diseases of the heart valves, pericardium and congenital heart disease Flashcards
What is stenosis of valves?
Failure of valves to open completely -> prevent forward flow
What is insufficiency of valves?
Failure of valves to close completely -> allow reverse flow
Some causes of valve stenosis?
- post inflammatory scarring eg rheumatic heart disease
- calcification
- congenital
Some causes of valve insufficiency?
- post inflammatory scarring eg rheumatic heart disease
- developmental eg Marfan’s
- degenerative eg Myxomatous degeneration
- infectious eg. syphilis, IE
Rules of valvular heart disease
- stenosis and insufficiency can occur at the same time
- more than 1 valve can be affected
- usually left sided valve affected
- structurally abnormal valve is at a higher risk
What are the 4 important valvular heart disease?
- Aortic valve calcification
- Mitral valve prolapse
- Rheumatic heart disease
- Infective endocarditis
What is aortic valve calcification?
Aortic stenosis caused by calcification due to age associated degeneration
What is mitral valve prolapse?
Myxoid degeneration of valvular cusps -> becomes thickened and rubbery
Ballooning of valvular cusps into left atrium -> loss of collagen and elastic tissue
results in Mitral Regurgitation
What are some examples of structurally abnormal valves?
- congenital bicuspid aortic valve
- valves damaged by RHD
- prosthetic valves
What is Rheumatic Fever?
- abnormal immune response to group A streptococcal antigens that cross react with host proteins following pharyngitis
- diagnosed by Jones criteria
- can cause rheumatic heart disease
What is acute rheumatic heart disease?
inflammation affecting all 3 layers of the heart aka pancarditis (includes pericarditis & myocarditis)
What are some macroscopic findings seen in acute rheumatic heart disease?
Aschoff’s bodies with caterpillar cells
T lymphocytes
plasma cells
What is the gross finding seen in acute rheumatic heart disease?
Small vegetations (masses) called verrucae formed by antibody complexes
What is seen in chronic rheumatic heart disease?
Fish mouth stenosis
Which valve is commonly affected in chronic rheumatic heart disease?
Mitral valve
What are the common valves involved in IE?
Mitral Valve
Aortic Valve
-> vegetations form in IE
How to diagnose IE?
modified Duke criteria
What conditions predispose to IE?
Abnormal valve
Microorganism seeding into blood
- procedure
- contaminated needle
- breaks in epithelial barriers
What bacteria is involved in Acute IE?
Staphylococcus Aureus for IV drug abusers
Acute IE
virulent microorganisms attacking normal valves
Subacute IE
weaker microorganisms attacking abnormal valves
What bacteria is involved in Subacute IE?
Streptococcus viridians (normal floral cavity)
Staphylococcus epidermis (prosthetic valve endocarditis)
Local complications of IE
- valve rupture
- myocardial ring abscess
- suppurative pericarditis
Distant complications of IE
- septic emboli (vegetation can dislodge): organ infarction and abscess formation
- glomerulonephritis
Complications of valvular heart disease
heart:
- LVH
- MI
- HF
- Arrhythmia
- Predisposition to IE
lung:
- congestion
- pulmonary hypertension
What are the types of pericarditis?
- Serous
- Fibrinous
- Suppurative
- Haemorrhagic
- Caseous
Entire pericardium covered by fibrin has a…
bread and butter appearance
What are the causes of pericarditis?
Infection
Trauma
Autoimmune
Metabolic
Iatrogenic
Neoplastic
Types of chronically healed pericarditis
adhesive pericarditis [no effect on cardiac function]
adhesive mediastinopericarditis [affects cardiac function]
constrictive pericarditis [affects cardiac function]
Left to Right shunt = Acyanotic
What are some examples of left to right shunts?
- VSD
- ASD
- Patent Ductus Arterioles (blood travels from higher pressure aorta to lower pressure pulmonary trunk)
Describe the Eisenmenger Syndrome (shunt reversal).
1) Left to right shunt will increase the pressure and volume of low pressure pulmonary circulation
2) Pulmonary arterioles will undergo medial hypertrophy and vasoconstriction
3) Right ventricular hypertrophy
4) Pulmonary vascular resistance increases and approaches systemic levels
5) Right to left shunt is created - deoxygenated blood enters the systemic circulation
What are some examples of obstruction in congenital heart disease?
- pulmonary and aortic stenosis
- coarctation of aorta
In coarctation of aorta with PDA:
deoxygenated blood from PT will top up loss of blood volume due to coarctation
=> lower limb will be cyanotic
In coarctation of aorta withOUT PDA:
lower limb will have a drop in BP
Right to left shunt = Cyanotic
What are some examples of right to left shunts?
5 Terrible Ts:
- Tetralogy of Fallot
- Transposition of great arteries
- Truncus arteriosus
- Tricuspid atresia
- Total anomalous pulmonary venous return
What is happening during Tetralogy of Fallot?
- Pulmonary stenosis
- RVH
- VSD
- Overriding aorta (aorta shifts to the right such that both RV and LV open into the aorta)
=> cyanosis
What is happening during Transposition of great arteries?
Aorta and PT switch places such that:
RV opens up into Aorta
LV opens up into Pulmonary Trunk
=> deoxygenated blood enters the systemic circulation without passing through the lungs
=> cyanosis
Complications of untreated congenital heart disease
LVH/RVH
HF
Pulmonary hypertension
Shunt reversal
IE
Paradoxical emboli (emboli from right side of heart enters systemic circulation through septal defects)
What is a common cause of mitral valve stenosis
RHD
In nonbacterial thrombotic endocarditis, what is observed?
small, non-infective, platelet-rich vegetations on heart valves
Define congenital heart disease
abnormalities of the heart and/or great vessels that are present at birth
