Cardiology Flashcards
What is the definition of an acceleration of CTG?
An abrupt increase in the baseline foetal HR of > 15 bpm for > 15 seconds
Reassuring. Occur alongside uterine contractions
Their absense is not necessarily bad
What murmur is heard in an ASD?
Systolic ejection murmur over the left second ICS sternal border
Widely split second heart sound which is fixed
What congenital heart defect will cause a boot-shaped heart on CXR?
Tetralogy of Fallot
Right ventricular hypertrophy
What is Eisenmenger syndrome?
A left-to-right shunt becomes a cyanotic right-to-left shunt
Left-to-right shunt → increased pulmonary flow → pulmonary hypertension → right ventricle hypertrophy → right ventricular pressure exceeds left ventricle pressure → the shunt reverses → right to left shunt → cyanosis
What is the tetralogy of Fallot?
- Pulmonary valve stenosis
- Right ventricular hypertrophy
- Ventricular septal defect
- Overriding aorta (above VSD)
How are murmurs graded?
What is a normal foetal baseline rate?
>32 weeks 110-160 bpm
<32 weeks 125-160 bpm
What is the definition of a deceleration on CTG?
An abrupt decrease in baseline HR of > 15 bpm for > 15 seconds
What is the cause of this CTG abnormality?
Early decelerations
Uterine contraction → increased ICP → increased vagal tone
What is more common, an ostium primum or secundum ASD?
Secundum (70%)
Which pneumonic is used for cardiotocohraphy (CTG) interpretation?
DR C BRAVADO
DR - define risk
C - contractions
BRa - baseline rate
V - variability
A - accelerations
D - decelerations
O - overall impression
What causes closure of the foramen ovale?
Expansion of the lungs at birth → increased pulmonary blood flow → increased pressure in the RA → apposition of the septum primum and secundum
What is the most common congenital heart defect?
VSD
Name 4 non-cyanotic congenital heart diseases
- ASD
- VSD
- PFO
- PDA
- Coarctation of the aorta
- Endocardial cushion defect
What are 2 risk factors for a patent ductus arteriosus?
- Prematurity (ductus arteriosus in a preterm is less responsive to O2 and is less likely to constrict after birth)
- Maternal rubella infection
- Maternal prostaglandin administration
- Trisomies
What murmur is heard in a VSD?
Holosystolic mumur over the left sternal border
Mid-diastolic murmur over the cardiac apex (increased flow through the mitral valve)
What causes of closure of the ductus arteriosis?
O2 levels rise → vasoconstriction
Lungs release bradykinin → vasoconstriction
Prostaglandin E2 levels drop → vasoconstriction
What features suggest a benign paediatric murmur?
Grade 2 or less intensity
Short systolic duration (not holosystolic or diastolic)
Minimal radiation
Musical or vibratory (not harsh or blowing)
Softer intensity when sitting upright
Normal S2
Go gallop, click or rub
What is the definition of prolonged severe bradycardia?
Less than 80 bpm for more than 3 minutes
Children with Tetralogy of Fallot will often do what to decrease R-L shunting?
Squat
Increases systemic vascular resistance → increases LV pressure
Which congenital heart diseases are associated with Turner syndrome?
Coarctation of the aorta
Bicuspid aortic valve
Which cardiac murmurs are associated with Marfan syndrome?
Mitral valve prolapse
Aortic root dilation
Aortic regurgitation
Pre-syncope or syncope is associated with which congenital heart diseases?
Aortic stenosis
Hypertrophic cardiomyopathy
Weak or absent femoral pulses is associated with which congenital heart disease?
Coarctation of the aorta
What is the best sign of heart failure in children?
Hepatomegaly
When does the foramen ovale close?
At birth
When does the ductus arteriosus close?
2-3 days following birth
What are some of the adverse effects associated with symptomatic PDAs in preterm infants?
Pulmonary hyperperfusion
- Pulmonary haemorrhage
- Bronchopulmonary dysplasia
Cerebral, mesenteric and renal hypoperfusion
- Metabolic acidosis
- Intracranial haemorrhage
- Periventricular leukomalacia
- Necrotising enterocolitis
- Oliguria
Which cardiac disorder is associated with fixed splitting of the S2 heart sound?
Atrial septal defect
There is a left to right shunt through the ASD which results in increased RA and RV volumes. As a result, there is increased flow through the pulmonic valve such that, regardless of breath, the pulmonic valve closes later every time.
What is the structual difference between an ASD and a PFO?
The septal defect in ASD is due to missing tissue
PFO results from an unfused septa
An egg-shaped heart on CXR is characteristic of which condition?
Transposition of the great vessels
What congenital heart disease may have this CXR?
Total anomalous pulmonary venous return
A machinery murmur is characteristic of which congenital heart disease?
PDA
What might the findings on clinical examination of a child with a PDA be?
Heavy “machinery” continuous murmur
Tachycardia
Wide pulse pressure, bounding pulse
Hyperactive precordium
How can cardiac and other causes of cyanosis be differentiated?
Hyperoxic test
Obtain preductal right radial ABG in RA → repeat after child inspires 100% oxygen
If PaO2 improves significantly, cyanosis is unlikely cardiac
What is auscultated in tetralogy of fallot?
Harsh systolic murmur
Due to right ventricular outflow obstruction (pulmonary stenosis)
What is auscultated in transposition of the great vessels?
Single S2
Holosystolic murmur if VSD is also present
A systolic ejection murmur and fixed splitting of S2 is characteristic of which cardiac condition?
ASD
What heart condition is fragile X associated with?
Mitral valve prolapse
What is Ebstein’s abnormality?
Malformed and displaced tricuspid valve leaflets causing tricuspid valve regurgitation and right heart enlargement
A continuous blowing noise heard below the clavicles is characteristic of which murmur?
Venous hum
What are the clinical features of Still’s murmur?
Vibratory or muscial quality along the left lower sternal border
Louder when supine or during hyperdynamic states
Benign
What is the most significant risk factor for Ebstein’s abnormality?
Prenatal lithium exposure
What is the most common cause of cyanosis in the first few weeks of life?
Tetralogy of Fallot
How might a left ventricular free wall rupture present following an MI?
Chest pain, dyspnoea
Cardiac tamponade (hypotension, distended neck veins, muffled heart sounds)
