What is atherosclerosis?
-a form of arteriosclerosis (abnormal thickening and hardening of vessel walls)
-characterized by soft deposits of intra-arterial fat and fibrin in the vessel walls that harden over time
-not a single disease but a pathologic process that leads to poor ou
What is the pathophysiology behind atherosclerosis?
1. injury occurs to the endothelial cells
2. injured cells become inflamed and cannot make normal amount of antithrombic acid and vasodilating cytokines (artery cannot dilate)
3. macrophages adhere to injured site and release inflammatory cytokines (ex: i
What are some causes of injury to endothelial cells (causing atherosclerosis)?
-smoking
-hypertension
-diabetes
-high LDL
-low HDL
-hyperhomocysteinemia (large amount of homocysteine, an amino acid, in the blood)
-elevated C-reactive protein
-increased serum fibrinogen
-insulin resistance
-oxidative stress
-infection
-periodontal di
What are the clinical manifestations of atherosclerosis?
-signs and symptoms that result from inadequate perfusion of tissues because of obstruction of the vessels that supply them
-partial vessel obstruction can lead to transient ischemic events
-as lesion becomes complicated, increasing obstruction may result
What is the primary goal in the management of artherosclerosis?
to restore adequate blood flow to the affected tissues
What are the risk factors for atherosclerosis?
-diabetes
-smoking (nicotine is a vasoconstrictor)
-hypertension
-cholesterol
-sedentary lifestyle
-obesity
-family history
-age (even children can have plaque)
-gender (women are more protected before menopause because of hormone regulation)
What are some major diseases caused by atherosclerosis?
-peripheral vascular disease
-stroke
-heart failure
-sudden cardiac death
-myocardial infarction
-angina pectoris
What are categorized as non-modifiable risk factors vs. modifiable risk factors?
non-modifiable = age, family history, sex, race
modifiable = lifestyle, diet, activity level
What is the definition of hypertension? What are the minimum values that classify as hypertensive?
consistent elevation of systemic arterial blood pressure; systolic?140, diastolic?90
What BP values classify as "normal'?
systolic<120
diastolic<80
What BP values classify as "prehypertension"?
systolic 120-139
diastolic 80-89
What BP values classify as "stage 1 hypertension"?
systolic 140-159
diastolic 90-99
What BP values classify as "stage 2 hypertension"?
systolic?160
diastolic ?100
Which is the most significant factor in causing target organ damage? Systolic or diastolic hypertension?
systolic hypertension
Prevalence for hypertension (decreases or increases) with age and is higher for (blacks or whites)?
increases with age; higher for blacks
What is primary hypertension?
-aka essential or idiopathic hypertension
-92%-95% of hypertensive individuals
-high blood pressure for which no medical cause can be found
What is malignant hypertension?
diastolic>140
What is secondary hypertension?
-caused by an underlying disorder that affects kidneys, arteries, heart, or endocrine system
-accounts for only 5%-8% of hypertension cases
-example: people who take steroids hold in water and thus there is an increase in BP
-caused by systemic disease pr
What are some groups of drugs to treat hypertension?
-beta blockers (androgenic receptors...reduce effects of norepinephrine and epinephrine)
-diuretics
-ACE inhibitors
-calcium channel blockers
What are the factors associated with primary hypertension?
(combination of genetic and environmental factors)
-renal sodium excretion
-insulin and insulin insensitivity
-activity of RAA system
-cell membrane sodium or calcium transport
-sympathetic response to neurogenic hormones
-inflammation
-endothelial dysfun
What is renin and why is it released?
-aka angiotensinogenase
-an enzyme that participates in the body's renin-angiotensin-aldosterone (RAA) system that mediates extracellular volume & arterial vasoconstriction
-released to compensate for decreased volume of blood (but kidneys can release too
What 2 things should you remember when thinking about blood pressure?
increased peripheral resistance and increased blood volume
Remember:
blood pressure = cardiac output x peripheral vascular resistance
(BP = CO x PVR)
What causes angiotensinogen to form angiotensin 1?
renin (released by decrease in perfusion and increase in SNS)
What is a shift in the pressure-natriuresis relationship?
-increased vascular volume is related to a decrease in renal excretion of salt
-people with hypertension tend to secrete less salt in their urine
What causes angiotensin 1 to form angiotensin 2?
ACE (ACE inhibitors do not allow angiotensin 1 to convert to angiotensin 2 and thus there is no increase in BP)
What manifestations does angiotensin 2 lead to ?
-increase ADH
-increase aldosterone
-increase vasoconstricion
-increase sodium retention
What is isolated systolic hypertension?
-sustained systolic BP is ? 140 and diastolic is below 90
-accounts for large proportion of HTN in individuals over 65
-strongly associated with cardiovascular and cerebrovascular events
-caused by increases in CO, total PVR, or both
An in crease in vasoconstriction leads to an ____ in pressure and thus an ____ in BP.
increase in pressure, increase in BP
What is complicated hypertension?
-chronic hypertensive damage to the walls of systemic blood vessels
-smooth muscle cells undergo hypertrophy and hyperplasia with fibrosis (development of excessive fibrous connective tissue) of the tunica intima and media
What are some cardiovascular complications of sustained hypertension?
-left ventricular hypertrophy
-angina pectoris
-CHF (left)
-CAD
-MI (myocardial infarction)
-sudden death
What is malignant hypertension?
-rapidly progressive hypertension
-diastolic pressure is >140
-can cause encephalopathy (cerebral edema that disrupts brain function and causes loss of consciousness)
What is pulse pressure?
-the difference between diastolic and systolic
-problems with a wide gap (high pulse pressure) are due to vessel walls
What are the EARLY manifestations of hypertension?
nothing except for elevated blood pressure ("silent disease")
What causes most clinical manifestations of hypertensive disease?
complications that damage organs and tissues outside the vascular system (evidence of heart disease, renal insufficiency, CNS dysfunction, impaired vision, impaired mobility, vascular occlusion, or edema can all be caused by sustained hypertension)
What is hydrostatic pressure?
pressure within vessels
What is left ventricular hypertrophy (LVH)?
-the thickening of the myocardium (muscle) of the left ventricle of the heart
-leads to decrease in cardiac output (it's just big, fails to contract properly) and fluid goes back from where it came
What are the clinical manifestations of left ventricular failure?
-fatigue (decreased RBC and oxygenation of tissues)
-cyanosis
-chest pain
-fluid buildup (long term backward effect)
-dyspnea (before you see peripheral edema)
What is dyspnea?
shortness of breath
What is the first treatment for hypertension?
prevention (lifestyle modifications)
What is necessary to diagnose someone with hypertension?
-measurement of BP on at least 2 separate occasions averaging 2 readings at least 2 minutes apart
-patient seated
-arm supported at heart level
-after 5 minutes of rest
-no smoking or caffeine intake in the previous 30 minutes
-24-hour BP monitoring (in s
What is orthostatic hypotension?
-aka postural hypotension
-decrease in both systolic (15 or more) and diastolic (10) blood pressure upon standing
-has to do with slow reflexes
-lack of normal blood pressure compensation in response to gravitational changes on the circulation
-patient ma
What is a complication of COPD?
peripheral edema
What is acute orthostatic hypotension?
normal regulatory mechanisms are sluggish because of:
-altered body chemistry
-drug action (antihypertensives, antidepressants)
-prolonged immobility caused by illness
-starvation
-physical exhaustion
-any condition that produces volume depletion (dehydra
What is chronic orthostatic hypotension?
-may be secondary to a specific disease (endocrine disorders, metabolic disorders, disease of PNS or CNS)
-may be idiopathic or primary
What are the three factors that form a pathophysiologic continuum that impairs the pumping ability of the heart by depriving the heart muscle of blood-born oxygen and nutrients?
-coronary artery disease
-myocardial ischemia
-myocardial infarction
What is peripheral artery disease (PAD)?
atherosclerotic disease of arteries that perfuse limbs, especially the lower extremities
What does CAD result from?
any vascular disorder that narrows or occludes coronary arteries
What is myocardial ischemia?
-local, temporary deprivation of the coronary blood supply (is reversible)
-develops if the flow or oxygen content of coronary blood is insufficient to meet the metabolic demands of myocardial cells (demand is higher than supply)
What is stable angina?
-chest pain lasting 3-5 minutes
-no permanent change or damage results
-can anticipate when next pain will occur
What is the most common caused of decreased coronary blood flow and resultant myocardial ischemia?
formation of atherosclerosic plaques in the coronary circulation: "unstable" plaques are prone to ulceration or rupture (results on platelet adhesion and thrombus formation)
What is prinzemetal angina?
-attributable to transient ischemia
-occurs unpredictably and often at rest
-vasospasm of arteries; does not have to involve atherosclerosis
-increased calcium flux in arterial smooth muscle