Cardiology

Question 1

What cardiac murmurs present in the first 24hrs of life?

Answer 1

1. Semilunar valve stenosis (AV/PV)
2. AV valve regurgitation (MR/TR)

NOT: VSD, ASD

Question 2

What CHD causes cyanosis in the first 24hrs of life?

Answer 2

TGA Single ventricle physiology

Question 3

What CHD presents as critically ill in the first 24hrs of life?

Answer 3

Valve regurgitation – especially Ebstein’s [large RA], absent PV Obstructed TAPVD “Early” duct dependent presentation

Question 4

CDH dependent on PDA for pulmonary blood flow

Answer 4

Severe cyanosis when duct closes Critical PS Pulmonary atresia Single ventricle with PS or PA

Question 5

CDH dependent on PDA for systemic blood flow

Answer 5

Low CO when duct closes Critical AS Critical coarctation HLHS

Question 6

CDH dependent on PDA for mixing

Answer 6

TGA

Question 7

CDH that causes massive cardiomegaly in neonate

Answer 7

Ebsteins

Question 8

CDH that causes the snowman sign

Answer 8

TAPVD

Question 9

Asymptomatic murmurs

Answer 9

“Functional” commonest ASD VSD PS + AS (ejection click) Coarctation: murmur best heard at the back PDA

Question 10

What valvular problem is associated with coarctation

Answer 10

Bicuspid aortic valve

Question 11

Can you eliminate a ‘stills murmur’ with positioning?

Answer 11

Yes, ask the child to sit on the bed with their neck hyperextended + propped up on their arms positioned behind them

Question 12

Ficks principle

Answer 12

Total uptake (or release) of a substance by an organ is the product of blood flow to that organ and the concentration difference of the substance in the arteries and veins leading into and out of that organ Key rules 1. The lower the CO the more oxygen is extracted 2. High mixed venous sat = shunt (eg. TAPVR) 3. Low mixed venous sat = low CO Normal mixed venous = 75 (high 60’s-75)

Question 13

Ficks formula

Answer 13

Fick’s method = O2 consumption/ (arterial – venous content difference) → This requires Hb, saturation of O2, O2 binding capacity of Hb and dissolved O2 Qp/Qs = arterial saturation – mixed venous saturation / pulm venous saturation – pulmonary artery saturation QP: QS = 1 no shunt Qp: QS > 2 = large shunt Qp: QS < 1 R to L shunt

Question 14

What is the formula to calculate pulmonary vascular resistance?

Answer 14

PVR (um2) = mean PA pressure - LA pressure / Qp Qp = pulmonary blood flow LA pressure can be inferred by using PCWP (pulmonary capillary wedge pressure) IF there is no shunt you can use CO as a surrogate for Qp 1-2 = normal 2-4 = mild elevation 4-6 = mod elevation >7.9 = severe, high correlation with irreversible PVR PVR = 1/6th of SVR

Question 15

Criteria to refer VSD to cardiology

Answer 15

Heart failure FTT Dominant RVH on ECG (suggests tetralogy or variant) Isolated LVH (suggests coarctation or PDA) Aortic regurgitation Qp/Qs > 2: indication to close

Question 16

Classic triad of symptoms in aortic stenosis

Answer 16

Chest pain Shortness of breath Syncope

Question 17

Normal pressures in the heart

Answer 17

Right atrium (mean) 2-8 Right ventricle (peak) 17-32 Pulmonary artery (mean) 9-19 >25 = PHTN Left atrium (mean) 2-12 Left ventricle (peak) 90-140 Aorta (mean) 70-105

Question 18

Pulmonary hypertension

Answer 18

Mean PA pressure > 25mm Hg at rest Mean PA pressure > 30mm Hg with exercise

Question 19

What is the formula for cardiac output + what are the methods of measurement (direct vs indirect)?

Answer 19

CO = HR x SV Normal CO varies with age (higher in newborns) Children 4-5L/min/m2 In the absence of any shunt, pulmonary flow + CO are the same Direct measurement = thermodilution, indicator dye dilution Indirect measurement = fick method (requires estimation of O2 consumption)

Question 20

Is clinical cyanosis noted earlier in anaemia or polycythaemia?

Answer 20

Polycythaemia Cyanosis is recognised at a higher level of O2 saturation in polycythaemia (80-85%) and low level of saturation in anaemia (45-50%) Clinical cyanosis is reached when level of reduced HgB reaches 5g/100mL (normal = 2g /100mL)

Question 21

What factors increase PVR?

Answer 21

Hypoxia Hypercapnia Increased sympathetic tone Polycythaemia Pulmonary emboli Pulmonary oedema Lung compression (effusion)

Question 22

What factors reduce PVR

Answer 22

Oxygen Adenosine Inhaled NO Prostacyclin Ca channel blockers

Question 23

% of CHD associated with extra cardiac anomalies

Answer 23

10-15%

Question 24

Risk of recurrence of CHD in siblings

Answer 24

2-4 % Further increased risk if > 1 sibling affected or if maternal history

Question 25

Diagnostic criteria for Kawasaki disease

Answer 25

WARM CREAM Fever for \> 5 days AND 4 out of 5 of the following Conjunctivitis (bilateral, dry or non-purulent, preferentially in bulbar distribution) Rash (Polymorphous, without vesicles, bullae or crusts, occurs in the first few days. Variable such as urticarial morbilliform, maculopapular or resembling scarlet fever) Extremity changes (hyperaemia and painful oedema of hands and feet that progresses to desquamation in the convalescent stage; perianal desquamation) Adenopathy (cervical, most commonly unilateral, tender, at least one node \>1.5cm) Mucosal involvement (intense hyperaemia of lips leading to redness and cracking and/or diffuse erythema or oropharynx; strawberry tongue)

Question 26

Kawasaki disease fast facts

Answer 26

2nd most common vasculitis in childhood after HSP Most common cause of acquired heart disease in children 85% of cases \< 5yrs (peak 18-24 months) Rare in children \< 6 months + \> 5yrs BUT more likely to develop CAA More common in Asian population 15-25% develop CAA if untreated compared to 4% if treated with IVIG CAA rarely occurs before day 10

Question 27

Incomplete Kawasaki disease criteria

Answer 27

Children with fever for 5 days + 2 clinical criteria OR fever for 7 days without explanation AND - CRP \> 8 + ESR \> 20 AND 3 or more: - Anaemia - Plt \> 450 after 7th day of fever - Albumin \< 30 - Raised ALT - WCC \> 15 - Urine \> 10 WBC/hpf OR positive echo

Question 28

Management of rheumatic heart disease

Answer 28

Rest, fluid restriction Diuretics ACEI for afterload reduction if aortic regurgitation Digoxin for SVT No literature evidence for use of corticosteroids and IVIG. However, corticosteroids used commonly if severe

Question 29

Diagnostic criteria of rheumatic fever

Answer 29

Evidence of strep A infection (elevated or rising ASOT or anti-DNAseB or positive throat culture / rapid antigen / PCR test) AND 2 major OR 1 major + 2 minor MAJOR Joints (polyarthritis or aseptic monoarthritis or polyarthralgia. Usually migratory + asymmetical). Large joints most commonly affected; especially knees + ankles. Should respond to NSAIDs. HEART (carditis, subclinical evidence of rheumatic valvulitis on echo) Nodules (subcutaneous, extensor surfaces). Very rare \<2% of cases BUT highly specific. Round, firm, mobile + painless. Strongly associated with carditis. Erythema marginatum. Very rare \<2% of cases BUT highly specific. Sydenham chorea (jerky, uncoordinated movements). Predominately affects females in adolescence. Disappears in sleep. MINOR PR prolongation Elevated temperature Arthralgias CRP \> 30 ESR \> 30

Question 30

Antibiotic treatment for strep A sore throat / tonsillitis

Answer 30

Benzathine benzylpenicillin IM once OR Phenoxymethylpenicillin 15mg/kg BD for 10 days OR Cefalexin 25mg.kg BD for 10 days OR Azithromycin 12mg/kg daily for 5 days

Question 31

What are the upper limits of normal for PR interval?

Answer 31

3-11yrs 0.16 12-16yrs 0.18 17+yrs 0.2

Question 32

Fast facts about sydenham chorea

Answer 32

- May occur after a prolonged latent period following strep A infection (must exclude SLE or chorea gravidarum first) - Diagnosis of ARF can be made without the presence of other manifestations or elevated plasma strep antibody titres if chorea present - ARF manifestation that is most likely to reoccur - May occur in pregnancy or with OCP use - Majority of cases resolve within 6 months - Higher prevalence of ADHD, anxiety, depression + cognitive dysfunction after recovery

Question 33

Predominantly manifestation of ARF carditis

Answer 33

Myocarditis and pericarditis may occur in ARF however, the predominant manifestation of carditis is the involvement of the endocardium presenting as a valvulitis, especially of the mitral and aortic valves. The incidence of carditis in initial attacks of ARF varies between 30% and 82%

Question 34

What valve does ARF commonly affect?

Answer 34

Valvulitis most commonly affects the mitral valve, leading to mitral regurgitation (MR), although with prolonged or recurrent disease scarring, may lead to stenotic lesions. MR presents clinically as an apical blowing, holosystolic (pansystolic) murmur. The presence of an associated mid-diastolic flow murmur (Carey Coombs murmur) implies significant mitral valve regurgitation; however, it must be differentiated from the diastolic murmur of mitral stenosis (MS), which is often preceded by an opening snap

Question 35

Serum ASO + anti-DNAse B titres: time to reach maximum levels

Answer 35

Serum ASO titre rises within 1-2 weeks, and reaches a max at 3-6 weeks Serum anti-DNase B titre up to 6-8weeks to reach a maximum

Question 36

Strep A (streptococcus pyogenes) susceptibility to antibiotics

Answer 36

Almost universally susceptible to penicillin and related beta lactam antibiotics, e.g. cephalosporins. The organism appears to lack capacity to express beta lactamase that would confer resistance.16 Mutations in penicillin-binding proteins conferring decreased susceptibility to some beta lactam antibiotics but not penicillin have been reported. Strep A can, however, readily become resistant to macrolide antibiotics (azithromycin, roxithromycin, erythromycin etc) with marked geographical variation. Resistance to macrolide antibiotics generally also confers resistance to clindamycin.

Question 37

What is sydenham chorea and how is it treated?

Answer 37

Sydenham chorea is a neuropsychiatric manifestation of ARF characterised variably by chorea, decreased muscle tone, and psychiatric and behavioural symptoms such as obsessivecompulsive symptoms and hyperactivity. Treatment - Supportive - Carbamazepine or sodium valproate - If very severe can add in risperidone, haloperidol, corticosteroids or IVIG, plasma exchange

Question 38

Screening tests required prior to immunosuppressive doses of steroids

Answer 38

Tuberculosis: interferon gamma release assay or Tuberculin Skin Test (TST/Mantoux test) Hepatitis B: Hepatitis B serology with HBsAg, HBcAb and HBsAb. In patients with either a positive HBsAg or HBcAb, a hepatitis B DNA PCR should be ordered Hepatitis C: Hepatitis C antibody. If positive, an HCV RNA viral load and genotype should be ordered HIV serology Melioidosis: Strongyloidiasis: Serology and if serology is positive or eosinophilia is present, also perform stool microscopy (single stool as a minimum, but 3 preferable). Treat with ivermectin Scabies Review of immunisation history

Question 39

What is secondary prophylaxis of ARF

Answer 39

Consistent and regular administration of antibiotics to people who have had ARF or rheumatic heart disease (RHD), to prevent future group A betahaemolytic streptococcus (Strep A) infections and the recurrence of ARF

Question 40

What is the antibiotic regimen for secondary prophylaxis of ARF?

Answer 40

1st line Benzathine benzylpenicillin G IM every 28 days 2nd line Oral phenoxymethylpenicillin BD Penicillin allergy Oral erythromycin BD

Question 41

Duration of antibiotic prophylaxis in ARF

Answer 41

Possible ARF 12 months then reassess Probably ARF Min 5yrs then reassess Definite ARF (whichever is later0 Mild: min 10 yrs or until 21 Mod: min 10 yrs or until 35 Severe: min 10 yrs or until 40

Question 42

Mechanical valve vs bioprosthetic valve

Answer 42

Mechanical valve: proven durability, requires lifelong anticoagulation Bioprosthetic valve: does not require lifelong anticoagulation, limited durability, may enable future valve in valve procedure

Question 43

Definition of infective endocarditis

Answer 43

Infection of the endocardium +/or heart valves that involved thrombus formation (vegetation)

Question 44

Common organisms in infective endocarditis - WITH underlying heart disease - WITHOUT underlying heart disease

Answer 44

Among children with underlying heart disease: •Viridans streptococci – 33 percent •Staphylococcus aureus – 28 % •Other streptococci – 17 % •Polymicrobial – 11% •Other Staphylococcus species – 7% •Gram-negative bacilli – 5 % ●Among children without underlying heart disease: •S. aureus – 47% •Viridans streptococci – 18 % •Other streptococci – 10 % •Gram-negative bacilli – 8 % •Other Staphylococcus species – 6% •Polymicrobial – 12% \*\*Blood cultures negative in 5-7% of cases\*\*

Question 45

Pathogenesis steps in infective endocarditis

Answer 45

1. Endothelial damage: turbulent flow or mechanical damage to the endothelium 2. Thrombus formation: deposition of fibrin, plts + RBC forming non-infected thrombus 3. Transient bacteraemia or fungaemia- adherence of microbial pathogens to the injured endocardium + thrombus 4. Infected vegetation- further fibrin + plt deposition result in a protective sheath that isolated the organism from host defences and permits rapid proliferation 5. Other organ involvement- secondary embolisation or immune mediated processes (e.g. glomerulonephritis, brain abscess)

Question 46

Symptoms dependent on clinical features in infective endocarditis

Answer 46

Bacteraemia- fever, tachycardia, vasodilation Valvulitis- murmur, tachycardia, vasodilation Immunologic- roth spots, janeway lesions, osler nodes Septic emboli- osteomyelitis, pneumonia

Question 47

Outline Duke's criteria for endocarditis

Answer 47

2 major OR 1 major 3 minor OR 5 minor MAJOR - Typical microorganism from x 2 blood cultures OR single BC with coxiella burnetii - Persistently positive blood cultures (2 BC drawn \>12hrs apart) - Evidence of endocardial involvement: vegetation OR abscess OR new partial dehisence of prosthetic valve OR new valvular regurgitation MINOR - Risk factor - Fever - Vascular phenomena (janeway lesions, conjunctival haemorrhage, emboli, aneurysm, intracranial haemorrhage) - Immunologic phenomena (GN, osler node, roth spots, rheumatoid factor) - Microbiologic evidence

Question 48

How is TOE superior to TTE in infective endocarditis

Answer 48

TOE is superior to TTE for the detection of aortic root abscess

Question 49

In pulmonary HTN (PAP \>25mmHg), what is the cause IF The PCWP is low / normal (\<15mm Hg) OR The PCWP is elevated (\>15 mm Hg)

Answer 49

PCWP low / normal = pulmonary vascular disease (aka pulmonary arterial hypertension) PCWP elevated = likely secondary to heart problem (aka pulmonary venous hypertension)

Question 50

What is the formula for systemic vascular resistance?

Answer 50

Ao - RA / Qs

Question 51

Outline pulmonary hypertension management

Answer 51

Diuretics: symptoms of fluid retention Oxygen: mortality benefit for group 3 Anticoagulation: group 4 Exercise training

Question 52

Where would the intracardiac shunt be in the following examples? Increase in O2 [] in RA Increase in O2 [] in RV Increase in O2 [] in PA

Answer 52

Increase in O2 [] in RA - ASD. DDx PAPVC, cor fistula to RA Increase in O2 [] in RV - VSD. DDx cor fistula to RV Increase in O2 [] in PA - PDA

Question 53

Types of ASD

Answer 53

Ostrium primum = partial AVSD (15-20%) more common in T21 Ostium secundum 75%. More common in females. Sinus venosus (5-10%) not a true ASD. SVC (most common) + IVC types. Associated with anomalous pulmonary venous return

Question 54

When to close and when to NOT close an ASD

Answer 54

When to close: Symptomatic RV enlargement Qp:Qs \> 1.5 Paradoxical embolism Platypnea- orthodeoxia syndrome When not to close: Eisenmenger

Question 55

Size of ASD + likelihood of closure

Answer 55

ASD \< 5mm = close ASD 5-8 = likely close if no RV dilation ASD \>8mm = need surgical closure Usually transcatheter device closure unless large

Question 56

ASD murmur charachteristics

Answer 56

Splitting of S2 Ejection systolic Mid diastolic murmur due to increased flow across the tricuspid valve

Question 57

Is heart failure in children most commonly LEFT, RIGHT or biventricular?

Answer 57

Biventricular due to ventricular interdependence

Question 58

Indications for endocarditis prophylaxis with dental procedures

Answer 58

Prosthetic cardiac valve Previous IE CHD IF it involved unrepaired cyanotic defect (including palliative shunts + conduits) Repaired CHD with prosthetic material for the first 6 months post procedure RHD in indigenous Aus Cardiac transplant recipients

Question 59

At risk procedures for IE that require prophylaxis

Answer 59

Dental procedures that involve manipulation of gingival tissue Invasive resp procedures (tonsillectomy / adenoidectomy) Invasive GI / GU procedures I + D of abscesses Surgical procedure through infected skin

Question 60

IE antibiotic prophylaxis

Answer 60

Amoxicillin 50mg/lg oral 1 hr before procedure OR clindamycin 15mg/kg 1 hr before procedure

Question 61

What cardiac complication is MOST likely to develop in Duchenne muscular dystrophy?

Answer 61

Dilated cardiomyopathy

Question 62

Murmur in tetralogy of fallot

Answer 62

Harsh ejection systolic LSE Radiates through to the back Loud single S2 due to inaudible P2 closure sound

Question 63

Tetralogy of fallot associations

Answer 63

T21 22q11

Question 64

Tetralogy of fallot ECG + CXR findings

Answer 64

ECG RV hypertrophy CXR Boot shaped Up-tilted apex Reduced lung vascularity

Question 65

Lesions is tetralogy of fallot

Answer 65

Overiding aorta RVH VSD PS (often associated with infundibular muscular obstruction)

Question 66

Cardiac shape + CHD association - Boot shaped - Egg shaped - Sitting duck - Snowman

Answer 66

- Boot shaped = tetralogy of fallot - Egg shaped = incorrected transposition - Sitting duck = truncus arteriosus - Snowman = supracardiac TAPVD

Question 67

Ossification of bones

Answer 67

'CRITOE" Capitellum Radial head Internal epicondyl Trochlear Olecranon External epicondyl 1, 3, 5, 7, 8, 11, ish

Question 68

What extra feature do you look for on a CXR in a patient with T21?

Answer 68

11th rib

Question 69

What is the most common CHD in T21?

Answer 69

AV canal defect * Superior axis * Usually no murmur 75% of patients with an AV canal defect have T21 Usually complete AV canal defect

Question 70

What are the features of of pulmonary plethora on CXR and at what point do you see it?

Answer 70

* Enlarged central and peripheral pulmonary arteries * "DOTS" in the peripheral lung fields * Lateral film show large pulmonary arteries CXR findings of pulmonary plethora only present when Qp:Qs \> 2:1

Question 71

What % of patients with Patau have CHD?

Answer 71

80%

Question 72

What % of patients with Edwards have CHD?

Question 73

What % of patients with Turner's Syndrome (XO) have CHD? What is the most common defect?

Answer 73

35%

Question 74

What % of patients with Klinefelter 47XXY have CHD?

Question 75

What is the most common CHD in 22q.11

Answer 75

Tetralogy of Fallot

Question 76

What is the most common CHD in Williams?

Answer 76

Supravalvular aortic stenosis

Question 77

What is the most common CHD in Noonan syndrome?

Question 78

What are the ECG findings in AVSD?

Answer 78

Turner's syndrome

Question 79

Answer 79

Tetralogy of Fallot is most likely which is associated with DiGeorge

Question 80

Answer 80

22q11 They have truncus arteriosus therefore most common with 22q11

Question 81

Answer 81

Noonan's syndrome Pulmonary valve stenosis

Question 82

Answer 82

Velocardial facial syndrome / 22q11

Question 83

T21 who is cyanotic most common diagnosis

Answer 83

Tetralogy of fallot

Question 85

What are the ECG findings in AVSD?

Answer 85

* Left axis deviation * RA enlargemtn * Biventricular hypertrophy * Incomplete RBBB