Pathology Of The Heart Flashcards
What is CCF
Heart is unable to maintain an output sufficient for the metabolic requirements of the tissues and organs of the body.
•It can appear as the end stage of many forms of chronic heart disease
What are some causes of CCF
A) Loss of cardiac myocytes
•1) Myocardiac infarction
•2) Myocarditis e.g chaga’s disease
•3) Toxic damage e.g diphtheritic myocarditis
•B) Impaired contractility
•1) Amyloidosis
• 2) Beriberi
• 3) Hurler’s disease
C) Mechanical cardiac overload
• 1) Hypertension
• 2) Valvular heart disease
• 3) High output state eg:- thyrotoxicosis, anaemia, beriberi
• D) Impaired filling of the chambers
• 1) cardiac tamponade
• 2) constrictive pericarditis.
What are some causes of a left sided heart failure
Ischaemic heart disease
*Systemic hypertension( acute LVF)
*Rheumatic heart diseasei.e mitral &aortic valvular dx
*Myocardial diseases
What are some changes in organ mechanisms in a left cardiac failure
Lungs
Increased hydrostatic pressure
Pulmonary oedema and congestion
Heart failure cells
Brown induration of the lungs
Kidneys
Stimulation of the renin-angiotensin system
•Salt and water retention
•Acute tubular necrosis
•Pre-renal azotaemia
Brain
•Cerebral hypoperfusion
•Hypoxic symptoms e.g irritability, stupor & coma
What are some causes of right sided heart failure
•Cor pulmonale.
•Triscuspid & pulmonic valve lesions
•Congenital heart dx associated with left to right shunt
•Left heart failure.
What are some organ changes in a RSHF
Liver
Congestive hepatomegaly
*Central haemorrhagic necrosis
*Nutmeg appearance
*Cardiac sclerosis
*Cardiac cirrhosis
Spleen
Congestive splenomegaly ie reactive fibrosis
*Siderofibrotic nodules ( Ghandy-Gamna bodies)
Subcutaneous tissue
*Pitting pedal eodema
*Anasarca
Body cavities
*Pleural, pericardial & peritoneal effusion
What is hypertensive heart disease
Def. -Response of the heart to the increased demands induced by systemic or pulmonary hypertension
Systemic hypertensive heart disease
•LVH (usually concentric) in the absence of other vascular pathology
•History of hypertension
What is systemic hypertension
DEF—-sustained diastolic pressure >90mmHg or systolic > 140mmHg
•Classified as mild, moderate & severe.
What are the two causes of systemic hypertension
Essential hypertension 90-95%
Secondary hypertension 5- 10%
What are some genetic factors for essential hypertension
Genetic factors: Familial cluster,genetic defect in renal sodium excretion, etc
What are some environmental factors for essential hypertension
Stress, obesity, increased salt intake
Describe secondary hypertension
Renal diseases—acute GN,CGN,renal art. stenosis, renin producing tumours.
•Endocrine :- Cushing sydrome, phaechromocytoma, thyrotoxicosis
•Vascular :- Coartation of the aorta, vasculitis
•Neurogenic :- Psychogenic, increased intracranial pressure.
What is the pathogenesis of a secondary hypertension
BP=COXPR
•Increased PR —-pressure overload—myocardial hypertrophy
•Cardiomegaly & LV thickness
•Most pt.with hypertension has coronary atherosclerosis. This predisposes to ischaemic injury
What are some characteristics of a compensated heart
LVH (Concentric)
*No dilatation
*No valvular lesions
What are some characteristics of a decompensated heart
Cardiac dilatation
•Hypertrophy
•LV dilatation
•Cardiomegaly
What is cor pulmonale
DEF. RVH secondary to primary structural or functional lung disease.
It is also called RHF
What are some causes of cor pulmonale
Pulm hypertension
•COPD
•Intestitial lung dx
•Massive pulm. embolism
•Kypho-scoliosis
•Poliomyelitis
What is rheumatic fever
DEF An acute systemic febrile illness caused by Lancefield group A β-haemolytic streptococci.
•Pharyngitis 2-3weeks prior to the onset of symptoms.
•In the tropics skin infection may precede onset of symptoms
•Affects children between 6-16years(F>M)
•May occur in adults.
•Low Socio-economic group.
What are the major criteria for RF
Migratory poly arthritis & arthralgia of large joints
•Pan-carditis
•Erythema marginatum of the skin
•Sydenham’s chorea
•Subcutaneus nodules
What are the minor criteria for RF
Fever
•Increased ESR
•Increased ASO titre
•Leucocytosis
Jones criteria:-
•2major
•1major + 2 minor
What is RHD
Not directly caused by the organism
•Antibodies to strept. Cross-react with tissues of the heart, kidneys, etc.
•Commoner in blacks, and in Warmer climates
•Common among the poor.
•Usually a pan-carditis
Pericardium:-
•Fibrinous or Sero-fibrinous exudate
•Bread and butter pericarditis.
•Aschoff bodies not common
•Fibrin & mononuclear exudate
•May resolve completely or get organised, results in scarring adhesions without restriction.
Myocardium: Aschoff bodies are abundant in the perivascular space.
•Death may occur in acute R.F from CCF
•Chronic R.F —–fibrosis & lymphocytic infiltration.
What’s the morphology of an RHD
The diagnostic anatomic lesions of RHD is the Aschoff body.
•They are foci of fibrinoid necrosis surrounded by lymphocytes, macrophages, occasional plasma cells & plump activated histiocytes called Anitschkow cells or caterpillar cells because of the arrangement of the chromatin pattern of the nucleus
Describe Antischkow’s cells
Is pathognomonic of RH
•Also called caterpillar cells
•Are histiocytes with abundant cytoplasm and central round to ovoid nuclei in which the chromatin is disposed in a central, slender wavy ribbon
•Sometime the histiocytes are multinucleated
What is rheumatic endocarditis
Acute valvulitis; hyperaemia,oedema & thickening of the valves
•Verrucae : these are small friable vegetations deposited along the free edge of the cusps.
•Chronic valvulitis; there is progessive scarring & deformity of the valve leaflets.
•Mc Callum’s plaque are fibrous plaques seen on the subendocardium of the left atrium.
Fish- mouth” or “button hole” stenotic deformity may occur.
•Dystrophic calcification may occur in affected valves.
What are extra-cardiac lesion of RF
Subcutaneous nodules
•Polyarthritis( migratory)
•Pleural oedema and fibrinous exudates
•CNS Sydenham’s chorea characterized by rapid, irregular and purposeless movement ( basal ganglia haemorrhage,oedema,perivascular lymphocytic reaction)
What is a valvular heart disease
•Stenosis of the valve implies narrowing of the valve.
•Isolated mitral & aortic stenosis account for close to half of all valvular heart lesions.
•Stenotic valve impose volume overload as well as pressure overwork on the heart chamber involved.
Insufficiency or regurgitation occurs when a valve fails to close completely during systole.
•May occur as a result of intrinsic valvular dx or damage to the supporting structures
•Stenosis & regurgitation produce noisy movement of blood because of turbulence called cardiac murmur.
•Right heart valve disease is due to Carcinoid syndrome or congenital malformations.
What is IE
Invasion of the heart valve or the mural endocardium by infective agents.
2 FORMS.
•Acute – fatal fulminant infection. Occurs in a previously normal valve with highly virulent organism.
•Subacute. – smouldering, indolent illness. occurs in previously damaged valve.
•Distinction vague because of antibiotics.
Xterised by deposition of friable bulky, bacterial-laden (infective) vegetations on the heart valve.
Epidemiology &pathogenesis.
•Congenital heart dx e.g Tetralogy of Fallot,PDA.
•RHD
•Valvular defects.
Prosthetic valve
•Immunosuppresion eg HIV,drug induced
•Diabetes Mellitus
•Chronic alcoholics
•Intravenous drug abuse
•Commoner in males above 50yrs
Commoner in males.
•50-75% affect previously damaged valve
•Valves distorted by congenital malformations.
Factors predisposing to development of IE
•Seeding of blood with microbes.
•Haemodynamic disturbance occuring across deformed heart valve
Activation of clotting cascade
•Production of agglutinating antibodies leading to clumping of organism within the vegetation.
Heart—perforation of valve
•myocardial abscess
•suppurative pericarditis
•Congestive cardiac failure
•Fragmentation& embolization of septic vegetation to sites like brain, spleen, coronary arteries & kidneys
•Immune complex dx-focal GN
•OSTEOMYELITIS
What are the two types of non-infective endocarditis
Marantic endocarditis or non-bacteria thrombotic endocarditis
•Libman-Sacks dx or non-bacteria verrucous endocarditis.
What is marantic endocarditis
Debilitated and Cachetic patients
•Vegetations on line of closure of valves.
•Larger and softer than those of RF
•Frequency: mitral, aortic, tricuspid and pulmonary.
•Source of emboli to brain, lungs, kidney and spleen.
•Most common cause of coronary emboli.
What is Libman-Sacks endocarditis
Granular flat verrucae, both surfaces of valves.
•Mitral and Tricuspid valves commonly.
•Fibrinous, granular, sterile vegetations
•Valvulitis, immune complex mediated
•May appear in patients with SLE(50%).
•Usually does not deform the valves.
What are the types of pericarditis
Fibrinous
•Serous
•Serofibrinous
•Fibrinopurulent
•Purulent
•Haemorrhagic
•Cholesterol
•Granulomatous
•Adhesive
•Constrictive.