ASCVD Pathology Flashcards
what is Arteriosclerosis
Vascular disease manifested by thickening and inelasticity of arteries
what are the 3 patterns of arteriosclerosis
atherosclerosis (AS)
Monckeberg’s medial calcific sclerosis
arteriolosclerosis
what is Medial Calcific Sclerosis
Calcification of muscle wall (media) of arteries
May ossify
No narrowing of vessel lumen
Patients older than 50 years.
what are the two types of Arteriolosclerosis� and are associated with
Thickening and narrowing of vascular walls of small arteries and arterioles,Associated with hypertension and diabetes
what are the two types of Arteriolosclerosis
hyaline and hyperplastic
what is Atherosclerosis
Intimal fibrofatty plaques
narrow vascular lumen
weaken arterial wall (media)
what are the major targets of Atherosclerosis
aorta, coronary arteries, cerebral arteries
what is the epidemiology and risk factors of Atherosclerosis.
Responsible for half of all deaths in the western world
Ubiquitous in developed nations
Less common in Central and South America, Africa, Asia, Japan
Begins in early childhood
What has caused a reduction in Atherosclerosis
Life-style changes (diet, smoking, control of HTN)
Improved therapy for IHD
Prevention of recurrences
what are the constitutional RF for Atherosclerosis
Age 40 to 60 year olds have 5X incidence of MI
Sex (males have 5X death rate from IHD until menopause
same MI frequency by 7th to 8th decade)
Genetics (familial clustering of other risk factors
genetic defects (eg familial hypercholesterolemia)
what are the acquired risk factors for Atherosclerosis
Hyperlipidemia
Hypertension 160/95 has 5X risk IHD than < 140/90
Smoking 1ppd X years has 200% increase in death rate from IHD
Diabetes 2X incidence of MI, increased risk of stroke, 100X risk of gangrene
C-reactive protein
“Soft” risk factors`
What does C-Reactive protein tell us
Systemic marker of inflammation synthesized by liver
Level correlates with risk of IHD/MI, stroke, PVD, SCD
what reduces CRP
smoking cessation, weight loss, exercise, statins
what is the role of HDL
Reverse transport of cholesterol from cells/plaque to liver for excretion in bile
what elevated HDL
Exercise and ETOH
what reduces HDL
Obesity and smoking reduce HDL
True of False risk factors are not additive
TRUE
what are other RF for AS
Inadequate physical activity Type A personality Obesity Estrogen deficiency High carbohydrate diet Hardened (trans) unsaturated fat intake Chlamydia pneumoniae
what is Hyperhomocystinemia
Inborn error of metabolism resulting in high levels of circulating homocysteine
Can also be caused by low folate and vitamin B intake
Level correlates with CAD, PVD, stroke and venous thrombosis
what is Lipoprotein Lp (a)
Altered form of LDL (apolipoprotein B-100 of LDL linked to apolipoprotein A)
Correlation between increased lipoprotein Lp(a) and coronary and cerebral vascular disease
Response to Injury Hypothesis
Focal chronic endothelial “injury”
Endothelial dysfunction and monocyte adhesion/emigration
Smooth muscle cell emigration and macrophage activation
Macrophages and SMCs engulf lipid
Proliferation of SMCs, ECM deposition, extracellular lipid.
Cellular Events in AS
Endothelial injury Lipids Macrophages Smooth muscle cells Infection
Endothelial Injury
Endotoxin Hypoxia Smoking Viruses Immune reactions Homocysteine Hemodynamics Hypercholesterolemia
Hemodynamics
Shear stress and turbulent flow
plaques occur at branch points and posterior abdominal aorta
Lesion protected areas associated with induction of atheroprotective genes
Severity of AS correlates with total
LDL cholesterol levels
AHA classifications of lesions Type I - Type II - Type III - Type IV - Type V - Type VI -
Fatty dot Fatty streak Intermediate lesion Atheroma Fibroatheroma Complicated plaque
what is an Aneurysms
Abnormal dilatation of arteries/veins due to weakening of vessel wall
What is the most common cause of aortic aneurysms
Atherosclerotic Aneurysms
Ischemic Heart Disease
Also called coronary heart (artery) disease (most common cause is atherosclerosis)
Most common cause of death (1/3 of all deaths) in developed countries
Ischemic Heart Disease 4 syndromes
angina pectoris
sudden cardiac death
myocardial infarction
chronic IHD
Coronary Artery Thrombosis
Plaque rupture exposes thrombogenic lipids and subendothelial collagen
Complete occlusion results in AMI
Incomplete occlusion results in U/A or sudden death or microinfarcts downstream
other causes of IHD
Emboli from vegetations Vasculitis Systemic hypotension Systemic hypertension Valvulopathy
Angina Pectoris
Intermittent chest pain due to reversible myocardial ischemia
Three types of angina pectoris
stable angina
Prinzmetal’s or variant angia
unstable angina
Stable Angina
Episodic chest pain associated with exertion or stress
Chest pain is crushing, squeezing, may radiate to left arm
Fixed lesions > 75% vessel lumen
Relieved by rest, NTG (reduces preload and augments coronary blood flow)
Prinzmetal’s Angina
Also called variant angina
Chest pain occurs at rest or while sleeping
Vasospasm near plaque
Responds to vasodilators
Unstable Angina
Also called crescendo and preinfarction angina
Increasing frequency of chest pain
More intense and longer duration
Due to acute plaque change
Myocardial Infarction
Local ischemia leading to corresponding myocardial necrosis
Single most common cause of death in industrialized nations
Pathogenesis of MI
Coronary artery thrombosis most common cause of MI preexisting plaque disrupted Vasospasm Platelet aggregation Hypoperfusion
Infarct location
LAD (40 to 50%) - anterior/apical infarcts
RCA (30 to 40%) - posterior/basal infarcts
LCX (15 to 20%) - lateral
Complications of MI
Papillary muscle dysfunction Rupture Mural thrombi Acute pericarditis Ventricular aneurysm
Clinical Features of MI
Severe crushing substernal chest pain +/- radiate to neck, jaw, epigastrium, shoulder, left arm for hours to days unrelieved by NTG
