Chapter 7 - Cardiac Physiology 2

Front 1

1. systole

2. diastole

Back 1

1. contraction and emptying

2. relaxation and filling

Front 2

Stages in cardiac cycle (9)

Back 2

1. early ventricular diastole

2. late ventricular diastole

3. end of ventricular diastole

4. ventricular excitation and onset of ventricular systole

5. isovolumetric ventricular contractoin

6. ventricular ejection

7. ventricular repolarization and onset of ventricular diastole

8. isovolumetric ventricular relaxation

9. ventricular filling

Front 3

1. Early ventricular diastole

Back 3

atrium still in diastole condition -> (corresponds to TP interval) -> venous blood continues to flow into atria causing more pressure in atria than ventricle (1) -> causes AV valves to open -> ventricle volume slowly rises before atrial contraction (2)

Front 4

2. Late ventricular diastole

Back 4

SA node reaches threshold and fires -> impules spread throughout atria -> (corresponds to P wave) (3) -> atrial depol, so atria contracts -> causes atrial pressure to rise (4) -> as more blood enters, vent press. rises after atrial contraction (5) -> additional blood flows in ventricle (6)

Front 5

3. End of ventricular diastole

Back 5

in this stage, atrial contraction and ventricular filling is complete (7) -> End Diastolic Volume = EDV = 135 ml -> no blood will be added

Front 6

4. ventricular excitation and onset of ventricular systole

Back 6

impulse passes through AV node and conduction system to vent. -> causes vent. excitation -> (corresponds to QRS comp) (8) -> causes HIGHER ventricular pressure than atria (9) -> causes AV valves to close

Front 7

5. isovolumetric ventricular contraction

Back 7

increase in vent. pressure -> causes aortic valve to open -> between AV closure and aortic valve opening, ventricle remains closed chamber for brief moment (10) -> no blood enter or leaves vent. -> this interval is isolvolumetric vent. contraction -> due to continuous contraction, vent. pressure continue to rise as volume remains CONSTANT (11)

Front 8

6. Ventricular ejection

Back 8

ventricle doesn't empty completely -> during ejection only half blood is ejected -> remaining amount of at end of systole (15) -> referred to as End Systolic Volume ESV = 65ml (15)

Front 9

ESV =

Back 9

amount of blood remaining in ventricle after ejection

Front 10

7. Ventricular repolarization and onset of ventricular diastole

Back 10

(represents T wave) -> end of ventricular systole (16) -> repolarization of ventricle occurs -> causes decrease in ventricular pressure compared to aortic pressure (17) -> aortic valve closes and causes notch on aortic pressure curve (dicrotic notch) (18) -> blood enters vent.

Front 11

8. Isovolumetric ventricular relaxation

Back 11

AV valves not open yet -> ventricular pressure still exceeds atrial pressure -> no blood enters the ventricle from atrium -> all valves closed for a brief time (isovolumetric vent. relaxation) (19) ventricle vol. remains constant during isovol. vent. relax. (18) -> no blood enters or leaves vent. continues to relax

Front 12

9. Ventricular filling

Back 12

decrease in ventricular pressure compared to atrial (21) -> ventricular filling begins -> atrial depolarization and ventricle repolarization occus at same time -> atrial diastole takes place during ventricular systole -> blood enters atria -> increase in atria press. (22) -> blood enters vent. -> vent. filling takes place (23) -> ventr. filling slows (24)

Front 13

1. the lub sound comes from

2. characteristics of lubb sound

3. caused by

4. signals the onset of

Back 13

1. closing of AV valves

2. low pitched, soft and long

3. ventricular contractoin

4. ventricular systole

Front 14

1. What is the dubb soud from

2. characteristics of dubb sound

3. caused by

4. signals onset of

Back 14

1. closing of pulmonary semilunar valve

2. higher pitch, shorter, sharper

3. fall in ventricular pressure than aortic and pulm. artery press.

4. onset of ventricular diastole

Front 15

What sound comes first? Lubb or Dubb

Back 15

1st = lubb

2nd = dubb

Front 16

WEEK 3

1. What does the heart begin as during embryonic development?

2. what is developed but incomplete?

Back 16

1. two separate tubes that loop around e/o

2. septa, foramen ovale

Front 17

WEEK 4

1. hear beats?

2. circulation

3. ductus arteriosus

4. blood returns to placenta via

5. umbilical veins carries

Back 17

1. with regular rhythm

2. pattern of circulation altered to supply vital organs with o2 blood

3. shunts blood from pulmonary artery to aorta by passing the lungs

4. umbilical veins

5. o2 blood from placenta to body of fetus

Front 18

What closes at birth due to decreased flow from placenta and increased left aterial pressure

Back 18

foramen ovale

Front 19

Year 1 the foramen ovale becomes

Back 19

fossa ovalis

Front 20

Physical position of the heart

1. during infancy compared to adult

Back 20

- heart is more horizontal on thorax

- apex at 3 or 4 intercostal space instead of 5th in adult

- lateral to mid-clavicular line

Front 21

Weight of heart at

1. 9 y/o

2. puberty

Back 21

1. as heavy as it was at birth

2. 10x as heavy

Front 22

At age 80

Back 22

LV will atrophy up to 25% compared to 25 y/o

Front 23

1. Affects of aging on contraction and refractory period

2. Aging and heart contractability

3. effect on pacemaker cells

4. hear recovery

Back 23

1. long contraction duration and longer refractory period - takes longer to reach peak force

2. AV valves thicken and mitral valves calcify (heart contractability not as efficient)

3. decrease in pacemaker cells

4. slower

Front 24

Maximum heart rate decreases about ____________ every _________

Back 24

5-10 beats every decade

Front 25

Age related changes in blood vessels

Back 25

1. changes in tunic intima and T media (contribute to hypertension)

2. changes internal layers in arteries leaving them more vulnerable to atherosclerosis

3. systolic pressure increase more than diastolic pressure due to stiffness in blood vess

4. BP increase