Mod6 (ischemic heart disease)

Question 1

Ischemia

Answer 1

myocardial O2 demand exceeds the supply

Question 2

Ischemic heart disease

Answer 2

inability of atherosclerotic (blocked) arteries to supply heart under conditions of increased O2 consumption

Question 3

Myocardial O2 SUPPLY depends on:

Answer 3

quantity of O2 carried by RBCs (HB concentration, systemic oxygentation) AND Rate of Coronary Blood flow (perfusion pressure, vascular resistance, intrinsic regulations…)

Question 4

Myocardial O2 DEMAND depends on:

Answer 4

Ventricular wall stress, HR and Contractility

Question 5

Coronary arteriosclerosis

Answer 5

assoc with ischemia; focal narrowing of coronary artery by fixed plaque and abnormal vascular tone

Question 6

Atherosclerosis

Answer 6

distal vessels of coronary arteries dilate in response to increased metabolic demand; if artery is more than 90% blocked by stenosis; dilation is NOT adequate to prevent ischemia

Question 7

Collateral vessels

Answer 7

develop to compensate for coronary artery blockage; develop btw obstruction and non-obstruction

Question 8

Endothylial dysfunction

Answer 8

assoc with ischemia; an imbalance btw vasodilation and vasoconstriction; causes ischemia due to inappropriate vasoconstriction due to lack of nitric oxide release

Question 9

Non modifiable risk factors of atherosclerosis

Answer 9

age (worsen with age), gender (men are worse than women pre menopause), and family history

Question 10

Modifiable risk factors of atherosclerosis

Answer 10

SMOKING(affects LDL, displaces o2),HYPERTENSION risk is directly proportional to duration and severity), DYSLIPIDEMIA (high LDL levels in blood), DIABETES, ESTROGEN DEFICIENCY (E increase HDL and lowers LDL), INACTIVITY, OBESITY

Question 11

Angina Pectoris (5 types)

Answer 11

chest pain caused by imbalance btw myocardial O2 demands and its supply; usually triggered by exercise, emotion, physical stress; radiates to left side

Question 12

1. Stable angina

Answer 12

chronic, predictable pattern caused by exertion/emotional stress; from obstructive plaque

Question 13

2. Unstable angina

Answer 13

stable angina at increased frequency and duration of episodes; occurs at rest

Question 14

3. Variant Angina

Answer 14

random episodes, often at rest; due to spasm of artery extreme enough to induce ischemia at rest

Question 15

4. Silent ischemia (angina)

Answer 15

absence of noticeable discomfort (asymptomatic)

Question 16

5. Syndrome X (angina)

Answer 16

chest pain caused by ischemia w/o significant arteriosclerosis; from inadequate vasodilation

Question 17

Diagnosis of Chronic stable angina

Answer 17

angina is NOT a sharp/stabbing pain, lasts less than 10 min, but more than a few seconds, it diffuses (isn’t localized) and radiates to left side; will occur with increased O2 demand

Question 18

Nitroglycerine

Answer 18

venodilator that is used to relieve angina; dilates coronary vessels

Question 19

organic nitrates

Answer 19

relieve ischemia via vasodilation

Question 20

beta blockers

Answer 20

decrease myocardial O2 supply by decreasing ventricular contractility and HR

Question 21

Ca2+ channel blockers

Answer 21

decrease O2 demand (venodilation) and increase myocardial O2 supply (coronary dilation)

Question 22

Acute Coronary Syndrome (ACS)

Answer 22

sudden reduced blood flow to heart associated with rupture of an atherosclerotic plaque and partial or complete thrombosis of the infarct-related artery; clinically presents at STEMI, NSTEMI and UA (unstable angina)

Question 23

Partial block in ACS

Answer 23

causes UA and NSTEMI; where NSTEMI can cause necrosis

Question 24

Complete block in ACS

Answer 24

results in STEMI and large areas of necrosis

Question 25

Myocardial Infarction

Answer 25

result of inadequate O2 supply to heart causing necrosis