Pathology last year Flashcards
Define hypertension
The persistent elevation of resting blood pressure above 140/90
Compare between benign and malignant hypertension
Benign HTN: gradual and moderate rise of blood pressure
Malignant HTN: rapid rise of blood pressure (exceeds 200/120)
Enumerate the etiological factors/ causes of essential hypertension
- Impaired renal sodium execration
- Increased vascular resistance
- Genetic factors (familial clustering of HTN)
- Environmental factors: stress, obesity and excess salt intake
List 6 causes of secondary hypertension?
- Renal artery stenosis
- Polycystic kidney
- Chronic pyelonephritis
- Hyperthyroidism
- Adrenocortical hyperfunction
- Coarctation of aorta
What are the pathological changes that accompany benign hypertension?
- Hyaline atherosclerosis
- Fibroelastic hyperplasia (elastosis)
- Concentric hypertrophy of the left ventricle
- Acceleration of atherosclerosis
- Benign nephrosclerosis
List the complications of benign hypertension
- Heart failure (cause of death)
- Cerebral hemorrhage
- Chronic renal failure
What are the pathological changes that accompany benign hypertension?
- fibrinoid necrosis
- hyperplastic atherosclerosis (onion-skin appearance)
- flea-bitten kidney
- hypertensive retinopathy (papilledema, retinal hemorrhage and exudate)
list the complications of malignant hypertension
- acute renal failure
- cerebral hemorrhage
- heart failure
Explain the types of benign hypertension
- Hyaline arteriolosclerosis:
-Generalized changes of small arteries and
arterioles. Homogeneous pink hyaline thickening of the
intima and media with narrowing of the
lumen. It results due to endothelial injury by
hemodynamic stress and leakage of plasma
components into the intima. - Fibroelastic hyperplasia (elastosis):
- Affects larger arteries.
-There is duplication of internal elastic lamina
with thickening of the media
Malignant Hypertension types
- Fibrinoid necrosis of the small arteries and arterioles
(Granular eosinophilic material in vessel wall). - Hyperplastic arteriolosclerosis:
onion-skin appearance of vessels due to
hyperplasia of smooth muscle cells and
connective tissue.
Define atherosclerosis
Atherosclerosis is the disease of blood vessels characterized by patchy intimal thickening as a result of lipid deposition, covered by a fibrous cap
Define Monckberg calcific medial sclerosis
Calcific deposits in muscular arteries, in patients older than 50 years. The lesion do not encroach on vascular lumen and are of no clinical significance
List the major risk factors of atherosclerosis
- Hyperlipidemia
- Hypertension
- Diabetes mellitus
- Smoking
mention the most suspectable sites for the formation of atheromatous plaques
- infrarenal vessels
- abdominal aorta
- coronary arteries
- popliteal arteries
- internal carotid arteries
- vessels of circle of Wills
Mention the effects & complications of atherosclerosis
- In medium sized arteries:
* Artery stenosis (leading to diminished tissue perfusion and ischemia)
* Complete arterial occlusion - In large arteries:
* Atheroembolism (can discharge debris into bloodstream, producing micro emboli)
* Thromboembolism
* Aneurysm formation (resulting in aneurysmal dilation and potential rupture)
Define aneurysm
Localized permanent arterial wall dilatation
Mention the causes of vessel wall weakness in aneurysm
- Congenital absence of the muscle wall and replacement by a fibrous tissue
- Loss of smooth muscle cells as in atherosclerosis and syphilitic aortitis
- Weakening of the arterial wall secondary to infection»_space; mycotic aneurysm
- Vasculitis
Mention types of aneurysms according to shape?
- Saccular aneurysm
- Fusiform aneurysm
- False aneurysm
Mention the types of aneurysms according to etiology?
- Congenital Aneurysm
- Atherosclerotic aneurysm in abdominal aorta, iliac arteries
- Syphilitic aneurysm
- Mycotic aneurysm
- Polyarteritis nodosa
Mention the complications of aneurysms?
- Rupture causing hemorrhage
- Mural thrombus formation with possible occlusion of ostia of vessels branching off the aorta
- Pressure on surrounding structures
What are the causes of dissecting aortic aneurysm?
- Hypertension > patients 40-60
- Marfan syndrome > young patients
Define Marfan syndrome
Congenital absence of fibrillin, which is a glycoprotein closely associated with elastic fibers. Occurs in young patients
Enumerate the etiological risk factors associated with varicose veins development
- Occupations with prolonged standing
- Obesity
- Pregnancy
What are the causes of congenital heart disease?
- Sporadic genetic abnormalities
- Environmental factors (alone or in combination with genetic factors)
* Gestational diabetes
* Teratogen exposure
* Nutritional factors
What are the main types of congenital heart anomalies?
- Malformations causing left-to-right shunt
- Malformations causing right-to-left-shunt
- Malformations causing an obstruction
Mention the types of ventricular septal defect
- Membranous
- Muscular (roger’s disease)
Mention the effects & the complications of the ventricular septal Defect
- May be isolated or associated with fallot tetralogy
- It may not be recognized until much later in life
- Causes significant left to right shunting, leading to early right ventricular hypertrophy and pulmonary hypertension, resulting in shunt reversal, cyanosis and death.
- Infective endocarditis opposite the shunt
List the complications of atrial septal defect
- Heart failure
- Paradoxical embolization
- Irreversible pulmonary hypertension
What are the abnormalities that accompany Fallot’s tetralogy?
- Pulmonary stenosis
- Right ventricular hypertrophy
- Ventricular septal defect
- Overriding of aorta
List the effects & complications of right to left shunts
- Cyanosis
- Secondary polycythemia
- Clubbing of fingers
- Infective endocarditis
Define Endocarditis
Inflammation of valvular & or mural endocardium. It may be infective or non-infective. Valvular endocarditis is characterized by vegetations, which are small platelet (pale) thrombi on valve
cusps.
Mention types of endocarditis
- Non infective endocarditis
- Infective endocarditis
Define Rheumatic fever
Rheumatic fever is an inflammatory, immune mediated multisystem disease affecting most importantly the heart in the form of a pancarditis (inflammation of all layers of heart). It occurs as a complication of streptococcal pharyngitis & tonsillitis.
Explain the pathogenesis of rheumatic fever
- Acute rheumatic fever results from abnormal host immune responses to group A streptococcal antigens that cross-react with host proteins, such abnormal response may be
genetically determined. - Antibodies and CD4+ T cells directed against streptococcal M protein recognize cardiac self-
antigens. - Antibody binding can activate complement, as well as recruit Fc-Receptor bearing cells (neutrophils and macrophages).
- Cytokine production by the stimulated T cells leads to macrophage activation
- Damage to heart tissue may thus be caused by a combination of antibody and T cell-
mediated reactions.
Describe the morphology of rheumatic fever myocarditis.
a) Pericardium: Fibrinous pericarditis (Fibrin deposited between the visceral and parietal layers gives the appearance of bread & butter pericarditis)
b) Myocardium: The distinctive lesions of rheumatic fever is called Aschoff bodies.
Gross appearance: 1-2 mm grey nodules in myocardium
Microscopic: Aschoff bodies are seen in the myocardial interstitial tissue, in a paravascular location. They consist of foci of fibrinoid degeneration surrounded by T lymphocytes, plasma cells, and plump activated macrophages called Anitschkow cells or caterpillar cells, which may
be multinucleated.
c) Endocardium (endocarditis): Valvular endocardium: The mitral valve is the most commonly affected. This is followed in frequency by the aortic and tricuspid, rarely the pulmonary valve.
List 6 extracardiac manifestations of rheumatic fever
- Fleeting arthritis
- Skin rash
- Subcutaneous nodules
- Rheumatic chorea
- Fibrinous pleurisy or peritonitis
- Rheumatic pneumonitis
- Rheumatic arteritis or hypersensitivity angiitis
Compare between acute infective endocarditis and Subacute infective endocarditis
Causes: by infection of heart value by highly virulent organism that causes necrosis and destructive lesions.
Complications: fever, chills, weakness, septic infractions
Subacute:
causes: occurs in bacteremia states where organism has low virulence and non-pyogenic
complications: fever, cerebral infarction, kidney infraction, splenic infarction
List 6 effects of mitral stenosis
- Chronic venous congestion of lung
- Left atrial thrombosis
- Left atrial hypertrophy and dilatation
- Arrythmias esp. atrial fibrillation
- Pulmonary hypertension»_space; right ventricular hypertrophy
List 4 causes of mitral incompetence
- Chronic rheumatic heart disease
- Healing of subacute infective endocarditis
- Dilatation of mitral ring 2ry to Lt. Ventricular dilatation
- Rupture of papillary muscle in recent infarction
List the effects of mitral incompetence
- Dilated left atrium
- Chronic venous congestion
- Heart failure
List 4 causes of aortic stenosis
- Rheumatic heart disease
- Healed subacute infective endocarditis
- Congenital aortic stenosis
- Senile calcific aortic stenosis
List 4 causes of pulmonary stenosis
- Congenital
- Healed subacute infective endocarditis
- Chronic rheumatic heart disease
- Carcinoid syndrome
List 3 causes of tricuspid stenosis
- Chronic rhematic valvulitis
- Healed subacute infective endocarditis
- Carcinoid syndrome
List causes of aortic incompetence
- Rheumatic heart disease
- Syphilitic aortitis
- Marfan syndrome
- Infective endocarditis
Define ischemic heart disease
A group of syndromes resulting from myocardial ischemia, imbalance between myocardial supply and cardiac demand for oxygenated blood
Mention the causes of ischemic heart disease
- Atherosclerosis (in 90% of cases)
- Other causes include:
* Coronary emboli
* Coronary vessel inflammation
* Vascular spasm
* Increased oxygen demand
Mention 4 clinical syndromes associated with IHD
- Myocardial infarction
- Angina pectoris
- Chronic IHD
- Sudden cardiac death
Mention sites of myocardial infarction
- Anterior infarction»_space; occlusion of left anterior descending artery (40-50% most common)
- Lateral infarction»_space; occlusion of the circumflex coronary
- Posterior infarction»_space; occlusion of the posterior descending arterty
What are the patterns of myocardial infarction?
- Transmural infarction
- Subendocardial infarction
Mention 6 complications of myocardial infarction
- Contractile dysfunction and heart failure
- Arrythmias
- Cardiac rupture
- Pericarditis
- Mural thrombosis
- Papillary muscle dysfunctio
List 6 causes of myocarditis
- Acute rheumatic carditis
- Viral infections
- Bacterial infections
- Parasitic infection
- Drugs
- Ionizing radiation
Define cardiomyopathy & list their types
Cardiomyopathies are a heterogeneous group of myocardial diseases associated with mechanical and/or electrical dysfunction of the heart
Their types:
1. Dilated cardiomyopathy (DCM) Most common type
2. Hypertrophic cardiomyopathy
3. Restrictive cardiomyopathy
Define pericarditis
Inflammatory reaction involving the visceral and/or the parietal pericardial layers
List 6 causes of pericarditis
- Rheumatic fever
- Viral
- Uremia
- Staphylococci and streptococci
- Surgery
- Trauma
List types of pericarditis
- fibrinous pericarditis
- suppurative
- Hemorrhagic
- Tuberculous
- Constrictive
- Adherent-mediastino-pericarditis
Define cardiac tamponade
Blood clotting suddenly and in large quantities in the pericardial sac, resulting in sudden death. It occurs in rupture myocardial infarction, rupture aortic aneurysm, ventricular aneurysm
Define heart failure
A condition where the cardiac output is insufficient to meet the metabolic demands of the tissues
List 3 causes of left sided heart failure
- Ischemic heart disease
- Systemic hypertension
- Valvular heart disease
List 3 causes of right sided heart failure
- Consequence of left side failure
- Mitral stenosis
- Cor pulmonale
What are the consequences of right and left heart failure
- Left heart failure: pulmonary congestion
- Right sided heart failure produces systemic venous congestion and liver enlargement
List 4 tumors of the heart
- Left atrial myxoma
- Rhabdomyoma
- Rhabdomyosarcoma
- Metastasis
List the complications of varicose veins
- Pain, congestion, edema and stasis dermatitis
- Chronic varicose ulcer (poor wound healing and superadded infection)
Mention the types & causes of vasculitis
- Infectious vasculitis:
* Bacterial or fungal infections of arterial wall
* Syphilitic aortitis - Non-infectious vasculitis:
* Hypersensitivity vasculitis
* buerger’s disease
Define thrombangitis obliterans
A segmental, inflammatory disease that most commonly affects the tibial and radial arteries, adjacent veins, and nerves (neurovascular bundle). It occurs almost exclusively in heavy
smokers
Give the pathogenesis of atherosclerosis
a) Hyperlipidemia, hypertension, smoking and hemodynamic forces cause endothelial injury. The endothelial injury leads to increased permeability to LDL, which accumulates in the intima.
b) Platelets adhere to the endothelium, also monocytes adhere to the endothelium and migrate into the intima and transform to macrophages.
c) Endothelial cells as well as monocytes release oxygen free radicals which cause oxidation of soluble LDL to insoluble oxidized LDL. Insoluble LDL and cholesterol crystals are taken up by macrophages which change to foam cells.
d) Under the effect of platelet derived growth factors, smooth muscle cells from the media migrate to the intima and proliferate. They secrete extracellular matrix (ECM) namely collagen.
e) T cells are recruited to the intima, are activated and produce inflammatory cytokines which stimulate macrophages, endothelial cells and smooth muscle cells
