cardiovascular pathology II Flashcards
what is the rough amount for BP to be hypertension?
140/90
what chronic renal disease s can cause secondary hypertension?
- diabetic nephropathy, obstructive nephropathy
- renal vessel disease: renal artery stenosis
- adult polycystic kidney disease
- vasculitis
what are other causes of seconday hypertensoin?
coarctation of the aorta
endocrine disease
drugs
pregnancy
how does hypertension affect atherosclerosis?
accelerates atherosclerosis
what is arteriosclerosis?
hardening of the artery
what are two types of arteriosclerosis?
Hyaline and hyperplastic
what is the change seen in hyaline arteriosclerosis?
collagen replaced smooth muscle cells in the media
deposition of plasma proteins
what accelerates hyaline arteriosclerosis?
hypertension
D.M
age
what is the effect of hyaline arteriosclerosis?
increased rigidity causing lower complience
why are people susceptible to hypotension if they have hyaline arteriosclerosis?
the hyaline arteriosclerosis leads to decreased complience.
the auto regulation curve shifts to the right meaning the BP needs to be higher before it’s corrected
what is the difference between arteriosclerosis and atherosclerosis?
arteriosclerosis has no lipid deposition and no chronic inflammation
what is hyperplastic arteriosclerosis?
The BP causes fibrinoid necrosis in the vessel wall. there is then proliferation of the intimal cells
how does hypertension affect the heart?
Coronary artery atherosclerosis
left ventricular hypertrophy
what retinal changes are caused by hypertension?
flame haemorrhages
hard exudates
cotton wool spots
papilloedema
what is malignant/accelerated hypertension?
Raised diastolic pressure and end organ damage
what is the characteristic histology responsible for malignant/ accelerated hypertension?
hyperplastic arteriosclerosis
what is aortic dissection?
A tear in the intima causes the formation of a false lumen.
what is the clinical presentation of an aortic dissection?
A tearing pain down the shoulder blades
hypertension
asymmetrical pulses
what are the major risk factors for aortic dissection?
hypertension
abnormal media
pregnancy
what is a type A aortic dissection?
involving the ascending aorta
what is a type B aortic dissection?
not involving the ascending aorta
what aortic dissection is more serious?
Type A so management is normally immediate surgical repair
what is stenosis?
Failure of a valve to close completely meaning there can be reverse flow
what is the most common valve disease?
Aortic stenosis
what are common causes of aortic stenosis?
- cusp calcification of a bicuspid valve
- age related calcification of a tricuspid valve
- post rheumatic fever valve disease
why can aortic stenosis lead to left ventricular hypertrophy?
more left ventricular pressure is needed to drive blood into the aorta –> LV compensation
what is the presentation for aortic stenosis?
angina
syncope on exertion
congestive cardiac failure
what murmur is associated with aortic stenosis?
Ejection systolic murmur
what are common causes of mitral regurgitation?
mitral annulus mitral valve prolapse infective endocarditis post rheumatic fever rupture of papillary muscles after MI
what are the normal causes of acute mitral regurgitation?
infective endocarditis
MI causing papillary muscle rupture
what are the consequences of acute mitral regurgitation?
No time to compensate so blood will flow back into the LA causing the pressure to rise. the pressure is transmitted towards the pulmonary circulation causing pulmonary oedema
what are causes of chronic mitral regurgitation?
dilatation of a mitral valve ring
mitral valve prolapse
post rheumatic fever
papillary muscle ischaemia
what is the most common cause of mitral valve regurgitation?
Mitral valve prolapse
what happens in mitral valve prolapse?
the normal dense collagen/elastin matric of the valve is replaces with loos myxomatous connective tissue
what bacteria can cause infective endocarditis?
Streptococci, S.viridans
S.aureus in IV drug users
In infective endocarditis a vegetation forms on the valve, what is a vegetations?
A thrombus containing microorganisms
what are the complications of infective endocarditis?
disturbance of valve function
embolism which can present as stroke
formation of antigen=antibod immune complexes
what are the investigations for infective endocarditis?
Blood cultures: 3 sets from different sites taken an hour apart before antibiotics
- transoesophageal echocardiography
what is dukes major criteria for diagnosing infective endocarditis?
Major criteria:
- positive blood cultures with typical microrganisms in 2 seperate cultures. persistant positive blood cultures taken over 12 hours apart
three or more cultures taken over more than 1 hour apart
evidence of endocardial involvement on echocardiography such as new valve regurg, abscess or vegetations
what is dukes minor criteria for diagnosing infective endocarditis?
- predisposing valve or cardiac abnormality
- temperature above 38
- vasculitic phenomena
- embolic phenomena
- positive blood cultures but not meeting major critera
what is needed to diagnose infective endocarditis?
two major criteria
one major and 3 minor
5 minor
what is heart failure?
when the pumping action of the heart doesn’t meet the needs of the body
what is systolic failure?
failure of the pumping action when the ventricle is in systole. the ventricle is normally dilated and fails to contract normally so the ejection fraction is reduced
what is diastolic failure?
failure of the ventricle to fill due to increased stiffness of the wall.
what is BNP?
A Hormone secreted by ventricular myocytes in response to volume or pressure overload of the LV.
