A 6week old with irritability and poor feeding

A 6 week old is brought to your rural emergency department with several days history of irritability and poor feeding.
On history there was poor/no antenatal care and the child was a home birth. On examination the child is afebrile, with a tachycardia and is haemodynamically stable. There is a 4/6 holosystolic  murmur on cardiac auscultation and bilateral lung crepitations.
An ecg is done and is shown below.  Please answer the following:

1. What does the ECG show?
2. What is the most likely diagnosis?
3. What investigations would you perform?

WHAT Does the ECG show?

The rate is 138.
Normal P waves
The QRS's in V4-5 overlap, indicating a Left Ventricular Hypertrophy.
​This is most likely due to a Vetriculoseptal defect (VSD) 

WHAT is the most likely diagnosis

This is a VSD. VSD's cause a left to right shunt. Over time they result in pulmonary hypertension and right ventricular hypertrophy, which then reverses the shunt. This can lead to Eisenmenger's syndrome, resulting in cyanosis and heart failure.
At 4 to 6 weeks, the features of heart failure begin to appear.

what investigations would you like to order?

The diagnosis has almost been made clinically. We already have an ECG. We need a Chest-Xray, which may show cardiomegaly and a cardiac echo to follow.

Members please go to the paediatric ECG and Cardiac Conditions section