Exam 2: Cardiac Mechanics Paper

Question 1

blood pressure

Answer 1

pressure of circulating blood against blood vessel walls

Question 2

cardiac output

Answer 2

SV X HR

the amount of blood your heart pumps each minute (mL/min)

Question 3

stroke volume

Answer 3

amount of blood ejected from the heart during each contraction

Question 4

preload

Answer 4

initial cardiac muscle fbre length prior to contraction
max amount of blood in left ventricle prior to contraction
LVEDV

Question 5

afterload

Answer 5

tension developed in cardiac muscle fibres before shortening occurs (contraction)
resistance to lef ventricular outflow
force preventing ejection - pressure on the ASV

Question 6

contractility

Answer 6

degree of inotropy

ability of cardiac muscle to do work with a given preload and afterload

Question 7

what is an inotrope

Answer 7

medicine that changes the force of the heart’s contraction
+ inotrope: inc strength of heartbeat - pumps more with fewer beats, stroke volume increases
Caclium chloride and Levosimendan are + inotropes

Question 8

starling’ law of the heart

Answer 8

stroke volume in the LV will increase as the left ventricular volume increases
cases a more forceful systolic contraction

it is the change in preload ~ end diastolic volume

directly results in a change in stroke volume

Question 9

MAP =

Answer 9

CO X SVR

Question 10

what wave on a QRS precedes atrial systole

Answer 10

P wave

Question 11

what wave precedes ventricular systole

Answer 11

QRS

Question 12

central venous pressure

Answer 12

pressure in venacava near RA

measure of blood returning to the heart

Question 13

stenosis

Answer 13

narrowing of blood vessels, heart has to work harder to pump blood into aorta and to rest of body

Question 14

cardiac tamponade

Answer 14

when extra fluid builds up in the space around the heart

puts pressure on the heart, prevents it from pumping propely

Question 15

what is pulmonary artery wedge a measure of?

Answer 15

represents LA pressure
- measure of how much fluid s=is in the body on the left side of heart stick swan neck catheter into right side of heart and blow up balloon
an index of CHF

Question 16

higher inotropy leads to

Answer 16

increased cardiac output

Question 17

vagolytic agent

Answer 17

reduces vagal tone - reduces parasympathetic activation through muscarinic recepor blocking
- atropine is a vagolytic agent: acetylcholine antagonist
antagonist for parasympathetic activation so it inc chronotropy leads to inc sympathetic activation
- atropine is also a + inotrope

Question 18

“refractory to pharmacological treatment”

Answer 18

not responding to drugs/treatments

Question 19

alpha 1

Answer 19

vasoconstriction, inc SVR (systemic vascular resistance), inc MAP, mydriasis (dilating pupils), closure of bladder, sphincter

Question 20

alpha 2

Answer 20

inhibits noradrenaline, acetylcholine and insulin release sedation, analgesia (inability to feel pain)

Question 21

B1

Answer 21

heart sympathetic response

Question 22

B2

Answer 22

lungs sympathetic response

Question 23

adrenaline

Answer 23

weakly stimulates B1/2 at low doses, strongly stimulates A1/A2 at high doses

Question 24

noradrenalne

Answer 24

strongly stimulates A1 and A2

Question 25

Phenylephrine

Answer 25

stimulates alpha 1

Question 26

Dobutamine

Answer 26

stimulates B1

Question 27

ischemia

Answer 27

lack of blood supply