Structural Heart Defects

Question 1

Atrial Septal Defect (type of shunt, Sx, complications Ix, Tx)

Answer 1

Often diagnosed in adulthood

Left –> Right shunt as pressure in LA>RA

Sx: dyspnoea, exercise intolerance, AFib, wide and split S2 (delayed closure of pulmonary valve as more blood from RA is squeezing through it), pulmonary ejection systolic murmur

Complications: pulmonary HTN can cause Eisenmenger’s syndrome, where shunt is reversed to R–>L and becomes cyanotic. This is because RV becomes hypertrophic to accomodate increased flow of bood into RA.

Ix: ECG showing RBBB due to V dilatation, echo

Tx: surgical closure in symptomatic adults

Question 2

Ventricular Septal Defect (type of shunt, Sx, complications Ix, Tx)

Answer 2

Defect in ventricular septum, may close spontaneously during childhood. Initially acyanotic. Risk more likely if mum has DM during pregnancy, in all the trisomies.

Sx: LOUD systolic murmur, thrill, normal HR and heart size in small defects. In large defects, increased RR, small, breathless, skinny baby, BIG heart, eventual Eisenmenger’s

Complications: pulmonary HTN can cause Eisenmenger’s syndrome, where shunt is reversed to R–>L and becomes cyanotic. This is because RV becomes hypertrophic to accomodate increased flow of bood into RA.

Ix: Echo

Tx: if small defect, no intervention and/or prophylactic abx. If large defects, furosemide, ramipril, digoxin, surgical closure.

Question 3

Atrioventricular Septal Defect (type of shunt, Sx, Tx)

Answer 3

Hole in the centre of the heart that involves ventricular and atrial septums, and mitral and tricuspid valve. Associated withh Down’s syndrome.

Sx: If complete defect, breathless as neonate, poor weifht gain and feeding. if partil defect, will present a bit later with dyspnoea, tachycardia, exercise intolerance.

Tx: pulomary artery banding to decrease risk of pulmonary HTN

Question 4

Patent Ductus Arteriosus (type of shunt, Sx, complications Ix, Tx)

Answer 4

Persistent communication between pulmonary artery and descending aorta. Blood shunts from aorta to pulmonary artery, lung circulation is overloaded –> Eisenmenger syndrome and RHF. Increased risk of IE.

Sx: continuous machinery murmur, palpitations, cyanosis (clubbed and blue toes)

Ix: CXR, ECG, Echo

Tx: Indomethacin (prostaglandin inhibitor) can stimulate duct closure, surgery

Question 5

Coarctation of the Aorta
(type of shunt, Sx, complications Ix, Tx)

Answer 5

Narrowing of aorta at/distal to insertion of ductus arteriosis –> excessive blood flow beig diverted through carotid/subclavian vessels –> stronger perfusion to upper body compared to lower. Decreased renal perfusion –> systemic HTN. Increased afterload = LVH.

Associated with Turner syndrome.

Sx: Often asymptomatic for many years, headaches and nosebleeds (due to HTN), claudication and cold legs, HTN in upper limbs, low BP in lower legs, weak femoral pulse, radial-femoral delay, bruits over scapular and back from collateral vessels

Ix: CXR, ECG, CT/MRI aortogram is diagnostic

Tx: balloon angioplasty and stenting, BBlockers

Question 6

Tetralogy of Fallot
(type of shunt, Sx, complications Ix, Tx)

Answer 6

Most common form of cyanotic congenital heart disease.

1. Large VSD
2. Overriding aorta
   3.Pulmonary stenosis (RV outflow obstruction)
3. RVH

Associated with trisomy 21, FAS.

Sx: central syanosis, low birthweight and growth, dyspnoea

Ix: ECG (RVH), CXR (boot-shaped heart), echo

Tx: surgical closure of VSD, longterm BBlockers