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Flashcards in Cardiovascualr System 2 Deck (71):
1

What is stenosis

Failure of a valve to open completely
This impedes the forward flow of blood

2

What is incompetent regurgitation

Failure of the valve to close completely
Allows the reverse flow of blood

3

What can valvular heart disease affect

Pure or mixed regurg or stenosis
Single or multiple valves

4

What is functional regurgitation

Valve becomes incompetent due to dilation of a ventricle

5

What does the clinical consequences of valvular heart disease depend on

Which valve
Degree of impairment
Rate of it's development
Rate and quality of compensatory mechanisms
Can go from being physiologically unimportant to severe and rapidly fatal

6

What causes valvular incompetence

Intrinsic disease of the valve cusps or damage to or distortion of the supporting structures
Aorta
Mitral valve annulus
Tendinous cords
Papillary muscle
Ventricular free wall
+/- underlying valve abnormality
ACUTE OR CHRONIC

7

Valvular stenosis
Acute or chronic

Is the valve abnormal in this

Usually chronic
Almost always has an underlying valve abnormality

8

Where can valvular calcification occur

Calcific aortic stenosis
Calcification of a congenitally bicuspid aortic valve
Mitral annular calcification

9

What are heart valves subjected to

High repetitive mechanical stress especially at hinge points of cusp/leaflet
40 million cycles a year
Substantial tissue deformation
Transvalvular pressure gradients - aortic 120mmHg mitral 80mmHg
Cumulative damage is complicated by dystrophic calcification

10

Causes and epidemiology of calcific aortic stenosis

Age related wear and tear calcification
Clinically apparent 70-80 yo
Calcification of bicuspid valve occurs earlier

11

Most common cause of mitral stenosis

Rheumatic heart disease

12

Most common cause of mitral incompetence

Floppy mitral valve
Myxomatous degeneration
Mitral valve prolapse

13

Most common cause of aortic stenosis

Calcification of normal and congenitally bicuspid aortic valves

14

Most common cause of aortic incompetence

Dilation of ascending aorta related to hypertension and age

15

Mitral regurgitation facts

Most common form of valvular heart disease in the industrialised world
One or both mitral leaflets enlarged, hooded, redundant so prolapsed back into atrium during systole
Usually incidental finding on examination - mitral valve prolapse
Very rarely - sudden death

16

What is rheumatic fever

Acute immunologically mediated multisystem inflammatory disease
Occurs a few weeks after group A beta haemolytic streptococcal pharyngitis
Thought to be a hypersensitivity reaction induced by group A streptococci
Features:
Migratory polyarthritis of large joints
Carditis
Subcutaneous nodules
Skin rash
Syndenham chorea - neurological disorder (purposeless movements)

17

What is rheumatic heart disease

Acute leads to pancarditis
Endocardium --> vegetations
Myocardium --> Aschoff bodies
Pericardium --> pericarditis
Reactivation with subsequent pharyngeal infections
--> cumulative damage

18

What is the most important complication of rheumatic fever

Chronic rheumatic heart disease
Characterised by
Deforming fibrotic valvular disease esp mitral stenosis
Fish mouth/button hole stenosis
Leaflet thickening, commissural fusion and shortening, thickening and fusion of chordea tendinea
Can cause permanent dysfunction
Most frequent cause of mitral stenosis
End stage of organisation of acute inflammatory damage

19

What is infective endocarditis

Serious infection
Colonisation/ invasion of the heart valves
Formation of friable bulky vegetations - composed of thrombotic debris and organisms
Often underlying tissue destruction
Most cases are BACTERIAL

20

Infective endocarditis types

Acute and subacute.

21

Characteristics of acute infective endocarditis

High virulence
Valve previously normal
Acute onset
50% mortality days to weeks
Lesion is necrotising, ulcerative and invasive

22

Characteristics of subacute infective endocarditis

Low virulence
Insidious onset
Most recover weeks to months
Less destructive

23

What causes a predisposition to infective endocarditis

Abnormal valve -
Floppy mitral valve
Degenerative calcific valvular stenosis
Bicuspid aortic valve
Artificial valve
(Vascular graft)
Host factors -
Immunosuppression - neutropenia, immunodeficiency, therapeutic

Diabetes
Alcohol
IV drug use

24

What are the organisms involved in infective endocarditis

Alpha-haemolytic strep - abnormal valve 50-60%, subacute
Staph aureus (skin) high virulence, normal valve, IV drug users
Mouth commensals - most of rest
Staph epidermidis - prosthetic valves

25

How does the person get infected

Dental or surgical procedure
Dirty needle
Trivial injury

26

What should be done for those at risk

Prophylactic antibiotics

27

Morphology of infective endocarditis

Aortic and mitral valve most commonly affected
Tricuspid valve in IV drug users
Bulky friable vegetation
May involve more this one valve

28

Complications of infective endocarditis

Myocardial abscess
Valve rupture/perforation
Systemic emboli- L sided body -kidney
R sided - lungs
Septic emboli
Immune complexes

29

What is non bacterial thrombotic endocarditis

Deposition of fibrin/platelet thrombi on valve leaflets -SMALL
Occur on either side of the heart
Occurs on a previously normal valve
Sterile
Non-destructive
Clinical importance = emboli
Occurs in hypercoagulable state -
Disseminated intravascular coagulation
Cancer sepsis

30

What are the types of artificial valves

Mechanical
Bioprostheses
- homografts
- chemically treated animal (porcine) valves

31

Complications of artificial valves

Thromboembolic - need long term coagulation
Infective endocarditis
Structural deterioration - esp bioprostheses

32

What is a cardiomyopathy

Heart disease resulting from a primary abnormality in the myocardium

33

What are the causes of a cardiomyopathy

Inflammatory
Immunological
Systemic metabolic disorders
Muscular dystrophies
Genetic abnormalities of the cardiac myocytes
- cardiac energy metabolism
- structural and contractile proteins
Idiopathic

34

What are the 3 clinical pictures of cardiomyopathy

Dilated cardiomyopathy DCM 90%
Hypertrophic cardiomyopathy HCM
Restrictive cardiomyopathy least common
Within each group - spectrum of diversity and overlap of features between groups
Each pattern can be idiopathic , specific identifiable cause
Or secondary to extramyocardial disease
Diagnoses - endomyocardial biopsies of RV

35

What is dilated cardiomyopathy characterised by

Progressive -
Cardiac hypertrophy
Dilation
Contractile Dysfunction
Leads to congestive cardiac failure

36

Causes of dilated cardiomyopathy

Most idiopathic
Alcohol
Peripartum
Genetic (ox phos, beta ox FFA, dystrophin)
Myocarditis
Haemochromatosis
Chronic anaemia
Drugs - doxorubicin, adriamycin
Sarcoidosis

37

What is the morphology of dilated cardiomyopathy

Gross
Heavy heart 2-3x normal
Large flabby
Dilation in all chambers
Mural thrombi common - thromboemboli
+/- secondary mitral/tricuspid regurg
Normal coronary arteries
Histology -
Non specific
Hypertrophied fibres
Attentuated/ stretched fibres
Interstitial and endocardial fibrosis

38

Clinical features of dilated cardiomyopathy

any age 20-60
Slowly progressive CCF
But can be sudden compensated --> decompensated functional state
EF 25%
50% mortality in 2 years
Death - progressive CCF
- arrhythmia
Embolism
Treatment cardiac transplant

39

What is hypertrophic cardiomyopathy characterised by

Myocardial hypertrophy
Abnormal diastolic filling
1/3 intermittent left ventricular outflow obstruction
Heavy muscular hyper contracting heart

40

What is the gross morphology of hypertrophic cardiomyopathy

Massive myocardial hypertrophy
No ventricular disease
Asymmetric septal hypertrophy (10% symmetric)

41

What is the histology of hypertrophic cardiomyopathy

Extensive myocyte hypertrophy
Myocyte disarray
Interstitial fibrosis

42

What is the pathogenesis of hypertrophic cardiomyopathy

50% genetic
50% sporadic
Genetic autosomal dominant with variable penetrance
Many difference mutations in 4 genes that encode contractile proteins (sarcomeres)
1) B- myosin heavy chain
2) cardiac troponin T
3) alpha - tropomyosin
4) myosin binding protein C

43

Clinical features of hypertrophic cardiomyopathy

Basic abnormality - Dec chamber size + poor compliance + Dec stroke volume

Clinical problems
Angina
AF
Cardiac failure
Ventricular arrythmias
Sudden death

44

What is restrictive cardiomyopathy

Primary Dec in ventricular compliance -> impaired ventricular filling

45

What are the causes of restrictive cardiomyopathy

Idiopathic
Radiation fibrosis
Amyloidosis
Sarcoidosis
Metastatic tumour
Products of inborn errors of metabolism
Endomyocardial fibrosis (children in tropical areas)
Endocardial fibroelastosis (young children)
Many of these can be diagnosed by endomyocardial biopsy

46

Features of restrictive cardiomyopathy

Normal sized ventricles
Normal sized ventricular chambers
Both atria dilated
Firm myocardium

47

What is myocarditis

Inflammatory process of the myocardium which results in injury to the cardiac myocytes

48

Causes of myocarditis

Infection - esp viruses most common
Immune - post viral, post strep (rheumatic fever), SLE, drug hypersensitivity, transplant rejection
Unknown sarcoidosis

49

Clinical features of myocarditis

Asymptomatic could lead to dilated cardiac myopathy years later
Or could lead to arrythmias, acute heart failure, sudden death

50

Types of Pericardial disease

Pericardial effusion- fluid variety of compositions e.g. Transudate and exudate
Haemopericardium- blood
Purulent pericarditis - pus

51

What is pericardial disease called when it is large and rapidly developing

Cardiac tamponade

52

How can a haemopericardium form

Ruptured MI
Traumatic perforation
Ruptured aortic dissection

53

What is pericarditis

Pericardial inflammation
Secondary to cardiac disease , thoracic or systemic disorders, or metastasis from distant site

54

Causes of pericarditis

Infection
Virus
Bacteria
TB
Fungi
Immune mediated :
Rheumatic fever
SLE
Scleroderma
Post MI dressier syndrome
Drug hypersensitivity
Miscellaneous:
MI
Uraemia
Post cardiac surgery.
Neoplasia
Trauma
Radiation

55

What are the types of pericarditis

Serous
Fibrinous
Purulent/suppurative
Haemorrhaging
Caseous

56

What are the outcomes of pericarditis

Reabsorbed
Resolve
Organise -> obliterate pericardial space
+/- constructive pericarditis = heart is surrounded by dense fibrous scar that limits diastolic expansion of the heart and restricts cardiac output

57

What is a neoplasm of the heart called and how common are they

Myxoma
Rare
5% of people dying from cancer
Most commonly a primary tumour

58

Where is the most likely location of a myxoma

90% are located in the atria -most left
Called an atrial myxoma

59

What is the gross morphology and what problems can it cause

Sessile or pedunculated

Cause
Half valve obstruction
Injury to the valve
Embolisation

60

What is congenital heart disease

Abnormalities of the heart or great vessels present at birth

61

What are the 3 main categories of congenital heart disease

1) left to right shunt
2) right to left shunt
3) obstructions

62

What is a shunt

Abnormal connection between chambers or blood vessels
Blood flows from high to low pressure

63

What is a right to left shunt and what are the consequences of this

Blood shunted from the pulmonary to the systemic circulation
Therefore the blood is less oxygenated -> cyanosis
Cyanosis congenital heart disease

64

Conditions associated with right to left shunts

Tetralogy of fallot - most common
Transposition of the the great arteries
Persistent truncus arteriosus
Tricuspid atresia
Total anomalous pulmonary venous connection
Can get paradoxical embolus
Veins bypass lungs to systemic circulation

65

What is a left to right shunt

Blood shunted from systemic to pulmonary army circulation

66

Consequences of a left to right shunt

Increased pulmonary blood flow
-> pulmonary hypertension.
Reversible initially but need early treatment
With time -> reversal of shunt (high to low pressure)
-> late cyanosis (eisenmengers syndrome)
ASD
VSD- most common
PDA
AV septal defect

67

What cause obstruction

Chamber
Valve blood
vessel
Abnormal narrowing

68

What is vasculitis

Inflammation of wall of blood vessel

69

Cause of vasculitis

Immune :
Immune complex
Antineutrophil cytoplasmic antibodies
Direct antibody mediated
Cell mediated
Inflammatory bowel disease
Paraneoplastic
Infectious:
Unknown
Giant cell (temporal) arteritis- most common
Takayasu arteritis
Polyarteritis nodosum

70

Consequences of vasculitis

affect specific blood vessels
Different patterns
Small vessel - skin - rash
Kidney glomerulonephritis

71

Aetiology of vasculitis

Infection - acute or chronic, bacterial viral fungal
Neoplasm benign, malignant
Cardiovascular system
Haematological
Infiltrates e.g. Amyloid, sarcoid
Autoimmune
Drugs / chemicals
Unknown idiopathic