Norton - IHD

Question 1

IHD - general

Answer 1

imbalance - supply and demand for oxygenated blood for the heart

reduced nutrients, waste removal

Question 2

IHD is also called

Answer 2

CAD, coronary heart disease

Question 3

> 90% of IHD is caused by

Answer 3

reduced coronary blood flow due to atherosclerotic coronary arterial obstruction

Question 4

Clinical manifestation - IHD

Answer 4

angina pectoris
MI
Chronic IHD w/ HF
Sudden cardiac death

Question 5

1 cause of death of both men and women in US

Answer 5

IHD

Question 6

Pathogenesis IHD

Answer 6

demand > coronary perfusion

Question 7

What can increase the demand while perfusion is low

Answer 7

Fixed obstruction
acute plaque change

coronary thrombus
vasospasm

Question 8

obstruction needed to cause symptomatic ischemia with:

exercise

at rest

Answer 8

> 70% w/ exercise

> 90% at rest

Question 9

what can protect distal myocardium from ischemia

Answer 9

collateral

Question 10

triggering factors for acute plaque change

Answer 10

• adrenergic stimulation
• dynamic changes of the structure and composition of plaque
• moderately stenotic are most dangerous

Question 11

most dangerous trigger factor for acute plaque change

Answer 11

moderately stenotic

Question 12

Coronary thrombus can

Answer 12

• partial occlusion – eventually lead to total occlusion
• emolize
• activate SM growth-related signals

Question 13

Vasoconstriction is stimulated by

Answer 13

adrenergic agonist

platelet contents

Question 14

How does angina pectoris present?

Answer 14

Paroxysmal
Recurrent
Substernal/precordial chest discomfort - constricting, squeezing, choking, knifelike

lasts at most 15 min - no infarction

Question 15

what is angina pectoris due to

Answer 15

myocardial ischemia

Question 16

Stable angina - decreased coronary perfusion due to

Answer 16

fixed obstruction

Question 17

Unstable angina is due to

Answer 17

disruption of atherosclerotic plaque with superimposed partially occluding thrombus

Question 18

1 of the acute coronary syndromes

Answer 18

unstable angina

Question 19

Prinzmetal angina is not related to

Answer 19

physical activity
HR
BP

Question 20

2 of the acute coronary syndromes

Answer 20

MI

Question 21

Acute plaque disruption

Answer 21

• hemorrhage
• erosion/ulceration
• rupture or fissuring

Question 22

90% of transmural infarcts

Answer 22

acute plaque disruption – platelets adhere to exposed subendothelial collagen/necrotic plaque contents, release aggregators – vasospasms – other extrinsic coag pathway also gets activated – Thrombus quickly occludes lumen

Question 23

myocardial response to ischemia at ~ 1 sec

Answer 23

cessation of aerobic glycolysis

decreased creatine phosphate, ATP

Accumulate lactic acid

Question 24

when does loss of contractility occur

Answer 24

after 2 min

Question 25

when does injury to myocyte become irreversible?

Answer 25

20-40min

Question 26

microvascular injury occurs

Answer 26

after 1 hr

Question 27

_____ may occur even due to ischemia

Answer 27

arrhythmias

Question 28

Subendocardial infarct is NOT due to

Answer 28

plaque disruption | superimposed thrombus

Question 29

Subendocardial infarct is majorly due to

Answer 29

diffuse stenosing coronary atherosclerosis with reduction of blood flow

Question 30

Morphology of MI depends on

Answer 30

- Location, severity and rate of dev of coronary obstruction - size of area perfused by obstructed vessel - duration of occlusion - metabolic/oxygen demand - extent of collateral - coronary vasospasm - BP, HR, rhythm - Necrosis (complete in 6 hrs)

Question 31

Infarct modification by reperfusion

Answer 31

Thrombolysis Angioplasty w/ stent placement CABG

Question 32

Grafting of RCA LAD

Answer 32

RCA - saphenous vein | LAD - internal mammary artery

Question 33

Factors associated with poor prognosis (MI)

Answer 33

Advanced age female gender DM previous MI

Question 34

Consequence and complications of MI

Answer 34

Contractile dysfunction (htn, pulmonary vascular congestion, cardiogenic shock if severe) Arrhythmias Myocardial rupture Pericarditis right ventricular infarct Mural thrombus Ventricular aneurysm Papillary m. dysfunction Progressive late heart failure

Question 35

Most common to least common myocardial rupture

Answer 35

Ventricular free wall -- cardiac tamponade Intraventrucular septum -- L-R shunting Papillary m. -- severe mitral regurgitation

Question 36

What is a later complication of MI

Answer 36

ventricular aneurysm

Question 37

is rupture common with ventricular aneurysm?

Answer 37

no - scar tissue is strong

Question 38

Complications of MI depend on

Answer 38

infarct size, site, transmural extent

Question 39

Large transmural infarct

Answer 39

Cardiogenic shock Arrhythmias late CHF

Question 40

Anterior transmural infarct

Answer 40

``` Free-wall rupture expansion Mural thrombi aneurysm worse clinical course ```

Question 41

Inferior transmural infarct

Answer 41

conduction blocks | RV involvement

Question 42

Most important factors affecting prognosis after an MI

Answer 42

- quality of LV function | - extent of vascular obstruction perfusing viable myocardium

Question 43

Often elderly, ptns develop ________ due to ischemic myocardial damage

Answer 43

progressive HF

Question 44

Chronic ischemic heart dz

Answer 44

hypertrophy, dilation, stenosis of coronary, healed previous infarcts

Question 45

is prior sx or history necessary to present with CHF?

Answer 45

no

Question 46

Sudden Cardiac death

Answer 46

Unexpected death from cardiac causes - no symptomatic heart dz or early after the onset of sx (less than 1 hr)

Question 47

Sudden cardiac death is usually due to

Answer 47

IHD

Question 48

Other causes of Sudden cardiac death

Answer 48

- congenital - valvular issues (aortic) - myocarditis - cardiomyopathy

Question 49

Ultimate mechanism of Sudden cardiac death

Answer 49

lethal ARRHYTHMIA

Question 50

#3 of the acute coronary syndromes

Answer 50

Sudden cardiac death

Question 51

Morphology of sudden cardiac death

Answer 51

- coronary artery occlusion 75% in one or more of the three major vessels High grade stenosis

Question 52

Prognosis in survivors of sudden cardiac death is improved by

Answer 52

implanting automatic cardioverter-defibrillator

Question 53

The acute coronary syndromes:

Answer 53

unstable angina acute MI sudden cardiac death

Question 54

What do acute coronary syndromes share?

Answer 54

- common pathophys - | coronary atherosclerotic plaque disruption and assoc. intraluminal platelet-fibrin thrombus formation