Lecture 22: Heart Gross Anatomy

Question 1

what is another term for anterior IV branch

Answer 1

LAD (left anterior descending)

Question 2

what do cardiac veins accomplish

Answer 2

remove metabolic products from myocardium

Question 3

what do coronary arteries do

Answer 3

supply myocardium with oxygen

Question 4

what do arteries end in

Answer 4

arterioles then capillaries

Question 5

what is the basis of collateral circulation

Answer 5

anastemoses

Question 6

if an artery doesnt have an anastemosis what is it called

Answer 6

end artery

Question 7

what happens with occlusion of an end artery

Answer 7

necrosis of the tissue being supplied

Question 8

classic example of an end artery

Answer 8

central artery of the retina

Question 9

what happens with coronary occlusion

Answer 9

myocardial infarction (necrosis) and heart attack

Question 10

what happens with coronary insufficiency

Answer 10

myocardial ischemia and angina pectoris (cardiac/chest pain)

Question 11

3 most common areas of cardiac occlusion

Answer 11

RCA, LAD, circumflex

Question 12

what kind of gland is the heart

Answer 12

endocrine

Question 13

what kind of cells is the myocardium composed of

Answer 13

cardiac muscle cells (myocytes or cardiocytes), contractile cells, myoendocrine cells (atrial myocytes), conducting cells

Question 14

conducting cells of the heart

Answer 14

nodal cells, bundle branches, purjinke fibers

Question 15

how do cardiac muscle fibers in myocardium run

Answer 15

opposite directions, spirally around atria and ventricles

Question 16

complex spiral arrangements of ventricles explanation on a cellular level

Answer 16

Cardiac myocytes are separated by perimysium into
bundles/fascicles of various sizes with different
orientations

Question 17

how does ventricle contract (physical description)

Answer 17

like wringing of a towel

Question 18

length of cardiac myocytes

Answer 18

long lived

Question 19

what do cardiac myocytes accumulate in old age

Answer 19

lipofuscin pigment (yellow/brown, wear and tear)

Question 20

can cardiac myocytes regenerate

Answer 20

no

Question 21

describe the ECM of the heart

Answer 21

1) basal lamina form weave surrounding cardiocytes
2) elastic fiber bundles wrap around cardiocytes
3) collagen fibrils insert onto basal lamina
4) collagen fiber bundles form collage struts between neighboring cardiocytes

Question 22

atrial vs ventricular myocytes

Answer 22

smaller in size
fewer transverse tubules
have granules

Question 23

why is heart an endocrine organ

Answer 23

atrial myocytes synthesizes atrial natriuretic peptide (ANP) and store it in granules

Question 24

when is ANP released

Answer 24

in response to stretch of atrial wall - secreted by exocytosis into blood circulation

Question 25

what does ANP do

Answer 25

blocks sodium reabsorption in renal tubules thereby promoting sodium and urine excretion

Question 26

what is the atrioventricular bundle called and composed of

Answer 26

bundle of his

L and R ventricular bundle

Question 27

where are purjinke fibers

Answer 27

sub endocardium