Cardiovascular (year 2)

Question 1

what may want to be affected using cardiac pharmacology? (7)

Answer 1

heart rate/rhythm
contractility
relaxation of ventricles
preload
afterload
perfusion
arterial pressure

Question 2

what do positive inotropes do?

Answer 2

increase contractility

Question 3

what do negative inotropes do?

Answer 3

decrease contractility

Question 4

what do positive lusiotropes do?

Answer 4

increase relaxation

Question 5

what do negative lusiotropes do?

Answer 5

decrease relaxation

Question 6

what do positive chronotropes do?

Answer 6

increase heart rate

Question 7

what do negative chronotropes do?

Answer 7

decrease heart rate

Question 8

where is cardiac rate controlled?

Answer 8

cardiovascular centre in the medulla oblongata

Question 9

what nervous system controls the cardiac rate?

Answer 9

autonomic nervous system

Question 10

what is conduction of cardiac action potentials reliant on? (3)

Answer 10

normal Na, K, Ca channels
normal intra/extracellular Na, K, Ca levels
functioning interacted discs

Question 11

what do tachyarrhythmias decrease?

Answer 11

diastolic filling time and hence cardiac output

Question 12

what does increased cardiac work result in?

Answer 12

myocardial hypertrophy

Question 13

what can be done to treat tachyarrhythmias? (2)

Answer 13

reduce firing rate

slow conduction of impulses

Question 14

what are the classes of antidysrhythmics?

Answer 14

I
II
III
IIII
miscellaneous

Question 15

what do class I antidysrhthmics block?

Answer 15

sodium channels

Question 16

what do class II antidysrhthmics block?

Answer 16

beta blockers (beta1)

Question 17

what do class III antidysrhthmics block?

Answer 17

potassium channels

Question 18

what do class IV antidysrhthmics block?

Answer 18

calcium channels

Question 19

what sodium channels do class I antidysrhythmic block?

Answer 19

fast

Question 20

where are fast sodium channels present?

Answer 20

cardiac myocytes (doesn’t effect nodal tissue)

Question 21

what do class I antidysrhythmic cause?

Answer 21

slower depolarisation

Question 22

what does use dependant sodium channel blockade mean?

Answer 22

preferentially bind to open/refractory sodium channels over resting ones

Question 23

why is it significant that class I antidysrhythmics don’t effect nodal tissues?

Answer 23

reduce tachyarrhythmias but doesn’t effect normal heart rates

Question 24

what do class I antidysrhythmics depend on being normal to function properly?

Answer 24

extracellular potassium (hypokaleamia reduces function)