Older Than Stated Age

Source:  Older Than Stated Age    Tag:  cardiomegaly on cxr
A 12 year old boy is referred to your pediatric clinic for exercise intolerance. He had an unremarkable birth history, but as a young child, started developing abdominal pain, nausea, vomiting, and poor appetite. He was diagnosed with reflux, gastroenteritis, and failure to thrive, though none of the treatments he got worked. He later developed recurrent cough, shortness of breath, and wheezing but inhalers have not helped. After being frustrated with not getting answers, his parents brought him to you.

On exam, he has a heart rate 110 and regular. There is no murmur, but you note a heave. His extremities are cool and mottled, with decreased capillary refill and peripheral pulses. His blood pressures are low but similar on all extremities. He is slightly tachypneic and his pulmonary exam shows wheezing and rales. You palpate hepatomegaly and peripheral edema.

Here are your initial studies:

Challenge: What's your diagnosis?

Images shown under Fair Use.