Antiarrhythmics

Question 1

Class I antiarrhythmics in general

Answer 1

Are Na channel blockers. Toxicity made worse by hyperkalemia

Question 2

Class 1A Antiarrhythmics

Answer 2

Quinidine procainamide disopyramide

Lengthen action potential, increase ERP. Lengthen QT.

Question 3

Class 1A antiarryhtmics side effects

Answer 3

Cinchonism, SLE-like snydrome, TORSADES de POINTES

Question 4

Class 1B antiarrythmics

Answer 4

Lidocaine, Mexiletine

Decrease action potential duration.

BEST FOR POST MI ARRHYTHMIA PROTECTION

Question 5

Class IC antiarrhythmics

Answer 5

Flecainide, Propafenone

Don’t change length of action potential. Increase refeactory period. Contraindicated in ischemic and structural HD

Question 6

Class II antiarrhythmics

Answer 6

Beta blockers
Increase the length of class IV of the SA and AV node action potential. Increase PR interval because AV node is particularly sensitive.

TREAT OVERDOSE WITH GLUCAGON

Question 7

Class III antiarrythmics

Answer 7

Amiodarone, Ibutilide, dofetilide, sotalol

K blockers. LEngthen AP duration, increase QT.

Question 8

Class IV antiarrhythmics

Answer 8

CCB

Decrease conduction velocity. Increase pr interval. Cause constipation flushing edema

Question 9

Adenosine

Answer 9

Increase K outflow, prevent Ca inflow. Abolish SVT. Very short acting.

Question 10

How to abolish torsades

Answer 10

Mg2+