Huber 1 Flashcards
Define Arteriosclerosis and what does it affect?
- Arterial wall thickening and loss of elasticity, aka “hardening of the arteries”
- Small arteries and arterioles
General patterns of Arteriosclerosis
- Hyaline and Hyperplastic Arteriosclerosis
- Monckeberg Medial Sclerosis
- Atherosclerosis
Hyaline and Hyperplastic Arteriosclerosis is characteristic of what?
Hypertension
Describe Monckeberg Medial Sclerosis
- Calcific deposits in muscular arteries in individuals > 50 years of age
- Possible metaplastic change into bone
- Lesions do not encroach on the vessel lumen and are typically of no significance
Atherosclerosis is characterized by intimal lesions called ____ that protrude into vessel lumens. Describe the lesion and its effects.
- Atheromas
- Raised lesion with a soft, yellow, grumous core of lipids (cholesterol and cholesterol esters) covered by a white fibrous cap
- Obstruct blood flow, rupture results in vessel thrombosis, may weaken the underlying media resulting in aneurysm formation
Atherosclerosis is characteristic for which disease?
Thrombotic disease (e.g. Ischemic heart disease)
Non-modifiable risk factors
- Increasing age - MI risk increase 5x b/w 40-60
- Family history - Most significant, multifactorial
- Male gender - premenopausal at lower risk then rises significantly after
- Genetic abnormalities - Minor contributor
Modifiable risk factors
- Hyperlipidemia - major independent factor
- Hypertension - major independent factor, increases IHD by 60%
- Cigarette smoking - well established factor, doubles IHD death rate
- Diabetes mellitus - well established factor, doubles risk of IHD, induces hypercholesterolemia
What are the differences between HDL and LDL?
- LDL delivers cholesterol to the peripheral tissues
- HDL transport cholesterol from tissues to liver for excretion in bile
Describe actions that reduce and induce cholesterol load
- Low cholesterol diet, polyunsaturated fats, omega-3 fatty acids, exercise, and moderate ethanol consumption reduce cholesterol load
- Obesity, smoking, and trans-unsaturated fats adversely affect cholesterol profile
Other Risk Factors
- Inflammation
- Hyperhomocystinemia : increased risk of CAD, peripheral vascular disease, stroke, and venous thrombosis
- Metabolic syndrome
- Lipoprotein (a)
- Factors affecting hemostasis
- Lack of exercise, competitive, stressful lifesytle, obesity
Describe the role of Inflammation as a risk factor and how it is detected.
- Present at all stages of atherogenesis
- Numerous inflammatory markers
-
C-reactive protein (CRP) is one of the most sensitive and is predictive risk of:
- MI/sudden cardiac death
- Stroke
- Peripheral artery disease
What is the Response-to-Injury Hypothesis?
A chronic inflammatory and healing response of the arterial wall to endothelial injury. Lesion progression occurs through the interaction of modified lipoproteins, monocyte-derived macrophages, and T lymphocytes ith the normal cellular constituents of the arterial wall.
Describe the five steps of Pathogenesis
- Chronic endothelial injury + Risk factors
- Endothelial dysfunction: Increased permeability, leukocyte adhesion, monocyte adhesion and emigration
- Macrophage activation and smooth muscle recruitment to intima
- Macrophages and smooth muscle cells engulf lipid
- Smooth muscle proliferation, collagen and other ECM deposition, extracellular lipid
What is the role of infection in Pathogenesis?
- Topic of ongoing debate
- Multiple infectious agents have been detected in atherosclerotic plaques
- Association/causality (coindicence? potentiators of response-to-injury hyposthesis?)
