12 - Cardiovascular Pathology III Flashcards
What is the estimated prevalence of hypertension in the US?
Over 70 million
How do you diagnose hypertension??
Greater than 139/89
Three consecutive readings at least one week apart
What populations are at greater risk of developing hypertension?
- Elderly (increases with age)
- African Americans
What can hypertension cause?
Hypertensive heart disease is the leading cause of illness and death from high blood pressure.
What are causes of secondary hypertension?
- Acute glomerulonephritis
- Chronic renal disease
- Polycystic disease
- Renal artery stenosis
- Adrenocortical hyperfunction (Cushing’s, primary aldosteroism)
- Pheochromocytoma
- Hyperthyroidism
- Pregnancy induce hypertension
- Increased intracranial pressure
- Sleep apnea
- Acute stress (surgery)
What are some curable causes of systemic hypertension?
- Cushing’s disease/syndrome
- Adrenal cortical adenoma
- Pheochromocytoma
- Renal artery stenosis
What is optimal blood pressure?
Less than 120/80
What is prehypertension
120-139/80-89
What is stage I hypertension?
140-159/90-99
What is stage II hypertension?
Greater than 160/100
What is a hypertensive crisis? AKA malignant hypertension
Greater than 180/120
Medical emergency ***
What are the long term effects of hypertension on the brain?
- Cerebrovascular accident (stroke)
- Hypertensive encephalopathy (confusion, headache, convulsion)
What are the long term effects of hypertension on the vessels?
Increased atherosclerosis
What are the long term effects of hypertension on the retina?
Hypertensive retinopathy
What are the long term effects of hypertension on the heart?
- Myocardial infarction (heart attack)
- Hypertensive cardiomyopathy
- Heart failure
What are the long term effects of hypertension on the kidneys?
- Hypertensive nephropathy
- Chronic renal failure
What would you actually see in hypertensive retinopathy?
- Cotton wool spots (retinal cells have come together)
- Exudates
- Hemorrhage
What will you see in hypertensive damage of the kidney?
HTN kidney
- Sclerosis of the kidney
- Intimal thickening
- Retraction of the surface
- Can eventually lead to chronic renal failure
What will you see in hypertensive damage to the vasculature?
- Buildup of hyaline
- Smooth muscle proliferation
What are you at risk for with malignant hypertension?
Intracranial hemorrhage
This is the very worst case
When BP levels are elevated in the long term, what are you at risk for?
- Left ventricular hypertrophy
- Accelerated coronary artery disease
- Cardiac arrhythmias
- Congestive heart failure
- Sudden cardiac death
Give a brief description of right and left sided heart disease
Systemic hypertension –> Left sided heart disease
Pulmonary hypertension –> Right sided heart disease (Cor pulmonale)
How high does BP have to be to cause left-sided heart failure?
Even mild hypertension (levels only slightly above 140/90 mm Hg), if sufficiently prolonged, induces left ventricular hypertrophy.
Is the whole or part of the left ventricle typically affected?
Left ventricular hypertrophy (usually concentric – involves the entire left ventricle) in the absence of other cardiovascular pathology
What types of cells will we see in left-sided heart failure tissue?
Box car appearance cells packed full of proteins
The cells are producing more proteins and things to deal with the hypertrophy
What causes right sided hypertension?
Pressue overlaod of the right ventricle
What are the characteristics of right-sided hypertension?
- Right ventricular hypertrophy
- Dilation
- Heart failure can develop
What is cor pulmonale?
When the pulmonary hypertension is due to lung disease, we call it cor pulmonale
What is the most common cause of right sided hypertension?
Lung disorders
Describe the effect of hypertensive heart disease on life expectancy
- Even moderate elevation of arterial pressure leads to shortened life expectancy.
- At severely high pressures, mean arterial pressures 50% or more above average, a person can expect to live no more than a few years unless appropriately treated.
- If you have an adverse event, you have an even higher chance of dying
What is valvular heart disease?
A condition that results in stenosis, insufficiency (regurgitation or incompetence) or both
What is stenosis?
Stenosis is the failure of a valve to open completely. Stenosis leads to pressure overload of the heart
What is insufficiency?
Insufficiency, in contrast, results from failure of a valve to close completely, thereby allowing reversed flow. Valvular insufficiency leads to volume overload of the heart.
Valve can’t close properly
What are the top four most frequent causes of valvular heart disease (VHD)?
1 - Aortic stenosis
2 - Aortic insuffiviency
3 - Mitral stenosis
4 - Mitral insufficiency
What is aortic stenosis?
calcification of anatomically normal and congenitally bicuspid aortic valves
What is aortic insufficiency?
dilation of the ascending aorta, usually related to hypertension and aging
What is mitral stenosis?
Mitral stenosis: rheumatic heart disease
What is mitral insufficiency?
myxomatous degeneration (mitral valve prolapse)
What are the major causes of acquired heart valve disease?
- Senile calcification, calcification of congenitally deformed valve, calcification of mitral ring
- Postinflammatory scarring (rheumatic heart disease)
- Mitral valve prolapse
- Rupture or dysfunction of papillary muscle, rupture of chordae tendineae
- Infective endocarditis (IV drug abuse)
- LV enlargement (dilated cardiomyopathy, myocarditis)
- Aortic Disease - (degenerative aortic dilation, Syphilitic aortitis, and Rheumatoid arthritis, reactive arthritis, aortitis)
- Marfan syndrome
What conditions lead to BOTH stenosis and regurgitation?
- Calcification of congenitally deformed valve (bicuspid)
- Postinflammatory scarring (rheumatic heart disease)
What conditions lead to ONLY stenosis?
- Senile calcific aortic stenosis
What conditions lead to ONLY regurgitation?
- Idiopathic (spontaneous)
- Infective endocarditis
- Degenerative aortic dilation (Syphilis, rheumatoid arthritis, Marfans, Ehlers-Danlos)
What do the clinical consequences of valvular heart disease depend on?
Depends on the valve involved, the degree of impairment, how fast it develops, and the rate and quality of compensatory mechanisms.
What is the MOST COMMON of all valvular abnormalities?
Calcific aortic stenosis
Why does calcific aortic stenosis usually develop?
Usually the consequence of age-associated “wear and tear” of either anatomically normal valves or congenitally bicuspid valves (∼1% of the population).
Describe the age at which the valves affected usually calcify
Senile calcific aortic stenosis occurs seventh to ninth decades of life, whereas stenotic bicuspid valves tend to present in patients 50 to 70 years of age.
What happens in aortic stenosis?
- Valve can’t open completely
- You get a jet stream coming out of the aorta
- Left ventricle has to do more work in order to get the blood out
What do we know about the development of calcific aortic stenosis?
Prior work attributed aortic valve calcification to wear and tear degeneration and dystrophic and passive accumulation of hydroxyapatite, the same calcium salt that is found in bone.
What have recent studies suggested about calcific aortic stenosis?
More recent studies suggest that chronic injury due to hyperlipidemia, hypertension, inflammation, and other factors implicated in atherosclerosis may have a role and perhaps even precede the calcification.
Is there fusion of the valves seen in calcific aortic stenosis?
No
Where do we see the calcification in calcific aortic stenosis?
Within the sinuses of Valsalva
What is the long-term effect of calcific aortic stenosis?
The left ventricular myocardium is exposed to progressively increasing pressure overload
as the stenosis gets worse resulting in LVH
What are the clinical features of calcific aortic stenosis?
- Left ventricular (pressure overload) hypertrophy.
- The hypertrophied myocardium tends to be ischemic (as a result of diminished microcirculatory perfusion, often complicated by coronary atherosclerosis), and angina pectoris may appear.
- Cardiac decompensation and CHF may ensue
What is the prognosis of calcific aortic stenosis?
50% with angina will die within 5 years and 50% with CHF will die within 2 years if the obstruction is not alleviated by surgical valve replacement.
Is medical therapy effective?
Medical therapy is ineffective in severe symptomatic aortic stenosis.
What is the prognosis of asymptomatic patients?
In contrast, asymptomatic patients with aortic stenosis generally have an excellent prognosis.
Is it common to get calcific stenosis on congenitally deformed valves?
Yes
Bicuspid aortic valves are responsible for approximately 50% of cases of aortic stenosis in adults. Usually uncomplicated early in life.
Late complications of BAV include aortic stenosis or regurgitation, infective endocarditis, and aortic dilation and/or dissection.
How common is aortic valve sclerosis?
- Incidence: 29% of adults over 65yo and increases with age.
- Leads to aortic valve stenosis in 2% of cases which warrants valve replacement.
- 1.5X risk of cardiovascular death
What is aortic valve insufficiency (AI)?
Leaking of the aortic valve of the heart that causes blood to flow in the reverse direction during ventricular diastole, from the aorta into the left ventricle.
What causes aortic valve insufficiency?
This results in aortic backflow and massive LVH with dilatation and LV failure.
What is the etiology of aortic valve insufficiency?
- Rheumatic
- Endocarditis
- Aortic root dilatation
- Degenerative aortic dilation
- Syphilis
- Rheumatiod Atheritis
- Reactive Atheritis
- Aortitis
- Marfan’s syndrome
- Ehlers-Danlos syndrome
A lot of this has to do with the aging population
What is rheumatic fever?
Multisystem inflammatory disease that occurs a few weeks after an episode of group A streptococcal pharyngitis 3% of infected patients.
What are the characteristics of rheumatic fever?
(1) migratory polyarthritis of the large joints
(2) pancarditis (affects ALL the tissues of the heart)
(3) subcutaneous nodules
(4) erythema marginatum of the skin
(5) Sydenham chorea, a neurologic disorder with involuntary rapid, jerky, purposeless movements
Describe sydenham chorea
Jerky movements that start during the course of the disease - See this in children
What is the Jones criteria for diagnosing rheumatic fever?
Two major symptoms or one major symptom and two minor symptoms
What are the major symptoms of rheumatic fever?
- Migratory polyarthritis
- Carditis
- Subcutaneous nodules
- Erythema marginatum
- Sydenham’s chorea
What are the minor symptoms of rheumatic fever?
- Fever
- Arthralgia: Joint pain without swelling
- Elevated ESR or CRP
- Leukocytosis
- Heart block
- Elevated Antistreptolysin O titer or DNAase
- Previous episode of rheumatic fever
What causes rheumatic fever?
An immune reaction to post-streptococcal (Gp A, β- hemolytic) pharyngitis
Describe the immune reaction
Antigenic mimicry between streptococcal antigens, mainly M-protein epitopes and human tissues, such as:
- Heart valves
- Myosin and tropomyosin
- Brain proteins
- Synovial tissue and cartilage
This has been proposed as the triggering factor leading to autoimmunity in individuals with genetic predisposition
What kind of immune response does this initiate?
FULL IMMUNE RESPONSE
- Humoral response AND…
- T cell response (with killer and other cells)
- You destroy the antigen, but also heart tissue, valvular tissue, skin, brain, joints, etc.
What part of the heart does the initial infection affect?
Initial infection can effect the whole heart resulting in a pancarditis.
- Pericarditis – fibrinous
- Myocarditis – with Aschoff bodies
- Endocarditis – inflammation of valves with verrucae, scarring, fibrosis and complications of rheumatic valve disease.
If the valves are affected by rheumatic heart disease, which most likely to be affected?
1 - Mitral
2 - Aortic
3 - Tricuspid
4 - Pulmonic
What is rheumatoid heart disease pancarditis?
Inflammation of the entire heart
This will be seen in ACUTE RHEUMATIC FEVER - This will not be seen way down the road
What are verrucae?
Warts
- Not destructive, but that’s where the inflammation starts
- If the inflammation continues, you get thickening of the valvular material
- Fusion of the commissures in late lesion AV in addition to sclerosis or calcification
What does mitral valve stenosis look like in rheumatoid heart disease?
Fish mouth appearance
