week 5 patho

Question 1

what does the term ischemia mean

Answer 1

inadequate blood supply to things due to blockage of blood vessels

Question 2

what is infarction

Answer 2

injury/death to tissue

Question 3

what is unstable angina

Answer 3

there’s an MI coming on

Question 4

what happens when you block angio 2

Answer 4

vasodilation and fluid secretion, high potassium

Question 5

what is depolarisation

Answer 5

when the heart goes from negatively charged to positive resulting in contraction

Question 6

what is the pathway for heart conduction

Answer 6

SA - AV- bundle of HIS, L and R bundle branches, purkinjie fibres

Question 7

what are the four properties of cardiac cells

Answer 7

automaticity, contractility, conductivity, excitability

Question 8

what kinds of things can an ECG detect

Answer 8

abnormalities in cardiac conduction, ischemia, infarction, hypertrophy, electrolyte abnormalities

Question 9

what would the sinus rhythm of cardiac conduction generated by the AV node be like

Answer 9

60-40 beats per minute, using AV as backup pacemaker means it’ll be a little delayed

Question 10

whats the difference between a 12 lead ECG and a continuous

Answer 10

12 lead will be for diagnosing and getting a rlly in depth look at the heart, continuous will be more for superficial monitoring

Question 11

what would an ECG look like in a patient with an NSTEMI

Answer 11

you will see ST depression (the space after QRS will be dipped_

Question 12

what would an ECG look like in a patient with full STEMI

Answer 12

you will see ST elevation, the space after QRS will be v high

Question 13

what should an ECG look like in a patient with high potassium

Answer 13

high and pointy T wave, wave is more spread out

Question 14

what should and ECG look like in a patient with low potassium

Answer 14

An additional U wave, long q wave, low or inverted T wave

Question 15

how does potassium affect heart contractility

Answer 15

high potassium can affect the ability to depolarise

Question 16

what could cause sinus bradycardia

Answer 16

vagal stimulation, medications, hypothermia

Question 17

how could sinus tachycardia lead to angina

Answer 17

coronary arteries fill during diastole, since diastole is shorter they aren’t filling enough, meaning the heart isn’t getting enough oxygen

Question 18

whats similar with all sinus rhythms (normal, tachycardia, brady)

Answer 18

waves don’t change, just the space in between them

Question 19

what is atrial fibrillation

Answer 19

heart goes haywire, atria pump at 600bpm, ventricles pump anywhere from 50-180 bpm, blood doesn’t actually move foreward

Question 20

why is there risk of blood clots with atrial fibrillation

Answer 20

blood doesn’t actually more foreward, thrombous may form due to venous stasis

Question 21

define heart failure

Answer 21

heart isn’t pumping as effectively as it should

Question 22

what are the 5 factors of cardiac output

Answer 22

contractility, HR, preload, afterload, blood volume

Question 23

what is a normal cardiac output

Answer 23

3-6 L/min

Question 24

what are the two biggest risk factors of heart failure

Answer 24

CAD because it reduces blood flow to the myocardium (responsible for cardiac pump)
HTn: resistance during afterload overworks ventricles

Question 25

what are two chronic causes of heart failure associated with contractility

Answer 25

CAD: impaired blood flow to myocardium cardiomyopathy: disease to heart

Question 26

what are two acute causes of heart failure associated with contractility

Answer 26

acute MI (side backflow of blood to the heart) myocarditis: inflammation of the heart muscle

Question 27

what are three causes of heart failure associated with afterload

Answer 27

HTN: heart has to work harder to overcome resistance Pulmonary disease: same as HTN in terms of heart needs to try and push blood through lungs hypertensive crisis: BP goes up quickly, heart can't overcome

Question 28

what do valvular disease and rupture of papillary muscle have in common

Answer 28

- both affect preload - valvular disease: valves aren't working - rupture: this muscle is involved with the opening and closing of valves, when it ruptures it causes regurgitation and back flow

Question 29

what are the two issues in valvular diseases

Answer 29

stenotic valves: too tight loose valves: don't close properly (can cause regurgitation)

Question 30

what is myocarditis

Answer 30

inflammation of heart muscle, affects contractility

Question 31

what is ejection fraction

Answer 31

the percentage of blood during end diastolic volume that actually ejected from the heart during diastole (there's always a bit remaining)

Question 32

what is a critical number for ejection fraction that could mean that the heart is failing

Answer 32

less than 40%

Question 33

what are some characteristics of heart failure with reduced injection fraction

Answer 33

it means there's a pumping problem, left ventricle cannot contract strong enough to pump blood effectively heart muscle damaged from being overworked usually includes an ejection fraction less than 40 %

Question 34

what are characteristics of heart failure with preserved injection fraction

Answer 34

means there's a filling problem, inability for ventricles to relax and fill during diastole usually from ventricular hypertrophy

Question 35

what are the four compensatory mechanisms for heart failure

Answer 35

1. SNS activation 2. neurohormonal response (RASS) 3. ventricular dilation 4. ventricular hypertrophy

Question 36

what are the two cardiac enzymes that work against all compensatory mechanisms of the heart

Answer 36

ANP and BNP (they increase urinary output and trigger vasodilation)

Question 37

what is the difference between right sided and left sided heart failure

Answer 37

left sided: blood backs up into lungs right sided: blood backs up into organs

Question 38

what is biventricular failure

Answer 38

failure of one pump with eventually cause other pump to fail

Question 39

what is the difference between hypertrophy and dilation

Answer 39

hypertrophy: LV is stiff, can't pump as effectivelly dilation: wider, looser

Question 40

what does blocking the RAAS do for a patient in heart failure

Answer 40

it can prevent cardiac remodelling!

Question 41

what is the atrial kick

Answer 41

puts significant volume towards ventricular preload, essential for adequate ventricular filling (basically atria kick block into ventricles so they can fill)