congenital defects

Question 1

A 45 year old mother missed most of her antenatal scans and check ups. She gave birth to her son yesterday in an uncomplicated delivery. However, during feeding she has noted that her son often tires easily and becomes disinterested in feeding any longer. Then this morning she became very worried as he appeared to turn very blue especially in the face. Given the probable cause of these symptoms what would be the best investigation to confirm the diagnosis?

Answer 1

echo

Question 2

tetraology of fallot what does this include

Answer 2

Ventricular septal defect (VSD)
Overriding aorta - i.e., an aorta that overrides the right and left ventricles as a result of the VSD
Right ventricular outflow tract obstruction (RVOTO) - this is the main determinant of the severity of cyanosis
Right ventricular hypertrophy

Question 3

shape of heart in tet

Answer 3

boot shaped

Tetralogy of Fallot is most commonly diagnosed antenatally, or on detection of a murmur in the first few months of life.
May also present with cyanosis
Babies can present with tet spells, which are acute episodes of cyanosis. During a tet spell, there is reversal of the shunt across the VSD, resulting in a right-to-left shunt and worsening cyanosis.

Question 4

This is an emergency and can be fatal
Acutely: lie babies on their back and bend their knees. In hospital, oxygen should also be provided.
Prophylaxis: propranolol may be used by some centres

is the management of tet
Which of the following is reserved for the treatment of severe episodes of this patient’s presentation?

Answer 4

phenylephrine - severe tet spells managed with vaso-constrictive agent as last line medical therapy . vaso-c helps increase systemic vascular resistance , reducing the right to left shunt and therefore improving cyanosis

Question 5

Which finding from the echocardiogram is most important in determining the severity of his cyanosis?

Answer 5

degree of RVOTO / pulmonary stenosis

Atria normal size. Atrial septum intact. Ventricles normal size. Large ventricular septal defect noted with over-riding aorta. Aortic arch normal. Accompanying ECG normal. Stenosis to right ventricular outflow tract above the pulmonary valve. The ductus arteriosus is patent.