Heart lecture 3

Question 1

Period between start of heartbeat and the next

Answer 1

Cardiac cycle

Question 2

Phases of cardiac cycle step 1

Answer 2

Cycle begins, everything relaxed (diastole)

Question 3

atrial systole

Answer 3

Atrial systole, atria contracts, fills ventricles

Question 4

How atrial systole works?

Answer 4

SA node fires, atriums contract

Question 5

End of atrial systole/ventricular diastole measurement

Answer 5

End diastolic volume (EDV)

Question 6

Phases of cardiac cycle step 3: Atrial diastole

Answer 6

atria relax, signal continue thru heart

Question 7

Phases of cardiac cycle step 4/5:

Answer 7

Ventricular systole (2phases)

Question 8

Ventricular systole phase 1

Answer 8

Ventricular contraction - prior to semilunar valves

Question 9

Contraction with no volume change

Answer 9

Isovolumetric contraction

Question 10

Ventricular systole phase 2

Answer 10

Ventricular ejection - semilunar valves open, blood leaves

Question 11

Pressure needed to open semilunar valves

Answer 11

LV: >80mmHg
RV: >20mmHg

Question 12

Remaining volume in each ventricle after systole

Answer 12

End systolic volume

Question 13

Phases of Cardiac cycle step 6: Ventricular diastole

Answer 13

Ventricular diastole - ventricles relax, pressure drops, valve closing

Question 14

Isovolumetric relaxation

Answer 14

valves closed, blood passively fill atria

Question 15

Phases of cardiac cycle step 8: late ventricular diastole

Answer 15

Ventricular diastole- late - chambers relaxed - ventricles passively fill ~70%

Question 16

Ventricular diastole how long?

Answer 16

400msec

Question 17

State of ventricles and atria during ventricular diastole

Answer 17

Relaxed

Question 18

pressure aortic valve closes

Answer 18

100mmHg

Question 19

What happens when ventricular pressure drop below atrial

Answer 19

AV valves open

Question 20

How does aortic valve open

Answer 20

Pressure changes in aorta

Question 21

aortic valve closing causes what?

Answer 21

short pressure rise

Question 22

What is dicrotic notch

Answer 22

Valley in pressure tracing by short pressure rise

Question 23

What is the process of listening to body sounds? What tool used for it

Answer 23

Auscultation

Stethoscope

Question 24

How heart sounds produced

Answer 24

blood turbulance from closing valves

Question 25

Heart sounds s1 , s2 , s3, s4

Answer 25

S1 - av valve close, start contraction s2 - semilunar valves close s3 - very feint s4 - pathologic

Question 26

Abnormal heart sound name

Answer 26

Heart murmurs

Question 27

What could heart murmurs indicate

Answer 27

valve insufficiency

Question 28

What's cardiac output

Answer 28

total blood ejected from left ventricle per min

Question 29

Cardiac output (CO) formula

Answer 29

CO = Heart rate x Stroke volume

Question 30

Stroke volume formula

Answer 30

End-diastolic volume - End-systolic volume

Question 31

What is cardiac reserve

Answer 31

different between max CO and CO at rest

Question 32

How much average cardiac reserve?

Answer 32

4-5 times resting value

Question 33

where autonomic regulation occurs

Answer 33

cardiovascular center of the medulla oblongata

Question 34

How autonomic regulation works

Answer 34

Uses signals from sensory receptors - increase or decrease nerve receptors

Question 35

baroreceptors input signals from

Answer 35

pressure changes

Question 36

Chemoreceptors input signals from

Answer 36

chemical changes in blood

Question 37

proprioceptors input signals from

Answer 37

sensory from limbs/extremities

Question 38

Cardiac centers of medulla oblongata

Answer 38

Cardioinhibitory center Cardioacceleratory center

Question 39

Cardioinhibitory center

Answer 39

slows heart rate via vagus nerve

Question 40

Cardioacceleratory center

Answer 40

controls sympathetic neurons. increase heart rate

Question 41

Where cardiac accelerator nerves located? What travels through it

Answer 41

Thoracic spine. Sympathetics

Question 42

What travels thru Vagus nerve

Answer 42

parasympathetics

Question 43

What is released during sympathetic influence to increase heart rate

Answer 43

Norepinephrine

Question 44

what is released during parasympathetic influence to decrease heart rate

Answer 44

Acetylcholine

Question 45

Chemical factor affecting HR

Answer 45

Electrolyte imbalance, hormones

Question 46

3 main factors regulating stroke volume

Answer 46

Preload Contractility Afterload

Question 47

What is preload

Answer 47

Degree of heart stretch before contract

Question 48

Frank starling law

Answer 48

higher volume blood = more stretch and greater contraction

Question 49

Contractility

Answer 49

strength of fiber contraction

Question 50

What substances affect contractility

Answer 50

positive (increase contraction) and negative (decrease contraction) ionotropic agents

Question 51

Afterload

Answer 51

pressure needed for semilunar valves to open

Question 52

Loss of pumping efficiency called

Answer 52

Congestive heart failure

Question 53

Abnormal rhythm of heart pathology

Answer 53

Arrhythmia

Question 54

Arrhythmia cause

Answer 54

Defect in heart conduction system

Question 55

Accumulation of atherosclerotic plaque causes

Answer 55

Coronary Artery disease

Question 56

Defects present from birth called

Answer 56

Congenital heart defects

Question 57

Segment of aorta narrowed

Answer 57

Coarctation of aorta

Question 58

Ductus arteriosus remains open rather than closing

Answer 58

Patent Ductus Arteriosus

Question 59

Fetal foramen ovale fail to close

Answer 59

Atrial Septal defect

Question 60

Incomplete development of septum

Answer 60

Ventricular Septal Defect