Antiarrythmics pt 3

Question 1

Class 1 drug that does not prolong action potential duration and QT interval duration of the ECG, and are

Answer 1

1c

Question 2

Answer 2

class 1c

Question 3

depolarization to the threshold opens m-gates greatly increasing sodium permeability

Answer 3

class 1a and 1b

Question 4

h-gates are closed, inward sodium flux is inhibited, the channel is not available for reactivation – this state is responsible for the refractory period

Answer 4

class Ib drugs

Question 5

Ectopic pacemaker cells with faster rhythms will be preferentially targeted

Answer 5

class 1a

Question 6

Dissociate from Na channel with intermediate kinetics

Answer 6

class 1a drugs

Question 7

Preferentially bind to depolarized cells

Answer 7

class 1b

Question 8

Dissociate from Na channel with fast kinetics – no effect on conduction in normal tissue

Answer 8

class 1b drugs

Question 9

1. More specific action on sodium channels –
   
   1. do not block potassium channels
   2. do not prolong _action potential or QT duratio_n on ECG

Answer 9

class 1b drugs

Question 10

state dependent drugs of class 1

Answer 10

class 1a and class 1c

Question 11

Dissociate from channel with slow kinetics

Answer 11

class 1c drugs