Download Cardiovascular - WordPress.com

Pneumonic for secondary hypertension
RENAL
Renal
-
A.G.N
C.R.F
Renal artery stenosis
Renal vasculator
Polycystic renal disease
Renin secreting tumours
Endocrine
- Adrenocortical
- Cushings
- C.A.H.
- Dr aldosteronis
- Thyroid
- overactive
- underactive
- Pituitary
- A.C.T.H
- G.H.
- S.I.A.D.H.
- Pheochromacytoma
- Pregnancy
- Drugs
- MAOIs
- Tyramine (foods)
- Sympathominitors
- O.C.P.
- Glucocorticoids
- Licorice
Neurogenic
- Increased I.C.P.
- Stress / pain
Arterial
-
Coarctation
Ar?????? / polyarteritis
Loading
- Increased CO
- Increased blood volume
Section 1
Cardiovascular
1) The probability of a 55 year old smoker with hypertension and hypercholesterolaemia
developing coronary heart disease in the next 8 years is:
a)
b)
c)
d)
e)
5%
10%
25%
50%
75%
2) Chronic ischaemic heart disease is characterised by all of the following EXCEPT:
a)
b)
c)
d)
e)
diffuse subendocardial fibrosis
diffuse myocardial atrophy
severe stenosing coronary atherosclerosis
diffuse, small myocardial scars
evolution to congestive heart failure
3) Which one of the following conditions is associated with coronary atherosclerosis?
a)
b)
c)
d)
e)
stable angina only
unstable angina only
Prinzmetal’s angina only
stable and unstable angina
all of the above
4) Which one of the following conditions is MOST commonly accompanied by ST
segment elevation on the ECG?
a)
b)
c)
d)
e)
stable angina only
unstable angina only
Prinzmetal’s angina only
stable and unstable angina
all of the above
5) Which one of the following conditions is MOST commonly accompanied by ST
segment depression?
a)
b)
c)
d)
e)
stable angina only
unstable angina only
Prinzmetal’s angina only
stable and unstable angina
all of the above
6) With regard to abdominal aortic aneurysms, which is INCORRECT?
a)
b)
c)
d)
e)
they have a familial tendency not solely accounted for by atherosclerosis
they are most frequent between the renal arteries and iliac bifurcation
they have a risk of rupture of 5-10% per year if >5cm diameter
they are rare before the age of 50 years
they are more common in females
7) With regard to aortic dissection, which is INCORRECT?
a) it tends to occur in 40-60 year old men
b) approximately 90% of non-traumatic cases occur in patients with antecedent
hypertension
c) it is usually associated with marked dilatation of the aorta
d) it is unusual in the presence of substantial atherosclerosis
e) it is usually caused by an intimal tear within 10cm of the aortic valve
8) Which one of the following conditions frequently causes reversible injury to
myocardial cells?
a)
b)
c)
d)
e)
stable angina only
unstable angina only
Prinzmetal’s angina only
stable and unstable angina
all of the above
9) Using the following key, the likelihood of complications of an acute myocardial
infarction, from MOST to LEAST common is:
Q
R
S
T
U
a)
b)
c)
d)
e)
-
left ventricular failure
rupture of free wall/papillary muscle
thromboembolism
cardiogenic shock
arrhythmias
R,S,T,Q,U,
T,Q,U,S,R,
U,Q,S,T,R,
Q,U,T,S,R,
U,Q,S,R,T,
10) The pathology of unstable angina primarily involves:
a)
b)
c)
d)
e)
increased blood viscosity
altered dynamics of myocardial blood flow
severe fixed atherosclerotic stenosis
mural thrombosis of an epicardial artery
mechanisms separate to the pathology of myocardial infarction
11) Which one of the following conditions is associated with a very high risk of
myocardial infarction?
a)
b)
c)
d)
e)
stable angina only
unstable angina only
Prinzmetal’s angina only
stable and unstable angina
all of the above
12) Regarding cardiogenic shock:
a)
b)
c)
d)
e)
this is partly due to the systolic stretch phenomenon
depletion of ATP plays a significant role
the mortality associated with this condition is approximately 85%
it is usually indicative of a large infarct
all of the above are true
13) The histological appearance of contraction bands in association with acute
myocardial infarction indicate:
a)
b)
c)
d)
e)
previous old myocardial infarctions
early aneurismal formation
compensatory responses to decreased myocardial contractility
a right ventricular infarct
recent reperfusion therapy
14) After occlusion of a coronary artery:
a) the ischaemia is most pronounced in the epicardial region
b) loss of contractility only occurs when ultra structural changes in the myocyte are
present
c) reperfusion of the ischaemic area can result in new cellular damage due to the
generation of oxygen free radicals
d) Q waves on the ECG are diagnostic of transmural infarction
e) none of the above are true
15) In the typical right dominant heart, occlusion of the right coronary artery:
a)
b)
c)
d)
e)
will produce a lesion in the anterior 2/3 of the interventricular septum
is less common than occlusion of the left circumflex artery
will not affect the interventricular septum
will produce a lesion in the anterior wall of the left ventricular
none of the above are true
16) Which of the following is the LEAST common cause of aneurysm formation?
a)
b)
c)
d)
e)
cervical rib
ankylosing spondylitis
atheroma
coronary angioplasty
syphilis
17) The MOST common site of cerebral aneurysm is:
a)
b)
c)
d)
e)
middle meningeal artery
middle cerebral artery
anterior cerebral artery
anterior meningeal artery
posterior cerebral artery
18) Which of the following statements about aneurysm is INCORRECT?
a)
b)
c)
d)
e)
they rupture at the apex rather than at the sides
traumatic aneurysms most commonly involve lower limb arteries
they more commonly leak when the diameter is greater than 5cm
atheromatous aneurysms most commonly involve the aorta
they may be infective in origin
19) Which of the following vessels is LEAST susceptible to aneurismal dilation?
a)
b)
c)
d)
e)
innominate artery
subclavian artery
ascending thoracic aorta
brachial artery
carotid artery
20) Pathologic features or aortic dissection include all of the following EXCEPT:
a)
b)
c)
d)
e)
elastic fragmentation
inflammatory cell infiltrate
cystic medial necrosis
focal medial fibrosis
intimal tear
21) Which of the following patterns of arterial blood supply is INCORRECT?
a)
b)
c)
d)
e)
the brain has a parallel arterial system
the kidney has end-arteries
the liver has a double blood supply
the forearm has a parallel arterial system
the jejunum has end-arteries
22) Which of the following is NOT commonly associated with berry aneurysms?
a)
b)
c)
d)
e)
pre-existing cerebral arteriovenous malformation
rupture when diameter exceeds 10mm
smooth muscle discontinuity in media
polycystic ovary disease
absence at birth
23) Which of the following vessels is LEAST susceptible to atheromatous plaque
formation?
a)
b)
c)
d)
e)
superior mesenteric artery
popliteal artery
Circle of Willis
descending thoracic aorta
internal carotid artery
24) Causes of cardiogenic shock include all of the following EXCEPT:
a)
b)
c)
d)
e)
myocardial damage
tamponade
excessive blood loss
arrhythmias
outflow obstruction
25) “Caisson” disease refers to:
a)
b)
c)
d)
e)
systemic emboli
pulmonary emboli
amniotic fluid emboli
air emboli
fat emboli
26) In acute myocardial infarction, which change will occur in the time frame indicated:
a)
b)
c)
d)
e)
ATP reduced to 50% of normal
microvascular injury
onset of irreversible cell injury
ATP reduced to 10% of normal
loss of contractility
- 25 minutes
- after 3-4 hours
- 10 minutes
- 60 minutes
- 1-2 minutes
27) Acute myocardial infarction:
a)
b)
c)
d)
e)
is isolated to the right ventricle in < 5% of cases
involves the atria in 1-2% of cases
is due to left anterior descending artery critical blockage in 70% of cases
is due to right main artery critical blockage in 10% of cases
is due to critical blockage of left circumflex artery in 35% of cases
28) 1-2 hours following acute myocardial infarction, the change occurring in myocardium
is:
a)
b)
c)
d)
e)
ultra structural cellular features of irreversible damage
the appearance of “wavy” fibres
staining defects in preparations with tetrazolium dye
the appearance of classical features of coagulative necrosis
none of the above
29) The MOST frequent complication of acute myocardial infarction is:
a)
b)
c)
d)
e)
cardiogenic shock
thromboembolism
congestive cardiac failure
arrhythmia
deep venous thrombosis
30) Of the following complications of acute myocardial infarction, the MOST frequently
occurring is:
a)
b)
c)
d)
e)
ventricular rupture
sudden death
pulmonary oedema
cardiogenic shock
thromboembolism
31) Subendocardial myocardial infarction:
a)
b)
c)
d)
e)
is reliably predicted by the absence of Q waves on the ECG
is usually associated with diffuse coronary atherosclerosis
is associated with plaque rupture without thrombosis
is associated with vessel thrombosis, but not plaque rupture
is usually associated with plaque rupture and overlying thrombosis
32) Sudden cardiac death:
a)
b)
c)
d)
e)
is most frequently due to ventricular wall rupture
is most frequently due to aortic stenosis
is often the first clinical manifestation of ischaemic heart disease
is rarely associated with single vessel critical coronary artery stenosis
is associated with acute myocardial infarction in 90% of cases
33) Which is the MOST frequent cardiac valve abnormality?
a)
b)
c)
d)
e)
mitral stenosis
mitral incompetence
aortic incompetence
aortic stenosis
pulmonary incompetence
34) A patient presents unwell, four weeks after having a streptococcal pharyngitis.
Which of the following would confirm a diagnosis of rheumatic fever?
a)
b)
c)
d)
e)
fevers and pan systolic apical murmur
fevers and a raised ASO titre
migratory polyarthritis and subcutaneous nodules
fever and raised ESR
a raised ASO titre, pan systolic murmur and migratory polyarthritis
35) Abdominal aortic aneurysms:
a)
b)
c)
d)
e)
usually involve the renal arteries
usually involve the iliac arteries
are more common in post menopausal women than men of the same age group
are familial
if 4-5 cm in diameter, have an annual risk of rupture of approximately 10-15%
36) A 65 year old man presents with left-sided chest pain and ECG features consistent
with pericarditis. Which is the MOST likely cause of this condition?
a)
b)
c)
d)
e)
systemic lupus erythematosis
renal failure
trauma
post myocardial infarction
bacterial infection
37) The MOST common cause of pericarditis is:
a)
b)
c)
d)
e)
SLE
drug hypersensitivity
trauma
post myocardial infarction
bacteria
38) The MOST common pathogens of infective endocarditis are:
a)
b)
c)
d)
e)
staphylococcal
enterobacteriaceae
streptococcal
chlamydial
fungal
39) All of the following are features of rheumatic fever EXCEPT:
a)
b)
c)
d)
e)
carditis
subcutaneous nodules
erythema nodosum
elevated antistreptolysin
Aschoff bodies in the heart
40) Abdominal aortic aneurysms:
a)
b)
c)
d)
e)
do not develop before the age of 50
are not familial
are most common in women
with a diameter ≤ 4cm have a risk of rupture of 2% per year
with a diameter ≥ 5cm have a risk of rupture of 30% per year
41) In ischaemic heart disease:
a) acute myocardial infarction has a circadian peak in the mid to late afternoon
b) 30% of myocardial infarcts are “silent”
c) an eccentric atherosclerotic plaque is more likely to rupture than a circumferential
one
d) atherosclerotic plaque rupture with overlying thrombosis will progress to infarction
if left untreated
e) an atherosclerotic plaque causing 60% stenosis will be unlikely to cause
infarction if it ruptures and becomes complicated
42) The vessel most intensely involved by atherosclerotic plaques is:
a)
b)
c)
d)
e)
abdominal aorta
coronary artery
internal carotid artery
popliteal artery
middle cerebral artery
43) Which of the following is the LEAST significant risk factor for atherosclerosis?
a)
b)
c)
d)
e)
obesity
hypercholesterolaemia
hypertension
diabetes
cigarette smoking
44) A major risk factor that predisposes towards atherosclerosis is:
a)
b)
c)
d)
e)
male gender
diabetes
obesity
family history of premature atherosclerosis
physical inactivity
45) Atheroma predominantly effects:
a)
b)
c)
d)
e)
the intima
the media
the adventitia
the media and adventitia
the whole arterial wall
46) The foam cells in atherosclerotic lesions are:
a)
b)
c)
d)
intimal cells full of lipid
monocytes full of lipid
smooth muscle cells that have migrated from the media to the intima
platelets that are adherent to the plaque
47) Which is NOT a feature of atheromatous plaques?
a)
b)
c)
d)
e)
it mainly involves the muscular and elastic arteries
lesions tend to be covered with a fibrous cap of smooth muscle cells
the edges (“shoulder”) contain macrophages and T-cells
the core is a necrotic mass of cholesterol and other lipids with foam cells
it mainly occurs within the tunica media
48) After the abdominal aorta, in general, which site is the most heavily effected by
atheroma?
a)
b)
c)
d)
e)
descending thoracic aorta
coronary arteries
popliteal artery
internal carotid artery
vessels of the Circle of Willis
49) The hyperlipidaemic contribution to the pathogenesis of atheroma is thought to occur
via:
a)
b)
c)
d)
e)
atheroma macrophages uptaking lipid via LDL receptors
hyperviscosity secondary to hyperlipidaemia
oxidation of lipids within the atheroma
the thrombogenic nature of lipids
apolipoprotein B-48
50) Regarding haemorrhagic infarction of the brain, which of the following is NOT true?
a) it usually results from an embolic event
b) it usually contains multiple petechial haemorrhages which may be confluent
c) the distinction between this and non haemorrhagic infarcts is clinically
insignificant
d) the haemorrhages are presumed to be secondary to reperfusion injury
e) the size of it will depend in part upon the collateral blood supply to that area
51) The most common site of origin of emboli causing cerebrovascular disease is:
a)
b)
c)
d)
e)
common carotid artery
internal carotid artery
the heart
either end of basilar artery
intra-cranial vessels
Section 1
Cardiovascular – Answers
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
C
A
E
C
D
E
C
E
C
D
B
E
E
C
E
E
C
A
D
B
E
D
A
C
D
E
A
B
D
C
B
C
D
C
D
D
D
C
C
D
C
42
43
44
45
46
47
48
49
50
51
A
A
B
A
B
E
B
C
C
C
Section 2
1) Which is NOT a compensatory change in congestive heart failure?
a)
b)
c)
d)
e)
myofibre hypertrophy
myofibre stretch
bradycardia
blood volume expansion
ventricular dilatation
2) Which is NOT a cause of pure right sided heart failure?
a)
b)
c)
d)
e)
tricuspid valvular disease
pulmonary embolus
COAD
hypertension
myocarditis
3) Which is a major (Jones) criteria for rheumatic fever?
a)
b)
c)
d)
e)
erythema nodosum
fever
past history of rheumatic fever
raised ESR
polyarthritis
4) Which endothelial product is prothrombotic?
a)
b)
c)
d)
e)
prostacyclin
thrombomodulin
plasminogen activator
heparin-like molecules
tissue-factor
5) Blockage of the left circumflex artery will cause infarction in:
a)
b)
c)
d)
e)
anterior left ventricle
posterior septum
lateral left ventricle
apex
right ventricle
6) Morphological changes in an acute myocardial infarction include:
a)
b)
c)
d)
e)
coagulative necrosis within 1 hour
ATP 10% of normal within 10 minutes
yellow soft demarcated area within 3-10 days
new blood vessel formation at 3 days
loss of contractility within 5 minutes
7) What organism most commonly causes SBE?
a)
b)
c)
d)
e)
staphylococcus aureus
staphylococcus epidermidis
group A streptococcus
α haemolytic streptococcus
haemophilus
8) Regarding aortic dissection:
a)
b)
c)
d)
e)
there is a blood-filled channel along the laminar planes of the intima
hypertension is present in 75% of cases
is mostly in 40-60 year old women
there is marked dilatation of the aorta
is unusual in severe atherosclerosis
9) Which is a major risk factor for atherosclerosis?
a)
b)
c)
d)
e)
obesity
physical inactivity
stress (type A personality)
hypertension
homocysteine
10) Which vessel is least likely to develop atherosclerosis?
a)
b)
c)
d)
e)
mesenteric artery
Circle of Willis
descending thoracic aorta
internal carotid artery
popliteal artery
11) Bicuspid aortic valve – which is FALSE?
a)
b)
c)
d)
e)
incidence is 1-2%
no increased predisposition to aortic stenosis
increased association of coarctation and dissection
increased risk of infective endocarditis
increased risk of valve incompetence
12) Major Jones criteria for rheumatic fever include:
a)
b)
c)
d)
e)
fever
previous rheumatic fever
ESR > 20
prolonged PR interval on ECG
polyarthritis
13) Hypertension is a risk factor for all EXCEPT:
a)
b)
c)
d)
e)
renal failure
heart failure
ischaemic heart disease
aortic stenosis
cerebrovascular accident
14) Aortic dissection:
a)
b)
c)
d)
e)
most common in 40-60 year old females
are most frequently associated with aneurysms
extend along the intimal plane of the aorta
usually occur 2cm from the aortic valve
type A involves the great vessels of aortic arch
15) An anticoagulant produced by endothelium is:
a)
b)
c)
d)
e)
thrombomodulin
factor III (vWF)
plasminogen activator inhibitor
endothelin
interleukin-6
16) Endothelial cells:
a)
b)
c)
d)
e)
have many pinocytic vesicles
form junctional complexes
contain Weibel-Palade bodies
elaborate von Willebrand factor
have all of the above characteristics
17) The cardothelium does not:
a)
b)
c)
d)
e)
serve as a semi-permeable membrane
migrate to the media in response to injury
regulate thrombosis, thrombolysis and platelet adherence
regulate leukocyte interactions with vessel wall
metabolise hormones
18) The endothelium does not:
a)
b)
c)
d)
e)
have many synthetic properties
have many metabolic properties
maintain the non-thrombogenic blood tissue interface
constrict to reduce flow in response to drugs or hormones
modify lipoproteins in the arterial wall
19) Endothelial cells are not activated by:
a)
b)
c)
d)
e)
cytokines
high PCO2
bacterial products
hypoxia
haemodynamic forces
20) Endothelial cells do not elaborate:
a)
b)
c)
d)
e)
prostacyclin and NO/EDRF
plasmin
heparin-like molecules
endothelin and ACE
extracellular matrix
21) Which of the following forms of vasculitis does not involve glomeruli?
a)
b)
c)
d)
e)
Henoch Schoenlein purpura
Wegeners granulomatosus
polyarthritis nodosa
Goodpastures
SLE
22) Which of the following vasculilides is associated with a raised pANCA?
a)
b)
c)
d)
e)
rocky mountain spotted fever
drug induced
rheumatoid
cryoglobulinaemia
Churg Strauss
23) In which of the following groups of vasculitis is the pathogenesis well defined?
a)
b)
c)
d)
e)
Takayasu pulseless disease
microscopic polyangiitis
polyarthritis nodosa
giant cell arteritis
Buergers disease (thrombophlebitis obliterans)
24) In valvular disease:
a) in nonbacterial thrombotic endocarditis, small sterile vegetations are present on
either or both sides of the valve leaflets
b) group A β–haemolytic streptococci is the most common causative agent of
infective endocarditis
c) 12% of the population have congenitally bicuspid aortic valves
d) mitral regurgitation is the most frequent of all valvular abnormalities
e) ankylosing spondylitis is a cause of aortic regurgitation
25) In myocardial disease:
a) in hypertrophic cardiomyopathy, the free wall of the left ventricle is
disproportionately thickest
b) dilated cardiomyopathy has a familial occurrence in 20-30% of cases
c) EBV is a common cause of viral myocarditis
d) giant cell myocarditis has a relatively good prognosis
e) in haemochromatosis, iron deposition is preferentially in the conduction system
26) In myocardial infarction:
a) white people are twice as likely to suffer a myocardial infarction compared with
black people
b) irreversible cell injury occurs after one hour of ischaemia
c) the right coronary artery supplies the ventricular septum
d) coagulative necrosis begins within 24 hours of a myocardial infarction
e) myocardial infarctions are silent in 5% of cases
27) Regarding atherosclerosis:
a)
b)
c)
d)
e)
fatty streaks cause disturbance in blood flow
fatty streaks appear in aortas of all children older than one year
atheromatous plaques are composed of a luminal surface of foam cells
coronary artery lesions are often mainly fatty atheromas
the lipid in a plaque is primarily triglyceride
28) After the abdominal aorta, the next most affected vessel with atherosclerosis is:
a)
b)
c)
d)
e)
Circle of Willis
thoracic aorta
axillary artery
popliteal artery
internal carotid artery
29) Major modifiable risk factors for atherosclerosis include:
a)
b)
c)
d)
e)
age
type A personality
increased plasmo homocysteine
diabetes mellitus
physical inactivity
30) Regarding cellular depletion of ATP in myocardial infarction:
a)
b)
c)
d)
e)
10% at 10 minutes
50% at 20 minutes
there is no ATP in myocytes
10% at 40 minutes
50% leading to irreversible injury
Section 2
Answers
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
C
D
E
E
C
C
D
E
D
A
B
E
C
E
A
E
B
D
B
B
no answer
no answer
no answer
no answer
no answer
no answer
no answer
no answer
no answer
no answer
Section 3
1) Which of the following is not a primary cause of diastolic dysfunction?
a)
b)
c)
d)
e)
massive left ventricular hypertrophy
myocardial fibrosis
aortic regurgitation
deposition of amyloid
constrictive pericarditis
2) At autopsy, the heart of patients having CHF is characterised by all of the following
EXCEPT:
a)
b)
c)
d)
e)
increased weight
increased capillary density
progressive wall thinning
chamber dilatation
microscopic changes of hypertrophy
3) Left-sided heart failure is most often caused by the following, EXCEPT:
a)
b)
c)
d)
e)
ischaemic heart disease
hypertension
aortic and mitral valvular disease
myocardial diseases
pulmonary diseases
4) The most common cause of IHD syndrome is:
a)
b)
c)
d)
e)
stenosing coronary atherosclerosis
intraluminal thrombosis
rupture or fissure of an atherosclerotic plaque
platelet aggregation
coronary vasospasm
5) Compensatory vasodilation is not sufficient to meet increased myocardial demand,
beyond an obstruction of a major coronary artery by:
a)
b)
c)
d)
e)
45%
55%
65%
75%
85%
6) Which of the following is not thought to be associated with acute rupture of an
atherosclerotic plaque?
a)
b)
c)
d)
e)
vasospasm
tachycardia
circadian periodicity
intraplaque haemorrhage
raised intrathoracic pressure
7) Which of the following is associated with ST segment elevation on the ECG?
a)
b)
c)
d)
e)
stable angina
Prinzmetal’s angina
Unstable angina
All of the above
None of the above
8) Which of the following is incorrect regarding Q wave infarcts?
a)
b)
c)
d)
acute mortality in non-Q wave infarcts is half that in patients with Q wave infarcts
non-Q wave infarcts have a low early mortality rate
non-Q wave infarcts have a high late mortality rate
the presence or absence of Q waves reliably predicts the distinction between
subendocardial and transmural infarcts
e) none of the above
9) What proportion of myocardial infarcts occur in people under the age of 65:
a)
b)
c)
d)
e)
65%
55%
45%
35%
25%
10) In the typical right dominant heart, occlusion of the LAD coronary artery will produce
an infarct in the:
a)
b)
c)
d)
e)
anterior two thirds of the interventricular septum
lateral wall of the left ventricle
posterior one third of the interventricular septum
inferior wall of the left ventricle
posterior wall of the left ventricle
11) Which is the least common complication of acute myocardial infarction?
a)
b)
c)
d)
e)
cardiac arrhythmia
left ventricular failure
cardiogenic shock
rupture of free wall, septum or papillary muscle
thromboembolism
Section 3
Answers
1
2
3
4
5
6
7
8
9
10
11
no answer
…..
….
….
….
….
….
….
….
….
…..
Ischaemic Heart Disease
Definition:
Group of four syndromes which result in myocardial ischaemia.
Imbalance between perfusion of myocardium and its demand for oxygenated
blood.
Results in deficiency of oxygen and nutrient substances and reduced clearance
of metabolites.
Four Syndromes:
1 Myocardial infarction
2 Angina pectoris – three types: Stable
Prinzmetal
Unstable
3 Chronic ischaemic heart disease with heart failure
4 Sudden cardiac death (fatal arrhythmia)
Risk
Unmodifiable:
Major:
Minor:
gender, family history, age, genetic predisposition,
smoking, diabetes mellitus, HT, hypercholesterolaemia
exercise, obesity, ETOH, increased CHO diet, increased
homocysteine, stress (type A personality), post menopause,
lipoprotein
Pathogenesis:
1 Atherosclerosis → know definition atherosclerosis
Disease of intima of muscular and elastic arteries characterised by
atheromatosis plaques in intima which project into lumen of vessel
 Atherosclerosis can cause fixed coronary obstructions.
 >90% people with IDH have coronary atherosclerosis which decreases the
radius and compromises the flow.
 Most have ≥ 1 lesion which decreases cross sectional area of vessel lumen by
≥ 75%.
 Lesions usually in first few centimetres of artery
2
3
4
Role of acute changes in atherosclerotic plaque
Role of coronary thrombosis
Role of vasoconstriction
* 2, 3 and 4 cause sudden change in coronary vessel potency and blood flow to
myocardium
Acute changes in plaque
 Haemorrhage into plaque (sudden increased volume)
 Rupture / fissuring of plaque
 Erosion / ulceration overlying endothelium
+ thrombosis
Thrombosis
pH adhesion, activation, aggregation (exposed plaque contents and endothelial BM)
+ mediators of coagulation leads to fibrin clot
consequences of thrombosis (decreased lumen/occlude lumen)
 Occlusive leads to transmural AMI
 Non-occlusive leads to unstable angina, subendocardial AMI, sudden cardiac death
 Embolise downstream
 + smooth muscle contraction
 + TxA2 and pH constituents which further + thrombosis
 nb lipoprotein a (on LDL) can – fibronolysis
Vasoconstriction
SM + by:
Circulating adrenergic agonists
Locally released pH contents
Inflammation mediators
Decreased secretion NO by damaged endothelium
Consequences of vasoconstriction
 Decreased vessel lumen
 Altered forces in vessel – increased risk plaque rupture
Myocardium is O2 dependent tissue
Coronary perfusion / O2 delivery
(???? Are the “+” an abbreviation of increased????
“-“ perhaps negate or similar)
Ischaemic Heart Disease
Myocardial ischaemia = imbalance between supply (perfusion) and demand (for O2)
→ insufficiency of O2
→ reduced availability of nutrients
→ inadequate removal of waste products
Mostly (>90%) due to decreased coronary blood flow secondary to atherosclerosis
Pathogenesis
1
2
3
4
Fixed coronary obstruction
Acute plaque change
Coronary thrombosis
Vasoconstriction
Normal coronary a.
fixed obstruction
(typical angina)
plaque disruption
severe fixed obstruction
(chronic IHD)
variable obstruction
(USAP, subendo. MI)
occlusive thrombus
(transmural MI)
sudden death
Angina
Characterised by paroxysmal and recurrent attacks of precordial chest pain
1 stable angina
2 Prinzmetal variant angina
3 Unstable angina
Myocardial Infarction
Death of heart muscle
Leading cause of death in industrialised countries
Types
1 transmural – full thickness, single a. territory
2 subendocardial – inner 1/3 to ½ , extends beyond a. territory
Risk Factors
As for atherosclerosis:
1 major, non-modifiable (age, male, genetic)
2 major, modifiable (lipids, HT, cigs, DM)
3 other (obesity, inactivity, stress, homocysteine, etc)
Pathogenesis
1 atherosclerotic plaque change
2 platelet adhesion, aggregation, activation
3 other mediators + (2) → extrinsic coagulation
4 occlusive thrombus
→ cell death throughout anatomic region supplied by a.
outcome depends on severity and duration of occlusion
Location
1 LAD (40-50%) → ant. LV, ant. Septum, apex
2 RCA (30-40%) → inf-post. LV and RV, post. septum
3 LCX (15-20%) → lat. LV
Morphology
Cellular:
Seconds
< 2 min
10 min
40 min
> 1 hour
Time
0-4 hours
4 hours – 3 days
1-7 days
3-10 days
7-14 days
2-8 weeks
: onset of ATP depletion
: loss of contractility
: ATP 50% of normal
: ATP 10% of normal (irreversible cell injury)
: microvascular injury
Light microscopy
subcellular change (EM)
coagulative necrosis, haemorrhage, oedema
neutrophils
macrophages → phagocytosis, granulation
granulation tissue, new blood vessels
increased collagen, decreased cells
Gross features
dark mottling
yellow-tan & soft
red-grey borders
grey-white scar
Reperfusion
Before 20 minutes → may prevent all necrosis
After 20 minutes → can salvage some cells
Critically damaged myocytes die quicker (contraction band necrosis, ?↑Ca2+)
Small amount of new cellular damage (?O2 free radicals)
“stunned myocardium” = prolonged (3d) post ischaemic ventricular dysfunction
“hibernating myocardium” = chronically depressed function
Complications
Around 75% of MI patients suffer complications
Depend on MI size, site and transmural extent
1
2
3
4
5
6
7
8
9
10
contractile dysfunction → LVF, cardiogenic shock
arrhythmias (s. brady, PVCs, VT/VF, asystole, heart block (inf MI))
myocardial rupture
pericarditis
RV infarction
infarct extension/expansion
mural thrombus → embolism
ventricular aneurysm
papillary muscle dysfunction → MR
progressive late CCF
Chronic IHD
Progressive heart failure as a result of ischaemic myocardial damage
Sudden Cardiac Death
Unexpected death from cardiac causes
Causes: IHD
Other – congenital, valvular disease, cardiomyopathy, conduction, abnormalities
Ultimate cause nearly always VF or asystole