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Pneumonic for secondary hypertension
R E N A L 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) 5%b) 10%c) 25%d) 50%e) 75%
2) Chronic ischaemic heart disease is characterised by all of the following EXCEPT:
a) diffuse subendocardial fibrosisb) diffuse myocardial atrophyc) severe stenosing coronary atherosclerosisd) diffuse, small myocardial scarse) evolution to congestive heart failure
3) Which one of the following conditions is associated with coronary atherosclerosis?
a) stable angina onlyb) unstable angina onlyc) Prinzmetal’s angina onlyd) stable and unstable anginae) all of the above
4) Which one of the following conditions is MOST commonly accompanied by ST segment elevation on the ECG?
a) stable angina onlyb) unstable angina onlyc) Prinzmetal’s angina onlyd) stable and unstable anginae) all of the above
5) Which one of the following conditions is MOST commonly accompanied by ST segment depression?
a) stable angina onlyb) unstable angina onlyc) Prinzmetal’s angina onlyd) stable and unstable anginae) all of the above
6) With regard to abdominal aortic aneurysms, which is INCORRECT?
a) they have a familial tendency not solely accounted for by atherosclerosisb) they are most frequent between the renal arteries and iliac bifurcationc) they have a risk of rupture of 5-10% per year if >5cm diameterd) they are rare before the age of 50 yearse) 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 menb) approximately 90% of non-traumatic cases occur in patients with antecedent
hypertensionc) it is usually associated with marked dilatation of the aortad) it is unusual in the presence of substantial atherosclerosise) 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) stable angina onlyb) unstable angina onlyc) Prinzmetal’s angina onlyd) stable and unstable anginae) 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 - left ventricular failureR - rupture of free wall/papillary muscleS - thromboembolismT - cardiogenic shockU - arrhythmias
a) R,S,T,Q,U,b) T,Q,U,S,R,c) U,Q,S,T,R,d) Q,U,T,S,R,e) U,Q,S,R,T,
10) The pathology of unstable angina primarily involves:
a) increased blood viscosityb) altered dynamics of myocardial blood flowc) severe fixed atherosclerotic stenosisd) mural thrombosis of an epicardial arterye) 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) stable angina onlyb) unstable angina onlyc) Prinzmetal’s angina onlyd) stable and unstable anginae) all of the above
12) Regarding cardiogenic shock:
a) this is partly due to the systolic stretch phenomenonb) depletion of ATP plays a significant rolec) the mortality associated with this condition is approximately 85%d) it is usually indicative of a large infarcte) all of the above are true
13) The histological appearance of contraction bands in association with acute myocardial infarction indicate:
a) previous old myocardial infarctionsb) early aneurismal formationc) compensatory responses to decreased myocardial contractilityd) a right ventricular infarcte) recent reperfusion therapy
14) After occlusion of a coronary artery:
a) the ischaemia is most pronounced in the epicardial regionb) loss of contractility only occurs when ultra structural changes in the myocyte are
presentc) reperfusion of the ischaemic area can result in new cellular damage due to the
generation of oxygen free radicalsd) Q waves on the ECG are diagnostic of transmural infarctione) none of the above are true
15) In the typical right dominant heart, occlusion of the right coronary artery:
a) will produce a lesion in the anterior 2/3 of the interventricular septumb) is less common than occlusion of the left circumflex arteryc) will not affect the interventricular septumd) will produce a lesion in the anterior wall of the left ventricular e) none of the above are true
16) Which of the following is the LEAST common cause of aneurysm formation?
a) cervical ribb) ankylosing spondylitisc) atheromad) coronary angioplastye) syphilis
17) The MOST common site of cerebral aneurysm is:
a) middle meningeal arteryb) middle cerebral arteryc) anterior cerebral arteryd) anterior meningeal arterye) posterior cerebral artery
18) Which of the following statements about aneurysm is INCORRECT?
a) they rupture at the apex rather than at the sidesb) traumatic aneurysms most commonly involve lower limb arteriesc) they more commonly leak when the diameter is greater than 5cmd) atheromatous aneurysms most commonly involve the aortae) they may be infective in origin
19) Which of the following vessels is LEAST susceptible to aneurismal dilation?
a) innominate arteryb) subclavian arteryc) ascending thoracic aortad) brachial arterye) carotid artery
20) Pathologic features or aortic dissection include all of the following EXCEPT:
a) elastic fragmentationb) inflammatory cell infiltratec) cystic medial necrosisd) focal medial fibrosise) intimal tear
21) Which of the following patterns of arterial blood supply is INCORRECT?
a) the brain has a parallel arterial systemb) the kidney has end-arteriesc) the liver has a double blood supplyd) the forearm has a parallel arterial systeme) the jejunum has end-arteries
22) Which of the following is NOT commonly associated with berry aneurysms?
a) pre-existing cerebral arteriovenous malformationb) rupture when diameter exceeds 10mmc) smooth muscle discontinuity in mediad) polycystic ovary diseasee) absence at birth
23) Which of the following vessels is LEAST susceptible to atheromatous plaque formation?
a) superior mesenteric arteryb) popliteal arteryc) Circle of Willisd) descending thoracic aortae) internal carotid artery
24) Causes of cardiogenic shock include all of the following EXCEPT:
a) myocardial damageb) tamponadec) excessive blood lossd) arrhythmiase) outflow obstruction
25) “Caisson” disease refers to:
a) systemic embolib) pulmonary embolic) amniotic fluid embolid) air embolie) fat emboli
26) In acute myocardial infarction, which change will occur in the time frame indicated:
a) ATP reduced to 50% of normal - 25 minutesb) microvascular injury - after 3-4 hoursc) onset of irreversible cell injury - 10 minutesd) ATP reduced to 10% of normal - 60 minutese) loss of contractility - 1-2 minutes
27) Acute myocardial infarction:
a) is isolated to the right ventricle in < 5% of casesb) involves the atria in 1-2% of casesc) is due to left anterior descending artery critical blockage in 70% of casesd) is due to right main artery critical blockage in 10% of casese) 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) ultra structural cellular features of irreversible damageb) the appearance of “wavy” fibresc) staining defects in preparations with tetrazolium dyed) the appearance of classical features of coagulative necrosise) none of the above
29) The MOST frequent complication of acute myocardial infarction is:
a) cardiogenic shockb) thromboembolismc) congestive cardiac failured) arrhythmiae) deep venous thrombosis
30) Of the following complications of acute myocardial infarction, the MOST frequently occurring is:
a) ventricular ruptureb) sudden deathc) pulmonary oedemad) cardiogenic shocke) thromboembolism
31) Subendocardial myocardial infarction:
a) is reliably predicted by the absence of Q waves on the ECGb) is usually associated with diffuse coronary atherosclerosisc) is associated with plaque rupture without thrombosisd) is associated with vessel thrombosis, but not plaque rupturee) is usually associated with plaque rupture and overlying thrombosis
32) Sudden cardiac death:
a) is most frequently due to ventricular wall ruptureb) is most frequently due to aortic stenosisc) is often the first clinical manifestation of ischaemic heart diseased) is rarely associated with single vessel critical coronary artery stenosise) is associated with acute myocardial infarction in 90% of cases
33) Which is the MOST frequent cardiac valve abnormality?
a) mitral stenosisb) mitral incompetencec) aortic incompetenced) aortic stenosise) 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) fevers and pan systolic apical murmurb) fevers and a raised ASO titrec) migratory polyarthritis and subcutaneous nodulesd) fever and raised ESRe) a raised ASO titre, pan systolic murmur and migratory polyarthritis
35) Abdominal aortic aneurysms:
a) usually involve the renal arteriesb) usually involve the iliac arteriesc) are more common in post menopausal women than men of the same age groupd) are familiale) 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) systemic lupus erythematosisb) renal failurec) traumad) post myocardial infarctione) bacterial infection
37) The MOST common cause of pericarditis is:
a) SLEb) drug hypersensitivityc) traumad) post myocardial infarctione) bacteria
38) The MOST common pathogens of infective endocarditis are:
a) staphylococcalb) enterobacteriaceaec) streptococcald) chlamydiale) fungal
39) All of the following are features of rheumatic fever EXCEPT:
a) carditisb) subcutaneous nodulesc) erythema nodosumd) elevated antistreptolysine) Aschoff bodies in the heart
40) Abdominal aortic aneurysms:
a) do not develop before the age of 50b) are not familialc) are most common in womend) with a diameter ≤ 4cm have a risk of rupture of 2% per yeare) 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 afternoonb) 30% of myocardial infarcts are “silent”c) an eccentric atherosclerotic plaque is more likely to rupture than a circumferential
oned) atherosclerotic plaque rupture with overlying thrombosis will progress to infarction
if left untreatede) 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) abdominal aortab) coronary arteryc) internal carotid arteryd) popliteal arterye) middle cerebral artery
43) Which of the following is the LEAST significant risk factor for atherosclerosis?
a) obesityb) hypercholesterolaemiac) hypertensiond) diabetese) cigarette smoking
44) A major risk factor that predisposes towards atherosclerosis is:
a) male genderb) diabetesc) obesityd) family history of premature atherosclerosise) physical inactivity
45) Atheroma predominantly effects:
a) the intimab) the mediac) the adventitiad) the media and adventitiae) the whole arterial wall
46) The foam cells in atherosclerotic lesions are:
a) intimal cells full of lipidb) monocytes full of lipidc) smooth muscle cells that have migrated from the media to the intimad) platelets that are adherent to the plaque
47) Which is NOT a feature of atheromatous plaques?
a) it mainly involves the muscular and elastic arteriesb) lesions tend to be covered with a fibrous cap of smooth muscle cellsc) the edges (“shoulder”) contain macrophages and T-cellsd) the core is a necrotic mass of cholesterol and other lipids with foam cellse) it mainly occurs within the tunica media
48) After the abdominal aorta, in general, which site is the most heavily effected by atheroma?
a) descending thoracic aortab) coronary arteriesc) popliteal arteryd) internal carotid arterye) vessels of the Circle of Willis
49) The hyperlipidaemic contribution to the pathogenesis of atheroma is thought to occur via:
a) atheroma macrophages uptaking lipid via LDL receptorsb) hyperviscosity secondary to hyperlipidaemiac) oxidation of lipids within the atheromad) the thrombogenic nature of lipidse) apolipoprotein B-48
50) Regarding haemorrhagic infarction of the brain, which of the following is NOT true?
a) it usually results from an embolic eventb) it usually contains multiple petechial haemorrhages which may be confluentc) the distinction between this and non haemorrhagic infarcts is clinically
insignificantd) the haemorrhages are presumed to be secondary to reperfusion injurye) 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) common carotid arteryb) internal carotid arteryc) the heartd) either end of basilar arterye) intra-cranial vessels
Section 1
Cardiovascular – Answers
1 C2 A3 E4 C5 D6 E7 C8 E9 C10 D11 B12 E13 E14 C15 E16 E17 C18 A19 D20 B21 E22 D23 A24 C25 D26 E27 A28 B29 D30 C31 B32 C33 D34 C35 D36 D37 D38 C39 C40 D41 C
42 A43 A44 B45 A46 B47 E48 B49 C50 C51 C
Section 2
1) Which is NOT a compensatory change in congestive heart failure?
a) myofibre hypertrophyb) myofibre stretchc) bradycardiad) blood volume expansione) ventricular dilatation
2) Which is NOT a cause of pure right sided heart failure?
a) tricuspid valvular diseaseb) pulmonary embolusc) COADd) hypertensione) myocarditis
3) Which is a major (Jones) criteria for rheumatic fever?
a) erythema nodosumb) feverc) past history of rheumatic feverd) raised ESRe) polyarthritis
4) Which endothelial product is prothrombotic?
a) prostacyclinb) thrombomodulinc) plasminogen activatord) heparin-like moleculese) tissue-factor
5) Blockage of the left circumflex artery will cause infarction in:
a) anterior left ventricleb) posterior septumc) lateral left ventricled) apex
e) right ventricle
6) Morphological changes in an acute myocardial infarction include:
a) coagulative necrosis within 1 hourb) ATP 10% of normal within 10 minutesc) yellow soft demarcated area within 3-10 daysd) new blood vessel formation at 3 dayse) loss of contractility within 5 minutes
7) What organism most commonly causes SBE?
a) staphylococcus aureusb) staphylococcus epidermidisc) group A streptococcusd) α haemolytic streptococcuse) haemophilus
8) Regarding aortic dissection:
a) there is a blood-filled channel along the laminar planes of the intimab) hypertension is present in 75% of casesc) is mostly in 40-60 year old womend) there is marked dilatation of the aortae) is unusual in severe atherosclerosis
9) Which is a major risk factor for atherosclerosis?
a) obesityb) physical inactivityc) stress (type A personality)d) hypertensione) homocysteine
10) Which vessel is least likely to develop atherosclerosis?
a) mesenteric arteryb) Circle of Willisc) descending thoracic aortad) internal carotid arterye) popliteal artery
11) Bicuspid aortic valve – which is FALSE?
a) incidence is 1-2%b) no increased predisposition to aortic stenosisc) increased association of coarctation and dissectiond) increased risk of infective endocarditise) increased risk of valve incompetence
12) Major Jones criteria for rheumatic fever include:
a) feverb) previous rheumatic feverc) ESR > 20d) prolonged PR interval on ECGe) polyarthritis
13) Hypertension is a risk factor for all EXCEPT:
a) renal failureb) heart failurec) ischaemic heart diseased) aortic stenosise) cerebrovascular accident
14) Aortic dissection:
a) most common in 40-60 year old femalesb) are most frequently associated with aneurysms c) extend along the intimal plane of the aortad) usually occur 2cm from the aortic valvee) type A involves the great vessels of aortic arch
15) An anticoagulant produced by endothelium is:
a) thrombomodulinb) factor III (vWF)c) plasminogen activator inhibitord) endotheline) interleukin-6
16) Endothelial cells:
a) have many pinocytic vesiclesb) form junctional complexesc) contain Weibel-Palade bodiesd) elaborate von Willebrand factore) have all of the above characteristics
17) The cardothelium does not:
a) serve as a semi-permeable membraneb) migrate to the media in response to injuryc) regulate thrombosis, thrombolysis and platelet adherenced) regulate leukocyte interactions with vessel walle) metabolise hormones
18) The endothelium does not:
a) have many synthetic propertiesb) have many metabolic propertiesc) maintain the non-thrombogenic blood tissue interfaced) constrict to reduce flow in response to drugs or hormonese) modify lipoproteins in the arterial wall
19) Endothelial cells are not activated by:
a) cytokinesb) high PCO2 c) bacterial productsd) hypoxiae) haemodynamic forces
20) Endothelial cells do not elaborate:
a) prostacyclin and NO/EDRFb) plasminc) heparin-like moleculesd) endothelin and ACEe) extracellular matrix
21) Which of the following forms of vasculitis does not involve glomeruli?
a) Henoch Schoenlein purpurab) Wegeners granulomatosusc) polyarthritis nodosad) Goodpasturese) SLE
22) Which of the following vasculilides is associated with a raised pANCA?
a) rocky mountain spotted feverb) drug inducedc) rheumatoidd) cryoglobulinaemiae) Churg Strauss
23) In which of the following groups of vasculitis is the pathogenesis well defined?
a) Takayasu pulseless diseaseb) microscopic polyangiitisc) polyarthritis nodosad) giant cell arteritise) 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 valvesd) mitral regurgitation is the most frequent of all valvular abnormalitiese) 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 casesc) EBV is a common cause of viral myocarditisd) giant cell myocarditis has a relatively good prognosise) 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 ischaemiac) the right coronary artery supplies the ventricular septumd) coagulative necrosis begins within 24 hours of a myocardial infarctione) myocardial infarctions are silent in 5% of cases
27) Regarding atherosclerosis:
a) fatty streaks cause disturbance in blood flowb) fatty streaks appear in aortas of all children older than one yearc) atheromatous plaques are composed of a luminal surface of foam cellsd) coronary artery lesions are often mainly fatty atheromase) the lipid in a plaque is primarily triglyceride
28) After the abdominal aorta, the next most affected vessel with atherosclerosis is:
a) Circle of Willisb) thoracic aortac) axillary arteryd) popliteal arterye) internal carotid artery
29) Major modifiable risk factors for atherosclerosis include:
a) ageb) type A personalityc) increased plasmo homocysteined) diabetes mellituse) physical inactivity
30) Regarding cellular depletion of ATP in myocardial infarction:
a) 10% at 10 minutesb) 50% at 20 minutesc) there is no ATP in myocytesd) 10% at 40 minutese) 50% leading to irreversible injury
Section 2
Answers
1 C2 D3 E4 E5 C6 C7 D8 E9 D10 A11 B12 E13 C14 E15 A16 E17 B18 D19 B20 B21 no answer22 no answer23 no answer24 no answer25 no answer26 no answer27 no answer28 no answer29 no answer30 no answer
Section 3
1) Which of the following is not a primary cause of diastolic dysfunction?
a) massive left ventricular hypertrophyb) myocardial fibrosisc) aortic regurgitationd) deposition of amyloide) constrictive pericarditis
2) At autopsy, the heart of patients having CHF is characterised by all of the following EXCEPT:
a) increased weightb) increased capillary densityc) progressive wall thinningd) chamber dilatatione) microscopic changes of hypertrophy
3) Left-sided heart failure is most often caused by the following, EXCEPT:
a) ischaemic heart diseaseb) hypertensionc) aortic and mitral valvular diseased) myocardial diseasese) pulmonary diseases
4) The most common cause of IHD syndrome is:
a) stenosing coronary atherosclerosisb) intraluminal thrombosisc) rupture or fissure of an atherosclerotic plaqued) platelet aggregatione) coronary vasospasm
5) Compensatory vasodilation is not sufficient to meet increased myocardial demand, beyond an obstruction of a major coronary artery by:
a) 45%b) 55%c) 65%d) 75%e) 85%
6) Which of the following is not thought to be associated with acute rupture of an atherosclerotic plaque?
a) vasospasmb) tachycardiac) circadian periodicityd) intraplaque haemorrhagee) raised intrathoracic pressure
7) Which of the following is associated with ST segment elevation on the ECG?
a) stable anginab) Prinzmetal’s anginac) Unstable anginad) All of the abovee) None of the above
8) Which of the following is incorrect regarding Q wave infarcts?
a) acute mortality in non-Q wave infarcts is half that in patients with Q wave infarctsb) non-Q wave infarcts have a low early mortality ratec) non-Q wave infarcts have a high late mortality rated) the presence or absence of Q waves reliably predicts the distinction between
subendocardial and transmural infarctse) none of the above
9) What proportion of myocardial infarcts occur in people under the age of 65:
a) 65%b) 55%c) 45%d) 35%e) 25%
10) In the typical right dominant heart, occlusion of the LAD coronary artery will produce an infarct in the:
a) anterior two thirds of the interventricular septumb) lateral wall of the left ventriclec) posterior one third of the interventricular septumd) inferior wall of the left ventriclee) posterior wall of the left ventricle
11) Which is the least common complication of acute myocardial infarction?
a) cardiac arrhythmiab) left ventricular failurec) cardiogenic shockd) rupture of free wall, septum or papillary musclee) thromboembolism
Section 3
Answers
1 no answer2 …..3 ….4 ….5 ….6 ….7 ….8 ….9 ….10 ….11 …..
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 infarction2 Angina pectoris – three types: Stable
PrinzmetalUnstable
3 Chronic ischaemic heart disease with heart failure4 Sudden cardiac death (fatal arrhythmia)
RiskUnmodifiable: gender, family history, age, genetic predisposition, Major: smoking, diabetes mellitus, HT, hypercholesterolaemiaMinor: 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 Role of acute changes in atherosclerotic plaque 3 Role of coronary thrombosis4 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
ThrombosispH adhesion, activation, aggregation (exposed plaque contents and endothelial BM)+ mediators of coagulation leads to fibrin clotconsequences 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
VasoconstrictionSM + by: Circulating adrenergic agonists
Locally released pH contentsInflammation mediatorsDecreased secretion NO by damaged endothelium
Consequences of vasoconstriction Decreased vessel lumen Altered forces in vessel – increased risk plaque rupture
Myocardium is O2 dependent tissueCoronary 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
Pathogenesis1 Fixed coronary obstruction2 Acute plaque change3 Coronary thrombosis4 Vasoconstriction
AnginaCharacterised by paroxysmal and recurrent attacks of precordial chest pain
1 stable angina2 Prinzmetal variant angina3 Unstable angina
Myocardial InfarctionDeath of heart muscleLeading cause of death in industrialised countries
Types1 transmural – full thickness, single a. territory2 subendocardial – inner 1/3 to ½ , extends beyond a. territory
Risk FactorsAs for atherosclerosis:1 major, non-modifiable (age, male, genetic)2 major, modifiable (lipids, HT, cigs, DM)3 other (obesity, inactivity, stress, homocysteine, etc)
Pathogenesis1 atherosclerotic plaque change2 platelet adhesion, aggregation, activation3 other mediators + (2) → extrinsic coagulation4 occlusive thrombus→ cell death throughout anatomic region supplied by a.outcome depends on severity and duration of occlusion
Location1 LAD (40-50%) → ant. LV, ant. Septum, apex2 RCA (30-40%) → inf-post. LV and RV, post. septum3 LCX (15-20%) → lat. LVMorphology
Cellular: Seconds : onset of ATP depletion< 2 min : loss of contractility
Normal coronary a. fixed obstruction(typical angina)
plaque disruption severe fixed obstruction(chronic IHD)
variable obstruction occlusive thrombus(USAP, subendo. MI) (transmural MI)
sudden death
10 min : ATP 50% of normal40 min : ATP 10% of normal (irreversible cell injury)> 1 hour : microvascular injury
Time Light microscopy Gross features0-4 hours subcellular change (EM)4 hours – 3 days coagulative necrosis, haemorrhage, oedema dark mottling1-7 days neutrophils3-10 days macrophages → phagocytosis, granulation yellow-tan & soft7-14 days granulation tissue, new blood vessels red-grey borders2-8 weeks increased collagen, decreased cells grey-white scar
ReperfusionBefore 20 minutes → may prevent all necrosisAfter 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 complicationsDepend on MI size, site and transmural extent
1 contractile dysfunction → LVF, cardiogenic shock2 arrhythmias (s. brady, PVCs, VT/VF, asystole, heart block (inf MI))3 myocardial rupture4 pericarditis5 RV infarction6 infarct extension/expansion7 mural thrombus → embolism8 ventricular aneurysm9 papillary muscle dysfunction → MR10 progressive late CCF
Chronic IHDProgressive heart failure as a result of ischaemic myocardial damage
Sudden Cardiac DeathUnexpected death from cardiac causesCauses: IHD
Other – congenital, valvular disease, cardiomyopathy, conduction, abnormalitiesUltimate cause nearly always VF or asystole
