contractional force

Question 2

Class 1b anti-arrhythmic effect?

fast

Answer 2

CNS effect used as anesthetic

Question 3

Class 1c anti-arrhythmic effect?

slow

Answer 3

can cause cardiac death as slow causing ventricular fibrillation (rapid contraction)

Question 4

Class 2 anti-arrhythmic effect?

Answer 4

beta blockers reduce cAMP, reduced Funny channel opening causing bradycardia

can cause myocardial depression (reduce force of contraction as less Na+)

ALSO propanolol and first gen. can lead to bronchoconstriction due to B2 in lungs

Question 5

Class 3 anti-arrhythmic effect?

sotalol

Answer 5

Sotalol

blocks sodium and calcium
reduces b1 expression less SNS activation
also blocks alpha

Question 6

Amiodarone

Answer 6

class 3 anti-arrhythmic drug causes depolarisation during repolarisation (relative refractory)

TOXIC thyroid effect due to iodine can cause hypo/hyper

Question 7

Class 4 anti-arrhythmic effect?

Answer 7

PACEMAKERS

block L-VACC causing bradycardia as prolong contraction

Question 8

verapamil

Answer 8

class 4 anti-arrhythmic (block L-VACC) specificity for cardiac tissue

Question 9

Diltiazem

Answer 9

class 4 anti-arrhythmic (block L-VACC) specificity for both vascular and cardiac