Antiarrhythmic drugs

Question 1

four common causes of arrhythmias

Answer 1

heart failure
anesthetized patients
MI
anti-arrhythmic drugs

Question 2

what are the 3 requirement for normal cardiac excitation

Answer 2

pacemaker
conduction fibres
healthy myocardium capable of robust excitation-contraction coupling

Question 3

define arrhythmia

Answer 3

any hythm that is not a normal sinus rhythm with normal AV conduction

Question 4

what is the main pacemaker of a heart beat

Answer 4

SA node

Question 5

rate of SA node

Answer 5

60-100 beats per minute

Question 6

discharge rate of AV node

Answer 6

40-60bpm

Question 7

what does the AV node do

Answer 7

electrical connection between atria and ventricles that delays conduction of acction potential by 0.1 seconds to allow atria to contrat and ventricles to fill

Question 8

function of conduction fibres

Answer 8

excite the ventricular mass as near simultaneously as possible

Question 9

discharge rate of purkinje fibres

Answer 9

20-40bpm

Question 10

describe the action potential

Answer 10

SA node pacemaker impulse
conduction to atrria 
AV node
bundle of His- Purkinje fibers
ventricular myocardium 
contraction

Question 11

p wave

Answer 11

atrial depol

Question 12

QRS complex

Answer 12

ventricular depol

Question 13

T wave

Answer 13

ventricular repol

Question 14

PR interval

Answer 14

conduction time atria to ventricles

Question 15

GRS interval

Answer 15

tim for all ventricular cells to be activated

Question 16

QT interval

Answer 16

duration of ventricular action potential