Cardiovascular Flashcards
Risk factors for atherosclerosis
HTN HLD DM Smoking FHx Sedentary lifestyle and poor diet
Atherosclerosis role in AAA
a main risk factor (smoking biggest risk factor)
Plaque compresses underlying media -> problem with nutrient and waste diffusion
- > degeneration and necrosis of media
- > arterial wall weakness
Hyperhomocysteinemia clinical significance and treatment
risk factor for CVA, PVD, coronary heart dz
Tx: B6, B12, folic acid
Pathogenesis of atherosclerosis
- endothelial dysfunction (caused by HTN, HLD, DM, Smoking) leads to increased vascular permeability, leukocyte adhesion, and thrombosis
- Accumulation of lipoproteins - in vessel wall, mostly LDL
- Monocyte adhesion to the endothelium: migration of the monocytes into the intima and then transformation of these cells into macrophages and foam cells
- Factor release: activated platelets, macrophages, inflammatory mediators, cytokines
- Smooth muscle cell proliferation: migraiton of sm.m. cells into intima, deposition of elastin and collagen
- Lipid accumulation occurs extracelularly and within macrophages and smooth muscle cells -> bulging atherosclerotic plaque
Clinical presentation of atherosclerosis
most asx
Angina Claudication of LE Stroke sxs HTN retinal changes
Diagnostic tests for atherosclerosis
Exercise stress test - best initial test Nuclear stress test Stress test with echo Pharmacologic stress test PET myocardial imaging test Coronary angiogram - gold standard Ankle brachial pressure index Carotid U/S
Exercise stress test in atherosclerosis
best initial test to assess stable angina or worsening SOB with exertion or fatigue with exertion
Positive: CP, dizziness, claudication, decreased BP, ST changes
Nuclear stress test in atherosclerosis
Test to assess myocardial profusion
Stress test with Echo in atherosclerosis
assess wall motion abnormalities
Pharmacologic stress test in atherosclerosis
uses cardiac inotrope/chronotrope (dobutamine) or vasodilator (adenosine or dipyridamole) in place of exercise
caution with vasodilators in asthmatics and hypotensive patients
Positron emission tomography (PET) myocardial imaging in atherosclerosis
assess heart perfusion defects - lights up with adequate perfusion, black if not perfusing
Coronary angiogram in atherosclerosis
gold standard test
Assess degree of coronary artery occlusion - more invasive
Ankle brachial pressure index
Pt supine, ankle BP/brachial BP
assess peripheral artery disease
abnormal if less than 0.9 -> stress test or angiogram
Carotid ultrasound in atherosclerosis
assess carotid stenosis leading to TIA or stroke
Treatment of atherosclerosis
Stop tobacco use Normalize BP Control hyperglycemia Control hypercholesterolemia Low-fat diet exercise
Chylomicrons
lipoprotiens absorbed from gut travel to liver
VLDL
produced by liver, high in TGs
can become IDL and LDL
HDL
produced by liver
take up cholesterol deposited by LDL particles
LDL
high in cholesterol
made from VLDL
taken up into cells by endocytosis - part of atherogenesis
Secondary causes of hypercholesterolemia
T2DM Excess etOH Primary biliary cholangitis CKD Hypothyroidism Medications: oral estrogens, thiazide diruetics, B-blockers, atypical antipsychotics (clozapine, olanzapine), protease inhibitors
Xanthoma
deposits of lipid in tendons and under skin
Xanthelasma
deposits of lipid around eyes
Arcus senilis
deposits of lipids in the periphery of the corneas
Treatment of hypercholesterolemia
Goal: reduce risk of atherosclerosis and pancreatitis (TGs)
Lifestyle modifications: Wt loss aerobic exercise diet smoking cessation