Homeostasis and Heart Failure

Question 1

What is the function of the heart and blood?

Answer 1

move O2, electrolytes, and hormones to meet metabolic needs

removes wastes from oxidation (CO2, etc)

Question 2

what is heart failure (HF)?

Answer 2

the heart is unable to contract optimally to pump blood at a rate sufficient to meet requirements of metabolic organs

Question 3

what are some symptoms of HF?

Answer 3

breathlessness
fatigue
pitting edema
hepatomegaly

Question 4

what causes breathlessness in HF?

Answer 4

blood backing up into pulmonary veins

indicates left sided HF

Question 5

what is a heart attack?

Answer 5

myocardial infarction (MI) (loss of heart muscle due to stoppage of blood flow)

Question 6

what are some risk factors of MI becoming HF? (8pts)

Answer 6

genetics
gender
smoking
diet
personality (Type A)
stress
social stratum
alcoholism

Question 7

what are some causes of a heart attack? (6pts)

Answer 7

essential hypertension
diabetes
idiopathic primary cardiomyopathy
viral heart infection
cardiac valve disease
associated abnormalities

Question 8

what 3 components make up the cardiovascular (CV) system?

Answer 8

heart
blood vessels
blood

Question 9

how does pressure affect blood movement?

Answer 9

blood moves from area of high pressure (LV) to an area of low pressure (capillary beds)

Question 10

what is the function of the blood vessels?

Answer 10

delivery mechanisms for blood

Question 11

what are the 2 separate loops of the circulatory system?

Answer 11

pulmonary - heart and lungs

systemic - heart and peripheral organs

Question 12

do the left and right sides of the heart pump out the same amount of blood per beat? what is the difference between them in terms of pressure?

Answer 12

yes

left side has a lot higher pressure

Question 13

what is the septum? what is its function?

Answer 13

separates left and right ventricle

prevents mixing of oxy and deoxy blood and contributes to cardiac pump function

Question 14

outline the pathway blood would take to complete one cycle of the CV system starting with the IVC/SVC. indicate when the blood is deoxy or oxy.

Answer 14

IVC + SVC (deoxy)
RA
RV
pulmonary artery
lung (gas exchange)
pulm vein (oxy)
LA
LV
aorta
arteries
capillaries (gas exchange)
veins (deoxy)
IVC and SVC

Question 15

what are the two main sets of valves in the heart?

Answer 15

AV valves

semilunar valves

Question 16

what is the function of the AV valves?

Answer 16

prevent blood from going in atria when they contract

Question 17

how do the AV valves stay closed during contraction?

Answer 17

increased ventricular pressure keep em closed

anchored by chordae tendinae

Question 18

what are the two different AV valves?

Answer 18

Right AV = tricuspid

Left AV = mitral

Question 19

what is the function of the semilunar valves?

Answer 19

govern blood flow where major arteries leave the ventricles

Question 20

are the semilunar valves muscular?

Answer 20

no

passively open and close

Question 21

what are the two different semilunar valves?

Answer 21

Left = aortic valve
Right = pulmonary valve

Question 22

what is the heart composed of?

Answer 22

spirally arranged cardiac myocytes that form an electrical synctium

Question 23

what are intercalated discs?

Answer 23

junctions that connect myocytes

Question 24

what are two structural components found throughout the cardiac ultrastructure?

Answer 24

gap junctions (low resistance regions)
desmosomes (structural anchoring)

Question 25

what are the three layers of the heart?

Answer 25

endocardium (endothelial tissue)
myocardium (muscle)
epicardium (thin external membrane)

Question 26

how do electrical signals work in the heart?

Answer 26

electrical signals spread from cell to cell as one
Atria and ventricles are electrically isolated via non-conductive fibrous skeleton, but share specialized connections or “wirings”

Question 27

what is special about cardiac myocytes?

Answer 27

they possess a lot of mitochondria

no new heart cells generated after birth, they only increase in cell size

Question 28

what is the pericardial sac and pericardial fluid?

Answer 28

sac - holds heart in place

fluid - reduces friction