Week 1: Thursday

Question 1

what are 4 properties similar to skeletal muscle

of cardiac muscle

Answer 1

1. striated
2. Ca2+/troponin/tropomyosin regulation of crossbridge cycle
3. sarcoplasmic reticulum stores and releases Ca2+
4. T tubules

Question 2

what are 2 properties similar to smooth muscle

of cardiac muscle

Answer 2

1. gap junctions
2. extracellular Ca2+ is required for contraction (Ca2+ induced Ca2+ release)

Question 2

what does the L-type Ca channel do (Ca2+L)

Answer 2

allows for Ca2+ ro emter cell

Question 3

what does the Ryanodine receptor (RyR2) do

Answer 3

allows for Ca2+ to move from SR to sarcoplasm

Question 4

what does the sarco/edoplasmic reticulum calcium ATPase (SERCA) pump do

Answer 4

allows for Ca2+ to move back into SR

Question 5

what does the Calcium ATPase pump do

Answer 5

actively pumps Ca2+ out of cell

Question 6

what does the sodium calcium exchanger (NCX) do

Answer 6

pumps Ca2+ out of cell in exchange for Na+

Question 7

what does the sodium potassium ATPase (NK ATPase) pump do

Answer 7

actively pumps NA+ out of cell and K+ into cell

Question 8

what does the right side of the heart do

Answer 8

pumps pulmonary circuit

Question 9

what does the left side of the heart do

Answer 9

pumps systemic circuit

Question 10

what is the cardiac cycle

Answer 10

events associated with the flow of blood through the heart during a single complete heartbeat

Question 11

what is systole

Answer 11

contraction of ventricles

Question 12

what is diastole

Answer 12

relaxation of ventricles

Question 13

why do valves open passively

Answer 13

due to pressure gradients

Question 14

what is end-diastolic volume (EDV)

Answer 14

volume of blood in ventricle at the end of diastole

Question 15

what is end-systolic volume (ESV)

Answer 15

volume of blood in ventricle at the end of systole

Question 16

what is stroke volume and the equation

Answer 16

volume of blood ejected from ventricle each cycle

SV = EDV - ESV

Question 17

what is ejection fraction (EF) and its equation

Answer 17

• measures heart efficiency
• fraction of EDV ejected during a heartbeat
• EF = SV/EDV

Question 18

what is cardiac output (CO) and its equation

Answer 18

• measures blood output per minute
• CO = SV x HR

Question 19

volumes and blood flow rates are ____ for the left and right sides of the heart

Answer 19

similar

Question 20

what is the systolic pressure on the left ventricle

Answer 20

~120 mmHG

Question 21

what is the systolic pressure on the right ventricle

Answer 21

~20 mm HG

Question 22

how does the difference in pressure impact cardiac muscle function of the left and right sides

Answer 22

the left side of the heart has to work harder - why left ventricular wall is so much thicker

Question 23

what is the “Lub” S1 sound

Answer 23

backflow hitting AV valves after they close at the start of ventricular systole

Question 24

what is the "dub" S2 sound

Answer 24

backflow hitting the aortic and pulmonary valves at the start of diastole * briefer, sharper, higher pitched

Question 25

what is the split second heart sound (split S2)

Answer 25

the second heart sound (dub) is split into two sounds * can be normal (inspiration) * can be pathological

Question 25

Answer 25

C - point A marks the beginning of isovolumetric contraction

Question 26

what is preload | strickly

Answer 26

the tension in the wall produced by the end-diastolic pressure

Question 27

what is preload | loosely

Answer 27

the end diastolic pressure

Question 28

what is afterload | strickly

Answer 28

the tension in the wall produced at the time of the opening of the aortic valve (during systole)

Question 29

what is afterload | loosely

Answer 29

the pressure at the time of the opening of the aortic valve

Question 30

what should occur in a healthy heart | Frank-Starling Relationship

Answer 30

* increased volume (pressure) results in increased force of contraction * stroke volumes of the left and right ventricles remain balanced

Question 31

what happens if balance is not maintained in the heart

Answer 31

blood accumulation in pulmonary or systemuc circulation can result

Question 32

what is the importance of length-tension relationship in cardiac muscle

Answer 32

* wide dynamic range that takes advantage of the increased active tension at longer lengths * large passive tenssion at peak active tension length * passive tension limit the degree of heart filling

Question 33

what two things can increase the force of contraction (tension)

Answer 33

1. adjust length 2. adjust contractility (Ca2+ concentration or sensitivity)

Question 34

what is the sympathetic response on the heart

Answer 34

* increase heart rate * increase contractility

Question 35

what is the parasympathetic response on the heart

Answer 35

* decreases heart rate * does not impact contractility

Question 36

where does norepinephrine bind and what division of the autonomic nervous system is this

Answer 36

* B-adrenergic receptors * sympathetic response

Question 37

where does acetylcholine bind and what division of the autonomic nervous system is this

Answer 37

* muscarinic cholinergic receptors * parasympathetic

Question 38

what is EDV affected by

Answer 38

* venous return * vetricular compliance * diastolic filling time

Question 39

what is ESV affected by

Answer 39

* ventricular contractility * afterload

Question 40

what are murmurs

Answer 40

abnormal disruptions in flow (turbulence) that can be auscultated | can occur in diastole, systole, or continuous

Question 41

what does incompetent or insufficient mean | murmur

Answer 41

valve that failts to close completely | diastole

Question 42

what is regurgitation

Answer 42

backflow across the incompetent valve

Question 43

what is stenosis

Answer 43

valve fails to open widely enough | systole

Question 44

what is thrill

Answer 44

when murmur is so extreme that it can be palpated

Question 45

the defects that cause the murmur can lead to: (list 3)

Answer 45

1. abnormal blood flow 2. abnormal blood pressure 3. cardiac hypertrophy