A 40 year old woman recently diagnosed with celiac disease presents with fatigue. She says that she can only walk a few blocks or flights of stairs before she gets tired. She can't recall a specific incident that brought this on; now that she thinks about it, it's been going on for a while. Past medical history is remarkable only for the celiac disease. There is no pertinent family history. She has had three kids. On exam, everything seems within normal limits except for the finding shown below.
Challenge: What's the diagnosis?
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