Cardio Flashcards
How does the antenatal heart and lungs work?
the lungs are filled with fluid and there is a very high pulmonary vascular resistance
lungs are non-functional
Blood comes from umbilical vein into fetal IVC -> Right atrium
not much blood can reach lungs through pulmonary artery
there are therefore shunts to help mixing of blood
- Ductus arteriosus - between aorta and pulmonary artery
- Foramen ovale - between left and right atrium
what are cyanotic heart diseases ? list some - how do we tell the difference
cause the baby to become cyanosed
- Tetralogy of fallot
- presents within months
- more likely to have murmur!
- Xray; boot shaped heart
- Transposition of the great arteries
- presents within days
- no response of Pa02 to oxygenation (hyperoxia test/ (nitrogen washout test)
- Xray; egg on a string
how do we ivx cyanotic heart diseases?
Antenatally:
- may be identified on anomaly scan 20 wks
Post natally:
- Physical exam; murmur, cyanosis, signs of heart failure
- Xray
- Echocardiogram
- Hyperoxia test; give high flow O2, will note some response in TOF
How do we mx cyanotic heart diseases?
- Maintain Patent ductus arteriosus until corrective surgery:
- Give IV prostaglandin infusion
- Surgery
What are the acyanotic heart diseases?
how do they present?
Atrial septic defect:
- asymptomatic
- may hear ESM - Ejection systolic murmur @ left sternal edge
Fixed splitting S2
Ventricular septal defect:
- asymptomatic
- pansystolic murmur at LSE aka holosystolic
- rx: spontaneous resolution / surgery
Atrioventricular septal defect
- down syndrome
- pulmonary vascular congestion
- pulmonary htn
Patent ductus arteriosus
- normally closes within 1 month of birth but in PDA it doesnt
- continuous murmur under left clavicle
- give NSAIDs; inhibits prostaglandin
what are the consequences of congenital heart disease?
-
what factors increase the risk of congenital HD?
Maternal → Rubella infection; DM; Warfarin; FAS - fetal alcohol syndrome
Chromosomal → Down’s; DiGeorge; Edward’s; Patau’s; Turner; William’s; Noonan’s
what are the most common congenital heart lesions that cause the following presentations:
- breathless child
- blue/cyanotic child
- breathless and blue
• Left-to-right shunts (breathless child)
○ Ventricular septal defect 30%
○ Persistent arterial duct 12%
○ Atrial septal defect 7%
• Right-to-left shunts (blue/cyanotic child)
○ Tetralogy of Fallot
○ Transposition of the great arteries
• Common mixing (breathless and blue)
○ Atrioventricular septal defect (complete)
what are the most common congenital heart lesions that cause the following presentations:
- asymptomatic with a murmur
- collapsed with shock
1• Outflow obstruction in a well child (asymptomatic with a murmur)
○ Pulmonary stenosis
○ Aortic stenosis
2• Outflow obstruction in a sick neonate (collapsed with shock)
○ Coarctation of the aorta
what is the MOST COMMON presentation of congenital heart disease?
heart murmur
what are the causes of murmur in neonates?
Vast Majority:
- Normal benign/innocent aka flow murmurs
- The s's of innocence → Soft - eg does not radiate anywhere Systolic, Asymptomatic, left Sternal edge - doesnt rule out unless all other features are benign Sensitive - to changes in position
so a diastolic murmur is always pathological
which CHD present:
A. within first few hours?
B. within first few days?
A• First few hours → pulmonary or aortic atresia, critical stenosis, hyperplastic heart syndrome
B• First few days → TGA, ToF, large PD Arteriosus In premature contraction
which CHD present:
- First few weeks
- First few months
A• First few weeks → AS, coarctation
B• First few months → any L to R shunt as pulmonary resistance falls
• Majority of murmurs in paeds are innocent
What is EISENMENGER syndrome?
what is. the aetiology?
Eisenmenger’s syndrome is defined as the process in which a long-standing left-to-right cardiac shunt caused by a congenital heart defect (typically by a ventricular septal defect, atrial septal defect, or less commonly, patent ductus arteriosus)
causes pulmonary hypertension, pulmonary congestion, increased resistance in pulmonary artery (thickened walls) and increased Right heart pressure
this leads to eventual reversal of the shunt into a right-to-left shunt (as rt pressure exceeds the left) - around 10-15years of age
this leads to systemic stigmata including:
cyanosis, clubbing, polycythaemia
this happens because the right to left shunt leads to more de-oxygenated blood being pumped around the body = reduced cell function and blue tinge/cyanosis of skin.
what is the treatment of EISENMENGER syndrome?
Ideally treat heart defect before R-L shunt develops
After pulmonary hypertension is sufficient to reverse the blood flow through the defect, however, the maladaptation is considered irreversible, and a heart–lung transplant or a lung transplant with repair of the heart is the only curative option.
Transplantation is the final therapeutic option and only for patients with poor prognosis and quality of life.
what are the possible signs and sx of EISENMENGER syndrome?
Note: when it is a LR shunt, it is not cyanotic disease until reversal.
Cyanosis (a blue tinge to the skin resulting from lack of oxygen)
High red blood cell count - polycythaemia
Clubbing
Fainting (also known as syncope)
Heart failure
Abnormal heart rhythms
Bleeding disorders Coughing up blood Iron deficiency Infections (endocarditis and pneumonia) Kidney problems Stroke - if a peripheral embolus comes into rt side -> left -> brain, instead of becoming a pulmonary embolus
Gout (rarely) due to increased uric acid resorption and production with impaired excretion
Gallstones
what is the prognosis of EISENMENGER syndrome?
With increased fetal screening, Left-right shunts can be fixed early meaning that patients wont later develop eisenmengers
If they do develop it, they. usually die in their 40s/50s with heart failure.
variable post transplant
what are the Left to right shunts?
These are:
• atrial septal defects (ASDs)
• VSDs
• persistent ductus arteriosus (PDA).
what are the types of ATRIAL SEPTAL DEFECT (ASD)?
There are two main types of ASD:
• Ostium Secundum ASD (80%)
• Partial atrioventricular septal defect (AVSD or ostium primum - 20%)
The secundum ASD:
- defect in the centre of the atrial septum involving
the foramen ovale.
Partial AVSD:
- defect of the Atrioventricular septum (between the right atrium and the left ventricle) ->
- inter-atrial communication between the bottom
end of the atrial septum and the atrioventricular
valves (primum ASD) - Left AV valve has 3 leaflets & leaks (regurgitant valve).
how does ATRIAL SEPTAL DEFECT (ASD) present?
Both types present with similar symptoms and signs
- None /asymptomatic (commonly)
- Recurrent chest infections/wheeze
- Arrhythmias (fourth decade onwards)
• Ejection Systolic murmur (due to ↑ pulmonary valve flow)
+ fixed widely split 2nd HS (you hear Lub-du-dub, instead of Lub-dub)
• AVSD gives an apical pansystolic murmur
from atrioventricular valve regurgitation.
what is the aetiology of fixed widely split 2nd HS in ASD?
pulmonary valve closes slightly later than aortic valve so you hear Lub-du-dub, instead of Lub-dub
due to the right ventricular stroke volume being equal in both inspiration and expiration.
How do we ivx ATRIAL SEPTAL DEFECT (ASD) ?
IX: CXR, ECG, Echo
- CXR → cardiomegaly, large pulmonary arteries, ↑ pulmonary markings
- ECG → partial RBBB or RAD due to RV enlargement
superior QRS axis position in AVSD
• Echo → see anatomy
How do we manage ATRIAL SEPTAL DEFECT (ASD) ?
why do we treat?
→ if significant* cardiac catheterisation (cath lab) with insertion of occlusion device (3yo-5yo)
*(large enough to cause right ventricle dilation)
AVSD: Surgery / surgical correction needed
- if complete, repair at 3-6 months
reasons to treat:
to prevent right heart failure and arrhythmias in later life.
and of course Phtn,eisenmenger etc
what are the complications of L-R shunts eg ASD, VSD, PDA?
causes pulmonary hypertension, pulmonary congestion, increased resistance in pulmonary artery (thickened walls) and increased Right heart pressure
Then subsequent:
Eisenmenger
Heart failure
Arrhythmias etc
Risk of Bacterial endocarditis - prevent by good dental hygiene
what are the types of VSD?
There is a defect anywhere
in the ventricular septum
- Peri-Membranous - (adjacent to the tricuspid valve)
- Muscular - (completely surrounded by muscle).
They can most conveniently be considered according to the size of the lesion:
Small (<3mm, diameter smaller than aortic valve)
Large (>aortic valve)
How do small and large VSDs present?
Small (<3mm, diameter smaller than aortic valve)
o Asymptomatic, loud PSM (pansystolic) at LLSE
o Quiet pulmonary 2nd sound
o CXR and ECG normal
Large (>aortic valve)
o Sx: HF + SOB and failure to thrive after 1wo
o Sx: Recurrent chest infections
o Signs: ↑ HR ↑ RR, Heptatomegaly;
2 murmurs: Soft PSM (pansystolic) - quiter than in small vsd, Apical mid-diastolic murmur
o Loud pulmonary HS 2 (due to increased pulmonary pressure)
How do we IVX VSDs?
Remember small VSD- cxr, ecg = normal
• CXR → cardiomegaly, enlarged pulmonary arteries, increased pulmonary vascular markings + pulmonary
oedema
- ECG → biventricular hypertrophy by 2months
- Echo → anatomy, haemodynamic effects, pulmonary HTN
how do we mx VSDs?
Large VSDs
Treat HF with diuretics + captopril (ACE-I).
(note this is not done in ASD)
Surgery at 3-6m to prevent permanent lung damage.*
- note there will deffo be a degree of Phtn in these kids - surgery is to prevent Eisenmenger + permanent issues.
Again - small VSDs can spontaneously patch up
Risk of Bacterial endocarditis - prevent by good dental hygiene
increased calories
How does PDA present?
Continuous murmur under L. clavicle
• Increased pulse pressure, collapsing or
bounding pulse
• If large will show signs of growth failure and
pulmonary HTN
How do we IVX and MX PDA?
• CXR and ECG → normal if small, if large,
findings same as VSD (cardiomegaly and
enlarged pulmonary arteries)
• Echo → to distinguish PDA and VSD
MX:
Use of coil or occlusion device via cardiac catheter at 1
year old.
Risk of Bacterial endocarditis - prevent by good dental hygiene
what are the components of TETRALOGY OF FALLOT (TOF)?
[1] large VSD
[2] overriding aorta - sits midway, so receives blood from both left and right ventricles.
[3] sub-pulmonary stenosis (RV outflow obstruction) and resulting
- RV hypertrophy
how does TETRALOGY OF FALLOT (TOF) present?
R-L shunt
MOST common cause of cyanotic congenital
heart disease
• Classic presentation → cyanosis, hypercyanotic
spells, squatting during exercise
(Exercise = more deoxygenated blood = more cyanosis as poor oxygenation due to numerous shunts. Squats increase systemic resistance-> more blood shunted from aorta to pulmonary artery/lung = blood is oxygenated )
Presents 1st week of life
• ‘Tet spells’ → quick increase in cyanosis,
associated with irritability or inconsolable crying,
SOB, pallor. THIS is an EMERGENCY
- occur becuase there is sudden increase in deoxygenated blood shunted into aorta (levels of mixing always change)
• Signs → clubbing, loud harsh ejection systolic
murmur at LSE from day 1 of life
how do we ivx TETRALOGY OF FALLOT (TOF)?
CXR → small, boot-shaped heart with uptilted
apex. Pulmonary artery ‘bay’, concave cavity on
left border
• ECG → may develop RV hypertrophy when
older
• Echo → shows cardinal features but cardiac
catherization may be required to show detailed
anatomy of the coronary arteries.
How is TETRALOGY OF FALLOT (TOF) managed?
1• Hypercyanotic spells usually self-limiting:
• If prolonged, 15mins+, give sedation and pain
relief – morphine, IV propranolol (vasoconstrict),
IV fluids, bicarbonate (to correct acidosis)
- Surgery at 6m (close VSD and relieve
R outflow obstruction) - definitive - If very cyanosed neonate,
- insert BT shunt !!
to increase pulmonary blood flow between subclavian and pulmonary (Blalock-Taussig) - this sends the mixed blue/red blood back to lung to be better oxygenated.
what are the Right-to-left shunts and how do they present?
These are:
• tetralogy of Fallot
• transposition of the great arteries.
Presentation is with cyanosis (blue, oxygen satura-
tions ≤94%, or collapsed), usually in the first week of life.
