Mod 5: action potentials ekg

Question 1

ventricular action potentials
phase 0
1
2
3
4

Answer 1

0-rapid depolarization (Na influx)
1-initial repolarization (na channels close, K leaves slow)
2- plateu (Ca influx {contraction} balances K efflux)
3-rapid repolarization (massive K efflux, Ca closes)
4-RMP -85mV (^k permeability)

Question 2

Atrial action potentials
0
3
4

Answer 2

0-depolarize (open Ca)
3-repolarization (close Ca and open K)
4-slow depolarization (spontaneous Na influx)= automaticity

Question 3

Adenosine and Acetylcholine effect on HR

Answer 3

vHR d/t vDepolarization rate

Question 4

Catecholamines effect on heart rate

Answer 4

^HR d/t ^Depolarization rate

Question 5

anti-arhythmic drugs
class 1
2
3
4

Answer 5

1. blocks sodium channels
2. B-blocker
3. prolongs AP by blocking K efflux
4. Ca channel blocker

Question 6

prolonged QT=^ risk for

Answer 6

ventricular arrhythmias

Question 7

QRS=ventricular ____

Answer 7

depolarization

Question 8

QT interval = ventricular

Answer 8

contraction

Question 9

ST segment= ventricular

Answer 9

depolarization

Question 10

U wave present in

Answer 10

bradycardia

Question 11

Beta1

Answer 11

increase contractility, HR, renin

Question 12

Beta2

Answer 12

vasodilation, bronchodilation

Question 13

Alpha1

Answer 13

vasoconstriction

Question 14

Dopamine

Answer 14

vasodilation

Question 15

epi

Answer 15

B1
B2 AND a1, simultaneous stimulation= no change
^dose, a1 overrides B2
(^CO)

Question 16

Norepi

Answer 16

B1, A1

Question 17

Dopamine 
low
moderate
high
Dobutamine

Answer 17

low-dopamine 1
moderate-B1
High-a1
dobutamine -B1