IPathophysioloyg of ischaemia and infraction

Question 1

Ischaemia

Answer 1

lack of blood supply to tissue/ organ leading to inadequate 02 supply to meet needs of tissue/organ

Question 2

what are the types of hypoxia

Answer 2

hypoxic, aneami, stagnet, cytotoixc, histologic

Question 3

hypoxic hypoxia

Answer 3

lack of inspiroed o2 , or low pa02 with normal inspired o2

Question 4

what is stagnet hypoxia

Answer 4

normal inspired o2 but abnoral deliver e.g. occlusion of a vessel or systemic

Question 5

what is cytotoxic hypoxia

Answer 5

nrma inspbired oxygen but abnormal at tissue level

Question 6

what are hte 6 factors effecting oxygen supply

Answer 6

inspired o2, pulmonary function, blood consituents, blood flow, integrity of vasculature, tissue mechanism

Question 7

what factors affect o2 demand

Answer 7

tissue its self - ie differt tisuse have differ oxygen demands
activity of tissue above baseline value

Question 8

what suppply issues can lead to ischeamic heart disease

Answer 8

cornary artey atheroma, cardiac failure, pulmonar funtio , pulmary odema , lvf, anaemiak, previous mi

Question 9

what demand issues can lead to ischeamic heart diese

Answer 9

heart havign high intrinsic demand, exertion and stress

Question 10

what type of angina is seen if tehr is an esatbliced atheroma in a coronary artery

Answer 10

stable

Question 11

what type of angina is seen is there is a complicated atheroma in a coronary atrery

Answer 11

unstable

Question 12

what is the effect of an atheromatous on blood flow and pressure of radis decrasing by half

Answer 12

increaed blodo pressure by factor of 16

Question 13

what are the differt types of ischeame

Answer 13

acutre, chronic, acute on chronic

Question 14

what are the biochemical effects of ischaemia

Answer 14

ther is an increae in lactate produced by anerobic metablis, this increase pyruvate, leading to increase acetyl coa + co2 +nadh, there is insufficient energy and cell death ocras

Question 15

which die quicker cells with high or low metabolic rate when starved of 02

Answer 15

high

Question 16

what are the 3 clincal effect oischameia

Answer 16

pain, dysfuoin and physicall damage

Question 17

what are the outcome for iscame

Answer 17

no clinal effect
resoluoin
infration

Question 18

infraction

Answer 18

the occuloin of arteri supply or venou drainge, resultin in iscaheami necrosis

Question 19

what are examples of cessation of blood flow leading to infraction

Answer 19

thrombosis, embolism, strangulation e.g gut, trauma

Question 20

what factors effect the scale of damage of ischemai

Answer 20

time
tissue /organ
pattern of blood supply
previous disease

Question 21

what is coagulative necrosis and where does it occur

Answer 21

anywher except the brain, wher blood flow is stoped or slowed down as a result of iscehmai

Question 22

what is colliquitive necorsis and wher does it occur

Answer 22

it is when the dies cells die and perfuation into the blood stream, thus stoping the blood flow to other cells, can happen anywhere including the brain

Question 23

what cells die in a mi

Answer 23

myocyte death

Question 24

how long does it take heart cells during myocardial ischemia to atp deplte

Answer 24

secondas

Question 25

how long does it take heart cells during myocardial ischemia to lose myocardial contractily

Answer 25

less than 2 minutes

Question 26

how long does it take heart cells during myocardial ischemia to to have ultrastrucula changes and what are these

Answer 26

a few minues myofibrillar rexlation, glycogen depletion, cell and mitochonal swelling

Question 27

how long does it take heart cells during myocardial ischemia to have yocyte necotis and what is this

Answer 27

distuptio of integiry of sarcolemmal memabne and leakage of intercllaru macromolues within 20-40 minues

Question 28

how long does it take for injry to the microvasculature

Answer 28

greater than 1 hour

Question 29

how to detect leackage of intracellau macromolues

Answer 29

blood tests

Question 30

what does a infration look like with less than 24 hours

Answer 30

slight swollen mitochonai on electon micros after a few hours to 24 hours

Question 31

what is te apperance of infracts after 24-48 hours

Answer 31

pale infraction - myocarium, spleen, knidys red inflact, lung , liver loose tissues, microsoppy acute inflation initial at the edge of the infract, loss of speicl cell features

Question 32

what is the apperance of infracts after 72 hours

Answer 32

macroscopically - pale infract, yellow white and red periphery red impact little change microscopy - chroin inflation, macrophage, granuat tissu forming, fibrois

Question 33

what is the end result of infaracts

Answer 33

scare replaces are of tisue damage, shape depend o teriary of occuled fevsl reperfusion injury

Question 34

what happen in the first 4-8 ours after an mi

Answer 34

early coagulation necosi, oedema, haemoarage

Question 35

what happens 12-48 hours after an mi

Answer 35

ongin coagulation, necrosi, myocyte chanes, early neutrophillic infilatatio

Question 36

what happens 1-3 days after an mi

Answer 36

coaguation necros, loss of nuclei and striation, brisk neutiphillic infalte

Question 37

what happesn 3-7 days after an mi

Answer 37

disintegration of dead myogiber, dying neutrophils, early phagocytois

Question 38

what happens 7-10 days fater an mi

Answer 38

well developed phagocytois, granuatio tissue at margin

Question 39

what happens 10-14 days after an mi

Answer 39

well estabiled granulation tissue with new blood vessels and collagen deposistion

Question 40

what happens 2-8 weeks after an mi

Answer 40

increased collagen deposion and decreaed celluarity

Question 41

what happens after 2 monts afer an mi

Answer 41

dense collagenous scar

Question 42

what does a tranmurla infraction effect

Answer 42

the whole thickenss of the myocardium

Question 43

what does asubendocaril infatio effect,

Answer 43

mostly limited to the zone of myocaridum under the endocarial ling of the heart

Question 44

what differ between a subendocaril infraction and a transmural infration

Answer 44

repair time

Question 45

how is a non stemi herat attack diage

Answer 45

elevated troponin

Question 46

what type of heart attack is anon stemi through to be

Answer 46

subendocardial