Paeds Cardio Flashcards
Name the Right to left shunts (blue/cyanotic) in congenital cardiac disease?
Tetralogy of Fallot
Transposition of great arteries
Name the Left to Right Shunts (breathless) in congenital cardiac disease?
Atrial septal defect
Ventricular Septal Defects
Persistent arterial duct
Name the Common mixing (breathless and blue) in congenital cardiac disease?
Atrioventricular septal defects
What are the symptoms of HF in children?
Breathlessness (particularly on feeding and exertion)
Sweating
Poor feeding
Recurrent chest infections
What are the signs of HF in children?
Poor weight gain of faltering growth Tachypnea Tachycardia Heart murmur Enlarged heart Hepatomegaly Cool peripheries
What cardiac changes that occur during birth?
In the fetus the left atrial pressure is low, as relatively little blood returns from the lungs.
The pressure in the right atrium is higher than in the left, as it receives all the systemic venous return including blood from the placenta
The flap valve fo the foramen ovale is held open, blood flows across the atrial septum into the left atrium and then into the left ventricle which pumps blood to the upper body.
With the first breaths resistance to pulmonary blood flow falls and the volume of blood flowing through the lungs increased 6 fold.
Causes a rise in left atrial pressure
Volume returning to right atrium falls as placenta is excluded from circulation.
The change is a pressure difference causes the flap valve of the foramen ovale to be closed.
The ductus arteriosus which connects the pulmonary artery to the aorta in foetal life will normally close within the first few hours to days.
Some babies who rely on blood flow through the duct (duct dependent circulation)
Give some common causes of congenital disorders
Maternal disorders:
Rubella
SLE
SM
Maternal Drugs :
Warfarin
Foetal alcohol syndrome (ASD, VSD, TOF)
Chromosomal T21 (downs) Atrioventricular septal defect and VSD
Where do you hear a ventricular septal defect?
Pansystolic murmur in lower left sternal border
Where do you hear coarctation of the aorta?
Crescendo-decrescendo murmur in the upper left sternal border
Where do you hear a patent ductus arteriosus?
Diastolic machinery murmur in the upper left sternal border
Where do you hear pulmonary stenosis?
Ejection systolic murmur in the upper left sternal border
RFs for tetralogy of fallot?
Males
Tetragons: Alcohol, Warfarin, Trimethadione
Genetics: Charge syndrome & Digeorge syndrome
What are the 4 features of ToF?
A large VSD
Overriding aorta with respect to the ventricular septum
Subpulmonary stenosis causes right ventricular outflow tract obstruction
Right ventricular hypertrophy as a result
What is the pathology behind the 4 features of ToF?
Ventricular septal defect:
Causes systolic pressure between the ventricles to equalise
Pulmonary stenosis
Commonest site = infundibular septum
Results in impaired flow of deoxygenated blood into the main pulmonary artery
May be severe enough to cause intermittent right ventricular outflow tract obstruction - this forms the basis of the hypoxic episodes, commonly known as tet spells
Right Ventricular hypertrophy
Occurs in response to the high pressure → to overcome it
Can be seen as ‘the boot sign’ in chest x rays
Overriding aorta
Dilated and displaces over the interventricular septum
Aortic dilatation is caused by an increase in blood flow through the aorta as it receives blood from both ventricles vias the VSD.
What are the severities of ToF?
Mild (Pink TOF):
These infants have mild PS/RVH and are usually asymptomatic
However the disease normally progresses as the child and the heart grows
Ny 1-13 they will develop severe cyanosis.
Moderate - Severe (Cyanotic TOF):
Infants born with moderate -severe PS may present within the first few weeks with cyanosis and respiratory distress
Develop recurrent chest infections and fail to thrive
Extreme:
TOF with pulmonary atresia and absent pulmonary valve
These are true ‘duct dependent lesions’ as the only way deoxygenated blood can flow into the lungs is through the patent ductus arteriosus (PDA)
Will present within few hours of life if not detected antenatally
What are tet spells?
Peak age of incidence is usually between 2-4 months of life
Paroxysm of hyperpnea:
a) Rapid deep respirations secondary
b) Due to increased right-to-left shunting, carbon dioxide accumulates therefore stimulating the central respiratory centre
c) Self perpetuating (causes more right to left shunting)
Irritability - manifested by prolonged unsettled crying
Increased cyanosis
May be precipitated by dehydration, anaemia or prolonged crying (induces tachycardia and reduced systemic vascular resistance)
What would you hear on auscultation of ToF?
Loud, single S2: due to closure of aortic valve in diastole with absent/reduced pulmonary valve closure (P2) depending on the degree of stenosis.
Loud harsh ejection systolic: best auscultated either mid or upper left sternal edge (LSE). The smaller the VSD the louder the murmur and vice versa.
Ejection click: high pitch noise which occurs at the maximal opening of semilunar (aortic or pulmonary) valves. Clicks in TOF occur due to presence of dilated aorta. Normally heart immediately after S1.
Continuous, machinery murmur: occurs in the presence of PDA with extreme forms of TOF, especially those on prostaglandin infusion. Best auscultated at the upper LSE or left infraclavicular area.
What is the management of ToF?
Medical
Squatting
a) Increases venous return therefore increases systemic resistance
b) Put child in this position whilst waiting for medical review
Prostaglandin infusion
a) This maintains patent ductus arteriosus (in severe TOF)
Beta Blockers propranolol is commonly used in both ‘tet’ spells and prophylaxis in moderate severe disease
a) Peripheral vasoconstrictor and by relieving sub pulmonary muscular obstruction
Surgical
Surgery at 6 months to close VSD, relieve pulmonary tract obstruction
What are the complications of ToF?
Polycythaemia Cerebral abscess Stroke Infective endocarditis Congestive cardiac failure
What is the hallmark of transposition of the great arteries?
Ventriculoarterial discordance
What is the presentation of TGA?
Cyanosis
a) Appears in first 24 hours (if no mixing at the atrial level)
Mild cyanosis - particularly when crying
Signs of congestive heart failure: Tachypnea, Tachycardia, Diaphoresis, Failure to gain weight
From Examination: Prominent right ventricular heave Single second heart sound, loud A2 Systolic murmur potentially if VSD present No signs of respiratory distress
How would you investigate TGA?
Pulse oximetry
Capillary blood gas → metabolic acidosis with decreased PaO2. As there is a lack of oxygen going to distal organs, cells respire anaerobically producing lactate.
ECG= Normal
Imaging
Echocardiogram - essential to demonstrate the abnormal arterial connections
CXR
Egg on a string - due to potentially narrowed upper mediastinum: cardiomegaly and increased pulmonary vascular markings
How would you initially manage TGA?
Emergency prostaglandin E1 infusion to keep the ductus arteriosus patent as a temporary solution that allows mixing of blood
Prostaglandins are high during antenatal period - so used to maintain that same state.
Correct metabolic acidosis
Emergency atrial balloon septostomy to allow mixing.
How would you manage TGA long-term?
Surgical correction, commonly arterial switch operation (ASO) is usually performed before the age of 4 weeks.
Emergency balloon atrial septostomy may be required.
Long term follow up and counselling in the future if female patients want to get pregnant.
What is Eisenmenger syndrome?
Complication of long standing L→R Shunt causes Pulmonary hypertension and eventually switches into a R→L shunt.
What are the two types of ASD?
Secundum ASD (80%) a) defect in centre of atrial septum involving the foramen ovale
Partial atrioventricular septal defect
What are the clinical signs of ASD?
None
Recurrent chest infections / wheeze
Arrhythmias (fourth decade onward)
Physical signs:
Ejection systolic murmur best heard in the upper left sternal edge - due to increased flow across the pulmonary valve because of the left to right shunt.
A fixed and widely split second heart sound - due to right ventricular stroke volume being equal in both inspiration and expiration.
How would you investigate an ASD?
Chest X ray:
Cardiomegaly
Enlarged pulmonary arteries
Increased pulmonary vascular markings
ECG:
Right axis deviation due to right ventricular enlargement
ECHO:
Diagnostic
How would you manage an ASD?
Surgical Tx
Treatment aim is to prevent right side heart failure and arrhythmias in later life.
With a VSD what affects the intensity of the murmur?
Smaller the defect the louder murmur
Common (30% of all cases of CHD)
Classified due to size
What is the difference between a small and large VSD?
Small = Smaller than the aortic valve in diameter - up to 3mm
Large = The same size or bigger than the aortic valve
What are the signs of a small VSD?
Asymptomatic
Loud pansystolic murmur at lower left sternal edge
Loud murmur implies small defect
Quiet pulmonary second sound
What are the investigations for a small VSD?
X ray: Normal
ECG: Normal
ECHO:
Demonstrates precise anatomy of defect
Doppler echocardiography - assess haemodynamic effect
No pulmonary hypertension
How do you manage a small VSD?
It closes spontaneously
What is the presentation of a large VSD?
Heart failure
Breathlessness
Faltering growth after 1 week old
Physical Signs:
Tachypnoea, tachycardia, enlarged liver from HF
Active precordium
Pansystolic murmur or no murmur (implying large defect)
Loud pulmonary second sound from raised pulmonary arterial pressure
What are the investigations for a large VSD?
X ray: Cardiomegaly Enlarged pulmonary arteries Increased pulmonary vascular markings Pulmonary oedema
ECG:
Biventricular hypertrophy by 2 months of age
ECHO:
Demonstrates precise anatomy of defect
Doppler echocardiography - assess haemodynamic effect
Pulmonary hypertension (due to high flow)
What are the manage for a large VSD?
Diuretics (for HF) Captopril (ace inhibitor) Additional calorie input Surgery performed at 3-6 months Manage HF and faltering growth: a) Prevent permanent lung damage from pulmonary b) hypertension and high blood flow.
What is a PDA?
Persistent Ductus arteriosus
Ductus arteriosus connects the pulmonary artery to the descending aorta
In term infants - closes shortly after birth
PDA Failed to close 1 month after expected date for delivery due to failed constrictor mechanism
The flow of blood across a persistent ductus arteriosus is then form the aorta to the pulmonary artery (left to right)
How does a PDA present?
Continuous murmur beneath left clavicle
Collapsing or bounding pulse
If duct is large - pulmonary hypertension and heart failure.
How do you investigate and manage PDA?
Investigations:
Identified via ECHO
Management:
Closure is recommended to abolish risk of bacterial endocarditis
Closure - surgical coil
What is an atrioventricular defect, how does it present and how is it managed?
Commonly seen in children with downs syndrome
Complete Atrioventricular septal defect =
In middle of heart with a single five leaflet valve between the atrium and ventricles across the whole atrioventricular junction (tends to leak)
Clinical Features: Pulmonary hypertension Presentation on antenatal US screening Cyanosis at birth or HF at 2-3 weeks No murmur heard There is always a superior axis on the ECG
Management:
Treat HF medically (as for large VSD)
Surgical repair 3-6 months old.
What is aortic stenosis, how does it present and how is it managed?
Aortic valve leaflets are fused together - giving restrictive exit from the left ventricle
Associated with mitral valve stenosis and coarctation of the aorta
Clinical Features: Asymptomatic murmur
Signs:
Small volume slow rising pulse
Carotid thrill
Mx - balloon valvotomy if symptomatic on exercise or pressure > 64 mmHg
What is pulmonary stenosis and how would it present?
Valve leaflets fused together
Mostly asymptomatic
ECG
Right ventricular hypertrophy (upright T wave in T1)
Dilatation using balloon when pressure > 64 mmHg
What are the RFs for infective endocarditis?
It is most commonly seen in patients with a history of congenital or acquired cardiac disease. Ventricular septal defects Patent ductus arteriosus Aortic valve abnormalities Tetralogy of fallot IV drug users
What is the pathophysiology of IE?
Need a triad
a) Endothelial damage
b) Platelet adhesion
c) Microbial adherence
Structural abnormalities of the heart lead to a significant pressure gradient with or without turbulent flow leading to endothelial damage through sheer stress.
Bacteria are protected within the vegetation from phagocytic cells and host defence mechanisms and can proliferate easily.
What is the microbiology of IE?
Organisms that cause IE
Have specific surface receptors for fibronectin that allow the microbe to ashere to the thrombus at the outset
Staph. Aureus
Strep. Viridans (Commonly found after dental procedures)
What are the clinical features of IE?
Persistent low grade fever (without clear focus)
Heart murmur (due to turbulent flow)
Splenomegaly (70%)
Cutaneous manifestations are uncommon in paeds.
Petechiae
Osler nodes (Painful erythematous raised lesions on ends of fingers and toes)
Janeway lesions (Small painless, erythematous hemorrhagic raised lesions on palms or soles)
Splinter hemorrhages (Linear haemorrhagic streaks in the nail bed).
What are the investigations for IE?
Blood cultures ECHO: Identify vegetations and assess intracardiac damage FBC Anaemia Leukocytosis ESR = raised
What is the diagnestic criteria for IE?
Modified duke’s criteria
Infective endocarditis diagnosed if pathological criteria positive, or 2 major criteria, or 1 major and 3 minor criteria, or 5 minor criteria
What is pathological criteria for IE?
Positive histology or microbiology of pathological material obtained at autopsy or cardiac surgery (valve tissue, vegetations, embolic fragments or intracardiac abscess content)
What are the two major criteria for a diagnosis of IE?
Positive blood cultures
two positive blood cultures showing typical organisms consistent with infective endocarditis, such as Streptococcus viridans and the HACEK group, or
persistent bacteraemia from two blood cultures taken > 12 hours apart or three or more positive blood cultures where the pathogen is less specific such as Staph aureus and Staph epidermidis, or
positive serology for Coxiella burnetii, Bartonella species or Chlamydia psittaci, or
positive molecular assays for specific gene targets
Evidence of endocardial involvement positive echocardiogram (oscillating structures, abscess formation, new valvular regurgitation or dehiscence of prosthetic valves), or new valvular regurgitation
What are the minor criteria for IE?
predisposing heart condition or intravenous drug use
microbiological evidence does not meet major criteria
fever > 38ºC
vascular phenomena: major emboli, splenomegaly, clubbing, splinter haemorrhages, Janeway lesions, petechiae or purpura
immunological phenomena: glomerulonephritis, Osler’s nodes, Roth spots
How do you manage IE?
For highly sensitive streptococci IV penicillin or IV ceftriaxone for 4 weeks
What is acute rheumatic fever?
Systemic illness that occurs 2-4 weeks after pharyngitis
Due to cross reactivity to group A beta=haemolytic strep (GAS)
Strep Pyogenes
What is the epidemiology and RFs for acute rheumatic fever?
Most common in tropical countries with no seasonal variation
Children and young people
Poverty
Overcrowded and poor hygiene places
FH
What is the name of the criteria for diagnosing acute rheumatic fever?
Revised Jones Criteria
Recent sore throat or scarlet fever
2 major criteria OR 1 major and 2 minor criteria present for initial ARF. (Same criteria for recurrent ARF plus can also be just 3 minor criteria)
What are the major criteria in the Revised Jones Criteria ?
SPECS
Sydenham’s chorea (Involuntary movements)
Polyarthritis (Doesn’t last long in one particular joint)
Erythema marginatum (Rash on trunk and limbs - pink macules spread outwards).
Carditis (Endocarditis (sig. murmur)
Subcutaneous nodules
What are the minor criteria in the Revised Jones Criteria ?
CAPE
CRP or ESR – Raised acute phase reactant
Arthralgia
Pyrexia/Fever
ECG – Prolonged PR interval
*Joint (arthritis or arthralgia) and cardiac (carditis or prolonged PR interval) manifestations can only be counted once, not twice, as either a major or a minor criterion.
*Slight variation of criteria for high risk population
How do you investigate acute rheumatic fever?
Bloods: ESR, CRP, FBC (WBC) Blood cultures - to exclude sepsis Rapid antigen detection test Throat culture: may be negative by the time rheumatic fever symptoms occur. Anti-streptococcal serology ECG: prolonged PR interval CXR: if carditis is suspected congestive heart failure ECHO
How do you manage rheumatic fever?
1st line abx: benzathine benzylpenicillin
2nd line abx: phenoxymethylpenicillin/ erythromycin
For arthritis give aspirin, naproxen or ibuprofen
Diuretics are usually used first and are effective in mild to moderate heart failure. Furosemide and spironolactone are the most commonly used diuretics.
For disabling chorea give carbamazepine
What is the long-term management of rheumatic fever?
Secondary prophylaxis with IM benzathine benzylpenicillin every 3-4 weeks, oral phenoxymethylpenicillin twice daily, oral sulfadiazine daily and or oral azithromycin :
What is the prognosis of rheumatic fever?
2% can get permanent damage to heart valves and chronic rheumatic heart disease
What can occur in children when given aspirin?
Reye’s syndrome
An acute encephalopathy with hepatic dysfunction stemming from mitochondrial damage. Treatment includes intensive supportive care, correction of metabolic abnormalities, and control of intracranial pressure.
What is Kawasaki disease?
Systemic Vasculitis
6 months - 4 years
Aetiology = unknown
What are the clinical features of Kawasaki disease?
CRASH & BURN
Bilateral nonexudative conjunctivitis
Polymorphous rash - esp on trunk (Red blanching rash)
Cervical Lymphadenopathy (Often unilateral, firm tender nodes. Bigger - 1.5 cm)
Pharyngeal injection, dry fissured lips, strawberry tongue. No tongue ulcers
Changes in extremities (Arthralgia, palmar erythema, swelling of the hands and feet)
Plus fever for 5 days or more
How do you investigate Kawasaki disease?
Bloods: FBC, ESR, CRP
Echo
What are the RFs for Kawasaki disease?
Asian
3 months - 4 years
Male
How do you manage Kawasaki disease?
1st line: intravenous immunoglobulin
With aspirin for anti-platelet effect
2nd line: methylprednisolone if 2 lots of IVIG don’t reduce symptoms
3rd line: Infliximab. A chimeric monoclonal antibody to tumour necrosis factor (TNF)-alpha.
Why and what do you need to follow up after Kawasaki disease?
ECHO - to follow up
Coronary arteries are affected in ⅓ of cases within 6 weeks of infection. Scarring can cause myocardial ischemia and aneurysm
