Heart Disorders 2 Flashcards
(118 cards)
1
Q
Preductal coarctation is associated with what congenital heart defects?
A
VSD & Turner syndrome
2
Q
Post ductal coarctation of aorta is common in which age group?
A
Children> adults
3
Q
What is cause of death in preductal coarctation of aorta?
A
CHF
4
Q
Why are patients suffering from post ductal coarctation at an increased risk to develop aortic dissection & berry aneurysm?
A
Construction distal to ligament in arteriosum-increased blood flow to subclavian artery & upper extremity-dilation of aorta-aortic dissection
Berry aneurysm-increased blood flow to brain
5
Q
Why is there a difference of >10mm Hg in blood pressure between upper extremity & lower extremity in post ductal coarctation?
A
Constriction distal to ligament in arteriosum-increased blood volume to subclavian artery & upper extremity-decreased blood volume to lower extremity
6
Q
Why is there leg claudication in post ductal coarctation?
A
Decreased blood volume to lower extremities-under developed musculature as compared to upper extremities
7
Q
Why is there hypertension in post ductal coarctation?
A
Decreased blood flow to kidneys-activation of renin-angiotensin-aldosterone system-hypertension
8
Q
How is blood flow maintained via collaterals in post ductal coarctation?
A
Internal mammary & subclavian artery
Superior epigastrium & inferior epigastrium artery
9
Q
Why is there rib notching in a chest radiograph of a post ductal coarctation of aorta patient?
A
Formation of collaterals-enlarged pulsating internal thoracic artery-wears bone away
10
Q
Why do pharyngeal strains of group A streptococcus only cause rheumatic fever?
A
Posses M protein-virulence factor in cells wall
11
Q
When do patients develop first attack of RF?
A
5-15years
12
Q
Why is RF an example of molecular mimicry?
A
Host develops antibodies against M proteins of group A streptococci-cross react with human tissue (type 2 hypersensitivity reaction)
13
Q
What is the most common initial clinical finding in rheumatic heart fever?
A
Migratory polyartheritis
14
Q
Migratory polyartheritis involves what kind of joints?
A
Large joints-knee, ankle, wrist
15
Q
Types of carditis in RF?
A
Fibrinous pericarditis
Myocarditis-MC death
Endocarditis
16
Q
What are Aschoff bodies?
A
Lesions in myocardial tissue-central area of fibrinous necrosis surrounded by anitschkow cells(reactive histiocytes)
Seen in RF
17
Q
Which valves are most commonly involved in RF?
A
MV>AV>TV
MV regurgitation/AV regurgitation
Recurrent infection-stenosis
18
Q
What are clinical features of RF?
A
- Migratory polyartheritis
- Carditis
- Subcutaneous nodules-extensor surface of forearm, Central fibrinous necrosis
- Sydenham’s chorea
- Erythema marginatum
19
Q
Diagnosis of RF?
A
2 major criteria + 1 minor criteria supported by antecedent pharyngeal group A streptococcus infection
20
Q
Minor criteria for RF?
A
- Fever
- Previous attack of RF
- Arthralgia
- Increased acute phase reactants-ESR, C-reactive protein
- First degree heart block-??
21
Q
Major criteria for RF?
A
Migratory polyartheritis Carditis SC nodules Erythema marginatum Sydenham's chorea
22
Q
Lab tests for RF?
A
ASO titres- >400 Todd units peak: 4-5 week after
Anti-DNAse B titres
Throat cultures
23
Q
Most common type of coarctation?
A
Infantile (preductal) coarctation
24
Q
Most common cause of mitral valve stenosis?
A
RF
25
Why is there dyspnea and rust coloured sputum with hemoptysis in mitral valve stenosis?
Mitral valve stenosis-increased work on LA during filling LV in diastole-hyper trophy and dilation of LA-backing of blood in lungs-increased pressure on pulm capillaries cause rupture-RBC enter alveoli & dyspnea due to congestion
26
Why is there systemic embolisation risk in mitral valve stenosis?
Atrial fibrillation is a complication-stasis of blood in LA-embolisation via aorta in systemic circuit
27
Why is there dysphagia for solids in mitral valve stenosis?
Mitral valve stenosis-increased work imposed on LA during filling of LV in diastole-hypertrophy and dilation-compression of esophagus
28
Why is there pulmonary venous HTN in mitral valve stenosis?
Mitral valve stenosis-pulmonary vein HTN-pulmonary artery HTN-RVH
29
Why is there an opening snap followed by an early-mid diastolic rumble in mitral stenosis?
Thickened valves-open with snap
| Stenosis-increased blood volume in LA-gushes to LV-rumble mid diastolic (filling of ventricle)
30
What is the effect on atrial and ventricular volume and pressure in mitral valve stenosis?
Atrial volume and pressure elevated
| Ventricular volume and pressure decreased
31
Mitral valve stenosis vs. mitral valve regurgitation occur in which phase of cardiac cycle?
Mitral valve stenosis-diastole of ventricle
| Mitral valve regurgitation-systole of ventricle
32
Causes of MV regurgitation?
1. Mitral valve prolapse (MC)
2. LHF-stretching of valve ring (functional MV regurgitation)
3. Rupture/dysfunction of posteromedial papillary muscle post MI
4. Acute RF
33
Why is there eccentric hypertrophy of LA during mitral valve regurgitation?
Volume overload
34
Why is there pulmonary edema and cardiogenic shock in chronic de compensated phase of mitral regurgitation?
Muscle dysfunction-cannot accommodate volume-increases LV and LA pressure-backing up of blood in lungs-pulmonary edema
35
Why is there inspiratory crackles, cough & dyspnea in mitral valve regurgitation?
Increased pressure and volume of LA-backing up of blood in lungs
36
Mitral valve prolapse is commonly associated with which conditions?
Marfans, ehler-danlos, klinefelters
37
Why does mitral valve prolapse occur?
Defective embryogenesis-cells of meaenchymal origin-excess dermatan sulphate in MV leaflet-bulging of anterior & posterior leaflets into LA during systole
38
Why is there a mid systolic click followed by a mid systolic regurgitation murmur in mitral valve prolapse?
Mid systolic click-restraint by chordae tendinae
| Mid systolic rumble-mitral regurgitation-gushing of blood from LA to LV
39
Why does decreased preload cause the murmur of mitral valve prolapse to shift towards s1 & increased preload to s2?
Decreased preload-shortens systole
| Increased preload-prolongs systole
40
Manoeuvres/conditions that shift murmur of mitral valve prolapse towards S1?
Anxiety-increased hr-decreased filling-decreased VR-preload decreased
Standing-decreased VR
Valsalva manoeuver-holding breath with epiglottis closed-+intrathoracic pressure-decreased VR
41
Manoeuvres that shift murmur of mitral valve prolapse towards S2?
Reclining-increased VR-increased preload
Squatting- increased PVR-decreased emptying-increased preload
42
Most common cause of TV regurgitation?
Functional regurgitation due to stretching of ring in RHF
43
Most common cause of TV regurgitation in young adults?
Congenital heart disease
44
Most common cause TV regurgitation in IV drug abusers?
Infective endocarditis affecting TV
45
Why is a pulsating liver found in TV regurgitation?
TV regurgitation-RA dilatation and hypertrophy-back up of pressure in venous system-increased pressure in sinusoids & portal vein
46
What are the effects of back up of pressure in the venous system in a case of TV regurgitation?
1. Pulsating liver
2. Portal hypertension-ascites
3. Dependent pitting edema
47
Why is the pansystolic murmur heard in TV regurgitation increased in intensity on holding deep inspiration?
Check
48
When is graham steell murmur heard?
Pulmonary HTN-stretching of PV ring-functional regurgitation
49
Most common cause of carcinoid heart disease?
Liver metastasis from carcinoid tumour in small intestine to heart
50
Why is the PV stenosis & TV regurgitation in carcinoid heart disease?
Carcinoid heart disease-metastasis of carcinoid tumour in SI to liver-serotonin in hepatic vein-IVC-right heart-serotonin cause fibrosis of PV and TV
51
Most common cause of aortic stenosis in patients >60yrs?
Calcific stenosis (may involve a congenital bicuspid valve)
52
Most common cause of aortic valve stenosis in adults
Congenital heart disease
53
Most common cause for isolated aortic regurgitation?
Aortic root dilatation
54
Causes of aortic valve regurgitation?
1. Infective endocarditis
2. Chronic RF
3. Aortic dissection
4. Dilated AV ring
5. Syphilitic aortitis, aortitis in ankylosing spondylitis & takayasu disease
55
Hyperdynamic signs in chronic AV regurgitation?
Bounding pulse- corrigan water hammer pulse
Head nodding with systole-de musset sign
Pulsating nail bed with elevation of nail-quincke pulse
56
Why is Austin Flint murmur heard in AV regurgitation?
Regurgitation stream from AV hits anterior leaflet of mitral valve
+-indication for replacement
57
Why is a hyper dynamic circulation present in chronic AV regurgitation?
Chronic AV regurgitation-LVEDV increased-LV size increased-DBP decreases-SBP increase-pulse pressure increase
58
Risk factors for infective endocarditis?
1. immunosuppression-HIV,DM
2. dental infections
3. IV catheters, IVDA
4. MVP,AS
5. prosthetic heart valve
59
Staphylococcus aureus is the most common cause of what types of Infective endocarditis?
Acute endocarditis, nosocomial endocarditis, endocarditis in IVDA, endocarditis associated with artificial heart valves (late)
60
Most common cause of subacute endocarditis?
Streptococcus viridans
61
Most common cause of endocarditis due to artificial valves (early
Staphylococcus epidermidis
62
Most common cause of endocarditis associated with ulcerative lesion in colon?
Streptococcus bovis (gallolyticus)
63
Which valves are most commonly affected in IE?
Left sided; mitral valve
64
Which valves are most commonly affected in IVDA with IE?
Tricuspid & aortic valves
65
Why does IE cause valvular vegetations?
Turbulent blood flow-damage to valve-fibrin & platelets adhere to area of damage-trapping of circulating organism-proliferation of pathogens+encasing of pathogens in fibrin-vegetations
66
Why are there regurgitation murmurs in IE?
Vegetations on valve leaflets & chordae tendinae destroy valves-incompetent closing during systole
67
Why are there splinter hemorrhages, janeway lesions & oslers nodes in IE?
Bacteria in micro abscesses-micro embolisation
68
What are splinter hemorrhages? Where are they seen?
Linear haemorrhages in nail bed. Seen in IE
69
What are janeway lesions? Where are they seen?
Painless haemorrhages in palms and soles. Seen in IE
70
What are oslers nodes? Where are they seen?
Painful hemorrhagic nodules on pads of fingers & toes. Seen in IE
71
Why is there glomerulonephritis in IE?
Immune mediated vasculitis that follows microembolisation
72
What are Roth spots? Where are they seen?
Irregular red area with white spot due to immune vasculitis seen in IE
73
Lab findings in acute IE vs. subacute IE?
Acute IE-neutrophil if leukocytosis
| Subacute IE-monocytosis
74
Why is there anaemia in IE?
Anaemia of chronic disease
75
How is IE diagnosed?
Positive blood cultures-3 sets in 24hrs
| Echocardiography-visualise vegetations
76
Ddx of sterile vegetations of valves?
Libman sacks endocarditis
| Nonbacterial thrombotic endocarditis
77
Why is the MV regurgitation seen in SLE patients
Libman sacks endocarditis-sterile vegetations on MV valve
78
Why do mucin producing tumours of colon and pancreas cause non bacterial thrombotic endocarditis?
Procoagulant effect of circulating mucin-sterile non destructive vegetations
79
Drugs causing myocarditis?
SCD-sulphonamides, doxorubicin, cocaine
80
Toxins causing myocarditis?
Diphtheria, toxin from black widow spider & scorpion
81
Bacteria causing myocarditis?
Mycoplasma, borrelia burgdoferi, rickettsia rickettsi
82
Parasites causing myocarditis?
Toxoplasma gondii, trypanosoma cruzi
83
Viruses causing myocarditis?
Adenovirus, coxsackie B virus, HIV
84
Fungi causing myocarditis?
Candida, mucor, aspergillus
85
Causes of myocarditis?
1. Infections
2. Drugs
3. Toxins
4. Systemic collagen diseases
5. Acute RF
6. Sarcoidosis
86
What findings are highly predictive of viral etiology in myocarditis?
Focal area of necrosis with lymphocytic infiltrate
87
Why is there dyspnea in myocarditis?
Myocarditis-global enlargement of heart-dilatation of chambers-volume overload-backing up of blood in pulmonary vessels-edema-dyspnea
88
Clinical features of myocarditis?
Arrhythmias, biventricular heart failure, chest pain, fever, pericardial friction rub (associated pericarditis), Murmurs due to MV regurgitation
89
Why is MV regurgitation seen in patients with myocarditis?
Dilatation of all chambers of heart-volume overload-stretching of mitral valve ring-MV regurgitation
90
Diagnosis of Myocarditis?
CK-MB
Troponin I & T
ECG, cardiac catheterisation, electrocardiogram
91
Most common cause of pericarditis?
Idiopathic
92
How can pericardial friction rub be differentiated from pleural friction rub?
Pericardial friction rub does not disappear on holding breath
93
Why is kussmaul sign seen in pericardial effusion?
Kussmaul sign-on inspiration, neck vein distension.
| On inspiration-VR increases-pericardial effusion decreases RA filling-blood reflux into internal jugular vein
94
Why is pulsus paradoxus seen in patients with pericardial effusion?
Inspiration-VR increases-IVS pushed to left-decreaases LV volume-stroke volume decreases-systolic pressure decreased >10mm Hg
95
Characteristic finding in chest radiograph of patient with pleural effusion?
Water bottle configuration with I distinct borders of heart
96
Most common cause of constructive pericarditis?
TB
97
Most common cause of pericarditis in the U.S.?
Idiopathic/surgery
98
Why is pericardial knock heard in constructive pericarditis?
Ventricles hitting thickened pericardium
99
Characteristic chest radiograph in patient with constructive pericarditis?
Dystrophic calcification of parietal pericardium
100
Most common cause of dilated cardiomyopathy?
Idiopathic
| Previous myocarditis-most common known cause
101
Arrhythmias & biventricular heart failure seen in alcohol abuser. What is the cause?
Dilated cardiomyopathy
102
Patients with acromegaly has biventricular heart failure & arrhythmias. What is the cause?
Dilated cardiomyopathy
103
Why is screening of first degree relatives imperative in patient suffering from hypertrophic cardiomyopathy?
Autosomal dominant disorder-misense mutation, substitution of a single amino acid in contractile protein of cardiac sarcomere-familial form most common
104
Most common cause of sudden death in young athletes?
Hypertrophic cardiomyopathy
105
Dilated cardiomyopathy is most common in which age group?
Young adults
106
Sporadic form of hypertrophic cardiomyopathy occurs in which age group?
Elderly
107
Why do arrhythmias occur in hypertrophic cardiomyopathy?
Aberrant myofibrils
108
Why does harsh systolic ejection murmur intensity increase with valsalva manoeuvre & standing up?
Obstruction to blood flow in hypertrophic cardiomyopathy is due to drawing of MV against asymmetrically enlarged IVS-decreasing preload-increases obstruction
IVS hypertrophy>ventricular hypertrophy
109
How can sudden cardiac death be prevented in hypertrophic cardiomyopathy?
SCD-ventricular fibrillation-prevented by implantable defibrillator
110
Why are digitalis & diuretics (drugs used for heart failure) avoided in hypertrophic cardiomyopathy?
Digitalis-increased contractility
| Diuretics-decrease preload-increase obstruction
111
Most common cause of restrictive cardiomyopathy?
Amyloidosis
112
Most common cause of restrictive cardiomyopathy?
Amyloidosis
Fibrosis post open heart surgery
Radiation
113
Most common site of metastasis in heart?
Pericardium
114
Primary tumours of heart?
Cardiac myxoma
| Rhabdomyoma
115
Why does cardiac myxoma simulate MV stenosis?
MC site-LA-ball valve effect obstructs MV
116
Why is transesophaheal USG used to diagnose cardiac myxoma?
MC site of cardiac myxoma is LA-most posterior lay located chamber-best viewed by this method
117
What is Rhabdomyoma of heart associated with?
Tuberous sclerosis
118
Most common primary tumour of heart in children/infants?
Rhabdomyoma
